#!/bin/sh

# mapGen.sh
#
# Generate a map with ImageMagick from an input text file
#
# Usage: mapGen.sh [-s SIZE] [-f TILE_FOLDER] [-o OUTPUT_FILE] [SOURCE_FILE]

usageMsg="Usage: mapGen.sh [-s SIZE] [-f TILE_FOLDER] [-o OUTPUT_FILE] [SOURCE_FILE]"
cellSize=8
tilesDir="./tiles"
outputFile="out.jpg"

drawMap () {
	mapText=""
	while read line; do
		mapText="${mapText}${line}\n"
	done
	mapText="$(echo "$mapText" | sed 's|\\n|\n|g')"

	height="$(echo "$mapText" | wc -l)"
	width="$(echo "$mapText" | awk '{print length($0)}' | sort -nr | sed 1q)"
	height=$((height*cellSize))
	width=$((width*cellSize))

	[ ! -f "$outputFile" ] && convert -size "$width"x"$height" xc:cyan "$outputFile"

	row=0
	col=0
	echo "$mapText" | (
	while read line; do
		echo "$line" | (
		while read -n1 char; do
			tileFile="$(find $tilesDir -type f -maxdepth 1 | sed 's|.*/||' | grep "^$char" | shuf | sed 1q)"
			if [ -n "$tileFile" ]; then
				tileFile="${tilesDir}/${tileFile}"
				convert "$outputFile" "$tileFile" -geometry +"$col"+"$row" -composite "$outputFile"
			fi
			col=$((col+cellSize))
		done)
		row=$((row+cellSize))
		col=0
	done)
}

while echo "$1" | grep '^-' >/dev/null; do
	case "$1" in
		"-s")
			[ -z "$2" ] && echo "Missing argument for -s. $usageMsg" >&2 && exit 1
			cellSize="$2"
			shift 2
			;;
		"-f")
			[ -z "$2" ] && echo "Missing argument for -f. $usageMsg" >&2 && exit 1
			tilesDir="$2"
			shift 2
			;;
		"-o")
			[ -z "$2" ] && echo "Missing argument for -o. $usageMsg" >&2 && exit 1
			outputFile="$2"
			shift 2
	esac
done

[ ! -d "$tilesDir" ] && echo "Directory not found: $tilesDir" >&2 && exit 1
inputFile="$1"
[ -z "$inputFile" ] && drawMap && exit
[ ! -f "$inputFile" ] && echo "File not found: $inputFile" >&2 && exit 1
drawMap <"$inputFile"