import cherrypy
import hashlib
import os
import pathlib
import requests
import shelve
import shutil

content_host = "https://cadence.moe"

db = None
def init_database():
	global db
	db = shelve.open("crumpet_server_config", writeback=False)
	db.setdefault("game_directory", None)
	db.setdefault("customlevels_directory", None)
	db.setdefault("is_installed", True)

try:
	init_database()
except:
	# database corruption error? HOW??? do I actually need to close the file like it told me
	# because I don't know how to close the file like it told me
	print("resetting server configuration due to database corruption")
	db.close()
	os.unlink("crumpet_server_config")
	init_database()

def hash_file(filename):
	h = hashlib.sha256()
	b = bytearray(h.block_size)
	mv = memoryview(b)

	with open(filename, "rb") as file:
		for n in iter(lambda: file.readinto(mv), 0):
			h.update(mv[:n])

	return h

def check_game_path(game_path):
	if not game_path.exists() or not game_path.is_dir():
		return {
			"status": "failure",
			"message": "Directory does not exist."
		}
	res2_path = game_path.joinpath("res2.dat")
	if not res2_path.exists() or res2_path.is_dir():
		return {
			"status": "failure",
			"message": "Directory exists, but does not contain res2.dat."
		}
	return None

def open_level(filename, mode):
	return open(os.path.join(db["customlevels_directory"], filename), mode)

def restricted_message():
	return "This action is restricted. You can enable this action by installing Crumpet on your own computer."

def autodetect_game_directory():
	return None # placeholder

class Crumpet:
	def _cp_dispatch(self, vpath):
		if vpath[:2] == ["api", "rtw"]:
			vpath[:2] = []
			return self

		return vpath

	@cherrypy.expose
	@cherrypy.tools.json_out()
	def get_paths(self):
		# Check game directory
		game_directory = db["game_directory"]
		if game_directory:
			game_path = pathlib.Path(game_directory)
			problem = check_game_path(game_path)
			if problem:
				game_directory = autodetect_game_directory()
		# do not need to check customlevels directory since the interface should replace whatever is sent.
		customlevels_directory = db["customlevels_directory"]
		return {
			"game_directory": game_directory,
			"customlevels_directory": customlevels_directory
		}

	@cherrypy.expose
	@cherrypy.tools.json_in()
	@cherrypy.tools.json_out()
	def save_game_directory(self):
		try:
			root = cherrypy.request.json
		except AttributeError:
			return {
				"status": "failure",
				"message": "Requires JSON POST input."
			}
		if type(root.get("value")) != str:
			return {
				"status": "failure",
				"message": "Requires `value` string parameter in JSON."
			}
		game_directory = root["value"]
		# Check that the game is there
		game_path = pathlib.Path(game_directory)
		if not game_path.exists() or not game_path.is_dir():
			return {
				"status": "failure",
				"message": "Directory does not exist."
			}
		res2_path = game_path.joinpath("res2.dat")
		if not res2_path.exists() or res2_path.is_dir():
			return {
				"status": "failure",
				"message": "Directory exists, but does not contain res2.dat."
			}
		db["game_directory"] = game_directory
		return {
			"status": "success"
		}

	@cherrypy.expose
	@cherrypy.tools.json_in()
	@cherrypy.tools.json_out()
	def save_customlevels_directory(self):
		try:
			root = cherrypy.request.json
		except AttributeError:
			return {
				"status": "failure",
				"message": "Requires JSON POST input."
			}
		if type(root.get("value")) != str:
			return {
				"status": "failure",
				"message": "Requires `value` string parameter in JSON."
			}
		customlevels_directory = root["value"]
		# Check that the directory is there
		customlevels_path = pathlib.Path(customlevels_directory)
		if not customlevels_path.exists() or not customlevels_path.is_dir():
			return {
				"status": "failure",
				"message": "Directory does not exist."
			}
		db["customlevels_directory"] = customlevels_directory
		return {
			"status": "success"
		}

	@cherrypy.expose
	@cherrypy.tools.json_out()
	def request_images(self, *path_components):
		# Request a token
		token_request = requests.get(content_host + "/api/rtw/token")
		token = token_request.content
		# print("token is: {}".format(token))

		# Hash the file
		game_directory = db["game_directory"]
		res2_path = pathlib.Path(game_directory).joinpath("res2.dat")
		if not res2_path.exists() or res2_path.is_dir():
			return {
				"status": "failure",
				"message": "Could not locate res2.dat."
			}
		h = hash_file(res2_path.absolute())
		# print("original hash is: {}".format(h.hexdigest()))

		# Update the hash with the token
		h.update(token)
		patched_hash = h.hexdigest()
		# print("patched hash is: {}".format(patched_hash))

		# Ask for images
		download_url = content_host + "/api/rtw/fetchimages?token={}&hash={}".format(token.decode(), patched_hash)
		images_request = requests.get(download_url)
		if images_request.status_code != 200:
			return {
				"status": "failure",
				"message": images_request.content
			}

		output_filename = pathlib.Path(__file__).parent.joinpath("images.zip").absolute()
		with open(output_filename, "wb") as fd:
			for chunk in images_request.iter_content(128):
				fd.write(chunk)

		unpack_directory = pathlib.Path(__file__).parent.joinpath("root").absolute()
		shutil.unpack_archive(output_filename, unpack_directory)

		return {
			"status": "success"
		}

	@cherrypy.expose
	@cherrypy.tools.json_in()
	def download(self):
		if not db["is_installed"]:
			return restricted_message()
		root = cherrypy.request.json
		level_data = bytearray(root["data"])
		filename = root["filename"]
		with open_level(filename, "wb") as fd:
			fd.write(level_data)
		cherrypy.response.status = 204

	@cherrypy.expose
	@cherrypy.tools.json_out()
	def load(self, /, filename):
		with open_level(filename, "rb") as fd:
			level_data = fd.read()
		return list(level_data)

server_root = pathlib.Path(__file__).parent.joinpath("root")
cherrypy.config.update({"server.socket_port": 3456, "server.socket_host": "0.0.0.0"})
cherrypy.quickstart(Crumpet(), "/", {
	"/": {
		"tools.staticdir.on": True,
		"tools.staticdir.dir": str(server_root.absolute()),
		"tools.staticdir.index": "index.html"
	}
})