;;; latex-math-preview.el --- preview LaTeX mathematical expressions.

;; Copyright 2006, 2007, 2008, 2009 Kevin Ryde
;; Copyright 2009-2019 Takayuki YAMAGUCHI

;; latex-math-preview.el is a modified version which is based on
;; tex-math-preview.el and has been created at July 2009.
;; This emacs lisp is made by reducing some features of tex-math-preview.el
;; and adjusting it to LaTeX files.
;; tex-math-preview.el is made by Kevin Ryde and 
;; has some features which latex-math-preview does not have.
;; Please see http://user42.tuxfamily.org/tex-math-preview/index.html
;; for details of tex-math-preview.el.

;; Author: Takayuki YAMAGUCHI <d@ytak.info>
;; Keywords: LaTeX TeX
;; Package-Version: 20190123.802
;; Version: 0.7.3
;; Created: Wed Jan 23 17:02:18 2019
;; URL: https://gitlab.com/latex-math-preview/latex-math-preview

;; This program is free software; you can redistribute it and/or modify it under
;; the terms of the GNU General Public License as published by the Free Software
;; Foundation; either version 3 of the License, or (at your option) any later 
;; version. 
;;
;; This program is distributed in the hope that it will be useful, but WITHOUT 
;; ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
;; FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. 
;; 
;; You should have received a copy of the GNU General Public License along with
;; this program. If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:
;; latex-math-preview creates images of particular region in LaTeX file
;; and display them in emacs.
;; latex-math-preview has the following main commands.
;; 
;; M-x `latex-math-preview-expression' previews a mathematical expression pointed
;; by the cursor in LaTeX files or strings of selected region with transient-mark on.
;; The result of this command is shown as an image in a popped-up buffer.
;; 
;; M-x `latex-math-preview-insert-symbol' displays the list of LaTeX symbols.
;; Selecting a LaTeX symbol in the list, you can insert it to a LaTeX file.
;; Depending on whether the cursor is in a mathematical expression or not,
;; this command shows an appropriate symbol list.
;; If you don't want to use the automatic mode selection of symbol list,
;; alternatively you may use M-x `latex-math-preview-insert-mathematical-symbol'
;; for mathematical symbols and M-x `latex-math-preview-insert-text-symbol'
;; and normal text symbols.
;;
;; M-x `latex-math-preview-save-image-file' makes an image for the same target
;; as `latex-math-preview-expression' and save it as a file which is png or eps.
;; When making an image, this command may remove automatically
;; numberings of mathematical formulas.
;; 
;; latex-math-preview.el automatically search \usepackage in the current buffer
;; and set the values to the buffer local variable `latex-math-preview-usepackage-cache'.
;; This values of \usepackage is used to create preview images.
;; When you add new \usepackage lines, to reload the variable `latex-math-preview-usepackage-cache'.
;; you can use M-x `latex-math-preview-reload-usepackage'.
;; If LaTeX source is splitted to multiple files and the current buffer does not include \usepackage lines,
;; you execute C-u M-x `latex-math-preview-reload-usepackage' and select the file including \usepackage lines.
;; 
;; There are \usepackage lines that are not appropriate to create preview images.
;; You can also filter such \usepackage lines. The variable `latex-math-preview-usepackage-filter-alist'
;; is the list of ignored \usepackage lines.
;; The values of the list `latex-math-preview-usepackage-filter-alist' are
;; (REGEXP) or (REGEXP . (lambda (line) SOME PROCESSES)).
;; For the former, matched \usepackage lines are ignored.
;; For the latter, if the evaluation of the lambda expression is nil
;; then matched \usepackage lines are ignored
;; and if the evaluation returns string then the string is added to
;; the variable `latex-math-preview-usepackage-cache'.
;; 
;; If the automatic search of \usepackage lines does not work,
;; you can edit directly the variable `latex-math-preview-usepackage-cache'.
;; To do so, you execute M-x `latex-math-preview-edit-usepackage'.
;; 
;; M-x `latex-math-preview-beamer-frame' makes an image of one frame of beamer,
;; which is a LaTeX style for presentation.
;; 
;; * Requirements
;; Because latex-math-preview displays png images in emacs,
;; it is not work in emacs on terminal, i.e., latex-math-preview needs emacs on X Window System.
;; 
;; ** Version of Emacs
;; latex-math-preview works probably on emacs with the version larger than 22.
;; The author tested latex-math-preview on Emacs 24.2.1 and Ubuntu 13.04.
;; Previously, the author confirmed latex-math-preview had no problem on Meadow 3 and Windows XP.
;; 
;; ** Image Conversion
;; latex-math-preview uses some commands to convert tex to png, tex to eps, and so on.
;; Only for previewing mathematical expressions, latex-math-preview requires
;; latex and dvipng commands.
;; According to your environment and your settings of latex-math-preview,
;; latex-math-preview creates preview images by combining the following commands.
;; 
;;  - dvipng
;;  - dvips
;;  - latex
;;  - platex
;;  - pdflatex
;;  - lualatex
;;  - dvipdf
;;  - dvipdfm
;;  - dvipdfmx
;;  - gs
;; 
;; * Install of Emacs Lisp
;; ** Load latex-math-preview
;; Put latex-math-preview.el to your load-path of Emacs and
;; write the following code in ~/.emacs.el.
;; 
;;   (autoload 'latex-math-preview-expression "latex-math-preview" nil t)
;;   (autoload 'latex-math-preview-insert-symbol "latex-math-preview" nil t)
;;   (autoload 'latex-math-preview-save-image-file "latex-math-preview" nil t)
;;   (autoload 'latex-math-preview-beamer-frame "latex-math-preview" nil t)
;; 
;; ** Key Bindings
;; Please set key bindings of your TeX mode if desired.
;; 
;; For example, for YaTeX mode we add the following settings to ~/.emacs.el.
;;
;;   (add-hook 'yatex-mode-hook
;;            '(lambda ()
;;            (YaTeX-define-key "p" 'latex-math-preview-expression)
;;            (YaTeX-define-key "\C-p" 'latex-math-preview-save-image-file)
;;            (YaTeX-define-key "j" 'latex-math-preview-insert-symbol)
;;            (YaTeX-define-key "\C-j" 'latex-math-preview-last-symbol-again)
;;            (YaTeX-define-key "\C-b" 'latex-math-preview-beamer-frame)))
;;   (setq latex-math-preview-in-math-mode-p-func 'YaTeX-in-math-mode-p)
;; 
;; This settings uses yatex-specific key binding function `YaTeX-define-key' and
;; usually binds `latex-math-preview-expression' to "C-c p",
;; `latex-math-preview-save-image-file' to "C-c C-p",
;; `latex-math-preview-insert-symbol' to "C-c j",
;; `latex-math-preview-last-symbol-again' to "C-c C-j",
;; and `latex-math-preview-beamer-frame' to "C-c C-b".
;; 
;; The last line of the settings for yatex-mode is the function
;; to distinguish mathematical expressions from normal text.
;; In yatex-mode the function `YaTeX-in-math-mode-p alternatively' is bettern than
;; the function `latex-math-preview-in-math-mode-p'.
;; Therefore, the author recommend that you set the function `YaTeX-in-math-mode-p'
;; to the variable `latex-math-preview-in-math-mode-p-func'.
;; 
;; Of course, in the other major mode to edit latex files, you use local-set-key to define key bindings.
;; 
;;   (add-hook 'latex-mode-hook
;;            '(lambda ()
;;            (local-set-key "\C-cp" 'latex-math-preview-expression)))
;; 
;; ** Paths of Programs
;; latex-math-preview.el uses the commands 'latex', 'dvipng', 'dvips', and so on.
;; If these commands are not in the load paths of system or
;; you want to use the different commands from ones of system default,
;; you need to set the variable `latex-math-preview-command-path-alist'.
;; For example, you can set the variable as the following:
;; 
;;    (setq latex-math-preview-command-path-alist
;;          '((latex . "/usr/bin/latex") (dvipng . "/usr/bin/dvipng") (dvips . "/usr/bin/dvips")))
;; 
;; * Usage
;; ** latex-math-preview-expression
;; If you type M-x `latex-math-preview-expression', a buffer including a preview image pops up.
;; If the cursor points to a mathematical expression, we can preview the expression.
;; If a region is selected with transient-mark on, i.e., with usually backgroud-color changed,
;; we can preview the selected resion.
;; 
;; In the preview buffer, the following binded key is available:
;;  q: exit window of preview buffer
;;  Q: delete preview buffer (the behavior is almost same as pressing 'q')
;;  j: scroll up preview buffer
;;  k: scroll down preview buffer
;;  o: maximize window of preview buffer
;; 
;; ** latex-math-preview-insert-symbol
;; You can insert a LaTeX symbol from the list of symbols if you type
;; M-x `latex-math-preview-insert-symbol'.
;; In the buffer you can select the symbol pointed by the current cursor by pressing RET.
;; Key bindings are displayed in the top of the preview buffer.
;;
;; The images of the symbols are cached in the directory
;; set by `latex-math-preview-cache-directory-for-insertion'.
;; If the cache does not exist, you need to wait for finishing making the images for a while.
;; M-x `latex-math-preview-make-all-cache-images' makes the cache and
;; M-x `latex-math-preview-clear-cache-for-insertion' delete the cache.
;; 
;; M-x `latex-math-preview-insert-symbol' shows the page last opened.
;; C-u M-x `latex-math-preview-insert-symbol' asks you the page that you want to open.
;; M-x `latex-math-preview-last-symbol-again' insert the last inserted symbol.
;; Inside `latex-math-preview-insert-symbol',
;; `latex-math-preview-mathematical-symbol-datasets' or `latex-math-preview-insert-text-symbol'
;; is executed according to the point of the cursor.
;; If you want to display the list of symbols without dependency on the cursor,
;; you can use `latex-math-preview-mathematical-symbol-datasets' or
;; `latex-math-preview-insert-text-symbol' directly.
;; 
;; ** latex-math-preview-save-image-file
;; While `latex-math-preview-expression' displays an images in a buffer,
;; you can save the images as files.
;; If you type M-x `latex-math-preview-save-image-file', you are asked
;; about path of an outputted image.
;; You must input the path of which extention is 'png' or 'eps'.
;; 
;; ** latex-math-preview-beamer-frame
;; If we type M-x `latex-math-preview-beamer-frame'
;; with the cursor in \frame{ ... } or \begin{frame} ... \end{frame},
;; we can preview the page of beamer presentation
;; same as `latex-math-preview-expression'.
;; 
;; * Settings
;; ** LaTeX template
;; latex-math-preview.el makes a temporary LaTeX file and convert it to an image
;; by the commands 'latex', 'dvipng', and so on.
;; The structure of a temporary latex file is the following.
;; -------------------------------------------------------------------
;;   (part of `latex-math-preview-latex-template-header'
;;    the default value is the following)
;;   \documentclass{article}
;;   \pagestyle{empty}
;;   
;;   (part of usepackages
;;    the values of \usepackage searched from current buffer or
;;    `latex-math-preview-latex-usepackage-for-not-tex-file')
;;   
;;   \begin{document}
;;   (some mathematical expressions)
;;   \par
;;   \end{document}
;; -------------------------------------------------------------------
;; 
;; If you want to change the header in the temporary latex files,
;; you set the customized value to the variable `latex-math-preview-latex-template-header'.
;; latex-math-preview searches '\usepackage' in the current buffer and
;; uses its value when making LaTeX files.
;; But when there is no '\usepackage' strings, alternatively
;; the variable `latex-math-preview-latex-usepackage-for-not-tex-file' is used.
;; So you can set your prefered value to
;; the variable `latex-math-preview-latex-usepackage-for-not-tex-file'.
;; When we save image files, the variable `latex-math-preview-template-header-for-save-image' is used.
;; 
;; ** Conversion Process
;; The default value of the variable `latex-math-preview-tex-to-png-for-preview' is
;; 
;;   (defvar latex-math-preview-tex-to-png-for-preview
;;    '(latex dvipng))
;; 
;; This means that to create png images latex-math-preview uses
;; `latex-math-preview-execute-latex' (tex to dvi) and
;; `latex-math-preview-execute-dvipng' (dvi to png) in series.
;; If you use other programs to create png images, please edit this variable.
;; For example, to use platex (tex to dvi), dvipdfmx (dvi to pdf), and gs (pdf to png),
;; 
;;   (defvar latex-math-preview-tex-to-png-for-preview
;;    '(platex dvipdfmx gs-to-png))
;; 
;; The variables `latex-math-preview-tex-to-png-for-save', `latex-math-preview-tex-to-eps-for-save',
;; `latex-math-preview-tex-to-ps-for-save', and `latex-math-preview-beamer-to-png' is similar.
;; The prepared functions we can uses to convert images are
;;  - `latex-math-preview-execute-latex'
;;  - `latex-math-preview-execute-platex'
;;  - `latex-math-preview-execute-pdflatex-to-dvi'
;;  - `latex-math-preview-execute-pdflatex-to-pdf'
;;  - `latex-math-preview-execute-lualatex-to-dvi'
;;  - `latex-math-preview-execute-lualatex-to-pdf'
;;  - `latex-math-preview-execute-dvipdf'
;;  - `latex-math-preview-execute-dvipdfm'
;;  - `latex-math-preview-execute-dvipdfmx'
;;  - `latex-math-preview-execute-dvipng'
;;  - `latex-math-preview-execute-dvips-to-ps'
;;  - `latex-math-preview-execute-dvips-to-eps'
;;  - `latex-math-preview-execute-gs-to-png'
;; 
;; For example, we recommend the following settings to Japanese users, i.e., platex command's user:
;;    (setq-default latex-math-preview-tex-to-png-for-preview '(platex dvipng))
;;    (setq-default latex-math-preview-tex-to-png-for-save '(platex dvipng))
;;    (setq-default latex-math-preview-tex-to-eps-for-save '(platex dvips-to-eps))
;;    (setq-default latex-math-preview-tex-to-ps-for-save '(platex dvips-to-ps))
;;    (setq-default latex-math-preview-beamer-to-png '(platex dvipdfmx gs-to-png))
;; 
;; ** Options of Commands
;; The options of the commands are specified by
;; the variable `latex-math-preview-command-option-alist' and
;; the options for triming margins of images are specified
;; by teh variable `latex-math-preview-command-trim-option-alist'.
;; If you configure the commands, please modify these variables.
;; Because this customize is advanced, the author want you to refer to the source code for details.
;; 
;; The color options of the command 'dvipng' is determined by
;; `latex-math-preview-image-foreground-color' and
;; `latex-math-preview-image-background-color', which define
;; the foreground and background colors of png images respectively.
;; If these variables are nil, these colors are the same as these of the default face.
;; 
;; ** Matching mathematical expression
;; When you execute the function `latex-math-preview-expression',
;; the default settings support the following LaTeX mathematical expressions.
;;  $ ... $
;;  $$ ... $$
;;  \[ ... \]
;;  \begin{math} ... \end{math}
;;  \begin{displaymath} ... \end{displaymath}
;;  \begin{equation} ... \end{equation}
;;  \begin{gather} ... \end{gather}
;;  \begin{align} ... \end{align}
;;  \begin{alignat} ... \end{alignat}
;; 
;; If you want to preview other LaTeX mathematical expressions,
;; please add settings to match them to the variable `latex-math-preview-match-expression'.
;; 
;; ** List of symbols for insertion
;; To change symbol set, you may customize the variable
;; `latex-math-preview-mathematical-symbol-datasets'.
;; The preview buffer of symbol list is popped up with the last opend page.
;; If you always open the same inital page,
;; you set nil to the `latex-math-preview-restore-last-page-of-symbol-list'
;; and the string of the initial page name to
;; the variable `latex-math-preview-initial-page-of-symbol-list'.
;; 
;; This program keep the created images as cache.
;; These images saved in the variable `latex-math-preview-cache-directory-for-insertion'
;; of which default value is "~/.emacs.d/latex-math-preview-cache".
;; If you change the cache directory, please customize this variable.

