/*
 * Copyright (c) 2010-2012 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 VMWARE 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.
 */

/**
 * @file
 * Tests OpenGL 3.0 integer textures
 */

#include "piglit-util-gl.h"

PIGLIT_GL_TEST_CONFIG_BEGIN

	config.supports_gl_compat_version = 10;
	config.window_visual = PIGLIT_GL_VISUAL_RGBA | PIGLIT_GL_VISUAL_DOUBLE;
	config.khr_no_error_support = PIGLIT_NO_ERRORS;

PIGLIT_GL_TEST_CONFIG_END

static const char *TestName = "texture-integer";
static GLint TexWidth = 16, TexHeight = 16;
static GLint BiasUniform = -1, TexUniform = -1;
static GLuint iProgram, uProgram;

struct format_info
{
	GLenum IntFormat, BaseFormat;
	GLuint BitsPerChannel;
	GLboolean Signed;
};


static const struct format_info Formats[] = {
	/* { "GL_RGBA", GL_RGBA, GL_RGBA, 8, GL_FALSE },*/
	{ GL_RGBA8I_EXT,   GL_RGBA_INTEGER_EXT, 8,  GL_TRUE  },
	{ GL_RGBA8UI_EXT,  GL_RGBA_INTEGER_EXT, 8,  GL_FALSE },
	{ GL_RGBA16I_EXT,  GL_RGBA_INTEGER_EXT, 16, GL_TRUE  },
	{ GL_RGBA16UI_EXT, GL_RGBA_INTEGER_EXT, 16, GL_FALSE },
	{ GL_RGBA32I_EXT,  GL_RGBA_INTEGER_EXT, 32, GL_TRUE  },
	{ GL_RGBA32UI_EXT, GL_RGBA_INTEGER_EXT, 32, GL_FALSE },

	{ GL_RGB8I_EXT,   GL_RGB_INTEGER_EXT, 8,  GL_TRUE  },
	{ GL_RGB8UI_EXT,  GL_RGB_INTEGER_EXT, 8,  GL_FALSE },
	{ GL_RGB16I_EXT,  GL_RGB_INTEGER_EXT, 16, GL_TRUE  },
	{ GL_RGB16UI_EXT, GL_RGB_INTEGER_EXT, 16, GL_FALSE },
	{ GL_RGB32I_EXT,  GL_RGB_INTEGER_EXT, 32, GL_TRUE  },
	{ GL_RGB32UI_EXT, GL_RGB_INTEGER_EXT, 32, GL_FALSE },

	{ GL_ALPHA8I_EXT,   GL_ALPHA_INTEGER_EXT, 8,  GL_TRUE  },
	{ GL_ALPHA8UI_EXT,  GL_ALPHA_INTEGER_EXT, 8,  GL_FALSE },
	{ GL_ALPHA16I_EXT,  GL_ALPHA_INTEGER_EXT, 16, GL_TRUE  },
	{ GL_ALPHA16UI_EXT, GL_ALPHA_INTEGER_EXT, 16, GL_FALSE },
	{ GL_ALPHA32I_EXT,  GL_ALPHA_INTEGER_EXT, 32, GL_TRUE  },
	{ GL_ALPHA32UI_EXT, GL_ALPHA_INTEGER_EXT, 32, GL_FALSE },

	{ GL_LUMINANCE8I_EXT,   GL_LUMINANCE_INTEGER_EXT, 8,  GL_TRUE  },
	{ GL_LUMINANCE8UI_EXT,  GL_LUMINANCE_INTEGER_EXT, 8,  GL_FALSE },
	{ GL_LUMINANCE16I_EXT,  GL_LUMINANCE_INTEGER_EXT, 16, GL_TRUE  },
	{ GL_LUMINANCE16UI_EXT, GL_LUMINANCE_INTEGER_EXT, 16, GL_FALSE },
	{ GL_LUMINANCE32I_EXT,  GL_LUMINANCE_INTEGER_EXT, 32, GL_TRUE  },
	{ GL_LUMINANCE32UI_EXT, GL_LUMINANCE_INTEGER_EXT, 32, GL_FALSE },

	{ GL_LUMINANCE_ALPHA8I_EXT,   GL_LUMINANCE_ALPHA_INTEGER_EXT, 8,  GL_TRUE  },
	{ GL_LUMINANCE_ALPHA8UI_EXT,  GL_LUMINANCE_ALPHA_INTEGER_EXT, 8,  GL_FALSE },
	{ GL_LUMINANCE_ALPHA16I_EXT,  GL_LUMINANCE_ALPHA_INTEGER_EXT, 16, GL_TRUE  },
	{ GL_LUMINANCE_ALPHA16UI_EXT, GL_LUMINANCE_ALPHA_INTEGER_EXT, 16, GL_FALSE },
	{ GL_LUMINANCE_ALPHA32I_EXT,  GL_LUMINANCE_ALPHA_INTEGER_EXT, 32, GL_TRUE  },
	{ GL_LUMINANCE_ALPHA32UI_EXT, GL_LUMINANCE_ALPHA_INTEGER_EXT, 32, GL_FALSE },

