import "hashes/sha256/512bit.code" as sha256
import "utils/multiplexer/256bit.code" as multiplex
import "utils/binary/not.code" as NOT

// Merke-Tree inclusion proof for tree depth 3 

def main(field treeDepth, field[256] rootDigest, private field[256] leafDigest, private field[2] directionSelector, field[256] PathDigest0, private field[256] PathDigest1) -> (field):

	//Setup
	field[256] currentDigest = leafDigest
	field counter = 1
	field currentDirection = 0
	
	//Loop up the tree
	currentDirection = directionSelector[0]
	lhs = multiplex(currentDirection, currentDigest, PathDigest0)
	rhs = multiplex(NOT(currentDirection), currentDigest, PathDigest0)
	currentDigest = sha256(lhs, rhs)
	counter = counter + 1

	currentDirection = directionSelector[1]
	lhs = multiplex(currentDirection, currentDigest, PathDigest1)
	rhs = multiplex(NOT(currentDirection), currentDigest, PathDigest1)
	currentDigest = sha256(lhs, rhs)
	counter = counter + 1

	//Asserts
	counter == treeDepth
	rootDigest == currentDigest

	return 1 //return true in success