;;; Change Log:
;; 2019/01/23 version 0.7.3 yamaguchi
;;     New variables `latex-math-preview-select-preview-window' and some bug fixes.
;; 2016/01/05 version 0.7.2 yamaguchi
;;     Support lualatex
;; 2015/12/24 version 0.7.1 yamaguchi
;;     Fix bugs that some caches are not generated
;; 2015/01/01 version 0.7.0 yamaguchi
;;     Merge latex-math-preview-extra-data.el
;; 2015/01/01 version 0.6.4 yamaguchi
;;     To be registered in MELPA
;;     Automatically load extra data if it exists
;; 2013/07/21 version 0.6.3 yamaguchi
;;     A bug fix and revise commentary
;; 2013/07/20 version 0.6.2 yamaguchi
;;     Some bug fixes and minor changes
;; 2011/10/26 version 0.6.1 yamaguchi
;;     Some bug fixes and add `latex-math-preview-set-conversion-command'.
;; 2011/10/22 version 0.6.0 yamaguchi
;;     Some refactorings and add insertion of recent used symbol.
;;     Because changed name of cache file is used we need to clear cache of symbols.
;; 2011/10/09 version 0.5.5 yamaguchi
;;     Support editing and filtering usepackage lines for previewing.
;; 2011/02/07 version 0.5.4 yamaguchi
;;     Support gswin32c.exe for meadow.
;; 2010/09/19 version 0.5.3 yamaguchi
;;     Refactoring.
;; 2010/09/13 version 0.5.2 yamaguchi
;;     Modify to pass byte-compile.
;; 2010/09/13 version 0.5.1 yamaguchi
;;     Some bug fixes.
;; 2010/08/29 version 0.5.0 yamaguchi
;;     Support beamer (add new command `latex-math-preview-beamer-frame').
;;     Remove some functions and variables and add new functions and variables. 
;; 2010/01/20 version 0.4.2 yamaguchi
;;     Add buffer local variable `latex-math-preview-usepackage-cache'
;;     for splitted tex files.
;; 2009/12/09 version 0.4.1 yamaguchi
;;     Add some key binding on latex-math-preview-expression-mode-map.
;; 2009/12/08 version 0.4.0 yamaguchi
;;     Use image-mode when previewing mathematical expressions.
;; 2009/10/18 version 0.3.11 yamaguchi
;;     Change function latex-math-preview-bounds-of-latex-math
;;     to distingush '$$ ... $$' from '$ ... $'.
;; 2009/09/16 version 0.3.10 yamaguchi
;;     Add new functions latex-math-preview-insert-isearch-forward and
;;     latex-math-preview-insert-isearch-backward.
;; 2009/08/27 version 0.3.9 yamaguchi
;;     Fix bug that makes order of usepackage reverse.
;; 2009/08/21 version 0.3.8 yamaguchi
;;     Some bug fixes.
;; 2009/08/14 version 0.3.7 yamaguchi
;;     Bug fix of `latex-math-preview-search-header-usepackage'.
;; 2009/08/13 version 0.3.6 yamaguchi
;;     Bug fix of `latex-math-preview-search-header-usepackage'.
;; 2009/08/12 version 0.3.5 yamaguchi
;;     Display error message of TeX processing.
;; 2009/08/11 version 0.3.4 yamaguchi
;;     Add `latex-math-preview-search-header-usepackage'.
;; 2009/08/08 version 0.3.3 yamaguchi
;;     Add detailed commentary.
;; 2009/08/07 version 0.3.2 yamaguchi
;;     Bug fix.
;; 2009/08/06 version 0.3.1 yamaguchi
;;     New function `latex-math-preview-save-image-file'.
;; 2009/08/06 version 0.3.0 yamaguchi
;;     New function `latex-math-preview-move-to-beginning-of-candidates'.
;;     New function `latex-math-preview-move-to-end-of-candidates'.
;;     New function `latex-math-preview-move-to-current-line-first-item'.
;;     New function `latex-math-preview-move-to-current-line-last-item'.
;;     New function `latex-math-preview-insert-mathematical-symbol'
;;     New function `latex-math-preview-insert-text-symbol'
;;     Extention of `latex-math-preview-expression'.
;;     Remove feature viewing dvi file.
;; 2009/08/04 version 0.2.3 yamaguchi
;;     New function `latex-math-preview-toggle-window-maximization'.
;;     New function `latex-math-preview-last-symbol-again'.
;; 2009/08/03 version 0.2.2 yamaguchi
;;     Change name of function `latex-math-preview-insert-sign' to `latex-math-preview-insert-symbol'.
;;     Add some groups of symbol candidates.
;;     Some bug fixes.
;; 2009/08/02 version 0.2.1 yamaguchi
;;     New command latex-math-preview-next-candidates-for-insertion.
;;     Some adjustments.
;; 2009/08/02 version 0.2.0 yamaguchi
;;     New command latex-math-preview-insert-sign.
;;     Change name of function `latex-math-preview' to `latex-math-preview-expression'.
;;     bug fixes.
;; 2009/07/31 version 0.1.1 yamaguchi
;;     adjust background and foreground colors of png to default face.
;; 2009/07/25 version 0.1.0 yamaguchi
;;     support Meadow3.

;;; Code:

(require 'cl-lib)
(require 'image-mode)
(require 'thingatpt)

;;;###autoload
(defgroup latex-math-preview nil
  "LaTeX Math Preview."
  :prefix "latex-math-preview-"
  :group 'applications
  )

(defvar latex-math-preview-expression-buffer-name
  "*latex-math-preview-expression*"
  "Name of buffer which displays preview image.")

(defvar latex-math-preview-tex-processing-error-buffer-name
  "*latex-math-preview-tex-processing-error*"
  "Name of buffer displaying TeX temporary file which raises error")

(defvar latex-math-preview-error-buffer-major-mode 'latex-mode
  "Major mode for error latex buffer")

(defvar latex-math-preview-insert-symbol-buffer-name
  "*latex-math-preview-candidates*"
  "Name of buffer which displays candidates of LaTeX mathematical symbols.")

(defvar latex-math-preview-temporary-file-prefix
  "temp_latex_math"
  "The prefix name of some temporary files which is produced in making an image.")

(defvar latex-math-preview-cache-directory-for-insertion
  (concat (getenv "HOME") "/.emacs.d/latex-math-preview-cache")
  "Cache directory.")

(defvar latex-math-preview-latex-template-header
  "\\documentclass{article}\n\\pagestyle{empty}\n"
  "Insert string to beginning of temporary latex file to make image.")

(defvar latex-math-preview-latex-usepackage-for-not-tex-file
  '("\\usepackage{amsmath, amssymb, amsthm}")
  "List of strings which are \\usepackage commands.")

(defvar latex-math-preview-template-header-for-save-image
  "\\documentclass{article}\n\\pagestyle{empty}\n"
  "Insert string to beginning of temporary latex file to make image.")

(defvar latex-math-preview-match-expression-remove-formula-number
  '("equation" "gather" "align" "alignat")
  "List of LaTeX enviroments string to remove number of formula when making image file.")

(defvar latex-math-preview-image-foreground-color nil
  "Foreground color of image created by dvipng.")

(defvar latex-math-preview-image-background-color nil
  "Background color of image created by dvipng.")

(defvar latex-math-preview-dvipng-color-option nil
  "The option of dvipng to set colors of background and foreground.
If the value is nil then the colors automatically set from emacs settings.")

(defvar latex-math-preview-previous-window-configuration nil
  "Window configuration before latex-math-preview window is created.
 If the value is not nil then commands of `latex-math-preview-quit-window' etc have effects.")
(make-variable-buffer-local 'latex-math-preview-previous-window-configuration)

(defvar latex-math-preview-current-insert-mode nil
  "Temporary variable of which value is 'math or 'text.")

(defvar latex-math-preview-match-expression
  '(
    ;; \[...\]
    (1 . "[^\\\\]\\(\\\\\\[\\(.\\|\n\\)*?\\\\]\\)")

    ;; \(...\)
    (0 . "\\\\(\\(.\\|\n\\)*?\\\\)")

    ;; \begin{math}...\end{math}
    (0 . "\\\\begin{math}\\(\\(.\\|\n\\)*?\\)\\\\end{math}")

    ;; \begin{displaymath}...\end{displaymath}
    (0 . "\\\\begin{displaymath}\\(\\(.\\|\n\\)*?\\)\\\\end{displaymath}")

    ;; \begin{equation}...\end{equation}
    (0 . "\\\\begin{equation\\(\\|\\*\\)}\\(\\(.\\|\n\\)*?\\)\\\\end{equation\\(\\|\\*\\)}")

    ;; \begin{gather}...\end{gather}
    (0 . "\\\\begin{gather\\(\\|\\*\\)}\\(\\(.\\|\n\\)*?\\)\\\\end{gather\\(\\|\\*\\)}")

    ;; \begin{align}...\end{align}
    (0 . "\\\\begin{align\\(\\|\\*\\)}\\(\\(.\\|\n\\)*?\\)\\\\end{align\\(\\|\\*\\)}")

    ;; \begin{alignat}...\end{alignat}
    (0 . "\\\\begin{alignat\\(\\|\\*\\)}\\(\\(.\\|\n\\)*?\\)\\\\end{alignat\\(\\|\\*\\)}")

    )
  "We use these expressions when extracting a LaTeX mathematical expression.
The elements of this list is the form which is a list of \(integer regular-expression\).
The regular-expression matchs a string including LaTeX mathematical expressions.
The integer is the number to access needed string from regular-expressin.")

(defvar latex-math-preview-list-name-symbol-datasets
  '((math . latex-math-preview-mathematical-symbol-datasets)
    (text . latex-math-preview-text-symbol-datasets))
  "Name of list of datasets.")

(defvar latex-math-preview-select-preview-window t
  "If the value is nil then Emacs will not select the latex-math-preview window when show it.")

;;;###autoload
(cl-defstruct latex-math-preview-symbol source display func args image math)

(defun latex-math-preview-insert-enclosed-symbol (&rest list)
  (insert (car list))
  (save-excursion (insert (nth 2 list))))

(defun latex-math-preview-symbol-make (obj dir &optional math)
  (let ((sym))
    (cond
     ((stringp obj)
      (setq sym (make-latex-math-preview-symbol
		 :source obj :func 'insert :args (list obj))))
     ((listp obj)
      (let ((src (apply 'concat obj)))
	(setq sym (make-latex-math-preview-symbol
		   :source src
		   :func 'latex-math-preview-insert-enclosed-symbol :args obj))))
     ((latex-math-preview-symbol-p obj) (setq sym obj))
     (t (error "Invalid type object")))
    (unless (latex-math-preview-symbol-image sym)
      (setf (latex-math-preview-symbol-image sym)
	    (concat dir "/" (md5 (latex-math-preview-symbol-source sym)) ".png")))
    (unless (latex-math-preview-symbol-math sym)
      (when math (setf (latex-math-preview-symbol-math sym) t)))
    sym))

(defun latex-math-preview-symbol-string (sym)
  (or (latex-math-preview-symbol-display sym) (latex-math-preview-symbol-source sym)))

(defun latex-math-preview-symbol-insert-candidate (sym format-str col line)
  (let ((image-file (latex-math-preview-symbol-image sym)))
    (when (file-exists-p image-file)
      (insert-image (create-image image-file))
      (goto-char (line-end-position))))
  (insert "\t")
  (let ((start-pt (point)))
    (insert (format format-str (latex-math-preview-symbol-string sym)))
    (skip-chars-backward " \t")
    (add-text-properties
     start-pt (point)
     (list 'face 'latex-math-preview-candidate-for-insertion-face
	   'latex-math-preview-symbol sym
	   'latex-math-preview-symbol-column col
	   'latex-math-preview-symbol-line line)))
  (goto-char (line-end-position)))

(defun latex-math-preview-symbol-insert-item (sym)
  (apply (latex-math-preview-symbol-func sym) (latex-math-preview-symbol-args sym)))

(defun latex-math-preview-symbol-tex-source (sym packages)
  (let ((src (latex-math-preview-symbol-source sym)))
    (latex-math-preview-make-temporary-tex-file
     (if (latex-math-preview-symbol-math sym) (concat "$" src "$") src)
     latex-math-preview-latex-template-header packages)))

(defvar latex-math-preview-textcomp-symbol-dataset
  '(("textcomp" ("\\usepackage[T1]{fontenc}" "\\usepackage{textcomp}")
     ("\\textquotestraightbase" "\\textquotestraightdblbase" "\\texttwelveudash"
      "\\textthreequartersemdash" "\\textleftarrow" "\\textrightarrow"
      "\\textblank" "\\textdollar" "\\textquotesingle" "\\textasteriskcentered"
      "\\textdblhyphen" "\\textfractionsolidus"
      "\\textzerooldstyle" "\\textoneoldstyle" "\\texttwooldstyle"
      "\\textthreeoldstyle" "\\textfouroldstyle" "\\textfiveoldstyle"
      "\\textsixoldstyle" "\\textsevenoldstyle" "\\texteightoldstyle"
      "\\textnineoldstyle"
      "\\textlangle" "\\textminus" "\\textrangle" "\\textmho" "\\textbigcircle"
      "\\textohm" "\\textlbrackdbl" "\\textrbrackdbl" "\\textuparrow"
      "\\textdownarrow" "\\textasciigrave" "\\textborn" "\\textdivorced"
      "\\textdied" "\\textleaf" "\\textmarried" "\\textmusicalnote" "\\texttildelow"
      "\\textdblhyphenchar" "\\textasciibreve" "\\textasciicaron" "\\textacutedbl"
      "\\textgravedbl" "\\textdagger" "\\textdaggerdbl" "\\textbardbl"
      "\\textperthousand" "\\textbullet" "\\textcelsius" "\\textdollaroldstyle"
      "\\textcentoldstyle" "\\textflorin" "\\textcolonmonetary" "\\textwon"
      "\\textnaira" "\\textguarani" "\\textpeso" "\\textlira" "\\textrecipe"
      "\\textinterrobang" "\\textinterrobangdown"
      "\\textdong" "\\texttrademark" "\\textpertenthousand" "\\textpilcrow"
      "\\textbaht" "\\textnumero" "\\textdiscount" "\\textestimated"
      "\\textopenbullet" "\\textservicemark" "\\textlquill" "\\textrquill"
      "\\textcent" "\\textsterling" "\\textcurrency" "\\textyen"
      "\\textbrokenbar" "\\textsection" "\\textasciidieresis" "\\textcopyright"
      "\\textordfeminine" "\\textcopyleft" "\\textlnot" "\\textcircledP"
      "\\textregistered" "\\textasciimacron" "\\textdegree" "\\textpm"
      "\\texttwosuperior" "\\textthreesuperior" "\\textasciiacute" "\\textmu"
      "\\textparagraph" "\\textperiodcentered" "\\textreferencemark"
      "\\textonesuperior" "\\textordmasculine" "\\textsurd" "\\textonequarter"
      "\\textonehalf" "\\textthreequarters" "\\texteuro" "\\texttimes" "\\textdiv")))
  "Symbol data for textcomp.sty.")

