/*
 * Copyright © 2009 Intel Corporation
 *
 * 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 (including the next
 * paragraph) 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.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *
 */


/** @file glamor_putaimge.c
 *
 * XPutImage implementation
 */
#include "glamor_priv.h"

void
glamor_init_putimage_shaders(ScreenPtr screen)
{
#if 0
    glamor_screen_private *glamor_priv = glamor_get_screen_private(screen);
    const char *xybitmap_vs =
	"uniform float x_bias;\n"
	"uniform float x_scale;\n"
	"uniform float y_bias;\n"
	"uniform float y_scale;\n"
	"varying vec2 bitmap_coords;\n"
	"void main()\n"
	"{\n"
	"	gl_Position = vec4((gl_Vertex.x + x_bias) * x_scale,\n"
	"			   (gl_Vertex.y + y_bias) * y_scale,\n"
	"			   0,\n"
	"			   1);\n"
	"	bitmap_coords = gl_MultiTexCoord0.xy;\n"
	"}\n";
    const char *xybitmap_fs =
	"uniform vec4 fg, bg;\n"
	"varying vec2 bitmap_coords;\n"
	"uniform sampler2D bitmap_sampler;\n"
	"void main()\n"
	"{\n"
	"	float bitmap_value = texture2D(bitmap_sampler,\n"
	"				       bitmap_coords).x;\n"
	"	gl_FragColor = mix(bg, fg, bitmap_value);\n"
	"}\n";
    GLint fs_prog, vs_prog, prog;
    GLint sampler_uniform_location;

    if (!GLEW_ARB_fragment_shader)
	return;

    prog = dispatch->glCreateProgram();
    vs_prog = glamor_compile_glsl_prog(GL_VERTEX_SHADER, xybitmap_vs);
    fs_prog = glamor_compile_glsl_prog(GL_FRAGMENT_SHADER, xybitmap_fs);
    dispatch->glAttachShader(prog, vs_prog);
    dispatch->glAttachShader(prog, fs_prog);
    glamor_link_glsl_prog(prog);

    dispatch->glUseProgram(prog);
    sampler_uniform_location = dispatch->glGetUniformLocation(prog, "bitmap_sampler");
    dispatch->glUniform1i(sampler_uniform_location, 0);

    glamor_priv->put_image_xybitmap_fg_uniform_location =
	dispatch->glGetUniformLocation(prog, "fg");
    glamor_priv->put_image_xybitmap_bg_uniform_location =
	dispatch->glGetUniformLocation(prog, "bg");
    glamor_get_transform_uniform_locations(prog,
					   &glamor_priv->put_image_xybitmap_transform);
    glamor_priv->put_image_xybitmap_prog = prog;
    dispatch->glUseProgram(0);
#endif
}


/* Do an XYBitmap putimage.  The bits are byte-aligned rows of bitmap
 * data (where each row starts at a bit index of left_pad), and the
 * destination gets filled with the gc's fg color where the bitmap is set
 * and the bg color where the bitmap is unset.
 *
 * Implement this by passing the bitmap right through to GL, and sampling
 * it to choose between fg and bg in the fragment shader.  The driver may
 * be exploding the bitmap up to be an 8-bit alpha texture, in which
 * case we might be better off just doing the fg/bg choosing in the CPU
 * and just draw the resulting texture to the destination.
 */
#if 0

static int
y_flip(PixmapPtr pixmap, int y)
{
    ScreenPtr screen = pixmap->drawable.pScreen;
    PixmapPtr screen_pixmap = screen->GetScreenPixmap(screen);

    if (pixmap == screen_pixmap)
	return (pixmap->drawable.height - 1) - y;
    else
	return y;
}


static void
glamor_put_image_xybitmap(DrawablePtr drawable, GCPtr gc,
			  int x, int y, int w, int h, int left_pad,
			  int image_format, char *bits)
{
    ScreenPtr screen = drawable->pScreen;
    PixmapPtr pixmap = glamor_get_drawable_pixmap(drawable);
    glamor_screen_private *glamor_priv = glamor_get_screen_private(screen);
    float fg[4], bg[4];
    GLuint tex;
    unsigned int stride = PixmapBytePad(1, w + left_pad);
    RegionPtr clip;
    BoxPtr box;
    int nbox;
    float dest_coords[8];
    const float bitmap_coords[8] = {
	0.0, 0.0,
	1.0, 0.0,
	1.0, 1.0,
	0.0, 1.0,
    };
    GLfloat xscale, yscale;
    glamor_pixmap_private *pixmap_priv;
   
    pixmap_priv = glamor_get_pixmap_private(pixmap);

    pixmap_priv_get_scale(pixmap_priv, &xscale, &yscale);

    glamor_set_normalize_vcoords(xscale, yscale,
				 x, y,
				 x + w, y + h,
				 glamor_priv->yInverted,
				 dest_coords);

    glamor_fallback("glamor_put_image_xybitmap: disabled\n");
    goto fail;

