#!/usr/bin/env python3

# Requirements:
# pip3 install libscrc pillow

"""
This is free and unencumbered software released into the public domain.

Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.

In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

For more information, please refer to <http://unlicense.org/>
"""

from argparse import ArgumentParser, FileType
from importlib.machinery import SourceFileLoader
from PIL import Image
#from libscrc import modbus
from struct import unpack
from js import document, console, Uint8Array, window, File
from pyodide.ffi import create_proxy
import asyncio
import io
import time

def modbusCrc(msg:str) -> int:
    crc = 0xFFFF
    for n in range(len(msg)):
        crc ^= msg[n]
        for i in range(8):
            if crc & 1:
                crc >>= 1
                crc ^= 0xA001
            else:
                crc >>= 1
    return crc


async def _bannergif(e):
	"""Extracts a DS(i) ROM's icon to an image"""
	# Disable upload, show Loading...
	uploadlabel = document.getElementById("fileUploadLabel")
	uploadlabel.innerHTML = "<b>Loading...</b>"
	uploader = document.getElementById("fileuploadpillow")
	uploader.disabled = True

	#Get the first file from upload
	file_list = e.target.files
	romfile = file_list.item(0)

	if romfile == None:
		# Re-enable upload, hide Loading...
		uploader.disabled = False
		uploader.value = ''
		uploadlabel.innerHTML = "<b>Select your DS(i) ROM!</b>"
		return False
	else:
		#Get the data from the files arrayBuffer as an array of unsigned bytes
		array_buf = Uint8Array.new(await romfile.arrayBuffer())

		#BytesIO wants a bytes-like object, so convert to bytearray first
		bytes_list = bytearray(array_buf)
		rom = io.BytesIO(bytes_list)

		# Seek to banner
		rom.seek(0x68)
		bannerOfs = unpack("<I", rom.read(4))[0]
		rom.seek(bannerOfs)

		# Load version and check checksums
		version, _, _, _, dsiChecksum = unpack("<HHHHH", rom.read(10))

		if version & 0x100:
			rom.seek(bannerOfs + 0x1240)
			data = rom.read(0x1180)
			if dsiChecksum != modbusCrc(data):
				print("Warning: DSi icon checksum failed, using DS icon")
				version &= ~0x100

		rom.seek(bannerOfs)

		# Load banner data
		bitmaps = []
		palettes = []
		animation = []
		if version == 0x103:  # DSi (animated)
			# Read frame bitmaps
			rom.seek(0x1240, io.SEEK_CUR)
			for _ in range(8):
				bitmap = [0] * 32 * 32
				for ty in range(4):
					for tx in range(4):
						for y in range(8):
							for x in range(4):
								byte = unpack("B", rom.read(1))[0]
								bitmap[((ty * 8 + y) * 32) + tx * 8 + x * 2] = byte & 0xF
								bitmap[((ty * 8 + y) * 32) + tx * 8 + x * 2 + 1] = byte >> 4
				bitmaps.append(bitmap)

			# Read palettes
			for _ in range(8):
				palette = [0] * 256 * 3  # Pillow wants a 256 color palette with RGB separated
				for i in range(0x10):
					color = unpack("<H", rom.read(2))[0]
					palette[i * 3] = round((color & 0x1F) * 255 / 31)
					palette[i * 3 + 1] = round(((color >> 5) & 0x1F) * 255 / 31)
					palette[i * 3 + 2] = round(((color >> 10) & 0x1F) * 255 / 31)
				palettes.append(palette)

			# Read animation sequence
			for i in range(0x40):
				value = unpack("<H", rom.read(2))[0]
				animation.append({
					"vflip": True if value & (1 << 15) else False,
					"hflip": True if value & (1 << 14) else False,
					"palette": (value >> 11) & 7,
					"bitmap": (value >> 8) & 7,
					"duration": value & 0xFF
				})
		else:  # DS
			# Read bitmap
			rom.seek(0x20, io.SEEK_CUR)
			bitmap = [0] * 32 * 32
			for ty in range(4):
				for tx in range(4):
					for y in range(8):
						for x in range(4):
							byte = unpack("B", rom.read(1))[0]
							bitmap[((ty * 8 + y) * 32) + tx * 8 + x * 2] = byte & 0xF
							bitmap[((ty * 8 + y) * 32) + tx * 8 + x * 2 + 1] = byte >> 4
			bitmaps.append(bitmap)

