#!/usr/bin/python3.7

import sys
import os
import imtools
import gettext
import _thread as thread
import subprocess
import tempfile
import locale
import time
import hashlib
import mimetypes
import pickle
from io import BytesIO
from xml.etree import ElementTree

from PIL import Image
import gi
gi.require_version("Gtk", "3.0")
from gi.repository import Gio, Gtk, GObject, Gdk, GdkPixbuf, Pango, GLib

import config
from SettingsWidgets import SidePage
from xapp.GSettingsWidgets import *

gettext.install("cinnamon", "/usr/share/locale")

BACKGROUND_COLOR_SHADING_TYPES = [
    ("solid", _("Solid color")),
    ("horizontal", _("Horizontal gradient")),
    ("vertical", _("Vertical gradient"))
]

BACKGROUND_PICTURE_OPTIONS = [
    ("none", _("No picture")),
    ("wallpaper", _("Mosaic")),
    ("centered", _("Centered")),
    ("scaled", _("Scaled")),
    ("stretched", _("Stretched")),
    ("zoom", _("Zoom")),
    ("spanned", _("Spanned"))
]

BACKGROUND_ICONS_SIZE = 100

BACKGROUND_COLLECTION_TYPE_DIRECTORY = "directory"
BACKGROUND_COLLECTION_TYPE_XML = "xml"

# even though pickle supports higher protocol versions, we want to version 2 because it's the latest
# version supported by python2 which (at this time) is still used by older versions of Cinnamon.
# When those versions are no longer supported, we can consider using a newer version.
PICKLE_PROTOCOL_VERSION = 2

(STORE_IS_SEPARATOR, STORE_ICON, STORE_NAME, STORE_PATH, STORE_TYPE) = range(5)

# EXIF utility functions (source: http://stackoverflow.com/questions/4228530/pil-thumbnail-is-rotating-my-image)
def flip_horizontal(im): return im.transpose(Image.FLIP_LEFT_RIGHT)
def flip_vertical(im): return im.transpose(Image.FLIP_TOP_BOTTOM)
def rotate_180(im): return im.transpose(Image.ROTATE_180)
def rotate_90(im): return im.transpose(Image.ROTATE_90)
def rotate_270(im): return im.transpose(Image.ROTATE_270)
def transpose(im): return rotate_90(flip_horizontal(im))
def transverse(im): return rotate_90(flip_vertical(im))
orientation_funcs = [None,
                     lambda x: x,
                     flip_horizontal,
                     rotate_180,
                     flip_vertical,
                     transpose,
                     rotate_270,
                     transverse,
                     rotate_90
                     ]
def apply_orientation(im):
    """
    Extract the oritentation EXIF tag from the image, which should be a PIL Image instance,
    and if there is an orientation tag that would rotate the image, apply that rotation to
    the Image instance given to do an in-place rotation.

    :param Image im: Image instance to inspect
    :return: A possibly transposed image instance
    """

    try:
        kOrientationEXIFTag = 0x0112
        if hasattr(im, '_getexif'): # only present in JPEGs
            e = im._getexif()       # returns None if no EXIF data
            if e is not None:
                #log.info('EXIF data found: %r', e)
                orientation = e[kOrientationEXIFTag]
                f = orientation_funcs[orientation]
                return f(im)
    except:
        # We'd be here with an invalid orientation value or some random error?
        pass # log.exception("Error applying EXIF Orientation tag")
    return im


class ColorsWidget(SettingsWidget):
    def __init__(self, size_group):
        super(ColorsWidget, self).__init__(dep_key=None)

        #gsettings
        self.settings = Gio.Settings("org.cinnamon.desktop.background")

