/*
 * Copyright (c) 2013 VMware, Inc.
 *
 * 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
 * on the rights to use, copy, modify, merge, publish, distribute, sub
 * license, 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
 * NON-INFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS AND/OR THEIR
 * SUPPLIERS 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:
 *    Roland Scheidegger <sroland@vmware.com>
 *
 * Based on arb_shader_texture_lod-texgrad:
 *    Marek Olšák <maraeo@gmail.com>
 */

#include "piglit-util-gl.h"

PIGLIT_GL_TEST_CONFIG_BEGIN

	config.supports_gl_compat_version = 10;

	config.window_width = 512;
	config.window_height = 256;
	config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
	config.khr_no_error_support = PIGLIT_NO_ERRORS;

PIGLIT_GL_TEST_CONFIG_END

#define TEX_WIDTH 256
#define TEX_HEIGHT 256

static const float colors[][3] = {
	{1.0, 0.0, 0.0},
	{0.0, 1.0, 0.0},
	{0.0, 0.0, 1.0},
	{1.0, 1.0, 0.0},
	{0.0, 1.0, 1.0},
	{1.0, 0.0, 1.0},
	{0.5, 0.0, 0.5},
	{1.0, 1.0, 1.0},
};

static const char *sh_tex =
	"uniform samplerCube tex;"
	"void main()"
	"{"
	"   gl_FragColor = textureCube(tex, gl_TexCoord[0].xyz);"
	"}";

static const char *sh_texgrad =
	"#extension GL_ARB_shader_texture_lod : enable\n"
	"uniform samplerCube tex;"
	"void main()"
	"{"
	"   gl_FragColor = textureCubeGradARB(tex, gl_TexCoord[0].xyz,"
	"                                     dFdx(gl_TexCoord[0].xyz),"
	"                                     dFdy(gl_TexCoord[0].xyz));"
	"}";

static GLint prog_tex, prog_texgrad;

void piglit_init(int argc, char **argv)
{
	GLuint tex, fb;
	GLenum status;
	int i, j, dim;

	piglit_require_fragment_shader();
	piglit_require_extension("GL_EXT_framebuffer_object");
	piglit_require_extension("GL_ARB_shader_texture_lod");

	prog_tex = piglit_build_simple_program(NULL, sh_tex);
	prog_texgrad = piglit_build_simple_program(NULL, sh_texgrad);

	glGenTextures(1, &tex);
	glBindTexture(GL_TEXTURE_CUBE_MAP, tex);

	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

	for (j = GL_TEXTURE_CUBE_MAP_POSITIVE_X; j <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z; j++) {
		for (i = 0, dim = TEX_WIDTH; dim >0; i++, dim /= 2) {
			glTexImage2D(j, i, GL_RGBA,
				     dim, dim,
				     0,
				     GL_RGBA, GL_UNSIGNED_BYTE, NULL);
		}
	}
	if (!piglit_check_gl_error(GL_NO_ERROR))
		piglit_report_result(PIGLIT_FAIL);

	glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
	glDisable(GL_TEXTURE_CUBE_MAP);

	glGenFramebuffersEXT(1, &fb);
	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb);

	for (j = GL_TEXTURE_CUBE_MAP_POSITIVE_X; j <= GL_TEXTURE_CUBE_MAP_NEGATIVE_Z; j++) {
		for (i = 0, dim = TEX_WIDTH; dim >0; i++, dim /= 2) {
			glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT,
						  GL_COLOR_ATTACHMENT0_EXT,
						  j,
						  tex,
						  i);

			status = glCheckFramebufferStatusEXT (GL_FRAMEBUFFER_EXT);
			if (status != GL_FRAMEBUFFER_COMPLETE_EXT) {
				fprintf(stderr, "FBO incomplete\n");
				piglit_report_result(PIGLIT_SKIP);
			}

			glClearColor(colors[i][0],
				     colors[i][1],
				     colors[i][2],
				     0.0);
			glClear(GL_COLOR_BUFFER_BIT);

			if (!piglit_check_gl_error(GL_NO_ERROR))
		                piglit_report_result(PIGLIT_FAIL);
		}
	}

	glDeleteFramebuffersEXT(1, &fb);
	glBindTexture(GL_TEXTURE_CUBE_MAP, tex);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glFrustum(-0.1, 0.1, -0.1, 0.1, 0.1, 1000.0);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glTranslatef(-0.5, -0.5, -1.2);
	glRotatef(68, 0, 1, 0);
	glScalef(2000, 1, 1);

	glEnable(GL_TEXTURE_CUBE_MAP);
	glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

	piglit_set_tolerance_for_bits(7, 7, 7, 7);

	printf("Left: textureCube, Right: textureCubeGradARB\n");
}

static void draw_quad()
{
	glBegin(GL_QUADS);
	glTexCoord3f(-0.5, -0.5, 1);
	glVertex2f(0, 0);
	glTexCoord3f(0.5, -0.5, 1);
	glVertex2f(1, 0);
	glTexCoord3f(0.5, 0.5, 1);
	glVertex2f(1, 1);
	glTexCoord3f(-0.5, 0.5, 1);
	glVertex2f(0, 1);
	glEnd();
}

enum piglit_result piglit_display(void)
{
	GLboolean pass = GL_TRUE;

	glViewport(0, 0, piglit_width, piglit_height);
	glClearColor(0.5, 0.5, 0.5, 0.5);
	glClear(GL_COLOR_BUFFER_BIT);

	glViewport(0, 0, piglit_width/2, piglit_height);
	glUseProgram(prog_tex);
	draw_quad();

	glViewport(piglit_width/2, 0, piglit_width/2, piglit_height);
	glUseProgram(prog_texgrad);
	draw_quad();

	if (!piglit_probe_rect_halves_equal_rgba(0, 0, piglit_width, piglit_height))
		pass = GL_FALSE;

	piglit_present_results();

	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
}