			# Read palette
			palette = [0] * 256 * 3  # Pillow wants a 256 color palette with RGB separated
			for i in range(0x10):
				color = unpack("<H", rom.read(2))[0]
				palette[i * 3] = round((color & 0x1F) * 255 / 31)
				palette[i * 3 + 1] = round(((color >> 5) & 0x1F) * 255 / 31)
				palette[i * 3 + 2] = round(((color >> 10) & 0x1F) * 255 / 31)
			palettes.append(palette)

			# No animation, just show the first frame as there's only one
			animation = [{
				"vflip": False,
				"hflip": False,
				"palette": 0,
				"bitmap": 0,
				"duration": 1
			}]

		# Convert to Pillow image
		images = []
		delays = []
		for i, frame in enumerate(animation):
			# Animation ends when the animation u16 is 0, since it's split here
			# for ease of use checking just the duration should be fine
			if frame["duration"] == 0 and i > 0:
				break

			# 32x32 Paletted image
			img = Image.frombytes("P", (32, 32), bytes(bitmaps[frame["bitmap"]]))
			img.putpalette(palettes[frame["palette"]])

			# Flip the image if needed
			if(frame["hflip"]):
				img = img.transpose(Image.FLIP_LEFT_RIGHT)
			if(frame["vflip"]):
				img = img.transpose(Image.FLIP_TOP_BOTTOM)

			conversion = document.getElementById("integer")

			if conversion.value != "1":
				img = img.resize((img.width * int(conversion.value), img.height * int(conversion.value)), resample=None, box=None, reducing_gap=None)

			if conversion.value == "8":
				result = Image.new(img.mode, (320, 320), 0)
				result.putpalette(palettes[frame["palette"]])
				result.paste(img, (32, 32))
				img = result

			#add transparency
			img.info['transparency'] = 0
			img.apply_transparency()

			# Add it to the output list
			delaytime = frame["duration"] * 1000 // 60

			# The 'duration' is in frames (1/60th of a second), Pillow wants
			# miliseconds. This should make sure that frames are never larger
			# than a second but it doesn't seem to work.
			while delaytime > 0:
				if delaytime > 1000:
					images.append(img)
					delays.append(1000)
					delaytime = delaytime - 1000
				else:
					images.append(img)
					delays.append(delaytime)
					delaytime = 0


		# Save output image
		imgformat = document.getElementById("filetype")
		my_stream = io.BytesIO()
		if imgformat.value == "WebP":
			images[0].save(my_stream, format="WEBP", lossless=True, quality=100, save_all=True, append_images=images[1:], duration=delays, loop=0)

			#Create a JS File object with our data and the proper mime type
			image_file = File.new([Uint8Array.new(my_stream.getvalue())], {type: "image/webp" })
			image_file = image_file.slice(0, image_file.size, "image/webp")

			#Create new tag and insert into page
			new_image = document.createElement('img')
			new_image.name = str(int(time.time())) + ".webp"
			new_image.src = window.URL.createObjectURL(image_file)
			document.getElementById("output_upload_pillow").appendChild(new_image)
		else:
			images[0].save(my_stream, format="PNG", save_all=True, append_images=images[1:], duration=delays, loop=0, transparency=0)

			#Create a JS File object with our data and the proper mime type
			image_file = File.new([Uint8Array.new(my_stream.getvalue())], "output.png", {type: "image/apng" })
			image_file = image_file.slice(0, image_file.size, "image/apng")

			#Create new tag and insert into page
			new_image = document.createElement('img')
			new_image.name = str(int(time.time())) + ".png"
			new_image.src = window.URL.createObjectURL(image_file)
			document.getElementById("output_upload_pillow").appendChild(new_image)

		# Re-enable upload, hide Loading...
		uploader.disabled = False
		uploader.value = ''
		uploadlabel.innerHTML = "<b>Select your DS(i) ROM!</b>"


# Run image processing code above whenever file is uploaded
upload_file = create_proxy(_bannergif)
if upload_file != False:
	document.getElementById("fileuploadpillow").addEventListener("change", upload_file)