        # settings widgets
        combo = Gtk.ComboBox()
        key = 'color-shading-type'
        value = self.settings.get_string(key)
        renderer_text = Gtk.CellRendererText()
        combo.pack_start(renderer_text, True)
        combo.add_attribute(renderer_text, "text", 1)
        model = Gtk.ListStore(str, str)
        combo.set_model(model)
        combo.set_id_column(0)
        for option in BACKGROUND_COLOR_SHADING_TYPES:
            iter = model.append([option[0], option[1]])
            if value == option[0]:
                combo.set_active_iter(iter)
        combo.connect('changed', self.on_combo_changed, key)

        self.content_widget = Gtk.Box(valign=Gtk.Align.CENTER)
        self.content_widget.pack_start(combo, False, False, 2)

        # Primary color
        for key in ['primary-color', 'secondary-color']:
            color_button = Gtk.ColorButton()
            color_button.set_use_alpha(True)
            rgba = Gdk.RGBA()
            rgba.parse(self.settings.get_string(key))
            color_button.set_rgba(rgba)
            color_button.connect('color-set', self.on_color_changed, key)
            self.content_widget.pack_start(color_button, False, False, 2)

        # Keep a ref on the second color button (so we can hide/show it when appropriate)
        self.color2_button = color_button
        self.color2_button.set_no_show_all(True)
        self.show_or_hide_color2(value)
        self.add_to_size_group(size_group)
        self.label = SettingsLabel(_("Background color"))
        self.pack_start(self.label, False, False, 0)
        self.pack_end(self.content_widget, False, False, 0)

    def on_color_changed(self, widget, key):
        color_string = widget.get_color().to_string()
        self.settings.set_string(key, color_string)

    def on_combo_changed(self, widget, key):
        tree_iter = widget.get_active_iter()
        if tree_iter != None:
            value = widget.get_model()[tree_iter][0]
            self.settings.set_string(key, value)
            self.show_or_hide_color2(value)

    def show_or_hide_color2(self, value):
        if (value == 'solid'):
            self.color2_button.hide()
        else:
            self.color2_button.show()

class Module:
    name = "backgrounds"
    category = "appear"
    comment = _("Change your desktop's background")

    def __init__(self, content_box):
        keywords = _("background, picture, screenshot, slideshow")
        self.sidePage = SidePage(_("Backgrounds"), "cs-backgrounds", keywords, content_box, module=self)

    def on_module_selected(self):
        if not self.loaded:
            print("Loading Backgrounds module")

            self.sidePage.stack = SettingsStack()
            self.sidePage.add_widget(self.sidePage.stack)

            self.shown_collection = None  # Which collection is displayed in the UI

            self._background_schema = Gio.Settings(schema="org.cinnamon.desktop.background")
            self._slideshow_schema = Gio.Settings(schema="org.cinnamon.desktop.background.slideshow")
            self._slideshow_schema.connect("changed::slideshow-enabled", self.on_slideshow_enabled_changed)
            self.add_folder_dialog = Gtk.FileChooserDialog(title=_("Add Folder"),
                                                           action=Gtk.FileChooserAction.SELECT_FOLDER,
                                                           buttons=(Gtk.STOCK_CANCEL, Gtk.ResponseType.CANCEL,
                                                                    Gtk.STOCK_OPEN, Gtk.ResponseType.OK))

            self.xdg_pictures_directory = os.path.expanduser("~/Pictures")
            xdg_config = os.path.expanduser("~/.config/user-dirs.dirs")
            if os.path.exists(xdg_config) and os.path.exists("/usr/bin/xdg-user-dir"):
                path = subprocess.check_output(["xdg-user-dir", "PICTURES"]).decode("utf-8").rstrip("\n")
                if os.path.exists(path):
                    self.xdg_pictures_directory = path

            self.get_user_backgrounds()

