#!/bin/sh

# modified from https://github.com/daveish/png2icns for OSX 10.11

# USAGE

# ./pngToIcns <input png> <outp icns>
# Example
# ./pngToIcns.sh ~/sample.png ~/Desktop/converted.icns

# Exec Paths
SIPS=$(which sips)
ICONUTIL=$(which iconutil)
IMAGEMAGICK=$(which convert)
if [ ! -x "${SIPS}" ]; then
	echo "Cannot find required sips executable" >&2
	exit 1;
fi
if [ ! -x "${ICONUTIL}" ]; then
	echo "Cannot find required iconutil executable" >&2
	exit 1;
fi
if [ ! -x "${IMAGEMAGICK}" ]; then
	echo "Cannot find required ImageMagick Convert executable" >&2
	exit 1;
fi

# Parameters
SOURCE=$1

# Get source image
if [ -z "${SOURCE}" ]; then
	echo "No source image specified"
	exit 1
fi


# File Infrastructure
NAME=$(basename "${SOURCE}")
EXT="${NAME##*.}"
BASE="${NAME%.*}"
ICONSET="${BASE}.iconset"

# Debug Info
# echo "SOURCE: ${SOURCE}"
# echo "NAME: $NAME"
# echo "BASE: $BASE"
# echo "EXT: $EXT"
# echo "ICONSET: $ICONSET"

# Get source image info
SRCWIDTH=$( sips -g pixelWidth "${SOURCE}" | tail -n1 | awk '{print $2}')
SRCHEIGHT=$( sips -g pixelHeight "${SOURCE}" | tail -n1 | awk '{print $2}' )
SRCFORMAT=$( sips -g format "${SOURCE}" | tail -n1 | awk '{print $2}' )

# Debug Info
# echo "SRCWIDTH: $SRCWIDTH"
# echo "SRCHEIGHT: $SRCHEIGHT"
# echo "SRCFORMAT: $SRCFORMAT"

# Check The Source Image
# if [ "x${SRCWIDTH}" != "x1024" ] || [ "x${SRCHEIGHT}" != "x1024" ]; then
# 	echo "ERR: Source image should be 1024 x 1024 pixels." >&2
# 	exit 1;
# fi
if [ "x${SRCFORMAT}" != "xpng" ]; then
	echo "ERR: Source image format should be png." >&2
	exit 1;
fi

# Resample image into iconset
mkdir "${ICONSET}"
# $SIPS -s format png --resampleWidth 1024 "${SOURCE}" --out "${ICONSET}/icon_512x512@2x.png" > /dev/null 2>&1
# $SIPS -s format png --resampleWidth 512 "${SOURCE}" --out "${ICONSET}/icon_512x512.png" > /dev/null 2>&1
# cp  "${ICONSET}/icon_512x512.png"  "${ICONSET}/icon_256x256@2x.png"
# $SIPS -s format png --resampleWidth 256 "${SOURCE}" --out "${ICONSET}/icon_256x256.png" > /dev/null 2>&1
# cp  "${ICONSET}/icon_256x256.png"  "${ICONSET}/icon_128x128@2x.png"
# $SIPS -s format png --resampleWidth 128 "${SOURCE}" --out "${ICONSET}/icon_128x128.png" > /dev/null 2>&1
# $SIPS -s format png --resampleWidth 64 "${SOURCE}" --out "${ICONSET}/icon_32x32@2x.png" > /dev/null 2>&1
# $SIPS -s format png --resampleWidth 32 "${SOURCE}" --out "${ICONSET}/icon_32x32.png" > /dev/null 2>&1
# cp  "${ICONSET}/icon_32x32.png"  "${ICONSET}/icon_16x16@2x.png"
# $SIPS -s format png --resampleWidth 16 "${SOURCE}" --out "${ICONSET}/icon_16x16.png" > /dev/null 2>&1


convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 16x16 "${ICONSET}/icon_16x16.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 32x32 "${ICONSET}/icon_16x16@2x.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 32x32 "${ICONSET}/icon_32x32.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 64x64 "${ICONSET}/icon_32x32@2x.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 128x128 "${ICONSET}/icon_128x128.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 256x256 "${ICONSET}/icon_128x128@2x.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 256x256 "${ICONSET}/icon_256x256.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 512x512 "${ICONSET}/icon_256x256@2x.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 512x512 "${ICONSET}/icon_512x512.png"
convert "${SOURCE}" -define png:big-depth=16 -define png:color-type=6 -sample 1024x1024 "${ICONSET}/icon_512x512@2x.png"


# Create an icns file lefrom the iconset
iconutil -c icns "${ICONSET}" -o $2

# Clean up the iconset
rm -rf "${ICONSET}"