#!/usr/bin/env python3
"""
A script for updating mods in a minecraft modpack.
"""
import os
import re
import sqlite3
from datetime import datetime
from collections import defaultdict

import bs4
import requests

import config_master

_con = sqlite3.connect("modpack.db", detect_types=sqlite3.PARSE_DECLTYPES)
_cur = _con.cursor()

class Mod:
	"""Represents a mod."""
	title = ""
	url = ""
	release_phase = ""
	dl_link = ""
	filename = ""
	upload_date = ""

	def __init__(self, data=()):
		if data:
			self.from_tup(data)

	def from_tup(self, data):
		"""
		Updates the mod's information with that retrieved from the database.
		"""
		self.title = data[0]
		self.url = data[1]
		self.release_phase = data[2]
		self.filename = data[3]
		self.upload_date = data[4]
	
	def save(self):
		"""Inserts the mod into the `mod` table of the database."""
		_cur.execute(
			"INSERT OR REPLACE INTO mod VALUES (?, ?, ?, ?, ?)",
			(
				self.title,
				self.url,
				self.release_phase,
				self.filename,
				self.upload_date
			),
		)
		_con.commit()


def init_db():
	"""
	Initializes the database.
	"""
	try:
		_cur.execute("SELECT * FROM `mod`").fetchone()
		_cur.execute("SELECT * FROM `change_item`").fetchone()
	except sqlite3.OperationalError:
		_cur.execute(
			"CREATE TABLE mod("
			+ "title TEXT PRIMARY KEY,"
			+ "url TEXT,"
			+ "release_phase TEXT,"
			+ "filename TEXT,"
			+ "upload_date TIMESTAMP"
			+ ")"
		)
		_cur.execute(
			"CREATE TABLE change_item("
			+ "date TIMESTAMP DEFAULT CURRENT_TIMESTAMP,"
			+ "text TEXT"
			+ ")"
		)
		_con.commit()


def scrape_curse_forge(url, phase=None):
	"""
	Scrapes all relevent info from the provided mod page and returns a
	mod object.
	"""
	print("Scraping:", url)
	res = requests.get(url, verify=True)
	res.raise_for_status()
	soup = bs4.BeautifulSoup(res.text, "html.parser")
	mod = Mod()

	bar = soup.find("h3", text="Recent Files").parent.parent
	bar = bar.find("div", class_="cf-sidebar-inner")
	hs = bar.find_all("h4")
	h = [h for h in hs if h.text.strip() ==f"Minecraft {config_master.mc_ver}"]
	if not h:
		print("No valid files for this version found.")
		return False
	h = h[0]
	files = bar.contents[bar.contents.index(h)+2].find_all("li")
	if phase:
		for li in files:
			if li.div.div.span.get("title") == phase:
				break
		else:
			print("No valid files for this release phase found.")
			return False
	else:
		li = files[0]

	mod.title = re.search(r"(.*?)- Mods", soup.title.text).group(1).strip()
	mod.url = url
	mod.release_phase = li.div.div.span.get("title")
	mod.dl_link = "https://www.curseforge.com"
	mod.dl_link += li.contents[5].a.get("href") + '/file'
	mod.filename = li.contents[3].a.get("data-name")
	mod.upload_date = datetime.utcfromtimestamp(int(li.abbr.get("data-epoch")))
	return mod


def download_mod(mod):
	"""Downloads the mod."""
	print("Downloading:", mod.filename)
	res = requests.get(mod.dl_link)
	res.raise_for_status()
	fname = res.headers.get('content-disposition')
	if fname:
		mod.filename = re.search(r'filename="(.+)"', fname).group(1)
	else:
		mod.filename = res.url.split('/')[-1]
	with open(os.path.join("mods", mod.filename), 'wb') as file:
		for chunk in res.iter_content(100000):
			file.write(chunk)


def get_mod(target):
	"""Gets the specified mod in the modpack."""
	data = _cur.execute(
		"SELECT * FROM mod WHERE url = ?",
		(target,)
	).fetchone()
	mod = Mod(data)
	return mod


def get_all_mods():
	"""Retrieves all mods from the database."""
	data = _cur.execute("SELECT * FROM mod ORDER BY title ASC").fetchall()
	mods = []
	for line in data:
		mods.append(Mod(line))
	return mods


def log_change(text):
	"""Logs the provided message as a change under today's date."""
	_cur.execute(
		"INSERT INTO change_item(text) VALUES(?)", (text,)
	)
	_con.commit()


def get_all_changes():
	"""Retrieves all change log items."""
	data = _cur.execute(
		"SELECT date(date), text FROM change_item ORDER BY date DESC"
	).fetchall()
	dates = [tup[0] for tup in data]
	data = {date: [tup[1] for tup in data if tup[0] == date] for date in dates}
	return data


def add_mod(target, phase=None):
	"""Adds the specified mod to the modpack."""
	mod = scrape_curse_forge(target, phase)
	download_mod(mod)
	mod.save()
	log_change(f"Added {mod.title}")


def add_mod_all(target):
	"""Reads a list of URLs from a textfile and adds them to the modpack."""
	with open(target, 'r') as file:
		urls = file.read().splitlines()
	for url in urls:
		mod = scrape_curse_forge(url)
		download_mod(mod)
		mod.save()
	log_change(f"Added mods in bulk from {os.path.basename(target)}")