            # Images

            mainbox = Gtk.Box.new(Gtk.Orientation.HORIZONTAL, 2)
            mainbox.expand = True
            mainbox.set_border_width(8)

            self.sidePage.stack.add_titled(mainbox, "images", _("Images"))

            left_vbox = Gtk.Box.new(Gtk.Orientation.VERTICAL, 0)
            right_vbox = Gtk.Box.new(Gtk.Orientation.VERTICAL, 0)

            folder_scroller = Gtk.ScrolledWindow.new(None, None)
            folder_scroller.set_shadow_type(Gtk.ShadowType.IN)
            folder_scroller.set_policy(Gtk.PolicyType.AUTOMATIC, Gtk.PolicyType.AUTOMATIC)
            folder_scroller.set_property("min-content-width", 150)

            self.folder_tree = Gtk.TreeView.new()
            self.folder_tree.set_headers_visible(False)
            folder_scroller.add(self.folder_tree)

            button_toolbar = Gtk.Toolbar.new()
            button_toolbar.set_icon_size(1)
            Gtk.StyleContext.add_class(Gtk.Widget.get_style_context(button_toolbar), "inline-toolbar")
            self.add_folder_button = Gtk.ToolButton.new(None, None)
            self.add_folder_button.set_icon_name("list-add-symbolic")
            self.add_folder_button.set_tooltip_text(_("Add new folder"))
            self.add_folder_button.connect("clicked", lambda w: self.add_new_folder())
            self.remove_folder_button = Gtk.ToolButton.new(None, None)
            self.remove_folder_button.set_icon_name("list-remove-symbolic")
            self.remove_folder_button.set_tooltip_text(_("Remove selected folder"))
            self.remove_folder_button.connect("clicked", lambda w: self.remove_folder())
            button_toolbar.insert(self.add_folder_button, 0)
            button_toolbar.insert(self.remove_folder_button, 1)

            image_scroller = Gtk.ScrolledWindow.new(None, None)
            image_scroller.set_shadow_type(Gtk.ShadowType.IN)
            image_scroller.set_policy(Gtk.PolicyType.AUTOMATIC, Gtk.PolicyType.AUTOMATIC)

            self.icon_view = ThreadedIconView()
            image_scroller.add(self.icon_view)
            self.icon_view.connect("selection-changed", self.on_wallpaper_selection_changed)

            right_vbox.pack_start(image_scroller, True, True, 0)
            left_vbox.pack_start(folder_scroller, True, True, 0)
            left_vbox.pack_start(button_toolbar, False, False, 0)

            mainbox.pack_start(left_vbox, False, False, 2)
            mainbox.pack_start(right_vbox, True, True, 2)

            left_vbox.set_border_width(2)
            right_vbox.set_border_width(2)

            self.collection_store = Gtk.ListStore(bool,    # is separator
                                                  str,     # Icon name
                                                  str,     # Display name
                                                  str,     # Path
                                                  str)     # Type of collection
            cell = Gtk.CellRendererText()
            cell.set_alignment(0, 0)
            pb_cell = Gtk.CellRendererPixbuf()
            self.folder_column = Gtk.TreeViewColumn()
            self.folder_column.pack_start(pb_cell, False)
            self.folder_column.pack_start(cell, True)
            self.folder_column.add_attribute(pb_cell, "icon-name", 1)
            self.folder_column.add_attribute(cell, "text", 2)

            self.folder_column.set_alignment(0)

            self.folder_tree.append_column(self.folder_column)
            self.folder_tree.connect("cursor-changed", self.on_folder_source_changed)

            self.get_system_backgrounds()

            tree_separator = [True, None, None, None, None]
            self.collection_store.append(tree_separator)

            if len(self.user_backgrounds) > 0:
                for item in self.user_backgrounds:
                    self.collection_store.append(item)

            self.folder_tree.set_model(self.collection_store)
            self.folder_tree.set_row_separator_func(self.is_row_separator, None)

            self.get_initial_path()