    if (glamor_priv->put_image_xybitmap_prog == 0) {
	ErrorF("no program for xybitmap putimage\n");
	goto fail;
    }

    glamor_set_alu(gc->alu);
    if (!glamor_set_planemask(pixmap, gc->planemask))
	goto fail;

    dispatch->glUseProgram(glamor_priv->put_image_xybitmap_prog);

    glamor_get_color_4f_from_pixel(pixmap, gc->fgPixel, fg);
    dispatch->glUniform4fv(glamor_priv->put_image_xybitmap_fg_uniform_location,
		    1, fg);
    glamor_get_color_4f_from_pixel(pixmap, gc->bgPixel, bg);
    dispatch->glUniform4fv(glamor_priv->put_image_xybitmap_bg_uniform_location,
		    1, bg);

    dispatch->glGenTextures(1, &tex);
    dispatch->glActiveTexture(GL_TEXTURE0);
    dispatch->glEnable(GL_TEXTURE_2D);
    dispatch->glBindTexture(GL_TEXTURE_2D, tex);
    dispatch->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    dispatch->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    dispatch->glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    dispatch->glPixelStorei(GL_UNPACK_ROW_LENGTH, stride * 8);
    dispatch->glPixelStorei(GL_UNPACK_SKIP_PIXELS, left_pad);
    dispatch->glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA,
		 w, h, 0,
		 GL_COLOR_INDEX, GL_BITMAP, bits);
    dispatch->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
    dispatch->glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);
    dispatch->glEnable(GL_TEXTURE_2D);

    /* Now that we've set up our bitmap texture and the shader, shove
     * the destination rectangle through the cliprects and run the
     * shader on the resulting fragments.
     */
    dispatch->glVertexPointer(2, GL_FLOAT, 0, dest_coords);
    dispatch->glEnableClientState(GL_VERTEX_ARRAY);
    dispatch->glClientActiveTexture(GL_TEXTURE0);
    dispatch->glTexCoordPointer(2, GL_FLOAT, 0, bitmap_coords);
    dispatch->glEnableClientState(GL_TEXTURE_COORD_ARRAY);

    dispatch->glEnable(GL_SCISSOR_TEST);
    clip = fbGetCompositeClip(gc);
    for (nbox = REGION_NUM_RECTS(clip),
	 box = REGION_RECTS(clip);
	 nbox--;
	 box++)
    {
	int x1 = x;
	int y1 = y;
	int x2 = x + w;
	int y2 = y + h;

	if (x1 < box->x1)
	    x1 = box->x1;
	if (y1 < box->y1)
	    y1 = box->y1;
	if (x2 > box->x2)
	    x2 = box->x2;
	if (y2 > box->y2)
	    y2 = box->y2;
	if (x1 >= x2 || y1 >= y2)
	    continue;

	dispatch->glScissor(box->x1,
		  y_flip(pixmap, box->y1),
		  box->x2 - box->x1,
		  box->y2 - box->y1);
	dispatch->glDrawArrays(GL_QUADS, 0, 4);
    }

    dispatch->glDisable(GL_SCISSOR_TEST);
    glamor_set_alu(GXcopy);
    glamor_set_planemask(pixmap, ~0);
    dispatch->glDeleteTextures(1, &tex);
    dispatch->glDisable(GL_TEXTURE_2D);
    dispatch->glDisableClientState(GL_VERTEX_ARRAY);
    dispatch->glDisableClientState(GL_TEXTURE_COORD_ARRAY);
    return;
    glamor_set_alu(GXcopy);
    glamor_set_planemask(pixmap, ~0);
    glamor_fallback(": to %p (%c)\n",
		    drawable, glamor_get_drawable_location(drawable));
fail:
    if (glamor_prepare_access(drawable, GLAMOR_ACCESS_RW)) {
	fbPutImage(drawable, gc, 1, x, y, w, h, left_pad, XYBitmap, bits);
	glamor_finish_access(drawable);
    }
}
#endif


void
glamor_put_image(DrawablePtr drawable, GCPtr gc, int depth, int x, int y,
		 int w, int h, int left_pad, int image_format, char *bits)
{
    glamor_screen_private *glamor_priv =
	glamor_get_screen_private(drawable->pScreen);
    glamor_gl_dispatch *dispatch = &glamor_priv->dispatch;
    PixmapPtr pixmap = glamor_get_drawable_pixmap(drawable);
    glamor_pixmap_private *pixmap_priv = glamor_get_pixmap_private(pixmap);
    GLenum type, format, iformat;
    RegionPtr clip;
    BoxPtr pbox;
    int nbox;
    int src_stride = PixmapBytePad(w, drawable->depth);
    int x_off, y_off;
    float vertices[8], texcoords[8];
    GLfloat xscale, yscale, txscale, tyscale;
    GLuint tex;
    int no_alpha, no_revert;
    if (image_format == XYBitmap) {
	assert(depth == 1);
        goto fail;
	return;
    }

    if (!GLAMOR_PIXMAP_PRIV_HAS_FBO(pixmap_priv)) {
	glamor_fallback("has no fbo.\n");
        goto fail;
    }

    if (image_format != ZPixmap) {
	glamor_fallback("non-ZPixmap\n");
	goto fail;
    }

    if (!glamor_set_planemask(pixmap, gc->planemask)) {
	goto fail;
    }
    glamor_set_alu(dispatch, gc->alu);

    if (glamor_get_tex_format_type_from_pixmap(pixmap,
                                               &format, 
                                               &type, 
                                               &no_alpha,
                                               &no_revert
                                               )) {
      glamor_fallback("unknown depth. %d \n", 
                     drawable->depth);
      goto fail;
    }

