import io
import logging

import PIL
import PIL.Image

try:
    from gi.repository import GLib
    GLIB_AVAILABLE = True
except (ValueError, ImportError):
    GLIB_AVAILABLE = False

try:
    import gi
    gi.require_version('GdkPixbuf', '2.0')
    from gi.repository import GdkPixbuf
    GDK_PIXBUF_AVAILABLE = True
except (ValueError, ImportError):
    GDK_PIXBUF_AVAILABLE = False


import openpaperwork_core
import openpaperwork_core.deps

from .. import deps


LOGGER = logging.getLogger(__name__)


class Plugin(openpaperwork_core.PluginBase):
    def get_interfaces(self):
        return [
            'chkdeps',
            'pixbuf_pillow',
        ]

    def chkdeps(self, out: dict):
        if not GLIB_AVAILABLE:
            out['glib'].update(openpaperwork_core.deps.GLIB)
        if not GDK_PIXBUF_AVAILABLE:
            out['gdk_pixbuf'].update(deps.GDK_PIXBUF)

    @staticmethod
    def pixbuf_to_pillow(pixbuf):
        (width, height) = (pixbuf.get_width(), pixbuf.get_height())
        pixels = pixbuf.get_pixels()
        colors = "RGB"
        if (width * height * 4 == len(pixels)):
            colors = "RGBA"
        return PIL.Image.frombytes(
            colors,
            (width, height),
            pixbuf.get_pixels()
        )

    def pillow_to_pixbuf(self, img):
        """
        Convert an image object to a GDK pixbuf
        """
        if not GDK_PIXBUF_AVAILABLE:
            return None

        if img is None:
            return None
        img = img.convert("RGB")

        if hasattr(GdkPixbuf.Pixbuf, 'new_from_bytes'):
            data = GLib.Bytes.new(img.tobytes())
            (width, height) = img.size
            return GdkPixbuf.Pixbuf.new_from_bytes(
                data, GdkPixbuf.Colorspace.RGB,
                False, 8, width, height, width * 3
            )

        file_desc = io.BytesIO()
        try:
            img.save(file_desc, "ppm")
            contents = file_desc.getvalue()
        finally:
            file_desc.close()
        loader = GdkPixbuf.PixbufLoader.new_with_type("pnm")
        try:
            loader.write(contents)
            pixbuf = loader.get_pixbuf()
        finally:
            loader.close()
        return pixbuf