            # Settings

            page = SettingsPage()

            settings = page.add_section(_("Background Settings"))

            size_group = Gtk.SizeGroup.new(Gtk.SizeGroupMode.HORIZONTAL)

            self.sidePage.stack.add_titled(page, "settings", _("Settings"))

            widget = GSettingsSwitch(_("Play backgrounds as a slideshow"), "org.cinnamon.desktop.background.slideshow", "slideshow-enabled")
            settings.add_row(widget)

            widget = GSettingsSpinButton(_("Delay"), "org.cinnamon.desktop.background.slideshow", "delay", _("minutes"), 1, 1440)
            settings.add_reveal_row(widget, "org.cinnamon.desktop.background.slideshow", "slideshow-enabled")

            widget = GSettingsSwitch(_("Play images in random order"), "org.cinnamon.desktop.background.slideshow", "random-order")
            settings.add_reveal_row(widget, "org.cinnamon.desktop.background.slideshow", "slideshow-enabled")

            widget = GSettingsComboBox(_("Picture aspect"), "org.cinnamon.desktop.background", "picture-options", BACKGROUND_PICTURE_OPTIONS, size_group=size_group)
            settings.add_row(widget)

            widget = ColorsWidget(size_group)
            settings.add_row(widget)

    def is_row_separator(self, model, iter, data):
        return model.get_value(iter, 0)

    def on_slideshow_enabled_changed(self, settings, key):
        if self._slideshow_schema.get_boolean("slideshow-enabled"):
            self.icon_view.set_sensitive(False)
            self.icon_view.set_selection_mode(Gtk.SelectionMode.NONE)
        else:
            self.icon_view.set_sensitive(True)
            self.icon_view.set_selection_mode(Gtk.SelectionMode.SINGLE)

    def get_system_backgrounds(self):
        picture_list = []
        folder_list = []
        properties_dir = "/usr/share/gnome-background-properties"
        backgrounds = []
        if os.path.exists(properties_dir):
            for i in os.listdir(properties_dir):
                if i.endswith(".xml"):
                    xml_path = os.path.join(properties_dir, i)
                    display_name = i.replace(".xml", "").replace("-", " ").replace("_", " ").split(" ")[-1].capitalize()
                    icon = "preferences-desktop-wallpaper-symbolic"
                    order = 10
                    # Special case for Linux Mint. We don't want to use 'start-here' here as it wouldn't work depending on the theme.
                    # Also, other distros should get equal treatment. If they define cinnamon-backgrounds and use their own distro name, we should add support for it.
                    if display_name == "Retro":
                        icon = "document-open-recent-symbolic"
                        order = 20 # place retro bgs at the end
                    if display_name == "Linuxmint":
                        display_name = "Linux Mint"
                        icon = "linuxmint-logo-badge-symbolic"
                        order = 0
                    backgrounds.append([[False, icon, display_name, xml_path, BACKGROUND_COLLECTION_TYPE_XML], display_name, order])

        backgrounds.sort(key=lambda x: (x[2], x[1]))
        for background in backgrounds:
            self.collection_store.append(background[0])

    def get_user_backgrounds(self):
        self.user_backgrounds = []
        path = os.path.expanduser("~/.cinnamon/backgrounds/user-folders.lst")
        if os.path.exists(path):
            with open(path) as f:
                folders = f.readlines()
            for line in folders:
                folder_path = line.strip("\n")
                folder_name = folder_path.split("/")[-1]
                if folder_path == self.xdg_pictures_directory:
                    icon = "folder-pictures-symbolic"
                else:
                    icon = "folder-symbolic"
                self.user_backgrounds.append([False, icon, folder_name, folder_path, BACKGROUND_COLLECTION_TYPE_DIRECTORY])
        else:
            # Add XDG PICTURE DIR
            self.user_backgrounds.append([False, "folder-pictures-symbolic", self.xdg_pictures_directory.split("/")[-1], self.xdg_pictures_directory, BACKGROUND_COLLECTION_TYPE_DIRECTORY])
            self.update_folder_list()

    def format_source(self, type, path):
        # returns 'type://path'
        return ("%s://%s" % (type, path))

    def get_initial_path(self):
        try:
            image_source = self._slideshow_schema.get_string("image-source")
            tree_iter = self.collection_store.get_iter_first()
            collection = self.collection_store[tree_iter]
            collection_type = collection[STORE_TYPE]
            collection_path = collection[STORE_PATH]
            collection_source = self.format_source(collection_type, collection_path)
            self.remove_folder_button.set_sensitive(True)

