#!/usr/bin/env python3
# This file is part of Xpra.
# Copyright (C) 2018-2021 Antoine Martin <antoine@xpra.org>
# Xpra is released under the terms of the GNU GPL v2, or, at your option, any
# later version. See the file COPYING for details.

import sys
import os.path
from io import BytesIO
from math import cos, sin

from xpra.util import typedict, envint, AdHocStruct, AtomicInteger
from xpra.os_util import WIN32, load_binary_file
from xpra.log import Logger
from xpra.platform.paths import get_icon_filename

log = Logger("opengl", "paint")


def get_gl_client_window_module(force_enable=False):
    log("get_gl_client_window_module()")
    try:
        from xpra.client.gl.gtk3 import nativegl_client_window
    except ImportError as e:
        log("cannot import opengl window module", exc_info=True)
        log.warn("Warning: cannot import native OpenGL module")
        log.warn(" %s", e)
        return {}, None
    opengl_props = nativegl_client_window.check_support(force_enable)
    log("check_support(%s)=%s", force_enable, opengl_props)
    if opengl_props:
        return opengl_props, nativegl_client_window
    return {}, None

def no_scaling(*args):
    if len(args)==1:
        return args[0]
    return args
def get_None(*_args):
    return None
def no_idle_add(fn, *args, **kwargs):
    fn(*args, **kwargs)
def no_timeout_add(*_args, **_kwargs):
    raise Exception("timeout_add should not have been called")
def no_source_remove(*_args, **_kwargs):
    raise Exception("source_remove should not have been called")

class FakeClient(AdHocStruct):
    def __init__(self):
        self.sp = self.sx = self.sy = self.srect = no_scaling
        self.cx = self.cy = no_scaling
        self.xscale = self.yscale = 1
        self.server_window_decorations = True
        self.mmap_enabled = False
        self.mmap = None
        self.readonly = False
        self.encoding_defaults = {}
        self.get_window_frame_sizes = get_None
        self._focused = None
        self.wheel_smooth = False
        self.pointer_grabbed = None
        def noop(*_args):
            """ pretend this method exists and does something """
        self.find_window = noop
        self.request_frame_extents = noop
        self.server_window_states = ()
        self.server_window_frame_extents = False
        self.server_readonly = False
        self.server_pointer = False
        self.update_focus = noop
        self.handle_key_action = noop
        self.window_ungrab = noop
        self.idle_add = no_idle_add
        self.timeout_add = no_timeout_add
        self.source_remove = no_source_remove

    def send(self, *args):
        log("send%s", args)
    def get_current_modifiers(self):
        return ()
    def get_mouse_position(self):
        return 0, 0
    def server_ok(self):
        return True
    def mask_to_names(self, *_args):
        return ()

