# -*- coding: utf-8 -*-
#
# gPodder - A media aggregator and podcast client
# Copyright (c) 2005-2018 The gPodder Team
#
# gPodder 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.
#
# gPodder 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 this program.  If not, see <http://www.gnu.org/licenses/>.
#


#
#  draw.py -- Draw routines for gPodder-specific graphics
#  Thomas Perl <thp@perli.net>, 2007-11-25
#

import io
import math

import cairo
import gi
from gi.repository import Gdk, GdkPixbuf, Gtk, Pango, PangoCairo

import gpodder

gi.require_version('PangoCairo', '1.0')





class TextExtents(object):
    def __init__(self, ctx, text):
        tuple = ctx.text_extents(text)
        (self.x_bearing, self.y_bearing, self.width, self.height, self.x_advance, self.y_advance) = tuple


EPISODE_LIST_ICON_SIZE = 16

RRECT_LEFT_SIDE = 1
RRECT_RIGHT_SIDE = 2


def draw_rounded_rectangle(ctx, x, y, w, h, r=10, left_side_width=None,
                           sides_to_draw=0, close=False):
    assert left_side_width is not None

    x = int(x)
    offset = 0
    if close: offset = 0.5

    if sides_to_draw & RRECT_LEFT_SIDE:
        ctx.move_to(x + int(left_side_width) - offset, y + h)
        ctx.line_to(x + r, y + h)
        ctx.curve_to(x, y + h, x, y + h, x, y + h - r)
        ctx.line_to(x, y + r)
        ctx.curve_to(x, y, x, y, x + r, y)
        ctx.line_to(x + int(left_side_width) - offset, y)
        if close:
            ctx.line_to(x + int(left_side_width) - offset, y + h)

    if sides_to_draw & RRECT_RIGHT_SIDE:
        ctx.move_to(x + int(left_side_width) + offset, y)
        ctx.line_to(x + w - r, y)
        ctx.curve_to(x + w, y, x + w, y, x + w, y + r)
        ctx.line_to(x + w, y + h - r)
        ctx.curve_to(x + w, y + h, x + w, y + h, x + w - r, y + h)
        ctx.line_to(x + int(left_side_width) + offset, y + h)
        if close:
            ctx.line_to(x + int(left_side_width) + offset, y)


def rounded_rectangle(ctx, x, y, width, height, radius=4.):
    """Simple rounded rectangle algorithmn

    http://www.cairographics.org/samples/rounded_rectangle/
    """
    degrees = math.pi / 180.
    ctx.new_sub_path()
    if width > radius:
        ctx.arc(x + width - radius, y + radius, radius, -90. * degrees, 0)
        ctx.arc(x + width - radius, y + height - radius, radius, 0, 90. * degrees)
        ctx.arc(x + radius, y + height - radius, radius, 90. * degrees, 180. * degrees)
        ctx.arc(x + radius, y + radius, radius, 180. * degrees, 270. * degrees)
    ctx.close_path()


def draw_text_box_centered(ctx, widget, w_width, w_height, text, font_desc=None, add_progress=None):
    style_context = widget.get_style_context()
    text_color = style_context.get_color(Gtk.StateFlags.PRELIGHT)

    if font_desc is None:
        font_desc = style_context.get_font(Gtk.StateFlags.NORMAL)
        font_desc.set_size(14 * Pango.SCALE)

    pango_context = widget.create_pango_context()
    layout = Pango.Layout(pango_context)
    layout.set_font_description(font_desc)
    layout.set_text(text, -1)
    width, height = layout.get_pixel_size()

    ctx.move_to(w_width / 2 - width / 2, w_height / 2 - height / 2)
    ctx.set_source_rgba(text_color.red, text_color.green, text_color.blue, 0.5)
    PangoCairo.show_layout(ctx, layout)

    # Draw an optional progress bar below the text (same width)
    if add_progress is not None:
        bar_height = 10
        ctx.set_source_rgba(*text_color)
        ctx.set_line_width(1.)
        rounded_rectangle(ctx,
                          w_width / 2 - width / 2 - .5,
                          w_height / 2 + height - .5, width + 1, bar_height + 1)
        ctx.stroke()
        rounded_rectangle(ctx,
                          w_width / 2 - width / 2,
                          w_height / 2 + height, int(width * add_progress) + .5, bar_height)
        ctx.fill()


def draw_cake(percentage, text=None, emblem=None, size=None):
    # Download percentage bar icon - it turns out the cake is a lie (d'oh!)
    # ..but the inital idea was to have a cake-style indicator, but that
    # didn't work as well as the progress bar, but the name stuck..

    if size is None:
        size = EPISODE_LIST_ICON_SIZE

    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, size, size)
    ctx = cairo.Context(surface)

    bgc = get_background_color(Gtk.StateFlags.ACTIVE)
    fgc = get_background_color(Gtk.StateFlags.SELECTED)
    txc = get_foreground_color(Gtk.StateFlags.NORMAL)

    border = 1.5
    height = int(size * .4)
    width = size - 2 * border
    y = (size - height) / 2 + .5
    x = border