            if image_source != "" and "://" in image_source:
                while tree_iter != None:
                    if collection_source == image_source:
                        tree_path = self.collection_store.get_path(tree_iter)
                        self.folder_tree.set_cursor(tree_path)
                        if collection_type == BACKGROUND_COLLECTION_TYPE_XML:
                            self.remove_folder_button.set_sensitive(False)
                        self.update_icon_view(collection_path, collection_type)
                        return
                    tree_iter = self.collection_store.iter_next(tree_iter)
                    collection = self.collection_store[tree_iter]
                    collection_type = collection[STORE_TYPE]
                    collection_path = collection[STORE_PATH]
                    collection_source = self.format_source(collection_type, collection_path)
            else:
                self._slideshow_schema.set_string("image-source", collection_source)
                tree_path = self.collection_store.get_path(tree_iter)
                self.folder_tree.get_selection().select_path(tree_path)
                if collection_type == BACKGROUND_COLLECTION_TYPE_XML:
                    self.remove_folder_button.set_sensitive(False)
                self.update_icon_view(collection_path, collection_type)
        except Exception as detail:
            print(detail)

    def on_row_activated(self, tree, path, column):
        self.folder_tree.set_selection(path)

    def on_folder_source_changed(self, tree):
        self.remove_folder_button.set_sensitive(True)
        if tree.get_selection() is not None:
            folder_paths, iter = tree.get_selection().get_selected()
            if iter:
                collection_path = folder_paths[iter][STORE_PATH]
                collection_type = folder_paths[iter][STORE_TYPE]
                collection_source = self.format_source(collection_type, collection_path)
                if os.path.exists(collection_path):
                    if collection_source != self._slideshow_schema.get_string("image-source"):
                        self._slideshow_schema.set_string("image-source", collection_source)
                    if collection_type == BACKGROUND_COLLECTION_TYPE_XML:
                        self.remove_folder_button.set_sensitive(False)
                    self.update_icon_view(collection_path, collection_type)

    def get_selected_wallpaper(self):
        selected_items = self.icon_view.get_selected_items()
        if len(selected_items) == 1:
            path = selected_items[0]
            iter = self.icon_view.get_model().get_iter(path)
            return self.icon_view.get_model().get(iter, 0)[0]
        return None

    def on_wallpaper_selection_changed(self, iconview):
        wallpaper = self.get_selected_wallpaper()
        if wallpaper:
            for key in wallpaper:
                if key == "filename":
                    self._background_schema.set_string("picture-uri", "file://" + wallpaper[key])
                elif key == "options":
                    self._background_schema.set_string("picture-options", wallpaper[key])

    def add_new_folder(self):
        res = self.add_folder_dialog.run()
        if res == Gtk.ResponseType.OK:
            folder_path = self.add_folder_dialog.get_filename()
            folder_name = folder_path.split("/")[-1]
            # Make sure it's not already added..
            for background in self.user_backgrounds:
                if background[STORE_PATH] == folder_path:
                    self.add_folder_dialog.hide()
                    return
            if folder_path == self.xdg_pictures_directory:
                icon = "folder-pictures-symbolic"
            else:
                icon = "folder-symbolic"
            self.user_backgrounds.append([False, icon, folder_name, folder_path, BACKGROUND_COLLECTION_TYPE_DIRECTORY])
            self.collection_store.append([False, icon, folder_name, folder_path, BACKGROUND_COLLECTION_TYPE_DIRECTORY])
            self.update_folder_list()
        self.add_folder_dialog.hide()

    def remove_folder(self):
        if self.folder_tree.get_selection() is not None:
            self.icon_view.clear()
            folder_paths, iter = self.folder_tree.get_selection().get_selected()
            if iter:
                path = folder_paths[iter][STORE_PATH]
                self.collection_store.remove(iter)
                for item in self.user_backgrounds:
                    if item[STORE_PATH] == path:
                        self.user_backgrounds.remove(item)
                        self.update_folder_list()
                        break