def test_gl_client_window(gl_client_window_class, max_window_size=(1024, 1024), pixel_depth=24, show=False):
    #try to render using a temporary window:
    draw_result = {}
    window = None
    try:
        x, y = -100, -100
        if show:
            x, y = 100, 100
        w, h = 250, 250
        from xpra.codecs.loader import load_codec
        load_codec("dec_pillow")
        from xpra.client.window_border import WindowBorder
        border = WindowBorder()
        default_cursor_data = None
        noclient = FakeClient()
        #test with alpha, but not on win32
        #because we can't do alpha on win32 with opengl
        metadata = typedict({"has-alpha" : not WIN32})
        class NoHeaderGLClientWindow(gl_client_window_class):
            def add_header_bar(self):
                """ pretend to add the header bar """
            def schedule_recheck_focus(self):
                """ pretend to handle focus checks """
        window = NoHeaderGLClientWindow(noclient, None, None, 2**32-1, x, y, w, h, w, h,
                                        metadata, False, typedict({}),
                                        border, max_window_size, default_cursor_data, pixel_depth)
        window_backing = window._backing
        window_backing.idle_add = no_idle_add
        window_backing.timeout_add = no_timeout_add
        window_backing.source_remove = no_source_remove
        window.realize()
        window_backing.paint_screen = True
        pixel_format = "BGRX"
        bpp = len(pixel_format)
        options = typedict({"pixel_format" : pixel_format})
        stride = bpp*w
        coding = "rgb32"
        widget = window_backing._backing
        widget.realize()
        def paint_callback(success, message=""):
            log("paint_callback(%s, %s)", success, message)
            draw_result["success"] = success
            if message:
                draw_result["message"] = message.replace("\n", " ")
        log("OpenGL: testing draw on %s widget %s with %s : %s", window, widget, coding, pixel_format)
        pix = AtomicInteger(0x7f)
        REPAINT_DELAY = envint("XPRA_REPAINT_DELAY", int(show)*16)
        gl_icon = get_icon_filename("opengl", ext="png")
        icon_data = None
        if os.path.exists(gl_icon):
            from PIL import Image
            img = Image.open(gl_icon)
            img.load()
            icon_w, icon_h = img.size
            icon_stride = icon_w * 4
            noalpha = Image.new("RGB", img.size, (255, 255, 255))
            noalpha.paste(img, mask=img.split()[3]) # 3 is the alpha channel
            buf = BytesIO()
            try:
                noalpha.save(buf, format="JPEG")
                icon_data = buf.getvalue()
                buf.close()
                icon_format = "jpeg"
            except KeyError as e:
                log("save()", exc_info=True)
                log.warn("OpenGL using png as jpeg is not supported by Pillow: %s", e)
                icon_data = load_binary_file(gl_icon)
                icon_format = "png"
        if not icon_data:
            icon_w = 32
            icon_h = 32
            icon_stride = icon_w * 4
            icon_data = bytes([0])*icon_stride*icon_h
            icon_format = "rgb32"
        def draw():
            v = pix.increase()
            img_data = bytes([v % 256]*stride*h)
            options["flush"] = 1
            window.draw_region(0, 0, w, h, coding, img_data, stride, v, options, [paint_callback])
            options["flush"] = 0
            mx = w//2-icon_w//2
            my = h//2-icon_h//2
            x = round(mx*(1+sin(v/100)))
            y = round(my*(1+cos(v/100)))
            window.draw_region(x, y, icon_w, icon_h, icon_format, icon_data, icon_stride, v, options, [paint_callback])
            return REPAINT_DELAY>0
        #the paint code is actually synchronous here,
        #so we can check the present_fbo() result:
        if show:
            widget.show()
            window.show()
            from gi.repository import Gtk, GLib
            def window_close_event(*_args):
                Gtk.main_quit()
            noclient.window_close_event = window_close_event
            GLib.timeout_add(REPAINT_DELAY, draw)
            Gtk.main()
        else:
            draw()
            #ugly workaround for calling the paint handler
            #when the main loop is not running:
            if hasattr(window_backing, "on_realize"):
                window_backing.on_realize()
        if window_backing.last_present_fbo_error:
            return {
                "success" : False,
                "message" : "failed to present FBO on screen: %s" % window_backing.last_present_fbo_error
                }
    finally:
        if window:
            window.destroy()
    log("test_gl_client_window(..) draw_result=%s", draw_result)
    return draw_result or {"success" : False, "message" : "not painted on screen"}



def main():
    try:
        opengl_props, gl_client_window_module = get_gl_client_window_module(True)
        log("do_run_glcheck() opengl_props=%s, gl_client_window_module=%s", opengl_props, gl_client_window_module)
        gl_client_window_class = gl_client_window_module.GLClientWindow
        pixel_depth = 0
        log("do_run_glcheck() gl_client_window_class=%s, pixel_depth=%s", gl_client_window_class, pixel_depth)
        #if pixel_depth not in (0, 16, 24, 30) and pixel_depth<32:
        #    pixel_depth = 0
        draw_result = test_gl_client_window(gl_client_window_class, pixel_depth=pixel_depth, show=True)
        success = draw_result.pop("success", False)
        opengl_props.update(draw_result)
        if not success:
            opengl_props["safe"] = False
        return 0
    except Exception:
        log("do_run_glcheck(..)", exc_info=True)
        return 1

if __name__ == "__main__":
    r = main()
    sys.exit(r)
