# Copyright 2004-2017 Tom Rothamel <pytom@bishoujo.us>
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation files
# (the "Software"), to deal in the Software without restriction,
# including without limitation the rights to use, copy, modify, merge,
# publish, distribute, sublicense, and/or sell copies of the Software,
# and to permit persons to whom the Software is furnished to do so,
# subject to the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

# This file mediates access to the _renpy module, which is a C module that
# allows us to enhance the feature set of pygame in a renpy specific way.

import pygame_sdl2; pygame_sdl2
import renpy.display
import _renpy

import sys


def convert_and_call(function, src, dst, *args):
    """
    This calls the function with the source and destination
    surface. The surfaces must have the same alpha.

    If the surfaces are not 24 or 32 bits per pixel, or don't have the
    same format, they are converted and then converted back.
    """

    # Now that all surfaces are 32bpp, this function doesn't do much
    # of anything anymore.

    if (dst.get_masks()[3] != 0) != (src.get_masks()[3] != 0):
        raise Exception("Surface alphas do not match.")

    function(src, dst, *args)


def pixellate(src, dst, avgwidth, avgheight, outwidth, outheight):
    """
    This pixellates the source surface. First, every pixel in the
    source surface is projected onto a virtual surface, such that
    the average value of every avgwidth x avgheight pixels becomes
    one virtual pixel. It then gets projected back onto the
    destination surface at a ratio of one virtual pixel to every
    outwidth x outheight destination pixels.

    If either src or dst is not a 24 or 32 bit surface, they are
    converted... but that may be a significant performance hit.

    The two surfaces must either have the same alpha or no alpha.
    """

    convert_and_call(_renpy.pixellate,
                     src, dst,
                     avgwidth, avgheight,
                     outwidth, outheight)


def scale(s, size):
    """
    Scales down the supplied pygame surface by the given X and Y
    factors.

    Always works, but may not be high quality.
    """

    d = renpy.display.pgrender.surface(size, True)

    bilinear_scale(s, d)

    return d


# What we have here are a pair of tables mapping masks to byte offsets
# for 24 and 32 bpp modes. We represent 0xff000000 as positive and negative
# numbers so that it doesn't yield a warning, and so that it works on
# 32 and 64 bit platforms.
if sys.byteorder == 'big':
    bo32 = { 255 : 3, 65280 : 2, 16711680 : 1, 4278190080 : 0, -16777216 : 0, }
else:
    bo32 = { 255 : 0, 65280 : 1, 16711680 : 2, 4278190080 : 3, -16777216 : 3, }

bo_cache = None


def byte_offset(src):
    """
    Given the surface src, returns a 4-tuple giving the byte offsets
    for the red, green, blue, and alpha components of the pixels in
    the surface. If a component doesn't exist, None is returned.
    """

    global bo_cache

    if bo_cache is None:
        bo_cache = [ bo32[i] for i in src.get_masks() ]

    return bo_cache


def endian_order(src, r, g, b, a):

    if bo_cache is None:
        byte_offset(src)

    rv = [ a, a, a, a ]

    for i, index_i in zip((r, g, b, a), bo_cache):
        rv[index_i] = i

    return rv


def linmap(src, dst, rmap, gmap, bmap, amap):
    """
    This maps the colors between two surfaces. The various map
    parameters should be fixed-point integers, with 1.0 == 256.
    """

    convert_and_call(_renpy.linmap,
                     src, dst,
                     *endian_order(dst, rmap, gmap, bmap, amap))


save_png = _renpy.save_png


def map(src, dst, rmap, gmap, bmap, amap):  # @ReservedAssignment
    """
    This maps the colors between two surfaces. The various map
    parameters must be 256 character long strings, with the value
    of a character at a given offset being what a particular pixel
    component value is mapped to.
    """

    convert_and_call(_renpy.map,
                     src, dst,
                     *endian_order(dst, rmap, gmap, bmap, amap))


def twomap(src, dst, white, black):
    """
    Given colors for white and black, linearly maps things
    appropriately, taking the alpha channel from white.
    """

    wr = white[0]
    wg = white[1]
    wb = white[2]
    wa = white[3]

    br = black[0]
    bg = black[1]
    bb = black[2]

    ramp = renpy.display.im.ramp

    if br == 0 and bg == 0 and bb == 0:
        linmap(src, dst,
               wr + 1,
               wg + 1,
               wb + 1,
               wa + 1)
    else:
        map(src, dst,
            ramp(br, wr),
            ramp(bg, wg),
            ramp(bb, wb),
            ramp(0, wa))


def alpha_munge(src, dst, amap):
    """
    This samples the red channel from src, maps it through amap, and
    place it into the alpha channel of amap.
    """

    if src.get_size() != dst.get_size():
        return

    red = byte_offset(src)[0]
    alpha = byte_offset(dst)[3]

    if red is not None and alpha is not None:
        _renpy.alpha_munge(src, dst, red, alpha, amap)


def bilinear_scale(src, dst, sx=0, sy=0, sw=None, sh=None, dx=0, dy=0, dw=None, dh=None, precise=0):

    if sw is None:
        sw, sh = src.get_size()
    if dw is None:
        dw, dh = dst.get_size()

    while True:

        if sw <= dw * 2 and sh <= dh * 2:
            break

        nsw = max(sw / 2, dw)
        nsh = max(sh / 2, dh)

        nsrc = renpy.display.pgrender.surface((nsw, nsh), src.get_masks()[3])

        _renpy.bilinear(src, nsrc, sx, sy, sw, sh, precise=precise)

        sx = 0
        sy = 0
        sw = nsw
        sh = nsh
        src = nsrc

    _renpy.bilinear(src, dst, sx, sy, sw, sh, dx, dy, dw, dh, precise=precise)


transform = _renpy.transform

# Note: Blend requires all surfaces to be the same size.
blend = _renpy.blend


def imageblend(a, b, dst, img, amap):
    alpha = byte_offset(img)[3]
    _renpy.imageblend(a, b, dst, img, alpha, amap)


def colormatrix(src, dst, matrix):
    c = [ matrix[0:5], matrix[5:10], matrix[10:15], matrix[15:20] ]
    offs = byte_offset(src)

    o = [ None ] * 4
    for i in range(0, 4):
        o[offs[i]] = i

    _renpy.colormatrix(src, dst,
                       c[o[0]][o[0]], c[o[0]][o[1]], c[o[0]][o[2]], c[o[0]][o[3]], c[o[0]][4],
                       c[o[1]][o[0]], c[o[1]][o[1]], c[o[1]][o[2]], c[o[1]][o[3]], c[o[1]][4],
                       c[o[2]][o[0]], c[o[2]][o[1]], c[o[2]][o[2]], c[o[2]][o[3]], c[o[2]][4],
                       c[o[3]][o[0]], c[o[3]][o[1]], c[o[3]][o[2]], c[o[3]][o[3]], c[o[3]][4])


def subpixel(src, dst, x, y):

    shift = src.get_shifts()[3]
    _renpy.subpixel(src, dst, x, y, shift)
