SickGear/sickbeard/image_cache.py

# Author: Nic Wolfe <nic@wolfeden.ca>
# URL: http://code.google.com/p/sickbeard/
#
# This file is part of SickRage.
#
# SickRage is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# SickRage is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with SickRage.  If not, see <http://www.gnu.org/licenses/>.

import os.path

import sickbeard

from sickbeard import helpers, logger, exceptions
from sickbeard import encodingKludge as ek

from sickbeard.metadata.generic import GenericMetadata

from lib.hachoir_parser import createParser
from lib.hachoir_metadata import extractMetadata


class ImageCache:
    def __init__(self):
        pass

    def __del__(self):
        pass

    def _cache_dir(self):
        """
        Builds up the full path to the image cache directory
        """
        return ek.ek(os.path.abspath, ek.ek(os.path.join, sickbeard.CACHE_DIR, 'images'))

    def _thumbnails_dir(self):
        """
        Builds up the full path to the thumbnails image cache directory
        """
        return ek.ek(os.path.abspath, ek.ek(os.path.join, self._cache_dir(), 'thumbnails'))

    def poster_path(self, indexer_id):
        """
        Builds up the path to a poster cache for a given Indexer ID

        returns: a full path to the cached poster file for the given Indexer ID
        
        indexer_id: ID of the show to use in the file name
        """
        poster_file_name = str(indexer_id) + '.poster.jpg'
        return ek.ek(os.path.join, self._cache_dir(), poster_file_name)

    def banner_path(self, indexer_id):
        """
        Builds up the path to a banner cache for a given Indexer ID

        returns: a full path to the cached banner file for the given Indexer ID
        
        indexer_id: ID of the show to use in the file name
        """
        banner_file_name = str(indexer_id) + '.banner.jpg'
        return ek.ek(os.path.join, self._cache_dir(), banner_file_name)

    def poster_thumb_path(self, indexer_id):
        """
        Builds up the path to a poster cache for a given Indexer ID

        returns: a full path to the cached poster file for the given Indexer ID
        
        indexer_id: ID of the show to use in the file name
        """
        posterthumb_file_name = str(indexer_id) + '.poster.jpg'
        return ek.ek(os.path.join, self._thumbnails_dir(), posterthumb_file_name)

    def banner_thumb_path(self, indexer_id):
        """
        Builds up the path to a poster cache for a given Indexer ID

        returns: a full path to the cached poster file for the given Indexer ID
        
        indexer_id: ID of the show to use in the file name
        """
        bannerthumb_file_name = str(indexer_id) + '.banner.jpg'
        return ek.ek(os.path.join, self._thumbnails_dir(), bannerthumb_file_name)

    def has_poster(self, indexer_id):
        """
        Returns true if a cached poster exists for the given Indexer ID
        """
        poster_path = self.poster_path(indexer_id)
        logger.log(u"Checking if file " + str(poster_path) + " exists", logger.DEBUG)
        return ek.ek(os.path.isfile, poster_path)

    def has_banner(self, indexer_id):
        """
        Returns true if a cached banner exists for the given Indexer ID
        """
        banner_path = self.banner_path(indexer_id)
        logger.log(u"Checking if file " + str(banner_path) + " exists", logger.DEBUG)
        return ek.ek(os.path.isfile, banner_path)

    def has_poster_thumbnail(self, indexer_id):
        """
        Returns true if a cached poster thumbnail exists for the given Indexer ID
        """
        poster_thumb_path = self.poster_thumb_path(indexer_id)
        logger.log(u"Checking if file " + str(poster_thumb_path) + " exists", logger.DEBUG)
        return ek.ek(os.path.isfile, poster_thumb_path)

    def has_banner_thumbnail(self, indexer_id):
        """
        Returns true if a cached banner exists for the given Indexer ID
        """
        banner_thumb_path = self.banner_thumb_path(indexer_id)
        logger.log(u"Checking if file " + str(banner_thumb_path) + " exists", logger.DEBUG)
        return ek.ek(os.path.isfile, banner_thumb_path)


    BANNER = 1
    POSTER = 2
    BANNER_THUMB = 3
    POSTER_THUMB = 4

    def which_type(self, path):
        """
        Analyzes the image provided and attempts to determine whether it is a poster or banner.
        
        returns: BANNER, POSTER if it concluded one or the other, or None if the image was neither (or didn't exist)
        
        path: full path to the image
        """

        if not ek.ek(os.path.isfile, path):
            logger.log(u"Couldn't check the type of " + str(path) + " cause it doesn't exist", logger.WARNING)
            return None

        # use hachoir to parse the image for us
        img_parser = createParser(path)
        img_metadata = extractMetadata(img_parser)

        if not img_metadata:
            logger.log(u"Unable to get metadata from " + str(path) + ", not using your existing image", logger.DEBUG)
            return None

        img_ratio = float(img_metadata.get('width')) / float(img_metadata.get('height'))

        img_parser.stream._input.close()

        # most posters are around 0.68 width/height ratio (eg. 680/1000)
        if 0.55 < img_ratio < 0.8:
            return self.POSTER

        # most banners are around 5.4 width/height ratio (eg. 758/140)
        elif 5 < img_ratio < 6:
            return self.BANNER
        else:
            logger.log(u"Image has size ratio of " + str(img_ratio) + ", unknown type", logger.WARNING)
            return None

    def _cache_image_from_file(self, image_path, img_type, indexer_id):
        """
        Takes the image provided and copies it to the cache folder
        
        returns: bool representing success
        
        image_path: path to the image we're caching
        img_type: BANNER or POSTER
        indexer_id: id of the show this image belongs to
        """