(defvar latex-math-preview-pifont-zapf-dingbats-symbol-dataset
  '(("Zapf Dingbats" ("\\usepackage{pifont}")
     ("\\ding{\"21}" "\\ding{\"22}" "\\ding{\"23}" "\\ding{\"24}" "\\ding{\"25}"
      "\\ding{\"26}" "\\ding{\"27}" "\\ding{\"28}" "\\ding{\"29}" "\\ding{\"2A}"
      "\\ding{\"2B}" "\\ding{\"2C}" "\\ding{\"2D}" "\\ding{\"2E}" "\\ding{\"2F}"
      "\\ding{\"30}" "\\ding{\"31}" "\\ding{\"32}" "\\ding{\"33}" "\\ding{\"34}"
      "\\ding{\"35}" "\\ding{\"36}" "\\ding{\"37}" "\\ding{\"38}" "\\ding{\"39}"
      "\\ding{\"3A}" "\\ding{\"3B}" "\\ding{\"3C}" "\\ding{\"3D}" "\\ding{\"3E}"
      "\\ding{\"3F}"
      "\\ding{\"40}" "\\ding{\"41}" "\\ding{\"42}" "\\ding{\"43}" "\\ding{\"44}"
      "\\ding{\"45}" "\\ding{\"46}" "\\ding{\"47}" "\\ding{\"48}" "\\ding{\"49}"
      "\\ding{\"4A}" "\\ding{\"4B}" "\\ding{\"4C}" "\\ding{\"4D}" "\\ding{\"4E}"
      "\\ding{\"4F}"
      "\\ding{\"50}" "\\ding{\"51}" "\\ding{\"52}" "\\ding{\"53}" "\\ding{\"54}"
      "\\ding{\"55}" "\\ding{\"56}" "\\ding{\"57}" "\\ding{\"58}" "\\ding{\"59}"
      "\\ding{\"5A}" "\\ding{\"5B}" "\\ding{\"5C}" "\\ding{\"5D}" "\\ding{\"5E}"
      "\\ding{\"5F}"
      "\\ding{\"60}" "\\ding{\"61}" "\\ding{\"62}" "\\ding{\"63}" "\\ding{\"64}"
      "\\ding{\"65}" "\\ding{\"66}" "\\ding{\"67}" "\\ding{\"68}" "\\ding{\"69}"
      "\\ding{\"6A}" "\\ding{\"6B}" "\\ding{\"6C}" "\\ding{\"6D}" "\\ding{\"6E}"
      "\\ding{\"6F}"
      "\\ding{\"70}" "\\ding{\"71}" "\\ding{\"72}" "\\ding{\"73}" "\\ding{\"74}"
      "\\ding{\"75}" "\\ding{\"76}" "\\ding{\"77}" "\\ding{\"78}" "\\ding{\"79}"
      "\\ding{\"7A}" "\\ding{\"7B}" "\\ding{\"7C}" "\\ding{\"7D}" "\\ding{\"7E}"
      "\\ding{\"A1}" "\\ding{\"A2}" "\\ding{\"A3}" "\\ding{\"A4}" "\\ding{\"A5}"
      "\\ding{\"A6}" "\\ding{\"A7}" "\\ding{\"A8}" "\\ding{\"A9}" "\\ding{\"AA}"
      "\\ding{\"AB}" "\\ding{\"AC}" "\\ding{\"AD}" "\\ding{\"AE}" "\\ding{\"AF}"
      "\\ding{\"B0}" "\\ding{\"B1}" "\\ding{\"B2}" "\\ding{\"B3}" "\\ding{\"B4}"
      "\\ding{\"B5}" "\\ding{\"B6}" "\\ding{\"B7}" "\\ding{\"B8}" "\\ding{\"B9}"
      "\\ding{\"BA}" "\\ding{\"BB}" "\\ding{\"BC}" "\\ding{\"BD}" "\\ding{\"BE}"
      "\\ding{\"BF}"
      "\\ding{\"C0}" "\\ding{\"C1}" "\\ding{\"C2}" "\\ding{\"C3}" "\\ding{\"C4}"
      "\\ding{\"C5}" "\\ding{\"C6}" "\\ding{\"C7}" "\\ding{\"C8}" "\\ding{\"C9}"
      "\\ding{\"CA}" "\\ding{\"CB}" "\\ding{\"CC}" "\\ding{\"CD}" "\\ding{\"CE}"
      "\\ding{\"CF}"
      "\\ding{\"D0}" "\\ding{\"D1}" "\\ding{\"D2}" "\\ding{\"D3}" "\\ding{\"D4}"
      "\\ding{\"D5}" "\\ding{\"D6}" "\\ding{\"D7}" "\\ding{\"D8}" "\\ding{\"D9}"
      "\\ding{\"DA}" "\\ding{\"DB}" "\\ding{\"DC}" "\\ding{\"DD}" "\\ding{\"DE}"
      "\\ding{\"DF}"
      "\\ding{\"E0}" "\\ding{\"E1}" "\\ding{\"E2}" "\\ding{\"E3}" "\\ding{\"E4}"
      "\\ding{\"E5}" "\\ding{\"E6}" "\\ding{\"E7}" "\\ding{\"E8}" "\\ding{\"E9}"
      "\\ding{\"EA}" "\\ding{\"EB}" "\\ding{\"EC}" "\\ding{\"ED}" "\\ding{\"EE}"
      "\\ding{\"EF}"
      "\\ding{\"F1}" "\\ding{\"F2}" "\\ding{\"F3}" "\\ding{\"F4}" "\\ding{\"F5}"
      "\\ding{\"F6}" "\\ding{\"F7}" "\\ding{\"F8}" "\\ding{\"F9}" "\\ding{\"FA}"
      "\\ding{\"FB}" "\\ding{\"FC}" "\\ding{\"FD}" "\\ding{\"FE}")))
  "Symbol data for Zapf Dingbats in pifont.sty")

(defvar latex-math-preview-pifont-symbol-fonts-symbol-dataset
  '(("Symbol font" ("\\usepackage{pifont}")
     ("\\Pisymbol{psy}{\"21}" "\\Pisymbol{psy}{\"22}"
      "\\Pisymbol{psy}{\"23}" "\\Pisymbol{psy}{\"24}" "\\Pisymbol{psy}{\"25}"
      "\\Pisymbol{psy}{\"26}" "\\Pisymbol{psy}{\"27}" "\\Pisymbol{psy}{\"28}"
      "\\Pisymbol{psy}{\"29}" "\\Pisymbol{psy}{\"2A}" "\\Pisymbol{psy}{\"2B}"
      "\\Pisymbol{psy}{\"2C}" "\\Pisymbol{psy}{\"2D}" "\\Pisymbol{psy}{\"2E}"
      "\\Pisymbol{psy}{\"2F}"
      "\\Pisymbol{psy}{\"30}" "\\Pisymbol{psy}{\"31}" "\\Pisymbol{psy}{\"32}"
      "\\Pisymbol{psy}{\"33}" "\\Pisymbol{psy}{\"34}" "\\Pisymbol{psy}{\"35}"
      "\\Pisymbol{psy}{\"36}" "\\Pisymbol{psy}{\"37}" "\\Pisymbol{psy}{\"38}"
      "\\Pisymbol{psy}{\"39}" "\\Pisymbol{psy}{\"3A}" "\\Pisymbol{psy}{\"3B}"
      "\\Pisymbol{psy}{\"3C}" "\\Pisymbol{psy}{\"3D}" "\\Pisymbol{psy}{\"3E}"
      "\\Pisymbol{psy}{\"3F}"
      "\\Pisymbol{psy}{\"40}" "\\Pisymbol{psy}{\"41}" "\\Pisymbol{psy}{\"42}"
      "\\Pisymbol{psy}{\"43}" "\\Pisymbol{psy}{\"44}" "\\Pisymbol{psy}{\"45}"
      "\\Pisymbol{psy}{\"46}" "\\Pisymbol{psy}{\"47}" "\\Pisymbol{psy}{\"48}"
      "\\Pisymbol{psy}{\"49}" "\\Pisymbol{psy}{\"4A}" "\\Pisymbol{psy}{\"4B}"
      "\\Pisymbol{psy}{\"4C}" "\\Pisymbol{psy}{\"4D}" "\\Pisymbol{psy}{\"4E}"
      "\\Pisymbol{psy}{\"4F}"
      "\\Pisymbol{psy}{\"50}" "\\Pisymbol{psy}{\"51}" "\\Pisymbol{psy}{\"52}"
      "\\Pisymbol{psy}{\"53}" "\\Pisymbol{psy}{\"54}" "\\Pisymbol{psy}{\"55}"
      "\\Pisymbol{psy}{\"56}" "\\Pisymbol{psy}{\"57}" "\\Pisymbol{psy}{\"58}"
      "\\Pisymbol{psy}{\"59}" "\\Pisymbol{psy}{\"5A}" "\\Pisymbol{psy}{\"5B}"
      "\\Pisymbol{psy}{\"5C}" "\\Pisymbol{psy}{\"5D}" "\\Pisymbol{psy}{\"5E}"
      "\\Pisymbol{psy}{\"5F}"
      "\\Pisymbol{psy}{\"60}" "\\Pisymbol{psy}{\"61}" "\\Pisymbol{psy}{\"62}"
      "\\Pisymbol{psy}{\"63}" "\\Pisymbol{psy}{\"64}" "\\Pisymbol{psy}{\"65}"
      "\\Pisymbol{psy}{\"66}" "\\Pisymbol{psy}{\"67}" "\\Pisymbol{psy}{\"68}"
      "\\Pisymbol{psy}{\"69}" "\\Pisymbol{psy}{\"6A}" "\\Pisymbol{psy}{\"6B}"
      "\\Pisymbol{psy}{\"6C}" "\\Pisymbol{psy}{\"6D}" "\\Pisymbol{psy}{\"6E}"
      "\\Pisymbol{psy}{\"6F}"
      "\\Pisymbol{psy}{\"70}" "\\Pisymbol{psy}{\"71}" "\\Pisymbol{psy}{\"72}"
      "\\Pisymbol{psy}{\"73}" "\\Pisymbol{psy}{\"74}" "\\Pisymbol{psy}{\"75}"
      "\\Pisymbol{psy}{\"76}" "\\Pisymbol{psy}{\"77}" "\\Pisymbol{psy}{\"78}"
      "\\Pisymbol{psy}{\"79}" "\\Pisymbol{psy}{\"7A}" "\\Pisymbol{psy}{\"7B}"
      "\\Pisymbol{psy}{\"7C}" "\\Pisymbol{psy}{\"7D}" "\\Pisymbol{psy}{\"7E}"
      "\\Pisymbol{psy}{\"A1}" "\\Pisymbol{psy}{\"A2}"
      "\\Pisymbol{psy}{\"A3}" "\\Pisymbol{psy}{\"A4}" "\\Pisymbol{psy}{\"A5}"
      "\\Pisymbol{psy}{\"A6}" "\\Pisymbol{psy}{\"A7}" "\\Pisymbol{psy}{\"A8}"
      "\\Pisymbol{psy}{\"A9}" "\\Pisymbol{psy}{\"AA}" "\\Pisymbol{psy}{\"AB}"
      "\\Pisymbol{psy}{\"AC}" "\\Pisymbol{psy}{\"AD}" "\\Pisymbol{psy}{\"AE}"
      "\\Pisymbol{psy}{\"AF}"
      "\\Pisymbol{psy}{\"B0}" "\\Pisymbol{psy}{\"B1}" "\\Pisymbol{psy}{\"B2}"
      "\\Pisymbol{psy}{\"B3}" "\\Pisymbol{psy}{\"B4}" "\\Pisymbol{psy}{\"B5}"
      "\\Pisymbol{psy}{\"B6}" "\\Pisymbol{psy}{\"B7}" "\\Pisymbol{psy}{\"B8}"
      "\\Pisymbol{psy}{\"B9}" "\\Pisymbol{psy}{\"BA}" "\\Pisymbol{psy}{\"BB}"
      "\\Pisymbol{psy}{\"BC}" "\\Pisymbol{psy}{\"BD}" "\\Pisymbol{psy}{\"BE}"
      "\\Pisymbol{psy}{\"BF}"
      "\\Pisymbol{psy}{\"C0}" "\\Pisymbol{psy}{\"C1}" "\\Pisymbol{psy}{\"C2}"
      "\\Pisymbol{psy}{\"C3}" "\\Pisymbol{psy}{\"C4}" "\\Pisymbol{psy}{\"C5}"
      "\\Pisymbol{psy}{\"C6}" "\\Pisymbol{psy}{\"C7}" "\\Pisymbol{psy}{\"C8}"
      "\\Pisymbol{psy}{\"C9}" "\\Pisymbol{psy}{\"CA}" "\\Pisymbol{psy}{\"CB}"
      "\\Pisymbol{psy}{\"CC}" "\\Pisymbol{psy}{\"CD}" "\\Pisymbol{psy}{\"CE}"
      "\\Pisymbol{psy}{\"CF}"
      "\\Pisymbol{psy}{\"D0}" "\\Pisymbol{psy}{\"D1}" "\\Pisymbol{psy}{\"D2}"
      "\\Pisymbol{psy}{\"D3}" "\\Pisymbol{psy}{\"D4}" "\\Pisymbol{psy}{\"D5}"
      "\\Pisymbol{psy}{\"D6}" "\\Pisymbol{psy}{\"D7}" "\\Pisymbol{psy}{\"D8}"
      "\\Pisymbol{psy}{\"D9}" "\\Pisymbol{psy}{\"DA}" "\\Pisymbol{psy}{\"DB}"
      "\\Pisymbol{psy}{\"DC}" "\\Pisymbol{psy}{\"DD}" "\\Pisymbol{psy}{\"DE}"
      "\\Pisymbol{psy}{\"DF}"
      "\\Pisymbol{psy}{\"E0}" "\\Pisymbol{psy}{\"E1}" "\\Pisymbol{psy}{\"E2}"
      "\\Pisymbol{psy}{\"E3}" "\\Pisymbol{psy}{\"E4}" "\\Pisymbol{psy}{\"E5}"
      "\\Pisymbol{psy}{\"E6}" "\\Pisymbol{psy}{\"E7}" "\\Pisymbol{psy}{\"E8}"
      "\\Pisymbol{psy}{\"E9}" "\\Pisymbol{psy}{\"EA}" "\\Pisymbol{psy}{\"EB}"
      "\\Pisymbol{psy}{\"EC}" "\\Pisymbol{psy}{\"ED}" "\\Pisymbol{psy}{\"EE}"
      "\\Pisymbol{psy}{\"EF}"
      "\\Pisymbol{psy}{\"F1}" "\\Pisymbol{psy}{\"F2}"
      "\\Pisymbol{psy}{\"F3}" "\\Pisymbol{psy}{\"F4}" "\\Pisymbol{psy}{\"F5}"
      "\\Pisymbol{psy}{\"F6}" "\\Pisymbol{psy}{\"F7}" "\\Pisymbol{psy}{\"F8}"
      "\\Pisymbol{psy}{\"F9}" "\\Pisymbol{psy}{\"FA}" "\\Pisymbol{psy}{\"FB}"
      "\\Pisymbol{psy}{\"FC}" "\\Pisymbol{psy}{\"FD}" "\\Pisymbol{psy}{\"FE}")))
  "Symbol data for syymbol fonts in pifont.sty.")

(defvar latex-math-preview-text-symbol-datasets
  '(("RecentUsed" . latex-math-preview-symbol-recent-used-text)
    ("SpecialCharacter"
     ("special character" nil
      ("\\#" "\\$" "\\%" "\\&" "\\_" "\\{" "\\}" "\\S" "\\P" "\\dag" "\\ddag"
       "\\copyright" "\\pounds" "\\oe" "\\OE" "\\ae" "\\AE" "\\aa" "\\AA"
       "\\o" "\\O" "\\l" "\\L" "\\ss" "?`" "!`" "\\i"
       "\\j" "`" "'" "``"
       "''" "*" "``\\,'" "'\\,``" "-" "--" "---" "\\textregistered"
       "\\texttrademark" "\\textvisiblespace" "\\textbackslash"
       "\\textasciitilde" "\\textasciicircum" ("\\textcircled{" "s" "}")
       ))
     ("special charactor (2)" ("\\usepackage[T1]{fontenc}")
      ("\\DH" "\\dh" "\\DJ" "\\dj" "\\NG" "\\ng" "\\TH" "\\th"
       "\\guillemotleft" "\\guilsinglleft" "\\quotedblbase" "\\textquotedbl"
       "\\guillemotright" "\\guilsinglright" "\\quotesinglbase")))
    ("AccentText"
     ("accent (1)" nil
      (("\\`{" "o" "}") ("\\'{" "o" "}") ("\\^{" "o" "}") ("\\\"{" "o" "}")
       ("\\~{" "o" "}") ("\\={" "o" "}") ("\\.{" "o" "}") ("\\u{" "o" "}")
       ("\\v{" "o" "}") ("\\H{" "o" "}") ("\\t{" "oo" "}") ("\\c{" "o" "}")
       ("\\d{" "o" "}") ("\\b{" "o" "}") ("\\r{" "a" "}")
       ))
     ("accent (2)" ("\\usepackage[T1]{fontenc}")
      (("\\k{" "a" "}"))))
    ("Logo"
     ("logo (1)" nil
      ("\\TeX" "\\LaTeX" "\\LaTeXe"))
     ("logo (2)" ("\\usepackage{mflogo}")
      ("\\MF" "\\MP")))
    ("Textcomp" . latex-math-preview-textcomp-symbol-dataset)
    ("PifontZapfDingbats" . latex-math-preview-pifont-zapf-dingbats-symbol-dataset)
    ("PifontSymbolFonts" . latex-math-preview-pifont-symbol-fonts-symbol-dataset))
  "List of candidates for insertion of symbol.
The elements is the data having the following structure.
\(\"unique id\" \(\"usepackage command 1\" \"usepackage command 2\" ...\)
\(data of symbol candidates\)\)

Each data of symbol candidates is string or list. In the case of string,
just insert it in the buffer. If the data is list, list must have three strings,
that is \(StringA, StringB StringC\). Then, insert the composition
StringA and StringB.")