	{ GL_INTENSITY8I_EXT,   GL_RED_INTEGER_EXT, 8,  GL_TRUE  },
	{ GL_INTENSITY8UI_EXT,  GL_RED_INTEGER_EXT, 8,  GL_FALSE },
	{ GL_INTENSITY16I_EXT,  GL_RED_INTEGER_EXT, 16, GL_TRUE  },
	{ GL_INTENSITY16UI_EXT, GL_RED_INTEGER_EXT, 16, GL_FALSE },
	{ GL_INTENSITY32I_EXT,  GL_RED_INTEGER_EXT, 32, GL_TRUE  },
	{ GL_INTENSITY32UI_EXT, GL_RED_INTEGER_EXT, 32, GL_FALSE },
};


/**
 * The basic idea here is to sample the integer texture and then apply
 * a bias vector to bring all the color components into the [0,1] range.
 * One minor issue is that we can't test the full range of 32-bit integer
 * textures since we cast the int values to floats.  But we test enough of
 * the range to be confident.
 */
static const char *FragShaderText =
	"#version 130 \n"
	"uniform vec4 bias; \n"
	"uniform %csampler2D tex; \n"
	"void main() \n"
	"{ \n"
	"   %cvec4 t = texture(tex, gl_TexCoord[0].xy); \n"
	"   gl_FragColor = vec4(t) + bias; \n"
	"} \n";


/**
 * Return the max texture value that can be represented with the given
 * integer format.
 */
static int
get_max_val(const struct format_info *info)
{
	int max;

	switch (info->BitsPerChannel) {
	case 8:
		if (info->Signed)
			max = 127;
		else
			max = 255;
		break;
	case 16:
		if (info->Signed)
			max = 32767;
		else
			max = 65535;
		break;
	case 32:
		if (info->Signed)
			max = 10*1000; /* don't use 0x8fffffff to avoid overflow issues */
		else
			max = 20*1000;
		break;
	default:
		assert(!"unexpected bpp");
		max = 0;
	}

	return max;
}


/**
 * Return the number of color components in the given format.
 */
static int
num_components(GLenum format)
{
	switch (format) {
	case GL_RGBA:
	case GL_RGBA_INTEGER_EXT:
		return 4;
	case GL_RGB_INTEGER_EXT:
		return 3;
	case GL_ALPHA_INTEGER_EXT:
		return 1;
	case GL_LUMINANCE_INTEGER_EXT:
		return 1;
	case GL_LUMINANCE_ALPHA_INTEGER_EXT:
		return 2;
	case GL_RED_INTEGER_EXT:
		return 1;
	default:
		assert(!"unexpected format");
		return 0;
	}
}


/**
 * Fill image buffer with given value.
 */
static void
fill_array(int comps, int texels, void *buf, int bpp, const int val[4])
{
	int i, j;

	switch (bpp) {
	case 8:
		{
			GLubyte *b = (GLubyte *) buf;
			for (i = 0; i < texels; i++) {
				for (j = 0; j < comps; j++) {
					b[i * comps + j] = val[j];
				}
			}
		}
		break;
	case 16:
		{
			GLushort *b = (GLushort *) buf;
			for (i = 0; i < texels; i++) {
				for (j = 0; j < comps; j++) {
					b[i * comps + j] = val[j];
				}
			}
		}
		break;
	case 32:
		{
			GLuint *b = (GLuint *) buf;
			for (i = 0; i < texels; i++) {
				for (j = 0; j < comps; j++) {
					b[i * comps + j] = val[j];
				}
			}
		}
		break;
	default:
		assert(!"unexpected bpp");
	}
}


static GLenum
get_datatype(const struct format_info *info)
{
	switch (info->BitsPerChannel) {
	case 8:
		return info->Signed ? GL_BYTE : GL_UNSIGNED_BYTE;
	case 16:
		return info->Signed ? GL_SHORT : GL_UNSIGNED_SHORT;
	case 32:
		return info->Signed ? GL_INT : GL_UNSIGNED_INT;
	default:
		assert(!"unexpected bpp");
		return 0;
	}
}


/** \return GL_TRUE for pass, GL_FALSE for fail */
static bool
test_format(const struct format_info *info)
{
	const int max = get_max_val(info);
	const int comps = num_components(info->BaseFormat);
	const int texels = TexWidth * TexHeight;
	const GLenum type = get_datatype(info);
	const int w = piglit_width / 10;
	const int h = piglit_height / 10;
	const float error = 2.0 / 255.0; /* XXX fix */
	GLfloat expected[4];
	void *buf;
	int value[4];
	GLfloat result[4], bias[4];
	GLint f;

	/* pick random texture color */
	value[0] = rand() % max;
	value[1] = rand() % max;
	value[2] = rand() % max;
	value[3] = rand() % max;