    def update_folder_list(self):
        path = os.path.expanduser("~/.cinnamon/backgrounds")
        if not os.path.exists(path):
            os.makedirs(path, mode=0o755, exist_ok=True)
        path = os.path.expanduser("~/.cinnamon/backgrounds/user-folders.lst")
        if len(self.user_backgrounds) == 0:
            file_data = ""
        else:
            first_path = self.user_backgrounds[0][STORE_PATH]
            file_data = first_path + "\n"
            for folder in self.user_backgrounds:
                if folder[STORE_PATH] == first_path:
                    continue
                else:
                    file_data += "%s\n" % folder[STORE_PATH]

        with open(path, "w") as f:
            f.write(file_data)

    def update_icon_view(self, path=None, type=None):
        if path != self.shown_collection:
            self.shown_collection = path
            picture_list = []
            if os.path.exists(path):
                if type == BACKGROUND_COLLECTION_TYPE_DIRECTORY:
                    files = os.listdir(path)
                    files.sort()
                    for i in files:
                        filename = os.path.join(path, i)
                        picture_list.append({"filename": filename})
                elif type == BACKGROUND_COLLECTION_TYPE_XML:
                    picture_list += self.parse_xml_backgrounds_list(path)

            self.icon_view.set_pictures_list(picture_list, path)
            if self._slideshow_schema.get_boolean("slideshow-enabled"):
                self.icon_view.set_sensitive(False)
            else:
                self.icon_view.set_sensitive(True)

    def splitLocaleCode(self, localeCode):
        try:
            loc = localeCode.partition("_")
            loc = (loc[0], loc[2])
        except:
            loc = ("en", "US")
        return loc

    def getLocalWallpaperName(self, names, loc):
        result = ""
        mainLocFound = False
        for wp in names:
            wpLoc = wp[0]
            wpName = wp[1]
            if wpLoc == ("", ""):
                if not mainLocFound:
                    result = wpName
            elif wpLoc[0] == loc[0]:
                if wpLoc[1] == loc[1]:
                    return wpName
                elif wpLoc[1] == "":
                    result = wpName
                    mainLocFound = True
        return result

    def parse_xml_backgrounds_list(self, filename):
        try:
            locAttrName = "{http://www.w3.org/XML/1998/namespace}lang"
            loc = self.splitLocaleCode(locale.getdefaultlocale()[0])
            res = []
            subLocaleFound = False
            f = open(filename)
            rootNode = ElementTree.fromstring(f.read())
            f.close()
            if rootNode.tag == "wallpapers":
                for wallpaperNode in rootNode:
                    if wallpaperNode.tag == "wallpaper" and wallpaperNode.get("deleted") != "true":
                        wallpaperData = {"metadataFile": filename}
                        names = []
                        for prop in wallpaperNode:
                            if type(prop.tag) == str:
                                if prop.tag != "name":
                                    wallpaperData[prop.tag] = prop.text
                                else:
                                    propAttr = prop.attrib
                                    wpName = prop.text
                                    locName = self.splitLocaleCode(propAttr.get(locAttrName)) if locAttrName in propAttr else ("", "")
                                    names.append((locName, wpName))
                        wallpaperData["name"] = self.getLocalWallpaperName(names, loc)

                        if "filename" in wallpaperData and wallpaperData["filename"] != "" and os.path.exists(wallpaperData["filename"]) and os.access(wallpaperData["filename"], os.R_OK):
                            if wallpaperData["name"] == "":
                                wallpaperData["name"] = os.path.basename(wallpaperData["filename"])
                            res.append(wallpaperData)
            return res
        except Exception as detail:
            print("Could not parse %s!" % filename)
            print(detail)
            return []

class PixCache(object):

    def __init__(self):
        self._data = {}

    def get_pix(self, filename, size=None):
        if filename is None:
            return None
        mimetype = mimetypes.guess_type(filename)[0]
        if mimetype is None or not mimetype.startswith("image/"):
            return None