(defvar latex-math-preview-mathematical-symbol-datasets
  `(("RecentUsed" . latex-math-preview-symbol-recent-used-math)
    ("DelimitersArrows"
     ("delimiters" nil
      (("(" "x" ")") ("[" "x" "]") ("\\{" "x" "\\}")
       ("\\lfloor " "x" " \\rfloor") ("\\lceil " "x" " \\rceil")
       ("\\langle " "x" " \\rangle")
       "\\backslash" "\\|" "\\uparrow" "\\Uparrow" "\\downarrow" "\\Downarrow"
       "\\updownarrow" "\\Updownarrow"))
     ("arrows" nil
      ("\\gets" "\\Leftarrow" "\\to" "\\Rightarrow"
       ;; omit "\\leftarrow" and "\\rightarrow"
       "\\leftrightarrow" "\\Leftrightarrow" "\\mapsto" "\\hookleftarrow"
       "\\leftharpoonup" "\\leftharpoondown" "\\longleftarrow" "\\Longleftarrow"
       "\\longleftrightarrow" "\\Longleftrightarrow" "\\longmapsto"
       "\\hookrightarrow" "\\rightharpoonup" "\\rightharpoondown"
       "\\iff" "\\nearrow" "\\searrow" "\\swarrow" "\\nwarrow"
       "\\rightleftharpoons")))
    ("GreekLetters"
     ("greek letters" nil
      ("\\alpha" "\\beta" "\\gamma" "\\delta" "\\epsilon" "\\zeta" "\\eta"
       "\\theta" "\\iota" "\\kappa" "\\lambda" "\\mu" "\\nu" "\\xi" "\\pi"
       "\\rho" "\\sigma" "\\tau" "\\upsilon" "\\phi" "\\chi" "\\psi" "\\omega"
       "\\varepsilon" "\\vartheta" "\\varpi" "\\varrho" "\\varsigma" "\\varphi"
       "\\Gamma" "\\Delta" "\\Theta" "\\Lambda" "\\Xi" "\\Pi" "\\Sigma"
       "\\Upsilon" "\\Phi" "\\Psi" "\\Omega"))
     ("italic greek letters" ("\\usepackage{amsmath}")
      ("\\varGamma" "\\varDelta" "\\varTheta" "\\varLambda" "\\varXi" "\\varPi"
       "\\varSigma" "\\varUpsilon" "\\varPhi" "\\varPsi" "\\varOmega")))
    ("BinaryOperator1"
     ("binary operators (1)" nil
      ("\\pm" "\\mp" "\\times" "\\div"  "\\ast" "\\star" "\\circ" "\\bullet"
       "\\cdot" "\\cap" "\\cup" "\\uplus" "\\sqcap" "\\sqcup" "\\vee" "\\wedge"
       "\\setminus" "\\wr" "\\diamond" "\\bigtriangleup" "\\bigtriangledown"
       "\\triangleleft" "\\triangleright" "\\oplus" "\\ominus" "\\otimes"
       "\\oslash" "\\odot" "\\bigcirc" "\\dagger" "\\ddagger" "\\amalg")))
    ("RelationalOperator1"
     ("relational operators (1)" nil
      ("\\le" "\\prec" "\\preceq" "\\ll" "\\subset" "\\subseteq" "\\vdash"
       "\\in" "\\notin" "\\ge" "\\succ" "\\succeq" "\\gg" "\\supset" "\\supseteq"
       "\\sqsupseteq" "\\dashv" "\\ni"
       ;; omit "\\leq" and "geq" because this is the same as "\\le" and "\\ge", respectively.
       "\\equiv" "\\sim" "\\simeq" "\\asymp" "\\approx" "\\cong" "\\neq"
       "\\doteq" "\\propto" "\\models" "\\perp" "\\mid" "\\parallel" "\\bowtie"
       "\\smile" "\\frown"
       "\\not\\equiv")))
    ("BinaryOperator2"
     ("binary operators (2)" ("\\usepackage{amssymb}")
      ("\\boxdot" "\\boxplus" "\\centerdot" "\\boxminus" "\\veebar" "\\barwedge"
       "\\doublebarwedge" "\\Cup" "\\Cap" "\\curlywedge" "\\curlyvee"
       "\\leftthreetimes" "\\rightthreetimes" "\\dotplus" "\\intercal"
       "\\circledcirc" "\\circledast" "\\circleddash" "\\divideontimes" "\\lessdot"
       "\\gtrdot" "\\ltimes" "\\rtimes" "\\smallsetminus")))
    ("RelationalOperator2"
     ("relational operators (2)" ("\\usepackage{amssymb}")
      ("\\circlearrowright" "\\circlearrowleft" "\\rightleftharpoons"
       "\\leftrightharpoons" "\\Vdash" "\\Vvdash" "\\vDash" "\\twoheadrightarrow"
       "\\twoheadleftarrow" "\\leftleftarrows" "\\rightrightarrows" "\\upuparrows"
       "\\downdownarrows" "\\upharpoonright" "\\downharpoonright" "\\upharpoonleft"
       "\\downharpoonleft" "\\rightarrowtail" "\\leftarrowtail" "\\rightleftarrows"
       "\\Lsh" "\\Rsh" "\\rightsquigarrow" "\\leftrightsquigarrow" "\\looparrowleft"
       "\\looparrowright" "\\circeq" "\\succsim" "\\gtrsim" "\\gtrapprox"
       "\\multimap" "\\therefore" "\\because" "\\doteqdot" "\\triangleq" "\\precsim"
       "\\lesssim" "\\lessapprox" "\\eqslantless" "\\eqslantgtr" "\\curlyeqprec"
       "\\curlyeqsucc")))
    ("RelationalOperator3"
     ("relational operators (3)" ("\\usepackage{amssymb}")
      ("\\preccurlyeq" "\\leqq" "\\leqslant" "\\lessgtr" "\\risingdotseq"
       "\\fallingdotseq" "\\succcurlyeq" "\\geqq" "\\geqslant" "\\gtrless"
       "\\sqsubset" "\\sqsupset" "\\vartriangleright" "\\vartriangleleft"
       "\\trianglerighteq" "\\trianglelefteq" "\\between" "\\blacktriangleright"
       "\\blacktriangleleft" "\\vartriangle" "\\eqcirc" "\\lesseqgtr" "\\gtreqless"
       "\\lesseqqgtr" "\\gtreqqless" "\\Rrightarrow" "\\Lleftarrow" "\\varpropto"
       "\\smallsmile" "\\smallfrown" "\\Subset" "\\Supset" "\\subseteqq"
       "\\supseteqq" "\\bumpeq" "\\Bumpeq" "\\lll" "\\ggg" "\\pitchfork"
       "\\backsim" "\\backsimeq")))
    ("RelationalOperator4"
     ("relational operators (4)" ("\\usepackage{amssymb}")
      ("\\lvertneqq" "\\gvertneqq" "\\nleq" "\\ngeq" "\\nless" "\\ngtr" "\\nprec"
       "\\nsucc" "\\lneqq" "\\gneqq" "\\nleqslant" "\\ngeqslant" "\\lneq" "\\gneq"
       "\\npreceq" "\\nsucceq" "\\precnsim" "\\succnsim" "\\lnsim" "\\gnsim"
       "\\nleqq" "\\ngeqq" "\\precneqq" "\\succneqq" "\\precnapprox" "\\succnapprox"
       "\\lnapprox" "\\gnapprox" "\\nsim" "\\ncong" "\\varsubsetneq" "\\varsupsetneq"
       "\\nsubseteqq" "\\nsupseteqq" "\\subsetneqq" "\\supsetneqq" "\\varsubsetneqq"
       "\\varsupsetneqq" "\\subsetneq" "\\supsetneq" "\\nsubseteq" "\\nsupseteq"
       "\\nparallel" "\\nmid" "\\nshortmid" "\\nshortparallel" "\\nvdash"
       "\\nVdash" "\\nvDash" "\\nVDash" "\\ntrianglerighteq" "\\ntrianglelefteq"
       "\\ntriangleleft" "\\ntriangleright" "\\nleftarrow" "\\nLeftarrow"
       "\\nRightarrow" "\\nLeftrightarrow" "\\nleftrightarrow" "\\eqsim"
       "\\shortmid" "\\shortparallel" "\\thicksim" "\\thickapprox" "\\approxeq"
       "\\succapprox" "\\precapprox" "\\curvearrowleft" "\\curvearrowright"
       "\\backepsilon")))
    ("BigSymbolsIntegralDots"
     ("big symbols" nil
      ("\\sum" "\\prod" "\\coprod" "\\int" "\\oint" "\\bigcap" "\\bigcup"
       "\\bigsqcup" "\\bigvee" "\\bigwedge" "\\bigodot" "\\bigotimes"
       "\\bigoplus" "\\biguplus"))
     ("integral" ("\\usepackage{amsmath}" "\\usepackage{amssymb}")
      ("\\int" "\\iint" "\\iiint" "\\iiiint" "\\idotsint"))
     ("dots" ("\\usepackage{amsmath}" "\\usepackage{amssymb}")
      ("\\dots"
       ,(make-latex-math-preview-symbol :source "A \\dotsc Z" :func 'insert :args '("\\dotsc"))
       ,(make-latex-math-preview-symbol :source "A \\dotsb Z" :func 'insert :args '("\\dotsb"))
       ,(make-latex-math-preview-symbol :source "A \\dotsm Z" :func 'insert :args '("\\dotsm"))
       ,(make-latex-math-preview-symbol :source "A \\dotsi Z" :func 'insert :args '("\\dotsi")))))
    ("MiscellaneousSymbols"
     ("miscellaneous" nil
      ("\\aleph" "\\hbar" "\\imath" "\\jmath" "\\ell" "\\wp" "\\Re" "\\Im"
       "\\partial" "\\infty" "\\prime" "\\emptyset" "\\nabla" "\\surd"
       "\\top" "\\bot" "\\angle" "\\triangle" "\\forall" "\\exists"
       "\\neg" "\\flat" "\\natural" "\\sharp" "\\clubsuit" "\\diamondsuit"
       "\\heartsuit" "\\spadesuit"))
     ("other symbols" ("\\usepackage{amssymb}")
      ("\\square" "\\blacksquare" "\\lozenge" "\\blacklozenge" "\\backprime"
       "\\bigstar" "\\blacktriangledown" "\\blacktriangle" "\\triangledown"
       "\\angle" "\\measuredangle" "\\sphericalangle" "\\circledS" "\\complement"
       "\\diagup" "\\diagdown" "\\varnothing" "\\nexists" "\\Finv" "\\Game"
       "\\mho" "\\eth" "\\beth" "\\gimel" "\\daleth" "\\digamma"
       "\\varkappa" "\\Bbbk" "\\hslash" "\\hbar")))
    ("Functions"
     ("often used" nil
      (("\\frac{" "x" "}{y}") ("" "x" "^{n}") "\\sum_{i=0}^{\\infty}"
       ("\\sqrt{" "x" "}") ("\\sqrt[" "3" "]{x}")))
     ("fraction" ("\\usepackage{amsmath}" "\\usepackage{amssymb}")
      (("\\tfrac{" "a" "}{b}") ("\\dfrac{" "a" "}{b}") ("\\cfrac{" "a" "}{b}")
       ("\\binom{" "a" "}{b}")))
     ("functions" nil
      ("\\arccos" "\\arcsin" "\\arctan" "\\arg" "\\cos" "\\cosh" "\\cot" "\\coth"
       "\\csc" "\\deg" "\\det" "\\dim" "\\exp" "\\gcd" "\\hom" "\\inf" "\\ker"
       "\\lg" "\\lim" "\\liminf" "\\limsup" "\\ln" "\\log" "\\max" "\\min"
       "\\Pr" "\\sec" "\\sin" "\\sinh" "\\sup" "\\tan" "\\tanh"
       "\\bmod" "\\pmod")))
    ("AccentMath"
     ("accent (1)" nil
      (("\\hat{" "a" "}") ("\\check{" "a" "}") ("\\breve{" "a" "}")
       ("\\acute{" "a" "}") ("\\grave{" "a" "}") ("\\tilde{" "a" "}")
       ("\\bar{" "a" "}") ("\\vec{" "a" "}") ("\\dot{" "a" "}") ("\\ddot{" "a" "}")))
     ("accent (2)" ("\\usepackage{amsmath}" "\\usepackage{amssymb}")
      (("\\Hat{" "A" "}") ("\\Dot{" "A" "}") ("\\Check{" "A" "}")
       ("\\Ddot{" "A" "}") ("\\Tilde{" "A" "}") ("\\Breve{" "A" "}")
       ("\\Acute{" "A" "}") ("\\Bar{" "A" "}") ("\\Vec{" "A" "}")
       ("\\dddot{" "x" "}") ("\\ddddot{" "x" "}"))))
    ("Decoration"
     ("decoration 1" nil
      (("\\overline{" "xy" "}") ("\\underline{" "xy" "}") ("\\widehat{" "xy" "}")
       ("\\widetilde{" "xy" "}") ("\\overbrace{" "xy" "}")
       ("\\underbrace{" "xy" "}") ("\\overrightarrow{" "\\mathrm{OA}" "}")
       ("\\overleftarrow{" "\\mathrm{OA}" "}") ("\\stackrel{" "f" "}{\\to}")
       "\\stackrel{\\mathrm{def}}{=}"))
     ("decoration 2" ("\\usepackage{amsmath}" "\\usepackage{amssymb}")
      (("\\overleftrightarrow{" "A" "}") ("\\underleftrightarrow{" "A" "}")
       ("\\xrightarrow{" "\\text{text}" "}") ("\\xrightarrow[" "abc" "]{}")
       ("\\xleftarrow{" "\\text{text}" "}") ("\\xleftarrow[" "abc" "]{}"))))
    ("Typefaces"
     ("typefaces (1)" nil
      (("\\mathrm{" "abcdefghABCDEFGH" "}") ("\\mathbf{" "abcdefghABCDEFGH" "}")
       ("\\mathit{" "abcdefghABCDEFGH" "}") ("\\mathcal{" "abcdefghABCDEFGH" "}")
       ("\\mathsf{" "abcdefghABCDEFGH" "}") ("\\mathtt{" "abcdefghABCDEFGH" "}")))
     ("typefaces (2)" ("\\usepackage{amssymb}")
      (("\\mathfrak{" "abcdefghABCDEFGH" "}") ("\\mathbb{" "abcdefghABCDEFGH" "}"))))
    )
  "List of candidates for insertion of LaTeX mathematical symbol.
For data structure, refer to `latex-math-preview-text-symbol-datasets'")

(defvar latex-math-preview-always-maximize-window nil
  "Always maximize preview window for `latex-math-preview-insert-symbol' if non-nil.")