def update_mod(target, delete=False, phase=None):
	"""Updates the specified mod."""
	mod_current = get_mod(target)
	if not phase:
		phase = mod_current.release_phase
	mod_latest = scrape_curse_forge(mod_current.url, phase)
	if mod_latest.upload_date > mod_current.upload_date:
		print(f"Updating {mod_latest.title} to {mod_latest.filename}")
		download_mod(mod_latest)
		mod_latest.save()
		log_change(f"Updated {mod_latest.title} to {mod_latest.filename}")
		if not delete:
			os.makedirs("mods_old", exist_ok=True)
			#os.rename(os.path.join("mods", mod_current.filename),
			#	os.path.join("mods_old", mod_current.filename)
			#)
		else:
			os.remove(os.path.join("mods", mod_current.filename))


def update_mod_all(delete=False):
	"""Updates all mods in the pack."""
	for mod in get_all_mods():
		update_mod(mod.url, delete)


def generate_summary():
	"""Generates the summary HTML file."""
	mods = get_all_mods()
	changes = get_all_changes()
	with open("template.html", 'r') as file:
		html = file.read()

	change_log = ""
	for date, items in changes.items():
		change_log += f"<i>{date}</i><ul>"
		items_sorted = defaultdict(list)
		for item in items:
			action, _, message = item.partition(' ')
			items_sorted[action].append(message)
		for action, messages in items_sorted.items():
			if len(messages) > 10:
				change_log += f"<li>{len(messages)} mods {action.lower()}</li>"
			else:
				for message in messages:
					change_log += f"<li>{action} {message}</li>"
		change_log += "</ul>"

	mod_table = ""
	for mod in mods:
		mod_table += f'<tr><td><a href="{mod.url}">{mod.title}</a></td>'
		mod_table += f'<td>{mod.filename}</td>'
		mod_table += f'<td>{mod.release_phase[0]}</td>'
		mod_table += f'<td>{mod.upload_date.strftime("%Y-%m-%d")}</td></tr>'

	html = html.replace("$$MODPACK$$", config_master.modpack_name)
	html = html.replace("$$CHANGELOG$$", change_log)
	html = html.replace("$$MODTABLE$$", mod_table)

	with open(config_master.modpack_name + ".html", "w") as file:
		file.write(html)


def post_pack():
	"""
	Uploads the modpack to the remote server.
	"""
	generate_summary()
	data = {'password': config_master.password}

	mods = get_all_mods()
	res = requests.get(config_master.remote_addr + '/get')
	res.raise_for_status()
	mods_remote = res.json()
	mods = [mod for mod in mods if mod.filename not in mods_remote]

	for mod in mods:
		files = {}
		files[mod.filename] = open(os.path.join('mods', mod.filename), 'rb')
		res = requests.post(
			url=config_master.remote_addr + '/post',
			data=data,
			files=files
		)
		res.raise_for_status()
		files[mod.filename].close()
		print(f"{mod.filename} uploaded.")


	files = {}
	files['modpack.db'] = open('modpack.db', 'rb')
	files[config_master.modpack_name + '.html'] = open(
		config_master.modpack_name +'.html', 'rb')
	res = requests.post(
		url=config_master.remote_addr + '/post',
		data=data,
		files=files
	)
	res.raise_for_status()
	for file in files.values():
		file.close()
	print("modpack.db uploaded.")
	print(f"{config_master.modpack_name}.html uploaded.")
	print('Success!')


def remove_mod(target, delete):
	"""
	Removes a mod from the modpack.
	"""
	mod = get_mod(target)
	if delete:
		os.remove(os.path.join("mods", mod.filename))
	else:
		os.makedirs("mods_old", exist_ok=True)
		os.rename(os.path.join("mods", mod.filename),
			os.path.join("mods_old", mod.filename))
	_cur.execute("DELETE FROM mod WHERE url = ?", (target,))
	log_change(f"Removed {mod.title}")
	print(f"Removed {mod.title}")


def url_migration():
	"""
	Curseforge changed their urls from `minecraft.curseforge.com/projects/mod`
	to `www.curseforge.com/minecraft/mc-mods/mod`. This function updates
	urls saved in the database to comply with this.
	"""
	for mod in get_all_mods():
		url = 'https://www.curseforge.com/minecraft/mc-mods/'
		url += mod.url.split('/')[-1]
		mod.url = url
		mod.save()


if __name__ == "__main__":
	import argparse

	parser = argparse.ArgumentParser(
		description="A series of tools and functions for managing a "
			"Minecraft modpack.",
	)
	parser.add_argument(
		"action",
		choices=["add", "add_all", "update", "update_all", "summary",
			"post", "remove", "migrate"],
		help="What action to perform.",
	)
	parser.add_argument(
		"target",
		nargs='?',
		help="The mod, mod url, or file containing a list of urls to "
			"work with.",
	)
	parser.add_argument(
		"-p",
		"--phase",
		choices=["Release", "Beta", "Alpha"],
		help="Which release phase to look for."
	)
	parser.add_argument(
		"--delete",
		action="store_true",
		help="Delete the old mod file after downloading the new.",
	)
	args = parser.parse_args()
	os.makedirs("mods", exist_ok=True)
	init_db()

	if args.action == "add":
		add_mod(args.target, args.phase)
	elif args.action == "add_all":
		add_mod_all(args.target)
	elif args.action == "update":
		update_mod(args.target, args.delete, args.phase)
	elif args.action == "update_all":
		update_mod_all(args.delete)
	elif args.action == "summary":
		generate_summary()
	elif args.action == "post":
		post_pack()
	elif args.action == "remove":
		remove_mod(args.target, args.delete)
	elif args.action == "migrate":
		url_migration()