"""
Automatic admin definitions for the videos application.

"""
import datetime
import urlparse

try:
    from urlparse import parse_qs
except ImportError:
    from cgi import parse_qs        # for Python 2.5

from django.contrib import admin
from django.contrib import messages
from gdata.youtube.service import YouTubeService

from videos.models import Playlist


class PlaylistAdmin(admin.ModelAdmin):
    list_display = ['__unicode__', 'playlist_url', 'sync_date']
    readonly_fields = ['playlist_title', 'video_list', 'sync_date']
    actions = ['sync']

    def sync(self, request, queryset):
        for playlist in queryset:
            self.sync_playlist(request, playlist)

    sync.short_description = 'Synchronize with YouTube'

    def sync_playlist(self, request, playlist):
        """
        Retrieve the title and list of videos for a
        YouTube playlist.

        """
        # Find the playlist ID:
        parts = urlparse.urlparse(playlist.playlist_url)
        query = parse_qs(parts.query)
        if 'list' not in query:
            messages.error(request, 'Invalid playlist %s' %
                    playlist.playlist_url)
            return

        playlist_id = query['list'][0]
        if not playlist_id.startswith('PL'):
            messages.error(request, 'Invalid playlist ID in %s' %
                    playlist.playlist_url)
            return
        playlist_id = playlist_id[2:]

        # Get the playlist feed:
        yt = YouTubeService()
        feed = yt.GetYouTubePlaylistVideoFeed(playlist_id=playlist_id)
        feed_title = feed.title.text
        expected_count = int(feed.total_results.text)

        # Get all the videos in the feed; this may take multiple requests:
        vids = []
        while True:
            vids.extend(feed.entry)
            next_link = feed.GetNextLink()
            if not next_link:
                break
            feed = yt.Query(next_link.href)

        if len(vids) != expected_count:
            messages.error(request, "%s: expected %d videos, got %d" %
                    (playlist.playlist_url, expected_count, len(vids)))

        # Find the video ID for each video

        vid_ids = []
        for vid in vids:
            for link in vid.link:
                parts = urlparse.urlparse(link.href)
                query = parse_qs(parts.query)
                if 'v' in query:
                    vid_ids.append(query['v'][0])
                    break
            else:
                messages.error(request, "%s: video id not found for %s" %
                        (playlist.playlist_url, vid.title.text))

        # Okay, save what we got
        playlist.playlist_title = feed_title
        playlist.video_list = ",".join(vid_ids)
        playlist.sync_date = datetime.datetime.now()
        playlist.save()

        messages.info(request, "Synchronized %s (%s)" % (feed_title,
            playlist.playlist_url))


admin.site.register(Playlist, PlaylistAdmin)