(defvar latex-math-preview-restore-last-page-of-symbol-list t
  "Restore last page of symbol list at next insertion
 if this `latex-math-preview-restore-last-page-of-symbol-list' is non-nil.")

(defvar latex-math-preview-recent-inserted-symbol-number 30)

(defvar latex-math-preview-recent-inserted-symbol '((math . nil) (text . nil))
  "Inserted last symbol.")

(defvar latex-math-preview-initial-page-of-symbol-list
  `((math . ,(car (nth 0 latex-math-preview-mathematical-symbol-datasets)))
    (text . ,(car (nth 0 latex-math-preview-text-symbol-datasets))))
  "Page of symbol list which is displayed initially.")

(defvar latex-math-preview-current-page-of-symbol-list '((math . nil) (text . nil))
  "Page of symbol list on present buffer displaying mathematical symbols.")

(defvar latex-math-preview-information-line-number nil
  "Temporary variable. List of line numbers at which various information is descripted.")

(defface latex-math-preview-candidate-for-insertion-face
  '((t (:foreground "dark orange")))
  "Face for notations of LaTeX mathematical symbol.")

(defface latex-math-preview-key-for-insertion-face
  '((t (:foreground "dodger blue")))
  "Face for notations of LaTeX mathematical symbol.")

(defvar latex-math-preview-selection-face-for-insertion 'highlight
  "Face for currently selected item.")

(defvar latex-math-preview-selection-overlay-for-insertion nil
  "Overlay for highlighting currently selected item.")

(defvar latex-math-preview-not-delete-tmpfile nil
  "Not delete temporary files and directory if this value is true. Mainly for debugging.")

(defvar latex-math-preview-dvipng-log-buffer nil
  "Buffer name for output by dvipng. Mainly for debugging.")

(defvar latex-math-preview-in-math-mode-p-func 'latex-math-preview-in-math-mode-p
  "Symbol of function is used for determining whether cursor is in mathematical expression.
If you use YaTeX mode then the recommended value of this variable is YaTeX-in-math-mode-p.")

(define-derived-mode latex-math-preview-expression-mode image-mode "LaTeXPreview"
  "Major mode for latex-math-preview-expression. This mode is derived from image-mode."
  (define-key latex-math-preview-expression-mode-map "n" 'next-line)
  (define-key latex-math-preview-expression-mode-map "p" 'previous-line)
  (define-key latex-math-preview-expression-mode-map "f" 'forward-char)
  (define-key latex-math-preview-expression-mode-map "b" 'backward-char)
  (define-key latex-math-preview-expression-mode-map "j" 'next-line)
  (define-key latex-math-preview-expression-mode-map "k" 'previous-line)
  (define-key latex-math-preview-expression-mode-map "l" 'forward-char)
  (define-key latex-math-preview-expression-mode-map "h" 'backward-char)
  (define-key latex-math-preview-expression-mode-map "o" 'delete-other-windows)
  (define-key latex-math-preview-expression-mode-map "g" 'latex-math-preview-quit-window)
  (define-key latex-math-preview-expression-mode-map "q" 'latex-math-preview-quit-window)
  (define-key latex-math-preview-expression-mode-map "Q" 'latex-math-preview-delete-buffer))

(defvar latex-math-preview-insert-symbol-map nil
  "Keymap for insertion mode of latex-math-preview-insert-symbol.")

(or latex-math-preview-insert-symbol-map
    (let ((map (make-sparse-keymap)))
      (define-key map (kbd "q") 'latex-math-preview-quit-window)
      (define-key map (kbd "Q") 'latex-math-preview-delete-buffer)
      (define-key map (kbd "g") 'latex-math-preview-quit-window)
      (define-key map (kbd "o") 'latex-math-preview-toggle-window-maximization)
      (define-key map (kbd "c") 'latex-math-preview-symbols-of-other-page)
      (define-key map (kbd "j") 'latex-math-preview-move-to-downward-item)
      (define-key map (kbd "k") 'latex-math-preview-move-to-upward-item)
      (define-key map (kbd "l") 'latex-math-preview-move-to-right-item)
      (define-key map (kbd "h") 'latex-math-preview-move-to-left-item)
      (define-key map (kbd "a") 'latex-math-preview-move-to-current-line-first-item)
      (define-key map (kbd "e") 'latex-math-preview-move-to-current-line-last-item)
      (define-key map (kbd "C-a") 'latex-math-preview-move-to-current-line-first-item)
      (define-key map (kbd "C-e") 'latex-math-preview-move-to-current-line-last-item)
      (define-key map (kbd "n") 'latex-math-preview-move-to-downward-item)
      (define-key map (kbd "p") 'latex-math-preview-move-to-upward-item)
      (define-key map (kbd "C-n") 'latex-math-preview-move-to-downward-item)
      (define-key map (kbd "C-p") 'latex-math-preview-move-to-upward-item)
      (define-key map (kbd "f") 'latex-math-preview-move-to-right-item)
      (define-key map (kbd "b") 'latex-math-preview-move-to-left-item)
      (define-key map (kbd "C-f") 'latex-math-preview-move-to-right-item)
      (define-key map (kbd "C-b") 'latex-math-preview-move-to-left-item)
      (define-key map (kbd "<down>") 'latex-math-preview-move-to-downward-item)
      (define-key map (kbd "<up>") 'latex-math-preview-move-to-upward-item)
      (define-key map (kbd "<right>") 'latex-math-preview-move-to-right-item)
      (define-key map (kbd "<left>") 'latex-math-preview-move-to-left-item)
      (define-key map (kbd "C-v") 'latex-math-preview-scroll-up)
      (define-key map (kbd "M-v") 'latex-math-preview-scroll-down)
      (define-key map (kbd "SPC") 'latex-math-preview-scroll-up)
      (define-key map (kbd "S-SPC") 'latex-math-preview-scroll-down)
      (define-key map (kbd "s") 'latex-math-preview-insert-isearch-forward)
      (define-key map (kbd "C-s") 'latex-math-preview-insert-isearch-forward)
      (define-key map (kbd "r") 'latex-math-preview-insert-isearch-backward)
      (define-key map (kbd "C-r") 'latex-math-preview-insert-isearch-backward)
      (define-key map (kbd "i") 'latex-math-preview-next-candidates-for-insertion)
      (define-key map (kbd "u") 'latex-math-preview-previous-candidates-for-insertion)
      (define-key map (kbd "C-d") 'latex-math-preview-delete-current-cache)
      (define-key map (kbd "C-m") 'latex-math-preview-put-selected-candidate)
      (define-key map (kbd "M-<") 'latex-math-preview-move-to-beginning-of-candidates)
      (define-key map (kbd "M->") 'latex-math-preview-move-to-end-of-candidates)
      (define-key map (kbd "<return>") 'latex-math-preview-put-selected-candidate)
      (define-key map (kbd "<mouse-1>") 'latex-math-preview-put-candidate-mouse-selecting)
      (setq latex-math-preview-insert-symbol-map map)))

;;-----------------------------------------------------------------------------
;; Convert image

(defvar latex-math-preview-working-directory nil
  "Working directory. This variable must not be set.")

(defvar latex-math-preview-command-buffer "*latex-math-preview-command*"
  "Buffer name of command process.")

(defvar latex-math-preview-trim-image nil
  "If this variable is t, trim margin when creating images.
This variable must not be set.")

(defvar latex-math-preview-gs-resolution 100
  "Resolution for `latex-math-preview-execute-gs-to-png'.")

(defvar latex-math-preview-command-path-alist nil
  "List of pair of command and path.")

(defvar latex-math-preview-command-option-alist
  '((pdflatex-to-pdf "-output-format" "pdf") (pdflatex-to-dvi "-output-format" "dvi")
    (lualatex-to-pdf "-output-format" "pdf") (lualatex-to-dvi "-output-format" "dvi")
    (dvipng "-x" "1728") (dvips-to-ps "-Ppdf") (dvips-to-eps "-Ppdf")
    (gs-to-png
     "-dSAFER" "-dNOPAUSE" "-sDEVICE=png16m" "-dTextAlphaBits=4" "-dBATCH" "-dGraphicsAlphaBits=4" "-dQUIET")
    (gswin32c-to-png
     "-dSAFER" "-dNOPAUSE" "-sDEVICE=png16m" "-dTextAlphaBits=4" "-dBATCH" "-dGraphicsAlphaBits=4" "-dQUIET"))
  "Options of commands.")

(defvar latex-math-preview-command-trim-option-alist
  '((dvipng "-T" "tight") (dvips-to-ps "-E" "-x" "3000") (dvips-to-eps "-E" "-x" "3000") (convert "-trim"))
  "Options of commands to trim margin.")

(eval-and-compile
  (defvar latex-math-preview-command-output-extension-alist
    '((latex . "dvi") (platex . "dvi") (dvipng . "png") (dvipdf . "pdf") (dvipdfm . "pdf") (dvipdfmx . "pdf"))
    "List of command and extension of output file."))

(defvar latex-math-preview-tex-to-png-for-preview
  '(latex dvipng)
  "Sequence of end of function names to create png image for preview.
This variable is buffer local.")

(defvar latex-math-preview-tex-to-png-for-save
  '(latex dvipng)
  "Sequence of end of function names to create png image for save.
This variable is buffer local.")

(defvar latex-math-preview-tex-to-eps-for-save
  '(latex dvips-to-eps)
  "Sequence of end of function names to create eps image for save.
This variable is buffer local.")

(defvar latex-math-preview-tex-to-ps-for-save
  '(latex dvips-to-ps)
  "Sequence of end of function names to create ps image for save.
This variable is buffer local.")

(defvar latex-math-preview-beamer-to-png
  '(pdflatex-to-pdf gs-to-png)
  "Sequence of end of function names to create png image for previewing beamer page.
This variable is buffer local.")

(defvar latex-math-preview-conversion-variables
  '(latex-math-preview-tex-to-png-for-preview
    latex-math-preview-tex-to-png-for-save
    latex-math-preview-tex-to-eps-for-save
    latex-math-preview-tex-to-ps-for-save
    latex-math-preview-beamer-to-png))

(dolist (var latex-math-preview-conversion-variables)
  (make-variable-buffer-local var))

(defun latex-math-preview-get-command-path (command-key)
  (or (cdr (assoc command-key latex-math-preview-command-path-alist)) (symbol-name command-key)))

(defun latex-math-preview-get-command-option (key)
  (let ((args (cdr (assoc key latex-math-preview-command-option-alist))))
    (if latex-math-preview-trim-image
	(append args (cdr (assoc key latex-math-preview-command-trim-option-alist))) args)))

(defun latex-math-preview-call-command-process (command args)
  (= 0 (apply 'call-process command nil latex-math-preview-command-buffer nil args)))

(defun latex-math-preview-latex-command-execute (command input opts extension)
  (let ((dir (or latex-math-preview-working-directory (file-name-directory input) ".")))
    (if (latex-math-preview-call-command-process command `(,@opts ,(concat "-output-directory=" dir) ,input))
	(concat dir "/" (file-name-sans-extension (file-name-nondirectory input)) "." extension)
      nil)))

(eval-and-compile
  (defun latex-math-preview-get-command-output-extension (key)
    (or (cdr (assoc key latex-math-preview-command-output-extension-alist))
	(let ((name (symbol-name key))) (if (string-match "-to-\\(.*\\)$" name) (match-string 1 name) nil))))

  (defmacro latex-math-preview-define-latex-function (command)
    `(defun ,(intern (concat "latex-math-preview-execute-" (symbol-name command))) (input)
       (latex-math-preview-latex-command-execute
	(latex-math-preview-get-command-path (quote ,(intern (car (split-string (symbol-name command) "-"))))) input
	(latex-math-preview-get-command-option (quote ,command))
	,(latex-math-preview-get-command-output-extension command)))))

(latex-math-preview-define-latex-function latex)
(latex-math-preview-define-latex-function platex)
(latex-math-preview-define-latex-function pdflatex-to-dvi)
(latex-math-preview-define-latex-function pdflatex-to-pdf)
(latex-math-preview-define-latex-function lualatex-to-dvi)
(latex-math-preview-define-latex-function lualatex-to-pdf)

(defvar latex-math-preview-convert-dvipng-color-mode nil)

(defun latex-math-preview-read-image-color-argument (prompt default-val)
  (catch :get
    (while t
      (let ((val (read-from-minibuffer
		  (concat prompt " [RGB] (default " (mapconcat 'identity default-val " ") "): "))))
	(setq val (if (= (length val) 0) default-val (split-string val " ")))
	(catch :invalid-color
	  (when (= (length val) 3)
	    (dolist (s val)
	      (let ((num (string-to-number s))) (when (or (< num 0.0) (> num 1.0)) (throw :invalid-color t))))
	    (throw :get val)))
	(message "Invalid color.")
	(sleep-for 1)))))

(defun latex-math-preview-argument-dvipng (command input)
  (let* ((output (concat (file-name-sans-extension input) "."
			 (latex-math-preview-get-command-output-extension command)))
	 (args (append (latex-math-preview-get-command-option command)
		       (list "-o" output input))))
    (cond
     ((eq 'read latex-math-preview-convert-dvipng-color-mode)
      (setq args
	    (append args (list "-bg" (concat "rgb " (mapconcat 'identity
							       (latex-math-preview-read-image-color-argument
								"Background" '("1.0" "1.0" "1.0")) " "))
			       "-fg" (concat "rgb " (mapconcat 'identity
							       (latex-math-preview-read-image-color-argument
								"Foreground" '("0.0" "0.0" "0.0")) " "))))))
     ((eq 'buffer latex-math-preview-convert-dvipng-color-mode)
      (setq args
	    (append args
		    (or latex-math-preview-dvipng-color-option
			(setq latex-math-preview-dvipng-color-option
			      (latex-math-preview-get-dvipng-color-option)))))))
    (cons output args)))

(defun latex-math-preview-change-file-extension (command input)
  (concat (file-name-sans-extension input) "." (latex-math-preview-get-command-output-extension command)))

(defun latex-math-preview-argument-convert-dvi (command input)
  (let* ((out (latex-math-preview-change-file-extension command input))
	 (args (append (latex-math-preview-get-command-option command) (list "-o" out input))))
    (cons out args)))

(defun latex-math-preview-argument-dvipdf (command input)
  (let* ((out (latex-math-preview-change-file-extension command input))
	 (args (append (latex-math-preview-get-command-option command) (list input out))))
    (cons out args)))

(defun latex-math-preview-argument-gs-to-png (command input)
  (let* ((out (latex-math-preview-change-file-extension command input))
	 (args (append (latex-math-preview-get-command-option command)
		       (list (concat "-r" (number-to-string latex-math-preview-gs-resolution))
			     (concat "-sOutputFile=" out) input))))
    (cons out args)))

(defvar latex-math-preview-command-create-argument-alist
  '((dvipng . latex-math-preview-argument-dvipng)
    (dvips-to-ps . latex-math-preview-argument-convert-dvi)
    (dvips-to-eps . latex-math-preview-argument-convert-dvi)
    (dvipdf . latex-math-preview-argument-dvipdf)
    (dvipdfm . latex-math-preview-argument-convert-dvi)
    (dvipdfmx . latex-math-preview-argument-convert-dvi)
    (gs-to-png . latex-math-preview-argument-gs-to-png)
    (gswin32c-to-png . latex-math-preview-argument-gs-to-png))
  "List of command and function name to create arguments.")