	/* alloc, fill texture image */
	buf = malloc(comps * texels * info->BitsPerChannel / 8);
	fill_array(comps, texels, buf, info->BitsPerChannel, value);

	glTexImage2D(GL_TEXTURE_2D, 0, info->IntFormat, TexWidth, TexHeight, 0,
					 info->BaseFormat, type, buf);

	/* make sure the teximage call worked */
	if (!piglit_check_gl_error(GL_NO_ERROR))
		return false;

	glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, &f);

	/* setup expected polygon color */
	expected[0] = 0.25;
	expected[1] = 0.50;
	expected[2] = 0.75;
	expected[3] = 1.00;

	/* need to swizzle things depending on texture format */
	switch (info->BaseFormat) {
	case GL_RGBA_INTEGER_EXT:
		/* nothing */
		break;
	case GL_RGB_INTEGER_EXT:
		value[3] = 0.0;
		break;
	case GL_ALPHA_INTEGER_EXT:
		expected[0] = expected[1] = expected[2] = 0.0;
		expected[3] = 0.25;
		value[3] = value[0];
		value[0] = value[1] = value[2] = 0.0;
		break;
	case GL_LUMINANCE_INTEGER_EXT:
		expected[0] = expected[1] = expected[2] = 0.25;
		expected[3] = 1.0;
		value[1] = value[2] = value[0];
		value[3] = 1.0;
		break;
	case GL_LUMINANCE_ALPHA_INTEGER_EXT:
		expected[0] = expected[1] = expected[2] = 0.25;
		value[3] = value[1];
		value[1] = value[2] = value[0];
		break;
	case GL_RED_INTEGER_EXT:
		expected[0] = expected[1] = expected[2] = expected[3] = 0.25;
		value[1] = value[2] = value[3] = value[0];
		break;
	default:
		;
	}

	if (info->Signed) {
		glUseProgram(iProgram);
		BiasUniform = glGetUniformLocation(iProgram, "bias");
		TexUniform = glGetUniformLocation(iProgram, "tex");
	} else {
		glUseProgram(uProgram);
		BiasUniform = glGetUniformLocation(uProgram, "bias");
		TexUniform = glGetUniformLocation(uProgram, "tex");
	}


	/* tex unit zero */
	glUniform1i(TexUniform, 0);
	/* compute, set test bias */
	bias[0] = expected[0] - value[0];
	bias[1] = expected[1] - value[1];
	bias[2] = expected[2] - value[2];
	bias[3] = expected[3] - value[3];
	glUniform4fv(BiasUniform, 1, bias);

	/* draw */
	glClearColor(0, 1, 1, 0);
	glClear(GL_COLOR_BUFFER_BIT);
	glBegin(GL_POLYGON);
	glTexCoord2f(0, 0);	glVertex2f(0, 0);
	glTexCoord2f(1, 0);	glVertex2f(w, 0);
	glTexCoord2f(1, 1);	glVertex2f(w, h);
	glTexCoord2f(0, 1);	glVertex2f(0, h);
	glEnd();

	/* test */
	glReadPixels(w/2, h/2, 1, 1, GL_RGBA, GL_FLOAT, result);

	if (fabsf(result[0] - expected[0]) > error ||
		 fabsf(result[1] - expected[1]) > error ||
		 fabsf(result[2] - expected[2]) > error ||
		 fabsf(result[3] - expected[3]) > error) {
		fprintf(stderr, "%s: failure with format %s:\n", TestName,
			piglit_get_gl_enum_name(info->IntFormat));
		fprintf(stderr, "  texture color = %d, %d, %d, %d\n",
				  value[0], value[1], value[2], value[3]);
		fprintf(stderr, "  expected color = %g, %g, %g, %g\n",
				  expected[0], expected[1], expected[2], expected[3]);
		fprintf(stderr, "  result color = %g, %g, %g, %g\n",
				  result[0], result[1], result[2], result[3]);
		return false;
	}

	glUseProgram(0);

	piglit_present_results();

	free(buf);

	return GL_TRUE;
}


enum piglit_result
piglit_display(void)
{
	int f, i;

	for (f = 0; f < ARRAY_SIZE(Formats); f++) {
		for (i = 0; i < 5; i++) {
			if (!test_format(&Formats[f]))
				return PIGLIT_FAIL;
		}
	}

	return PIGLIT_PASS;
}


void
piglit_init(int argc, char **argv)
{
        static GLuint tex;
	char shaderText[1024];

	piglit_require_gl_version(30);

	sprintf(shaderText, FragShaderText, 'i', 'i');
	iProgram = piglit_build_simple_program(NULL, shaderText);

	sprintf(shaderText, FragShaderText, 'u', 'u');
	uProgram = piglit_build_simple_program(NULL, shaderText);

	glGenTextures(1, &tex);
	glBindTexture(GL_TEXTURE_2D, tex);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

	piglit_ortho_projection(piglit_width, piglit_height, GL_FALSE);
}