        if filename not in self._data:
            self._data[filename] = {}
        if size in self._data[filename]:
            pix = self._data[filename][size]
        else:
            try:
                h = hashlib.sha1(('%f%s' % (os.path.getmtime(filename), filename)).encode()).hexdigest()
                tmp_cache_path = GLib.get_user_cache_dir() + '/cs_backgrounds/'
                if not os.path.exists(tmp_cache_path):
                    os.mkdir(tmp_cache_path)
                cache_filename = tmp_cache_path + h + "v2"

                loaded = False
                if os.path.exists(cache_filename):
                    # load from disk cache
                    try:
                        with open(cache_filename, "rb") as cache_file:
                            pix = pickle.load(cache_file)
                        tmp_img = Image.open(BytesIO(pix[0]))
                        pix[0] = self._image_to_pixbuf(tmp_img)
                        loaded = True
                    except Exception as detail:
                        # most likely either the file is corrupted, or the file was pickled using the
                        # python2 version of cinnamon settings. Either way, we want to ditch the current
                        # cache file and generate a new one. This is still backward compatible with older
                        # Cinnamon versions
                        os.remove(cache_filename)

                if not loaded:
                    if mimetype == "image/svg+xml":
                        # rasterize svg with Gdk-Pixbuf and convert to PIL Image
                        tmp_pix = GdkPixbuf.Pixbuf.new_from_file(filename)
                        mode = "RGBA" if tmp_pix.props.has_alpha else "RGB"
                        img = Image.frombytes(mode, (tmp_pix.props.width, tmp_pix.props.height),
                                              tmp_pix.read_pixel_bytes().get_data(), "raw",
                                              mode, tmp_pix.props.rowstride)
                    else:
                        img = Image.open(filename)
                        img = apply_orientation(img)

                    # generate thumbnail
                    (width, height) = img.size
                    if img.mode != "RGB":
                        if img.mode == "RGBA":
                            bg_img = Image.new("RGBA", img.size, (255,255,255,255))
                            img = Image.alpha_composite(bg_img, img)
                        img = img.convert("RGB")
                    if size:
                        img.thumbnail((size, size), Image.ANTIALIAS)
                    img = imtools.round_image(img, {}, False, None, 3, 255)
                    img = imtools.drop_shadow(img, 4, 4, background_color=(255, 255, 255, 0),
                                              shadow_color=0x444444, border=8, shadow_blur=3,
                                              force_background_color=False, cache=None)

                    # save to disk cache
                    try:
                        png_bytes = BytesIO()
                        img.save(png_bytes, "png")
                        with open(cache_filename, "wb") as cache_file:
                            pickle.dump([png_bytes.getvalue(), width, height], cache_file, PICKLE_PROTOCOL_VERSION)
                    except Exception as detail:
                        print("Failed to save cache file: %s: %s" % (cache_filename, detail))

                    pix = [self._image_to_pixbuf(img), width, height]
            except Exception as detail:
                print("Failed to convert %s: %s" % (filename, detail))
                pix = None
            if pix:
                self._data[filename][size] = pix
        return pix

    # Convert RGBA PIL Image to Pixbuf
    def _image_to_pixbuf(self, img):
        [w, h] = img.size
        return GdkPixbuf.Pixbuf.new_from_bytes(GLib.Bytes.new(img.tobytes()),
                                               GdkPixbuf.Colorspace.RGB,
                                               True, 8, w, h,
                                               w * 4)

PIX_CACHE = PixCache()


class ThreadedIconView(Gtk.IconView):

    def __init__(self):
        Gtk.IconView.__init__(self)
        self.set_item_width(BACKGROUND_ICONS_SIZE * 1.1)
        self._model = Gtk.ListStore(object, GdkPixbuf.Pixbuf, str, str)
        self._model_filter = self._model.filter_new()
        self._model_filter.set_visible_func(self.visible_func)
        self.set_model(self._model_filter)

        area = self.get_area()

        self.current_path = None

        pixbuf_renderer = Gtk.CellRendererPixbuf()
        text_renderer = Gtk.CellRendererText(ellipsize=Pango.EllipsizeMode.END)