(defun latex-math-preview-get-command-argument (command input)
  (let ((func (cdr (assoc command latex-math-preview-command-create-argument-alist))))
    (if func (funcall func command input) nil)))

(defun latex-math-preview-call-latex-command (command-path command input)
  (let ((tmp (latex-math-preview-get-command-argument command input)))
    (if (latex-math-preview-call-command-process command-path (cdr tmp)) (car tmp) nil)))

(defmacro latex-math-preview-define-convert-function (command)
  "Define function to convert images. Use first element of
a list created by splitting COMMAND by \"-\" as a command name."
  `(defun ,(intern (concat "latex-math-preview-execute-" (symbol-name command))) (input)
     (latex-math-preview-call-latex-command
      (latex-math-preview-get-command-path (quote ,(intern (car (split-string (symbol-name command) "-")))))
      (quote ,command) input)))

(latex-math-preview-define-convert-function dvipng)
(latex-math-preview-define-convert-function dvips-to-ps)
(latex-math-preview-define-convert-function dvips-to-eps)
(latex-math-preview-define-convert-function dvipdf)
(latex-math-preview-define-convert-function dvipdfm)
(latex-math-preview-define-convert-function dvipdfmx)
(latex-math-preview-define-convert-function gs-to-png)
(latex-math-preview-define-convert-function gswin32c-to-png)

(defun latex-math-preview-successive-convert (input &rest convert-list)
  (let ((product input))
    (catch :no-output
      (dolist (conv convert-list)
	(setq product (funcall (intern (concat "latex-math-preview-execute-" (symbol-name conv))) product))
	(unless product (throw :no-output nil))))
    product))

(defun latex-math-preview-completing-read-convert-command-sequence ()
  (let* ((cmd-list
	  (mapcar
	   (lambda (cmd-sym)
	     (replace-regexp-in-string "^latex-math-preview-execute-" "" (symbol-name cmd-sym)))
	   (apropos-internal "latex-math-preview-execute-" 'functionp)))
	 (cmd (completing-read "Conversion: " cmd-list nil t))
	 (cmd-seq))
    (while (> (length cmd) 0)
      (setq cmd-seq (append cmd-seq (list cmd)))
      (setq cmd (completing-read "Conversion: " cmd-list nil t)))
    (mapcar 'intern cmd-seq)))

(defun latex-math-preview-set-conversion-command ()
  "Set sequence of conversion commands for current buffer latex file."
  (interactive)
  (let ((var (completing-read
	      "Set variable: "
	      (mapcar (lambda (sym) (replace-regexp-in-string "^latex-math-preview-" "" (symbol-name sym)))
		      latex-math-preview-conversion-variables) nil t)))
    (set (intern (concat "latex-math-preview-" var))
	 (latex-math-preview-completing-read-convert-command-sequence))))

(defvar latex-math-preview-custom-conversion-to-save-image nil)

(defvar latex-math-preview-convert-command-list nil)

(defun latex-math-preview-reset-custom-convert ()
  (interactive)
  (setq latex-math-preview-convert-command-list nil)
  (setq latex-math-preview-custom-conversion-to-save-image nil))

(defun latex-math-preview-set-custom-convert ()
  (interactive)
  (latex-math-preview-reset-custom-convert)
  (setq latex-math-preview-custom-conversion-to-save-image
	(latex-math-preview-completing-read-convert-command-sequence)))

;; (defun latex-math-preview-convert-imagemagick-trim (input)
;;   (let ((old (make-temp-name input)))
;;     (rename-file input old)
;;     (if (= 0 (apply 'call-process (car latex-math-preview-command-imagemagick-convert) nil
;; 		    latex-math-preview-command-buffer nil (list "-trim" old input)))
;; 	(progn
;; 	  (delete-file old)
;; 	  input)
;;       (rename-file old input)
;;       nil)))

;;-----------------------------------------------------------------------------
;; Search usepackage

(defvar latex-math-preview-usepackage-cache nil
  "List of usepackage. If the value is t we do not set usepackage.
If the value is nil this cache has not been set yet.")
(make-variable-buffer-local 'latex-math-preview-usepackage-cache)

;; [TODO] The name of function `latex-math-preview-search-header-usepackage' is not suitable
;; because for not only usepackage but also definitions of commands.
(defun latex-math-preview-search-header-usepackage ()
  "Return list of \\usepackage which is used in current buffer."
  (save-excursion
    (goto-char (point-min))
    (let ((beg-doc (if (search-forward "\\begin{document}" nil t) (point) (point-max)))
	  cmds)
      (goto-char (point-min))
      (while (re-search-forward "\\(\\\\usepackage[^}]*}\\)\\|\\(\\\\DeclareMathOperator{.*}$\\)\\|\\(\\\\providecommand{.*}$\\)" beg-doc t)
	(let ((tmp-str (match-string-no-properties 0)))
	  (save-excursion
	    (when (not (re-search-backward "\\(^\\|[^\\\\]\\)%" (line-beginning-position) t))
	      (add-to-list 'cmds tmp-str)))))
      (nreverse cmds))))

(defun latex-math-preview-search-header-usepackage-other-file (filename)
  "Return list of \\usepackage in other file."
  (if (and (file-exists-p filename) (not (file-directory-p filename)))
      (with-temp-buffer
	(insert-file-contents filename)
	(goto-char (point-min))
	(latex-math-preview-search-header-usepackage))
    nil))

(defun latex-math-preview-get-header-usepackage ()
  "Return cache of usepackage and create cache data if needed.
If current buffer has no usepackage line and the corresponding file exists
then this function ask you main tex file having usepackage lines.
If current buffer is not a file we are not asked."
  (when (not latex-math-preview-usepackage-cache)
    (let ((cache (latex-math-preview-search-header-usepackage)))
      (when (and (not cache)
		 (let ((filename (buffer-file-name (current-buffer))))
		   (and filename (string-match "\\.tex" filename))))
	(setq cache (latex-math-preview-search-header-usepackage-other-file
		     (read-file-name "Main TeX file: " nil default-directory))))
      (if (listp cache)
	  (progn
	    (setq latex-math-preview-usepackage-cache nil)
	    (dolist (line cache)
	      (let ((filtered-line
		     (catch :match
		       (dolist (filter latex-math-preview-usepackage-filter-alist)
			 (when (string-match-p (car filter) line)
			   (let ((func (cdr filter)))
			     (throw :match (if func (funcall func line) nil)))))
		       line)))
		(when filtered-line
		  (setq latex-math-preview-usepackage-cache
			(append latex-math-preview-usepackage-cache (list filtered-line)))))))
	(setq latex-math-preview-usepackage-cache t))))
  (if (listp latex-math-preview-usepackage-cache) latex-math-preview-usepackage-cache nil))

(defvar latex-math-preview-edit-usepackage-buffer "*latex-math-preview: usepackage cache*")
(defvar latex-math-preview-edit-usepackage-parent-buffer nil)
(defvar latex-math-preview-edit-usepackage-map nil
  "Keymap for editing usepackage of latex-math-preview-insert-symbol.")
(defvar latex-math-preview-usepackage-filter-alist nil
  "List of filter for lines of usepackage.
The value is a list of (REGEXP . nil) or (REGEXP . (lambda (line) ... )).
If you want to ignore some usepackages, then you add filters to this variable.
For example, to ignore \\usepackage{txfonts}, we add '(\"txfonts\") to this list.
If color-related packages can produce unexpected colors in the
generated images, we can add '(\"color\").")

(or latex-math-preview-edit-usepackage-map
    (let ((map (make-sparse-keymap)))
      (define-key map "\C-c\C-c" 'latex-math-preview-edit-usepackage-finish)
      (setq latex-math-preview-edit-usepackage-map map)))

(defun latex-math-preview-edit-usepackage ()
  "Edit header of usepackages, which are used in LaTeX files to create previews.
Press C-c C-c to finish editing."
  (interactive)
  (if latex-math-preview-usepackage-cache
      (let ((parent-buffer (buffer-name (current-buffer)))
	    (tmp-buffer (get-buffer-create latex-math-preview-edit-usepackage-buffer))
	    (usepackages latex-math-preview-usepackage-cache))
	(with-current-buffer tmp-buffer
	  (insert "% C-c C-c : Finish editing\n\n")
	  (dolist (line usepackages)
	    (insert line "\n")))
	(pop-to-buffer tmp-buffer)
	(goto-char (point-min))
	(forward-line 2)
	(make-variable-buffer-local 'latex-math-preview-edit-usepackage-parent-buffer)
	(setq latex-math-preview-edit-usepackage-parent-buffer parent-buffer)
	(use-local-map latex-math-preview-edit-usepackage-map))
    (message "No usepackage cache.")))

(defun latex-math-preview-edit-usepackage-finish ()
  "Finish editing usepackages."
  (interactive)
  (when latex-math-preview-edit-usepackage-parent-buffer
    (let ((buffer-to-kill (current-buffer))
	  (packages (latex-math-preview-search-header-usepackage)))
      (with-current-buffer latex-math-preview-edit-usepackage-parent-buffer
	(setq latex-math-preview-usepackage-cache packages))
      (pop-to-buffer latex-math-preview-edit-usepackage-parent-buffer)
      (kill-buffer buffer-to-kill))))

(defun latex-math-preview-reload-usepackage (&optional other-file)
  "Reload usepackage cache from current buffer. If you want to get the cache
from other file, you use C-u M-x `latex-math-preview-reload-usepackage'."
  (interactive "P")
  (setq latex-math-preview-usepackage-cache nil)
  (setq latex-math-preview-usepackage-cache
	(if other-file
	    (or (latex-math-preview-search-header-usepackage-other-file
		 (read-file-name "Main TeX file: " nil default-directory)) t)
	  (latex-math-preview-get-header-usepackage))))

(defun latex-math-preview-bounds-of-latex-math ()
  "A `bounds-of-thing-at-point' function for a LaTeX mathematical expression.
See `latex-math-preview-match-expression' for what's matched.
The return is a pair of buffer positions (START . END), or nil if
no recognised expression at or surrounding point."

  ;; TeX style $...$ could easily match some huge chunk of the buffer, and
  ;; even @math{...} or <math>...</math> could occur in comments or some
  ;; unrelated context.  So it's not reliable just to take the first of
  ;; these which match, instead the strategy is to check for all forms
  ;; around point and take the one that's the smallest.
  ;;
  ;; Only the start position of the match is considered for "smallest", the
  ;; one that's the shortest distance before point (but covering point of
  ;; course) in the buffer is taken.

  (let (case-fold-search beg end)

    ;; $...$ and $$...$$
    ;; thing-at-point-looking-at doesn't work on "$...$".  The way the start
    ;; and end are the same (ie. "$") breaks the straightforward
    ;; implementation of that function; so the idea here is to search back
    ;; for the starting "$", and one not "\$" escaped, then check the $...$
    ;; extent covers point
    (save-excursion
      (while (and (search-backward "$" nil t) ;; $ not preceded by \
                  (eq ?\\ (char-before))))
      (skip-chars-backward "$")
      (when (or (looking-at "\\(\\$\\$\\(?:\\\\\\$\\|[^$]\\)+?\\$\\$\\)")
		(looking-at "\\(\\$\\(?:\\\\\\$\\|[^$]\\)+?\\$\\)"))
        (setq beg (match-beginning 1) end (match-end 1))))

    (dolist (elem latex-math-preview-match-expression)
      (when (thing-at-point-looking-at (cdr elem))
        ;; if no other match, or this match is later, then override
        (if (or (not beg)
                (> (match-beginning (car elem)) beg))
            (setq beg (match-beginning (car elem)) end (match-end (car elem))))))

    (and beg
         (cons beg end))))

(put 'latex-math 'bounds-of-thing-at-point 'latex-math-preview-bounds-of-latex-math)

(defun latex-math-preview-in-math-mode-p ()
  "Return non-nil if current position is in mathematical expression.
This function may make mistake when there is sequence of '$'.
If you use YaTeX, then you should use YaTeX-in-math-mode-p alternatively."
  (thing-at-point 'latex-math))

(defun latex-math-preview-clear-working-directory ()
  (when (and latex-math-preview-working-directory (not latex-math-preview-not-delete-tmpfile))
    (latex-math-preview-clear-tmp-directory latex-math-preview-working-directory))
  (setq latex-math-preview-working-directory nil))

(defun latex-math-preview-create-temporary-tex-filename ()
  (setq latex-math-preview-working-directory (make-temp-file "latex-math-preview-" t))
  (concat latex-math-preview-working-directory "/" latex-math-preview-temporary-file-prefix ".tex"))

(defun latex-math-preview-make-temporary-tex-file (math-exp template-header &optional usepackages)
  (let ((dot-tex (latex-math-preview-create-temporary-tex-filename))
	(usepck (or usepackages (latex-math-preview-get-header-usepackage)
		    latex-math-preview-latex-usepackage-for-not-tex-file))
	(coding-system buffer-file-coding-system))
    (with-temp-file dot-tex
      (insert template-header
	      (if usepck (mapconcat 'identity usepck "\n") "")
	      "\n\\begin{document}\n" math-exp "\n\\par\n\\end{document}\n")
      (set-buffer-file-coding-system coding-system))
    dot-tex))

(defun latex-math-preview-raise-can-not-create-image (dot-tex)
  (with-current-buffer (get-buffer-create latex-math-preview-command-buffer)
    (goto-char (point-min))
    (while (not (eobp))
      (insert "% ")
      (forward-line 1))
    (goto-char (point-min))
    (insert "% " (make-string 5 ?-) " Created by latex-math-preview.el at "
	    (format-time-string "%Y/%m/%d %H:%M:%S") " " (make-string 5 ?-) "\n% \n% If \\usepackage lines raise errors \n% then we should edit them by M-x latex-math-preview-edit-usepackage\n% \n% If you want to exclude some \\usepackage lines anytime\n% then you should configure the variable latex-math-preview-usepackage-filter-alist\n% \n")
    (save-excursion
      (insert "\n\n% " (make-string 5 ?-) " Error message " (make-string 5 ?-) "\n"))
    (insert-file-contents dot-tex)
    (goto-char (point-min)))
  (pop-to-buffer latex-math-preview-command-buffer)
  (funcall latex-math-preview-error-buffer-major-mode)
  (rename-buffer (generate-new-buffer-name latex-math-preview-tex-processing-error-buffer-name))
  (signal 'tex-processing-error '("TeX processing error")))

(defun latex-math-preview-make-png-file (dot-tex)
  "Make png image from DOT-TEX."
  (let ((latex-math-preview-convert-dvipng-color-mode 'buffer)
	(latex-math-preview-trim-image t))
    (or (apply 'latex-math-preview-successive-convert dot-tex latex-math-preview-tex-to-png-for-preview)
	(latex-math-preview-raise-can-not-create-image dot-tex))))

(defun latex-math-preview-clear-tmp-directory (dir)
  "Delete temporary directory and files contained in it."
  (when (file-directory-p dir)
    (progn
      (let ((directories))
	(dolist (file (directory-files dir))
	  (let ((path (concat dir "/" file)))
	    (cond ((and (file-directory-p path) (not (string-match "^\\.+$" file)))
		   (add-to-list 'directories file))
		  ((file-regular-p path)
		   (condition-case nil (delete-file path)
		     (message "Can not delete '%s'" path))))))
	(dolist (del-dir directories)
	  (message del-dir)
	  (latex-math-preview-clear-tmp-directory (concat dir "/" del-dir))))
      (condition-case nil (delete-directory dir)
	(message "Can not delete '%s'" dir)))))

;;-----------------------------------------------------------------------------
;; view png in a buffer

(defvar latex-math-preview-display-whole-image
  "Change preview window to full size when whole image is not displayed if true"
  nil)

(defun latex-math-preview-get-expression-buffer ()
  (or (get-buffer latex-math-preview-expression-buffer-name)
      (let ((buf (get-buffer-create latex-math-preview-expression-buffer-name)))
	(with-current-buffer buf
	  (latex-math-preview-expression-mode)
	  (buffer-disable-undo))
	buf)))