    # Background
    ctx.rectangle(x, y, width, height)
    ctx.set_source_rgb(bgc.red, bgc.green, bgc.blue)
    ctx.fill()

    # Filling
    if percentage > 0:
        fill_width = max(1, min(width - 2, (width - 2) * percentage + .5))
        ctx.rectangle(x + 1, y + 1, fill_width, height - 2)
        ctx.set_source_rgb(0.289, 0.5625, 0.84765625)
        ctx.fill()

    # Border
    ctx.rectangle(x, y, width, height)
    ctx.set_source_rgb(txc.red, txc.green, txc.blue)
    ctx.set_line_width(1)
    ctx.stroke()

    del ctx
    return surface


def draw_text_pill(left_text, right_text, x=0, y=0, border=2, radius=14, font_desc=None):

    # Use GTK+ style of a normal Button
    widget = Gtk.Label()
    style_context = widget.get_style_context()

    # Padding (in px) at the right edge of the image (for Ubuntu; bug 1533)
    padding_right = 7

    x_border = border * 2

    if font_desc is None:
        font_desc = style_context.get_font(Gtk.StateFlags.NORMAL)
        font_desc.set_weight(Pango.Weight.BOLD)

    pango_context = widget.create_pango_context()
    layout_left = Pango.Layout(pango_context)
    layout_left.set_font_description(font_desc)
    layout_left.set_text(left_text, -1)
    layout_right = Pango.Layout(pango_context)
    layout_right.set_font_description(font_desc)
    layout_right.set_text(right_text, -1)

    width_left, height_left = layout_left.get_pixel_size()
    width_right, height_right = layout_right.get_pixel_size()

    text_height = max(height_left, height_right)

    image_height = int(y + text_height + border * 2)
    image_width = int(x + width_left + width_right + x_border * 4 + padding_right)

    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, image_width, image_height)
    ctx = cairo.Context(surface)

    # Clip so as to not draw on the right padding (for Ubuntu; bug 1533)
    ctx.rectangle(0, 0, image_width - padding_right, image_height)
    ctx.clip()

    if left_text == '0':
        left_text = None
    if right_text == '0':
        right_text = None

    left_side_width = width_left + x_border * 2
    right_side_width = width_right + x_border * 2

    rect_width = left_side_width + right_side_width
    rect_height = text_height + border * 2
    if left_text is not None:
        draw_rounded_rectangle(ctx, x, y, rect_width, rect_height, radius,
                               left_side_width, RRECT_LEFT_SIDE, right_text is None)
        linear = cairo.LinearGradient(x, y, x + left_side_width / 2, y + rect_height / 2)
        linear.add_color_stop_rgba(0, .8, .8, .8, .5)
        linear.add_color_stop_rgba(.4, .8, .8, .8, .7)
        linear.add_color_stop_rgba(.6, .8, .8, .8, .6)
        linear.add_color_stop_rgba(.9, .8, .8, .8, .8)
        linear.add_color_stop_rgba(1, .8, .8, .8, .9)
        ctx.set_source(linear)
        ctx.fill()
        xpos, ypos, width_left, height = x + 1, y + 1, left_side_width, rect_height - 2
        if right_text is None:
            width_left -= 2
        draw_rounded_rectangle(ctx, xpos, ypos, rect_width, height, radius, width_left, RRECT_LEFT_SIDE, right_text is None)
        ctx.set_source_rgba(1., 1., 1., .3)
        ctx.set_line_width(1)
        ctx.stroke()
        draw_rounded_rectangle(ctx, x, y, rect_width, rect_height, radius,
                               left_side_width, RRECT_LEFT_SIDE, right_text is None)
        ctx.set_source_rgba(.2, .2, .2, .6)
        ctx.set_line_width(1)
        ctx.stroke()

        ctx.move_to(x + x_border, y + 1 + border)
        ctx.set_source_rgba(0, 0, 0, 1)
        PangoCairo.show_layout(ctx, layout_left)
        ctx.move_to(x - 1 + x_border, y + border)
        ctx.set_source_rgba(1, 1, 1, 1)
        PangoCairo.show_layout(ctx, layout_left)

    if right_text is not None:
        draw_rounded_rectangle(ctx, x, y, rect_width, rect_height, radius, left_side_width, RRECT_RIGHT_SIDE, left_text is None)
        linear = cairo.LinearGradient(
            x + left_side_width,
            y,
            x + left_side_width + right_side_width / 2,
            y + rect_height)
        linear.add_color_stop_rgba(0, .2, .2, .2, .9)
        linear.add_color_stop_rgba(.4, .2, .2, .2, .8)
        linear.add_color_stop_rgba(.6, .2, .2, .2, .6)
        linear.add_color_stop_rgba(.9, .2, .2, .2, .7)
        linear.add_color_stop_rgba(1, .2, .2, .2, .5)
        ctx.set_source(linear)
        ctx.fill()
        xpos, ypos, width, height = x, y + 1, rect_width - 1, rect_height - 2
        if left_text is None:
            xpos, width = x + 1, rect_width - 2
        draw_rounded_rectangle(ctx, xpos, ypos, width, height, radius, left_side_width, RRECT_RIGHT_SIDE, left_text is None)
        ctx.set_source_rgba(1., 1., 1., .3)
        ctx.set_line_width(1)
        ctx.stroke()
        draw_rounded_rectangle(ctx, x, y, rect_width, rect_height, radius, left_side_width, RRECT_RIGHT_SIDE, left_text is None)
        ctx.set_source_rgba(.1, .1, .1, .6)
        ctx.set_line_width(1)
        ctx.stroke()

