import re
import sys
import gzip
import urllib.request as request
import urllib.parse as parse
import urllib.error
import os.path

from pyquery import PyQuery as pq

import pirate.data

from io import BytesIO


parser_regex = r'"(magnet\:\?xt=[^"]*)|<td align="right">([^<]+)</td>'


def parse_category(printer, category):
    try:
        category = int(category)
    except ValueError:
        pass
    if category in pirate.data.categories.values():
        return category
    elif category in pirate.data.categories.keys():
        return pirate.data.categories[category]
    else:
        printer.print('Invalid category ignored', color='WARN')
        return 0


def parse_sort(printer, sort):
    try:
        sort = int(sort)
    except ValueError:
        pass
    if sort in pirate.data.sorts.values():
        return sort
    elif sort in pirate.data.sorts.keys():
        return pirate.data.sorts[sort]
    else:
        printer.print('Invalid sort ignored', color='WARN')
        return 99


# TODO: warn users when using a sort in a mode that doesn't accept sorts
# TODO: warn users when using search terms in a mode that doesn't accept search terms
# TODO: same with page parameter for top and top48h
# TODO: warn the user if trying to use a minor category with top48h
def build_request_path(page, category, sort, mode, terms):
    if mode == 'browse':
        if(category == 0):
            category = 100
        return '/browse/{}/{}/{}'.format(category, page, sort)
    elif mode == 'recent':
        # This is not a typo. There is no / between 48h and the category.
        path = '/top/48h'
        # only major categories can be used with this mode
        if(category == 0):
            return path + 'all'
        else:
            return path + str(category)
    elif mode == 'top':
        path = '/top/'
        if(category == 0):
            return path + 'all'
        else:
            return path + str(category)
    elif mode == 'search':
        query = urllib.parse.quote_plus(' '.join(terms))
        return '/search/{}/{}/{}/{}'.format(query, page, sort, category)
    else:
        raise Exception('Unknown mode.')


# this returns a list of dictionaries
def parse_page(html):
    d = pq(html)

    results = []
    # parse the rows one by one
    for row in d('table#searchResult tr'):
        drow = d(row)
        if len(drow('th')) > 0:
            continue

        # grab info about the row
        magnet = pq(drow(':eq(0)>td:nth-child(2)>a:nth-child(2)')[0]).attr('href')
        seeds = pq(drow(':eq(0)>td:nth-child(3)')).text()
        leechers = pq(drow(':eq(0)>td:nth-child(4)')).text()
        id_ = pq(drow('.detLink')).attr('href').split('/')[2]

        # parse descriptions separately
        desc_text = pq(drow('font.detDesc')[0]).text()
        size = re.findall(r'(?<=Size )[0-9.]+\s[KMGT]*[i ]*B', desc_text)[0].split()
        uploaded = re.findall(r'(?<=Uploaded ).+(?=\, Size)', desc_text)[0]

        results.append({
            'magnet': magnet,
            'seeds': seeds,
            'leechers': leechers,
            'size': size,
            'uploaded': uploaded,
            'id': id_
        })

    # check for a blocked mirror
    no_results = re.search(r'No hits\. Try adding an asterisk in '
                           r'you search phrase\.', html)
    if len(results) == 0 and no_results is None:
        # Contradiction - we found no results,
        # but the page didn't say there were no results.
        # The page is probably not actually the pirate bay,
        # so let's try another mirror
        raise IOError('Blocked mirror detected.')

    return results


def remote(printer, pages, category, sort, mode, terms, mirror):
    res_l = []

    if pages < 1:
        raise ValueError('Please provide an integer greater than 0 '
                         'for the number of pages to fetch.')

    # Catch the Ctrl-C exception and exit cleanly
    try:
        for page in range(pages):
            path = build_request_path(page, category, sort, mode, terms)

            req = request.Request(mirror + path,
                                  headers=pirate.data.default_headers)
            req.add_header('Accept-encoding', 'gzip')
            f = request.urlopen(req, timeout=pirate.data.default_timeout)
            if f.info().get('Content-Encoding') == 'gzip':
                f = gzip.GzipFile(fileobj=BytesIO(f.read()))
            res = f.read().decode('utf-8')

            res_l += parse_page(res)

    except KeyboardInterrupt:
        printer.print('\nCancelled.')
        sys.exit(0)

    return res_l


def get_torrent(info_hash):
    url = 'http://torcache.net/torrent/{:X}.torrent'
    req = request.Request(url.format(info_hash),
                          headers=pirate.data.default_headers)
    req.add_header('Accept-encoding', 'gzip')

    torrent = request.urlopen(req, timeout=pirate.data.default_timeout)
    if torrent.info().get('Content-Encoding') == 'gzip':
        torrent = gzip.GzipFile(fileobj=BytesIO(torrent.read()))

    return torrent.read()


def save_torrents(printer, chosen_links, results, folder):
    for link in chosen_links:
        magnet = results[link]['magnet']
        name = re.search(r'dn=([^\&]*)', magnet)
        torrent_name = parse.unquote(name.group(1)).replace('+', ' ')
        info_hash = int(re.search(r'btih:([a-f0-9]{40})', magnet).group(1), 16)
        torrent_name = torrent_name.replace('/', '_').replace('\\', '_')
        file = os.path.join(folder, torrent_name + '.torrent')

        try:
            torrent = get_torrent(info_hash)
        except urllib.error.HTTPError:
            printer.print('There is no cached file for this torrent :(', color='ERROR')
        else:
            open(file, 'wb').write(torrent)
            printer.print('Saved {:X} in {}'.format(info_hash, file))


def save_magnets(printer, chosen_links, results, folder):
    for link in chosen_links:
        magnet = results[link]['magnet']
        name = re.search(r'dn=([^\&]*)', magnet)
        torrent_name = parse.unquote(name.group(1)).replace('+', ' ')
        info_hash = int(re.search(r'btih:([a-f0-9]{40})', magnet).group(1), 16)
        torrent_name = torrent_name.replace('/', '_').replace('\\', '_')
        file = os.path.join(folder,  torrent_name + '.magnet')

        printer.print('Saved {:X} in {}'.format(info_hash, file))
        with open(file, 'w') as f:
            f.write(magnet + '\n')