(defun latex-math-preview-png-image (image &optional win-conf)
  "Display png image IMAGE in a buffer."
  (or (and (image-type-available-p 'png) (display-images-p)) (error "Cannot display PNG in this Emacs"))
  (with-current-buffer (latex-math-preview-get-expression-buffer)
    (when win-conf (setq latex-math-preview-previous-window-configuration win-conf))
    (setq cursor-type nil)
    (let ((inhibit-read-only t))
      (setq buffer-read-only nil)
      (erase-buffer)
      (insert "\n ")
      (insert-image-file image)
      (goto-char (point-min))
      (setq buffer-read-only t)))
  (if latex-math-preview-select-preview-window
      (pop-to-buffer latex-math-preview-expression-buffer-name)
    (display-buffer latex-math-preview-expression-buffer-name))
  (with-selected-window (get-buffer-window latex-math-preview-expression-buffer-name)
    (when (and latex-math-preview-display-whole-image (not (pos-visible-in-window-p (point-max))))
      (with-current-buffer latex-math-preview-expression-buffer-name (delete-other-windows)))))

(defun latex-math-preview-get-dvipng-color-option ()
  "Get string for dvipng options '-bg' and '-fg'."
  (let ((max (car (color-values "#ffffff"))))
    (list "-bg"
	  (concat "rgb "
		  (mapconcat
		   (lambda (col)
		     (let ((val (/ (float col) max)))
		       (cond ((> val 1.0) (setq val 1.0))
			     ((< val 0.0) (setq val 0.0)))
		       (format "%.02f" val)))
		   (color-values (or latex-math-preview-image-background-color
				     (face-background 'default))) " "))
	  "-fg"
	  (concat "rgb "
		  (mapconcat
		   (lambda (col)
		     (let ((val (/ (float col) max)))
		       (cond ((> val 1.0) (setq val 1.0))
			     ((< val 0.0) (setq val 0.0)))
		       (format "%.02f" val)))
		   (color-values (or latex-math-preview-image-foreground-color
				     (face-foreground 'default))) " ")))))

(defun latex-math-preview-convert-to-output-file (func args output)
  (let ((out (apply func args)))
    (if (and out output (not (file-exists-p output)))
	(progn
	  (rename-file out output)
	  output)
      out)))

(defun latex-math-preview-cut-mathematical-expression (&optional remove-num-expression)
  (let ((str))
    (if (and transient-mark-mode mark-active)
	(progn
	  (setq str (buffer-substring (region-beginning) (region-end)))
	  (setq mark-active nil))
      ;; If you use (region-active-p), then the program can not work on emacs 22.
      (setq str (thing-at-point 'latex-math)))
    (if (and str remove-num-expression)
	(dolist (env remove-num-expression)
	  (setq str (replace-regexp-in-string (format "{%s}" env) (format "{%s\*}" env) str))))
    str))

;;;###autoload
(defun latex-math-preview-expression ()
  "Preview a TeX maths expression at (or surrounding) point.
The `latex-math-preview-function' variable controls the viewing method.
The LaTeX notations which can be matched are $...$, $$...$$ or
the notations which are stored in `latex-math-preview-match-expression'."
  (interactive)
  (let ((str (latex-math-preview-cut-mathematical-expression)))
    (if str
	(let ((dot-tex (latex-math-preview-make-temporary-tex-file str latex-math-preview-latex-template-header)))
	  (latex-math-preview-png-image (latex-math-preview-make-png-file dot-tex) (current-window-configuration))
	  (latex-math-preview-clear-working-directory))
      (message "Not in a TeX mathematical expression."))))

(defun latex-math-preview-make-image-for-save (func-sequence output dot-tex)
  "Create an image from DOT-TEX by FUNC-SEQUENCE and save as OUTPUT."
  (let ((latex-math-preview-convert-dvipng-color-mode 'read)
	(latex-math-preview-trim-image t))
    (or (latex-math-preview-convert-to-output-file
	 'latex-math-preview-successive-convert (cons dot-tex func-sequence) output)
	(latex-math-preview-raise-can-not-create-image dot-tex))))

(defun latex-math-preview-prompt-for-save-image-file (use-custom-conversion)
  (if use-custom-conversion
      (let ((extension (latex-math-preview-get-command-output-extension
			(nth (1- (length latex-math-preview-custom-conversion-to-save-image))
			     latex-math-preview-custom-conversion-to-save-image))))
	(concat "Save as" (if extension (concat " (*." extension ")") "")": "))
    "Save as (*.png, *.eps, or *.ps): "))

;;;###autoload
(defun latex-math-preview-save-image-file (use-custom-conversion &optional output)
  (interactive "P")
  (let ((prompt (latex-math-preview-prompt-for-save-image-file use-custom-conversion)))
    (if (not output) (setq output (read-file-name prompt nil default-directory)))
    (while (file-directory-p (expand-file-name output))
      (message "Please specify filename not directory.")
      (sleep-for 1)
      (setq output (read-file-name prompt nil default-directory))))
  (if (or (not (file-exists-p output)) (y-or-n-p "File exists. Overwrite? "))
      (let ((str (latex-math-preview-cut-mathematical-expression
		  latex-math-preview-match-expression-remove-formula-number)))
	(if str
	    (let ((func-series
		   (cond
		    (use-custom-conversion latex-math-preview-custom-conversion-to-save-image)
		    ((string-match "\\.png$" output) latex-math-preview-tex-to-png-for-save)
		    ((string-match "\\.eps$" output) latex-math-preview-tex-to-eps-for-save)
		    ((string-match "\\.ps$" output) latex-math-preview-tex-to-ps-for-save)
		    (t nil)))
		  (dot-tex (latex-math-preview-make-temporary-tex-file
			    str latex-math-preview-template-header-for-save-image)))
	      (if (not func-series) (message "Can not specify conversion.")
		(if (latex-math-preview-make-image-for-save func-series output dot-tex)
		    (message "Save image as %s" output) (message "Can not create an image file.")))
	      (latex-math-preview-clear-working-directory))
	  (message "Not in a TeX mathematical expression.")))
    (message "Stop making image.")))

;;-----------------------------------------------------------------------------
;; Manage window

(defun latex-math-preview-quit-window ()
  "Quit preview window."
  (interactive)
  (when latex-math-preview-previous-window-configuration
    (set-window-configuration latex-math-preview-previous-window-configuration)
    (setq latex-math-preview-previous-window-configuration nil)))

(defun latex-math-preview-delete-buffer ()
  "Delete buffer which is created for preview."
  (interactive)
  (if latex-math-preview-select-preview-window
      (let ((buf (current-buffer)))
        (latex-math-preview-quit-window)
        (kill-buffer buf))
    (let ((buf (get-buffer latex-math-preview-expression-buffer-name))
          (win (get-buffer-window latex-math-preview-expression-buffer-name)))
      (when buf
        (when win
          (with-selected-window win
            (latex-math-preview-quit-window)))
        (kill-buffer buf)))))

;;-----------------------------------------------------------------------------
;; Insert Mathematical expression

(defvar latex-math-preview-insert-symbol-column-size nil)
(make-variable-buffer-local 'latex-math-preview-insert-symbol-column-size)

(defun latex-math-preview-cache-directory (key)
  (concat latex-math-preview-cache-directory-for-insertion "/" key))

(defun latex-math-preview-clear-cache-for-insertion (&optional key)
  "Delete cache images in directory of which name is KEY.
If KEY is nil then all directories saving caches is deleted."
  (interactive)
  (if key
      (dolist (name-and-sets latex-math-preview-list-name-symbol-datasets)
	(when (assoc key (symbol-value (cdr name-and-sets)))
	  (latex-math-preview-clear-tmp-directory (latex-math-preview-cache-directory key))
	  (message "Finish deleting image caches of \"%s\"" key)))
    (latex-math-preview-clear-tmp-directory latex-math-preview-cache-directory-for-insertion)
    (message "Finish deleting all image caches.")))

(defun latex-math-preview-make-symbol-candidate-image (latex-symbol packages)
  "Create a cache image from latex file including LATEX-SYMBOL."
  (let* ((latex-math-preview-convert-dvipng-color-mode 'buffer)
	 (latex-math-preview-trim-image t)
	 (dot-tex (latex-math-preview-symbol-tex-source latex-symbol packages))
	 (png (latex-math-preview-convert-to-output-file
	       'latex-math-preview-successive-convert (cons dot-tex latex-math-preview-tex-to-png-for-preview)
	       (latex-math-preview-symbol-image latex-symbol))))
    (unless png (latex-math-preview-raise-can-not-create-image dot-tex))
    (latex-math-preview-clear-working-directory)
    png))

(defun latex-math-preview-make-symbol-caches (key dataset type)
  "Create cache images which are associated with KEY in directory of which name is KEY.
TYPE is 'math or 'text."
  (when (listp dataset)
    (let ((dirpath (latex-math-preview-cache-directory key)))
      (if (file-directory-p dirpath)
	  (message "'%s' exists. Cache may be used." dirpath)
	(make-directory dirpath t)
	(message "Creating images. Please wait for a while.")
	(dolist (subcat dataset)
	  (let ((desc (car subcat))
		(packages (cadr subcat))
		(sym-set (nth 2 subcat)))
	    (dolist (sym sym-set)
	      (latex-math-preview-make-symbol-candidate-image
	       (latex-math-preview-symbol-make
		sym dirpath (eq type 'math)) packages))))
	(message "Finish making cache images of \"%s\"." key)))))

(defun latex-math-preview-make-all-cache-images ()
  "Create all cache images."
  (interactive)
  (dolist (name-and-sets latex-math-preview-list-name-symbol-datasets)
    (let ((symbol-datasets (symbol-value (cdr name-and-sets)))
	  (type (car name-and-sets)))
      (dolist (dataset symbol-datasets)
	(latex-math-preview-make-symbol-caches (car dataset) (cdr dataset) type))))
  (message "Finish making all cache images."))

(defun latex-math-preview-strings-and-images-sizes (sym-list)
  "Look over cache images.
Return maximum size of images and maximum length of strings and images"
  (let ((max-img-size 0) (max-str-length 0))
    (dolist (sym sym-list)
      (let* ((img (create-image (latex-math-preview-symbol-image sym) 'png nil :ascent 'center))
	     (size (car (image-size img t)))
	     (str-len (length (latex-math-preview-symbol-string sym))))
	(when (< max-img-size size) (setq max-img-size size))
	(when (< max-str-length str-len) (setq max-str-length str-len))))
    (list max-img-size max-str-length)))

(defun latex-math-preview-insert-key-explanations ()
  "Insert explanations of key map."
  (insert "key:")
  (add-text-properties (point-min) (point) '(face bold))
  (let ((max (window-width)))
    (dolist (text '("[RET] insert" "[j] down" "[k] up" "[h] left" "[l] right"
		    "[i] next page" "[u] previous page" "[o] change window size"
		    "[c] change page" "[q] quit"))
      (if (> (+ (current-column) (length text)) max)
	  (insert "\n    "))
      (insert "   " text)))
  (insert "\n")
  (save-excursion
    (goto-char (point-min))
    (while (re-search-forward "\\[" nil t)
      (backward-char)
      (let ((start-pt (point)))
	(if (re-search-forward "\\]" nil t)
	    (add-text-properties start-pt (point)
				 '(face latex-math-preview-key-for-insertion-face)))))))

(defun latex-math-preview-insert-subcategory-infomation (subcat-str packages)
  "Insert information of images associated with SUBCAT-STR."
  (let* ((desc (concat (make-string 5 ?-) " * " subcat-str " * "))
	 (package-str)
	 (num-dash (- (window-width) (length desc)))
	 (start-pt (point)))
    (insert desc)
    (add-text-properties start-pt (point) '(face bold))
    (setq start-pt (point))
    (if packages
	(progn
	  (setq package-str (concat (mapconcat 'identity packages " ") " "))
	  (insert package-str)
	  (setq num-dash (- num-dash (length package-str)))
	  (add-text-properties start-pt (point)
			       '(face latex-math-preview-key-for-insertion-face))))
    (insert (make-string num-dash ?-)))
  (insert "\n"))

(defun latex-math-preview-insert-candidate-images (key dataset)
  "Insert images and expressions."
  (setq latex-math-preview-information-line-number nil)
  (let* ((dirpath (latex-math-preview-cache-directory key))
	 (symset (mapcar (lambda (subcat)
			   (mapcar (lambda (obj)
				     (latex-math-preview-symbol-make
				      obj dirpath (eq latex-math-preview-current-insert-mode 'math)))
				   (nth 2 subcat))) dataset))
	 (imgdata (latex-math-preview-strings-and-images-sizes (apply 'append symset)))
	 (new-tab-width (+ 4 (ceiling (/ (float (car imgdata)) (float (frame-char-width))))))
	 (str-size (* new-tab-width (ceiling (/ (float (+ 6 (car (cdr imgdata)))) (float new-tab-width)))))
	 ;; You must not remove (+ 6 ...).
	 ;; Implementation of latex-math-preview-set-overlay-for-selected-item needs redundant space.
	 (str-format (format "%%-%ds" str-size))
	 (col (floor (/ (window-width)
			(+ str-size (* (ceiling (/ (float (car imgdata))
						   (float (* (frame-char-width) new-tab-width))))
				       new-tab-width)))))
	 (subcat-num 0)
	 (current-col 0)
	 (current-line 1))
    (setq tab-width new-tab-width)
    (setq latex-math-preview-insert-symbol-column-size col)
    (dolist (subcat dataset)
      (latex-math-preview-insert-subcategory-infomation (car subcat) (cadr subcat))
      (dolist (sym (nth subcat-num symset))
	(setq current-col (1+ current-col))
	(latex-math-preview-symbol-insert-candidate sym str-format current-col current-line)
	(when (>= current-col col)
	  (setq current-col 0)
	  (insert "\n")
	  (setq current-line (1+ current-line))))
      (when (> current-col 0)
	(insert "\n")
	(setq current-line (1+ current-line))
	(setq current-col 0))
      (setq subcat-num (1+ subcat-num)))))

(defun latex-math-preview-get-insertion-buffer ()
  (or (get-buffer latex-math-preview-insert-symbol-buffer-name)
      (let ((buf (get-buffer-create latex-math-preview-insert-symbol-buffer-name)))
	(with-current-buffer buf
	  (setq cursor-type nil)
	  (setq truncate-lines t)
	  (setq line-spacing 8)
	  (buffer-disable-undo)
	  (use-local-map latex-math-preview-insert-symbol-map)
	  (setq mode-name "LaTeXPreview"))
	buf)))

(defun latex-math-preview-insertion-get-current-page-key ()
  (or (cdr (assq latex-math-preview-current-insert-mode
		 latex-math-preview-current-page-of-symbol-list))
      (car (car (latex-math-preview-insertion-current-symbol-datasets)))))

(defun latex-math-preview-insertion-set-current-page-key (key)
  (setcdr (assq latex-math-preview-current-insert-mode
		latex-math-preview-current-page-of-symbol-list) key))

(defun latex-math-preview-insertion-current-symbol-datasets ()
  (symbol-value (cdr (assq latex-math-preview-current-insert-mode
			   latex-math-preview-list-name-symbol-datasets))))

(defun latex-math-preview-insertion-current-page-data (key)
  "Get symbol data specified by key. If the associated value is a symbol of a function
then call the function. If the associated value is a symbol of a list then return evaluated value of the list.
If the associated value is a list then return it. Otherwise, raise an error."
  (let ((val (cdr (assoc key (latex-math-preview-insertion-current-symbol-datasets)))))
    (cond
     ((functionp val) (funcall val))
     ((and (symbolp val) (boundp val)) (eval val))
     ((listp val) val)
     (t (error "Invalid data set of symbol insertion")))))

(defun latex-math-preview-symbol-dataset-item-exist-p (dataset)
  (catch :has-item
    (dolist (subcat dataset)
      (when (> (length (nth 2 subcat)) 0)
	(throw :has-item t)))
    nil))

