#!/usr/bin/env python3
"""
Music streaming.
"""
import os
import json
import random
import subprocess
from urllib import parse

from flask import Flask, Response, render_template, send_file, url_for, request, abort

import database
import buckler_flask

FFMPEG_CMD = [
	'ffmpeg', '-y',
	'-loglevel', 'panic',
	'-i', '',
	'-b:a', '64k',
	'-f', 'opus',
	'-'
]


app = Flask(__name__)
app.session_interface = buckler_flask.BucklerSessionInterface()
app.before_request(buckler_flask.require_auth)
database.init_database()

@app.route('/')
def index():
	"""Main index page."""
	artists = database.get_all_artists()
	return render_template('index.html', **locals())


@app.route('/select')
def select():
	"""Retrieve information about an artist, album or track."""
	artist = request.args.get('artist')
	album = request.args.get('album')
	discnumber = request.args.get('discnumber')
	tracknumber = request.args.get('tracknumber')

	if tracknumber:
		result = database.get_track(artist, album, discnumber, tracknumber)
		if not result:
			return ("Valid artist, album, discnumber and tracknumber "
				"parameters must be supplied.")
		else:
			result.pop('filepath')
	elif album:
		result = database.get_album_tracks(artist, album)
		if not result:
			return "Valid artist and album parameters must be supplied."
	elif artist:
		result = database.get_artist_albums(artist)
		if not result:
			return "Valid artist parameter must be supplied."
	else:
		return "Invalid query."
	return json.dumps(result)


@app.route('/select/random')
def select_random():
	"""
	Selects a random track.
	"""
	track = database.get_random_track()
	track.pop('filepath')
	return json.dumps(track)


@app.route('/stream')
def stream():
	"""View for the raw audio file."""
	artist = parse.unquote(request.args.get('artist'))
	album = parse.unquote(request.args.get('album'))
	discnumber = parse.unquote(request.args.get('discnumber'))
	tracknumber = parse.unquote(request.args.get('tracknumber'))

	track = database.get_track(artist, album, discnumber, tracknumber)
	if not track:
		return "Track does not exist."

	FFMPEG_CMD[5] = track['filepath']

	def generate():
		with subprocess.Popen(FFMPEG_CMD, stdout=subprocess.PIPE) as proc:
			data = proc.stdout.read(1024)
			while data:
				yield data
				data = proc.stdout.read(1024)
	return Response(generate(), mimetype="audio/ogg")


@app.route('/coverart')
def coverart():
	"""View for the raw audio file."""
	artist = parse.unquote(request.args.get('artist'))
	album = parse.unquote(request.args.get('album'))
	discnumber = parse.unquote(request.args.get('discnumber'))
	tracknumber = parse.unquote(request.args.get('tracknumber'))

	track = database.get_track(artist, album, discnumber, tracknumber)
	if not track:
		return "Track does not exist."

	cover_path = os.path.join(os.path.dirname(track['filepath']), 'folder.jpg')
	if os.path.isfile(cover_path):
		return send_file(cover_path)
	else:
		return "No cover art for this track found."


if __name__ == "__main__":
	import sys
	if len(sys.argv) > 1:
		database.build_library(database.MUSIC_DIR)
	app.run(host='0.0.0.0', port=5150)