        text_renderer.set_alignment(.5, .5)
        area.pack_start(pixbuf_renderer, True, False, False)
        area.pack_start(text_renderer, True, False, False)
        self.add_attribute(pixbuf_renderer, "pixbuf", 1)
        self.add_attribute(text_renderer, "markup", 2)
        text_renderer.set_property("alignment", Pango.Alignment.CENTER)

        self._loading_queue = []
        self._loading_queue_lock = thread.allocate_lock()

        self._loading_lock = thread.allocate_lock()
        self._loading = False

        self._loaded_data = []
        self._loaded_data_lock = thread.allocate_lock()

    def visible_func(self, model, iter, data=None):
        item_path = model.get_value(iter, 3)
        return item_path == self.current_path

    def set_pictures_list(self, pictures_list, path=None):
        self.clear()
        self.current_path = path
        for i in pictures_list:
            self.add_picture(i, path)

    def clear(self):
        self._loading_queue_lock.acquire()
        self._loading_queue = []
        self._loading_queue_lock.release()

        self._loading_lock.acquire()
        is_loading = self._loading
        self._loading_lock.release()
        while is_loading:
            time.sleep(0.1)
            self._loading_lock.acquire()
            is_loading = self._loading
            self._loading_lock.release()

        self._model.clear()

    def add_picture(self, picture, path):
        self._loading_queue_lock.acquire()
        self._loading_queue.append(picture)
        self._loading_queue_lock.release()

        start_loading = False
        self._loading_lock.acquire()
        if not self._loading:
            self._loading = True
            start_loading = True
        self._loading_lock.release()

        if start_loading:
            GLib.timeout_add(100, self._check_loading_progress)
            thread.start_new_thread(self._do_load, (path,))

    def _check_loading_progress(self):
        self._loading_lock.acquire()
        self._loaded_data_lock.acquire()
        res = self._loading
        to_load = []
        while len(self._loaded_data) > 0:
            to_load.append(self._loaded_data[0])
            self._loaded_data = self._loaded_data[1:]
        self._loading_lock.release()
        self._loaded_data_lock.release()

        for i in to_load:
            self._model.append(i)

        return res

    def _do_load(self, path):
        finished = False
        while not finished:
            self._loading_queue_lock.acquire()
            if len(self._loading_queue) == 0:
                finished = True
            else:
                to_load = self._loading_queue[0]
                self._loading_queue = self._loading_queue[1:]
            self._loading_queue_lock.release()
            if not finished:
                filename = to_load["filename"]
                if filename.endswith(".xml"):
                    filename = self.getFirstFileFromBackgroundXml(filename)
                pix = PIX_CACHE.get_pix(filename, BACKGROUND_ICONS_SIZE)
                if pix != None:
                    if "name" in to_load:
                        label = to_load["name"]
                    else:
                        label = os.path.split(to_load["filename"])[1]
                    if "artist" in to_load:
                        artist = "%s\n" % to_load["artist"]
                    else:
                        artist = ""
                    dimensions = "%dx%d" % (pix[1], pix[2])

                    self._loaded_data_lock.acquire()
                    self._loaded_data.append((to_load, pix[0], "<b>%s</b>\n<sub>%s%s</sub>" % (label, artist, dimensions), path))
                    self._loaded_data_lock.release()

        self._loading_lock.acquire()
        self._loading = False
        self._loading_lock.release()

    def getFirstFileFromBackgroundXml(self, filename):
        try:
            f = open(filename)
            rootNode = ElementTree.fromstring(f.read())
            f.close()
            if rootNode.tag == "background":
                for backgroundNode in rootNode:
                    if backgroundNode.tag == "static":
                        for staticNode in backgroundNode:
                            if staticNode.tag == "file":
                                if len(staticNode) > 0 and staticNode[-1].tag == "size":
                                    return staticNode[-1].text
                                return staticNode.text
            print("Could not find filename in %s" % filename)
            return None
        except Exception as detail:
            print("Failed to read filename from %s: %s" % (filename, detail))
            return None