        ctx.move_to(x + left_side_width + x_border, y + 1 + border)
        ctx.set_source_rgba(0, 0, 0, 1)
        PangoCairo.show_layout(ctx, layout_right)
        ctx.move_to(x - 1 + left_side_width + x_border, y + border)
        ctx.set_source_rgba(1, 1, 1, 1)
        PangoCairo.show_layout(ctx, layout_right)

    return surface


def draw_cake_pixbuf(percentage, text=None, emblem=None):
    return cairo_surface_to_pixbuf(draw_cake(percentage, text, emblem))


def draw_pill_pixbuf(left_text, right_text):
    return cairo_surface_to_pixbuf(draw_text_pill(left_text, right_text))


def cairo_surface_to_pixbuf(s):
    """
    Converts a Cairo surface to a Gtk Pixbuf by
    encoding it as PNG and using the PixbufLoader.
    """
    bio = io.BytesIO()
    try:
        s.write_to_png(bio)
    except:
        # Write an empty PNG file to the StringIO, so
        # in case of an error we have "something" to
        # load. This happens in PyCairo < 1.1.6, see:
        # http://webcvs.cairographics.org/pycairo/NEWS?view=markup
        # Thanks to Chris Arnold for reporting this bug
        bio.write('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAAZiS0dEAP8A\n/wD/oL2nkwAAAAlwSFlzAAALEwAACxMBAJqcGAAAAAd0SU1FB9cMEQkqIyxn3RkAAAAZdEVYdENv\nbW1lbnQAQ3JlYXRlZCB3aXRoIEdJTVBXgQ4XAAAADUlEQVQI12NgYGBgAAAABQABXvMqOgAAAABJ\nRU5ErkJggg==\n'.decode('base64'))

    pbl = GdkPixbuf.PixbufLoader()
    pbl.write(bio.getvalue())
    pbl.close()

    pixbuf = pbl.get_pixbuf()
    return pixbuf


def progressbar_pixbuf(width, height, percentage):
    COLOR_BG = (.4, .4, .4, .4)
    COLOR_FG = (.2, .9, .2, 1.)
    COLOR_FG_HIGH = (1., 1., 1., .5)
    COLOR_BORDER = (0., 0., 0., 1.)

    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
    ctx = cairo.Context(surface)

    padding = int(width / 8.0)
    bar_width = 2 * padding
    bar_height = height - 2 * padding
    bar_height_fill = bar_height * percentage

    # Background
    ctx.rectangle(padding, padding, bar_width, bar_height)
    ctx.set_source_rgba(*COLOR_BG)
    ctx.fill()

    # Foreground
    ctx.rectangle(padding, padding + bar_height - bar_height_fill, bar_width, bar_height_fill)
    ctx.set_source_rgba(*COLOR_FG)
    ctx.fill()
    ctx.rectangle(padding + bar_width / 3,
                  padding + bar_height - bar_height_fill,
                  bar_width / 4,
                  bar_height_fill)
    ctx.set_source_rgba(*COLOR_FG_HIGH)
    ctx.fill()

    # Border
    ctx.rectangle(padding - .5, padding - .5, bar_width + 1, bar_height + 1)
    ctx.set_source_rgba(* COLOR_BORDER)
    ctx.set_line_width(1.)
    ctx.stroke()

    return cairo_surface_to_pixbuf(surface)


def get_background_color(state=Gtk.StateFlags.NORMAL, widget=Gtk.TreeView()):
    """
    @param state state flag (e.g. Gtk.StateFlags.SELECTED to get selected background)
    @param widget specific widget to get info from.
           defaults to TreeView which has all one usually wants.
    @return background color from theme for widget or from its parents if transparent.
    """
    p = widget
    color = Gdk.RGBA(0, 0, 0, 0)
    while p is not None and color.alpha == 0:
        style_context = p.get_style_context()
        color = style_context.get_background_color(0)
        p = p.get_parent()
    return color


def get_foreground_color(state=Gtk.StateFlags.NORMAL, widget=Gtk.TreeView()):
    """
    @param state state flag (e.g. Gtk.StateFlags.SELECTED to get selected text color)
    @param widget specific widget to get info from
           defaults to TreeView which has all one usually wants.
    @return text color from theme for widget or its parents if transparent
    """
    p = widget
    color = Gdk.RGBA(0, 0, 0, 0)
    style_context = widget.get_style_context()
    foreground = style_context.get_color(0)
    while p is not None and color.alpha == 0:
        style_context = p.get_style_context()
        color = style_context.get_color(0)
        p = p.get_parent()
    return color