    /* XXX consider to reuse a function to do the following work. */
    glamor_set_destination_pixmap_priv_nc(pixmap_priv);
    glamor_validate_pixmap(pixmap);
    dispatch->glVertexAttribPointer(GLAMOR_VERTEX_POS, 2, GL_FLOAT, GL_FALSE,
                        2 * sizeof(float),
                        vertices);
    dispatch->glEnableVertexAttribArray(GLAMOR_VERTEX_POS);
    
    dispatch->glVertexAttribPointer(GLAMOR_VERTEX_SOURCE, 2, GL_FLOAT, GL_FALSE,
                        2 * sizeof(float),
                        texcoords);
    dispatch->glEnableVertexAttribArray(GLAMOR_VERTEX_SOURCE);

    if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP) {
      dispatch->glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
      dispatch->glPixelStorei(GL_UNPACK_ROW_LENGTH, src_stride * 8 /
  		    pixmap->drawable.bitsPerPixel);
    }
    else {
      dispatch->glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
//      dispatch->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
    }
    
    dispatch->glGenTextures(1, &tex);
    dispatch->glActiveTexture(GL_TEXTURE0);
    dispatch->glBindTexture(GL_TEXTURE_2D, tex);
    if (glamor_priv->gl_flavor == GLAMOR_GL_ES2) {
      iformat = format;
    } 
    else {
      iformat = GL_RGBA;
    }

    dispatch->glTexImage2D(GL_TEXTURE_2D, 0, iformat,
		 w, h, 0,
		 format, type, bits);

    dispatch->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    dispatch->glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
#ifndef GLAMOR_GLES2
    dispatch->glEnable(GL_TEXTURE_2D);
#endif

    dispatch->glUseProgram(glamor_priv->finish_access_prog[no_alpha]);
    dispatch->glUniform1i(glamor_priv->finish_access_no_revert[no_alpha], no_revert);
      dispatch->glUniform1i(glamor_priv->finish_access_swap_rb[no_alpha], 0);

    x += drawable->x;
    y += drawable->y;

    glamor_get_drawable_deltas(drawable, pixmap, &x_off, &y_off);
    clip = fbGetCompositeClip(gc);

    txscale = 1.0/w;
    tyscale = 1.0/h;
    pixmap_priv_get_scale(pixmap_priv, &xscale, &yscale);

    for (nbox = REGION_NUM_RECTS(clip),
	 pbox = REGION_RECTS(clip);
	 nbox--;
	 pbox++)
    {
	int x1 = x;
	int y1 = y;
	int x2 = x + w;
	int y2 = y + h;

	if (x1 < pbox->x1)
	    x1 = pbox->x1;
	if (y1 < pbox->y1)
	    y1 = pbox->y1;
	if (x2 > pbox->x2)
	    x2 = pbox->x2;
	if (y2 > pbox->y2)
	    y2 = pbox->y2;
	if (x1 >= x2 || y1 >= y2)
	    continue;

	glamor_set_normalize_tcoords( txscale, tyscale, 
				      x1 - x, y1 - y,
				      x2 - x, y2 - y,
				      1,
				      texcoords);

	glamor_set_normalize_vcoords( xscale, yscale,
				      x1 + x_off, y1 + y_off,
				      x2 + x_off, y2 + y_off,
				      glamor_priv->yInverted,
				      vertices);

	dispatch->glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
    }

#ifndef GLAMOR_GLES2
    dispatch->glDisable(GL_TEXTURE_2D);
#endif
    dispatch->glUseProgram(0);
    dispatch->glDisableVertexAttribArray(GLAMOR_VERTEX_POS);
    dispatch->glDisableVertexAttribArray(GLAMOR_VERTEX_SOURCE);
    dispatch->glDeleteTextures(1, &tex);
    if (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP)
      dispatch->glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
    glamor_set_alu(dispatch, GXcopy);
    glamor_set_planemask(pixmap, ~0);
    return;

fail:
    glamor_set_planemask(pixmap, ~0);
    glamor_fallback("to %p (%c)\n",
		    drawable, glamor_get_drawable_location(drawable));
    if (glamor_prepare_access(&pixmap->drawable, GLAMOR_ACCESS_RW)) {
	fbPutImage(&pixmap->drawable, gc, depth, x, y, w, h, left_pad, image_format,
		   bits);
	glamor_finish_access(&pixmap->drawable);
    }
}