(defun latex-math-preview-create-buffer-for-insertion (key &optional next-page)
  "Create buffer displaying cache images in KEY."
  (unless (and (image-type-available-p 'png) (display-images-p))
    (error "Cannot display PNG in this Emacs"))
  (latex-math-preview-insertion-set-current-page-key key)
  (let ((dataset (latex-math-preview-insertion-current-page-data key))
	(win-conf (current-window-configuration))
	buf)
    (if (latex-math-preview-symbol-dataset-item-exist-p dataset)
	(progn
	  (latex-math-preview-make-symbol-caches key dataset latex-math-preview-current-insert-mode)
	  (setq buf (latex-math-preview-get-insertion-buffer))
	  (pop-to-buffer buf)
	  (setq latex-math-preview-previous-window-configuration win-conf)
	  (if latex-math-preview-always-maximize-window (delete-other-windows))
	  (with-current-buffer buf
	    (setq buffer-read-only nil)
	    (erase-buffer)
	    (latex-math-preview-insert-key-explanations)
	    (latex-math-preview-insert-candidate-images key dataset)
	    (goto-char (point-min))
	    (latex-math-preview-move-to-right-item)
	    (setq buffer-read-only t)))
      (latex-math-preview-next-candidates-for-insertion (or next-page 1)))))

(defun latex-math-preview-insert-symbol-read-page-number ()
  (completing-read "page: " (latex-math-preview-insertion-current-symbol-datasets) nil t))

(defun latex-math-preview-insert-symbol-base (num)
  (let ((key (if (or (not num) (= num 1))
		 (latex-math-preview-insertion-get-current-page-key)
	       (latex-math-preview-insert-symbol-read-page-number))))
    (latex-math-preview-create-buffer-for-insertion key)))

;;;###autoload
(defun latex-math-preview-insert-mathematical-symbol (&optional num)
  "Insert LaTeX mathematical symbols with displaying."
  (interactive "p")
  (setq latex-math-preview-current-insert-mode 'math)
  (latex-math-preview-insert-symbol-base num))

;;;###autoload
(defun latex-math-preview-insert-text-symbol (&optional num)
  "Insert symbols for text part with displaying."
  (interactive "p")
  (setq latex-math-preview-current-insert-mode 'text)
  (latex-math-preview-insert-symbol-base num))

(defun latex-math-preview-set-current-insert-mode ()
  (setq latex-math-preview-current-insert-mode
	(if (funcall latex-math-preview-in-math-mode-p-func) 'math 'text)))

;;;###autoload
(defun latex-math-preview-insert-symbol (&optional num)
  "Insert LaTeX mathematical symbols with displaying."
  (interactive "p")
  (latex-math-preview-set-current-insert-mode)
  (latex-math-preview-insert-symbol-base num))

(defun latex-math-preview-symbols-of-other-page ()
  "Change other page."
  (interactive)
  (latex-math-preview-quit-window)
  (latex-math-preview-insert-symbol -1))

(defun latex-math-preview-get-current-page-number (key)
  "Get number of page for DATASET."
  (let* ((symbol-datasets (latex-math-preview-insertion-current-symbol-datasets)))
    (catch :find-key
      (dotimes (n (length symbol-datasets))
	(when (string= key (car (nth n symbol-datasets))) (throw :find-key n)))
      nil)))

(defun latex-math-preview-next-candidates-for-insertion (num)
  "Next page of candidates buffer for insertion."
  (interactive "p")
  (let* ((page (latex-math-preview-get-current-page-number
		(latex-math-preview-insertion-get-current-page-key)))
	 (symbol-datasets (latex-math-preview-insertion-current-symbol-datasets))
	 (len (length symbol-datasets))
	 (sign (if (< num 0) -1 1)))
    (while (< num 0) (setq num (+ num len)))
    (when page
      (let ((dataset (car (nth (% (+ page num) len) symbol-datasets))))
	(latex-math-preview-quit-window)
	(latex-math-preview-create-buffer-for-insertion dataset sign)))))

(defun latex-math-preview-previous-candidates-for-insertion (num)
  "Previous page of candidates buffer for insertion."
  (interactive "p")
  (latex-math-preview-next-candidates-for-insertion (- 0 num)))

(defun latex-math-preview-toggle-window-maximization ()
  "Toggle maximization of window displaying candidates of mathematical symbols."
  (interactive)
  (setq latex-math-preview-always-maximize-window (not latex-math-preview-always-maximize-window))
  (latex-math-preview-quit-window)
  (latex-math-preview-create-buffer-for-insertion
   (latex-math-preview-insertion-get-current-page-key)))

(defun latex-math-preview-put-selected-candidate ()
  "Insert selected LaTeX mathematical symboled to original buffer."
  (interactive)
  (let ((sym (get-text-property (point) 'latex-math-preview-symbol)))
    (when sym
      (latex-math-preview-quit-window)
      (latex-math-preview-symbol-insert-item sym)
      (let* ((val (assoc latex-math-preview-current-insert-mode latex-math-preview-recent-inserted-symbol))
	     (list-cdr (cons sym (delete sym (cdr val)))))
	(when (> (length list-cdr) latex-math-preview-recent-inserted-symbol-number)
	  (setf (nthcdr latex-math-preview-recent-inserted-symbol-number list-cdr) nil))
	(setcdr val list-cdr)))))

(defun latex-math-preview-put-candidate-mouse-selecting (event)
  "Insert mouse selecting candidate."
  (interactive "e")
  (mouse-set-point event)
  (latex-math-preview-set-overlay-for-selected-item)
  (latex-math-preview-put-selected-candidate))

(defun latex-math-preview-delete-current-cache ()
  "Delete cache and make cache again."
  (interactive)
  (let ((key (latex-math-preview-insertion-get-current-page-key)))
    (latex-math-preview-quit-window)
    (latex-math-preview-clear-cache-for-insertion key)
    (latex-math-preview-create-buffer-for-insertion key))) 

;;;###autoload
(defun latex-math-preview-last-symbol-again ()
  "Insert last symbol which is inserted by `latex-math-preview-insert-symbol'"
  (interactive)
  (latex-math-preview-set-current-insert-mode)
  (let ((last-symbol (cadr (assq latex-math-preview-current-insert-mode
				 latex-math-preview-recent-inserted-symbol))))
    (if last-symbol (latex-math-preview-symbol-insert-item last-symbol))))

(defun latex-math-preview-symbol-recent-used-text ()
  (list (list "Recent Used" nil
	      (cdr (assq 'text latex-math-preview-recent-inserted-symbol)))))

(defun latex-math-preview-symbol-recent-used-math ()
  (list (list "Recent Used" nil
	      (cdr (assq 'math latex-math-preview-recent-inserted-symbol)))))

;;-----------------------------------------------------------------------------
;; Move to other item

(defun latex-math-preview-set-overlay-for-selected-item ()
  "Set overlay and highlight."
  (save-excursion
    (let ((start-ol))
      (skip-chars-backward "^\t")
      (setq start-ol (point))
      (re-search-forward "  " nil t)
      (skip-chars-backward " ")
      (if latex-math-preview-selection-overlay-for-insertion
	  (move-overlay latex-math-preview-selection-overlay-for-insertion start-ol (point))
	(progn
	  (setq latex-math-preview-selection-overlay-for-insertion (make-overlay start-ol (point)))
	  (overlay-put latex-math-preview-selection-overlay-for-insertion 'face latex-math-preview-selection-face-for-insertion))))))

(defun latex-math-preview-candidate-for-insertion-point-p ()
  (eq (get-text-property (point) 'face) 'latex-math-preview-candidate-for-insertion-face))

(defun latex-math-preview-goto-right-of-item ()
  (while (and (not (eobp)) (latex-math-preview-candidate-for-insertion-point-p))
    (forward-char 1))
  (while (and (not (eobp)) (not (latex-math-preview-candidate-for-insertion-point-p)))
    (forward-char 1)))

(defun latex-math-preview-goto-left-of-item ()
  (while (and (not (bobp)) (latex-math-preview-candidate-for-insertion-point-p))
    (backward-char 1))
  (while (and (not (bobp)) (not (latex-math-preview-candidate-for-insertion-point-p)))
    (backward-char 1)))

(defun latex-math-preview-move-to-right-item ()
  "Move to right item."
  (interactive)
  (latex-math-preview-goto-right-of-item)
  (if (latex-math-preview-candidate-for-insertion-point-p)
      (latex-math-preview-set-overlay-for-selected-item)
    (latex-math-preview-move-to-left-item)))

(defun latex-math-preview-move-to-left-item ()
  "Move to left item."
  (interactive)
  (latex-math-preview-goto-left-of-item)
  (if (latex-math-preview-candidate-for-insertion-point-p)
      (latex-math-preview-set-overlay-for-selected-item)
    (latex-math-preview-move-to-right-item)))

(defun latex-math-preview-move-to-upward-item ()
  "Move to upward item."
  (interactive)
  (let ((item-col (get-text-property (point) 'latex-math-preview-symbol-column))
	(item-line-new (1- (get-text-property (point) 'latex-math-preview-symbol-line)))
	(start-pt (point)))
    (when (>= item-line-new 1)
      (while (and (not (bobp)) (not (= item-line-new (get-text-property (point) 'latex-math-preview-symbol-line))))
	(latex-math-preview-goto-left-of-item))
      (while (and (not (bobp)) (< item-col (get-text-property (point) 'latex-math-preview-symbol-column)))
	(latex-math-preview-goto-left-of-item))
      (latex-math-preview-set-overlay-for-selected-item))))

(defun latex-math-preview-move-to-downward-item ()
  "Move to downward item."
  (interactive)
  (let ((item-col (get-text-property (point) 'latex-math-preview-symbol-column))
	(item-line-new (1+ (get-text-property (point) 'latex-math-preview-symbol-line)))
	(start-pt (point)))
    (when (>= item-line-new 1)
      (catch 'nonexistent
	(while (and (not (eobp)) (not (= item-line-new (get-text-property (point) 'latex-math-preview-symbol-line))))
	  (latex-math-preview-goto-right-of-item)
	  (unless (latex-math-preview-candidate-for-insertion-point-p)
	    (goto-char start-pt)
	    (latex-math-preview-set-overlay-for-selected-item)
	    (throw 'nonexistent t)))
	(dotimes (n (1- item-col))
	  (latex-math-preview-goto-right-of-item))
	(when (or (not (latex-math-preview-candidate-for-insertion-point-p))
		  (not (= item-line-new (get-text-property (point) 'latex-math-preview-symbol-line))))
	  (while (and (not (bobp)) (not (= item-line-new (get-text-property (point) 'latex-math-preview-symbol-line))))
	    (latex-math-preview-goto-left-of-item))))
      (latex-math-preview-set-overlay-for-selected-item))))

(defun latex-math-preview-move-to-current-line-first-item ()
  "Move to first item in current line."
  (interactive)
  (dotimes (n (1- (get-text-property (point) 'latex-math-preview-symbol-column)))
    (latex-math-preview-goto-left-of-item))
  (latex-math-preview-set-overlay-for-selected-item))

(defun latex-math-preview-move-to-current-line-last-item ()
  "Move to last item in current line."
  (interactive)
  (let ((item-line (get-text-property (point) 'latex-math-preview-symbol-line)))
    (catch :next-line
      (dotimes (n (- latex-math-preview-insert-symbol-column-size
		     (get-text-property (point) 'latex-math-preview-symbol-column)))
	(latex-math-preview-goto-right-of-item)
	(when (or (not (latex-math-preview-candidate-for-insertion-point-p))
		  (not (= item-line (get-text-property (point) 'latex-math-preview-symbol-line))))
	  (latex-math-preview-goto-left-of-item)
	  (throw :next-line t))))
    (latex-math-preview-set-overlay-for-selected-item)))

(defun latex-math-preview-move-to-beginning-of-candidates ()
  "Move to first candidate item in current buffer."
  (interactive)
  (goto-char (point-min))
  (latex-math-preview-move-to-right-item))

(defun latex-math-preview-move-to-end-of-candidates ()
  "Move to last candidate item in current buffer."
  (interactive)
  (goto-char (point-max))
  (latex-math-preview-move-to-left-item))

(defun latex-math-preview-scroll-up ()
  "Scroll up and move to nearestd item."
  (interactive)
  (let ((item-col (get-text-property (point) 'latex-math-preview-symbol-column))
	(item-line (get-text-property (point) 'latex-math-preview-symbol-line)))
    (scroll-up)
    (unless (latex-math-preview-candidate-for-insertion-point-p)
      (latex-math-preview-goto-right-of-item))
    (latex-math-preview-set-overlay-for-selected-item)))

(defun latex-math-preview-scroll-down ()
  "Scroll down and move to nearestd item."
  (interactive)
  (scroll-down)
  (unless (latex-math-preview-candidate-for-insertion-point-p)
    (latex-math-preview-move-to-right-item))
  (latex-math-preview-set-overlay-for-selected-item))

(defvar latex-math-preview-insert-isearch-map
  (let ((map (copy-keymap isearch-mode-map)))
    (define-key map (kbd "<return>") 'latex-math-preview-insert-isearch-exit)
    map)
  "Keymap for latex-math-preview-insert-isearch.")

(defun latex-math-preview-insert-isearch-exit ()
  "Search insertion item."
  (interactive)
  (latex-math-preview-set-overlay-for-selected-item)
  (isearch-exit))

(defun latex-math-preview-insert-isearch-forward ()
  (interactive)
  (let ((isearch-mode-map latex-math-preview-insert-isearch-map))
    (isearch-forward)))

(defun latex-math-preview-insert-isearch-backward ()
  (interactive)
  (let ((isearch-mode-map latex-math-preview-insert-isearch-map))
    (isearch-backward)))

;;-----------------------------------------------------------------------------
;; Preview beamer frame

(defun latex-math-preview-search-beamer-frame-region ()
  (let (beg end)
    (if (and transient-mark-mode mark-active)
	(progn
	  (setq beg (region-beginning))
	  (setq end (region-end))
	  (setq mark-active nil))
      (save-excursion
	(let ((start-point (point)))
	  (when (search-backward "\\begin{frame}" nil t)
	    (setq beg (point))
	    (if (and (search-forward "\\end{frame}" nil t) (< start-point (point)))
		(setq end (point))))
	  (when (not (and beg end))
	    (goto-char start-point)
	    (when (search-backward-regexp "\\\\frame[^a-z]" nil t)
	      (setq beg (point))
	      (catch :finish-search
		(let ((count 0))
		  (when (search-forward "{" nil t)
		    (forward-char)
		    (while (not (eobp))
		      (skip-chars-forward "^{}")
		      (cond
		       ((looking-at "{")
			(forward-char)
			(setq count (1+ count)))
		       ((looking-at "}")
			(forward-char)
			(if (= 0 count)
			    (progn
			      (setq end (point))
			      (throw :finish-search t))
			  (setq count (1- count))))
		       (t (throw :finish-search t))))))))))))
    (if (and beg end) (buffer-substring-no-properties beg end) nil)))

(defun latex-math-preview-search-beamer-preamble ()
  (save-excursion
    (let (preamble)
      (goto-char (point-min))
      (when (search-forward "\\begin{document}" nil t)
	(search-backward "\\begin{document}" nil t)
	(setq preamble (buffer-substring-no-properties (point-min) (point))))
      preamble)))

(defun latex-math-preview-make-temporary-beamer-tex-file ()
  (let ((preamble (latex-math-preview-search-beamer-preamble))
	(frame (latex-math-preview-search-beamer-frame-region)))
    (if (and preamble frame)
	(let ((dot-tex (latex-math-preview-create-temporary-tex-filename))
	      (coding-system buffer-file-coding-system))
	  (with-temp-file dot-tex
	    (insert preamble)
	    (insert "\\begin{document}\n" frame "\n\\end{document}")
	    (set-buffer-file-coding-system coding-system)
	    dot-tex))
      nil)))

;;;###autoload
(defun latex-math-preview-beamer-frame ()
  "Display beamer frame at current position."
  (interactive)
  (let ((dot-tex (latex-math-preview-make-temporary-beamer-tex-file)))
    (if dot-tex
	(let ((png (apply 'latex-math-preview-successive-convert dot-tex latex-math-preview-beamer-to-png)))
	  (if png
	      (latex-math-preview-png-image png (current-window-configuration))
	    (latex-math-preview-raise-can-not-create-image dot-tex)))
      (message "Here is no beamer frame.")))
  (latex-math-preview-clear-working-directory))

(provide 'latex-math-preview)

;;; latex-math-preview.el ends here