        # generate the path based on the type & indexer_id
        if img_type == self.POSTER:
            dest_path = self.poster_path(indexer_id)
        elif img_type == self.BANNER:
            dest_path = self.banner_path(indexer_id)
        else:
            logger.log(u"Invalid cache image type: " + str(img_type), logger.ERROR)
            return False

        # make sure the cache folder exists before we try copying to it
        if not ek.ek(os.path.isdir, self._cache_dir()):
            logger.log(u"Image cache dir didn't exist, creating it at " + str(self._cache_dir()))
            ek.ek(os.makedirs, self._cache_dir())

        if not ek.ek(os.path.isdir, self._thumbnails_dir()):
            logger.log(u"Thumbnails cache dir didn't exist, creating it at " + str(self._thumbnails_dir()))
            ek.ek(os.makedirs, self._thumbnails_dir())

        logger.log(u"Copying from " + image_path + " to " + dest_path)
        helpers.copyFile(image_path, dest_path)

        return True

    def _cache_image_from_indexer(self, show_obj, img_type):
        """
        Retrieves an image of the type specified from indexer and saves it to the cache folder
        
        returns: bool representing success
        
        show_obj: TVShow object that we want to cache an image for
        img_type: BANNER or POSTER
        """

        # generate the path based on the type & indexer_id
        if img_type == self.POSTER:
            img_type_name = 'poster'
            dest_path = self.poster_path(show_obj.indexerid)
        elif img_type == self.BANNER:
            img_type_name = 'banner'
            dest_path = self.banner_path(show_obj.indexerid)
        elif img_type == self.POSTER_THUMB:
            img_type_name = 'poster_thumb'
            dest_path = self.poster_thumb_path(show_obj.indexerid)
        elif img_type == self.BANNER_THUMB:
            img_type_name = 'banner_thumb'
            dest_path = self.banner_thumb_path(show_obj.indexerid)
        else:
            logger.log(u"Invalid cache image type: " + str(img_type), logger.ERROR)
            return False

        # retrieve the image from indexer using the generic metadata class
        #TODO: refactor
        metadata_generator = GenericMetadata()
        img_data = metadata_generator._retrieve_show_image(img_type_name, show_obj)
        result = metadata_generator._write_image(img_data, dest_path)

        return result

    def fill_cache(self, show_obj):
        """
        Caches all images for the given show. Copies them from the show dir if possible, or
        downloads them from indexer if they aren't in the show dir.
        
        show_obj: TVShow object to cache images for
        """

        logger.log(u"Checking if we need any cache images for show " + str(show_obj.indexerid), logger.DEBUG)

        # check if the images are already cached or not
        need_images = {self.POSTER: not self.has_poster(show_obj.indexerid),
                       self.BANNER: not self.has_banner(show_obj.indexerid),
                       self.POSTER_THUMB: not self.has_poster_thumbnail(show_obj.indexerid),
                       self.BANNER_THUMB: not self.has_banner_thumbnail(show_obj.indexerid)}

        if not need_images[self.POSTER] and not need_images[self.BANNER] and not need_images[self.POSTER_THUMB] and not \
        need_images[self.BANNER_THUMB]:
            logger.log(u"No new cache images needed, not retrieving new ones")
            return

        # check the show dir for poster or banner images and use them
        if need_images[self.POSTER] or need_images[self.BANNER]:
            try:
                for cur_provider in sickbeard.metadata_provider_dict.values():
                    logger.log(u"Checking if we can use the show image from the " + cur_provider.name + " metadata",
                               logger.DEBUG)
                    if ek.ek(os.path.isfile, cur_provider.get_poster_path(show_obj)):
                        cur_file_name = os.path.abspath(cur_provider.get_poster_path(show_obj))
                        cur_file_type = self.which_type(cur_file_name)

                        if cur_file_type == None:
                            logger.log(u"Unable to retrieve image type, not using the image from " + str(cur_file_name),
                                       logger.WARNING)
                            continue

                        logger.log(u"Checking if image " + cur_file_name + " (type " + str(
                            cur_file_type) + " needs metadata: " + str(need_images[cur_file_type]), logger.DEBUG)

                        if cur_file_type in need_images and need_images[cur_file_type]:
                            logger.log(
                                u"Found an image in the show dir that doesn't exist in the cache, caching it: " + cur_file_name + ", type " + str(
                                    cur_file_type), logger.DEBUG)
                            self._cache_image_from_file(cur_file_name, cur_file_type, show_obj.indexerid)
                            need_images[cur_file_type] = False
            except exceptions.ShowDirNotFoundException:
                logger.log(u"Unable to search for images in show dir because it doesn't exist", logger.WARNING)

        # download from indexer for missing ones
        for cur_image_type in [self.POSTER, self.BANNER, self.POSTER_THUMB, self.BANNER_THUMB]:
            logger.log(u"Seeing if we still need an image of type " + str(cur_image_type) + ": " + str(
                need_images[cur_image_type]), logger.DEBUG)
            if cur_image_type in need_images and need_images[cur_image_type]:
                self._cache_image_from_indexer(show_obj, cur_image_type)

        logger.log(u"Done cache check")