/*-------------------------------------------------------------------------
 * drawElements Quality Program OpenGL ES 3.0 Module
 * -------------------------------------------------
 *
 * Copyright 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *//*!
 * \file
 * \brief gl_FragDepth tests.
 *//*--------------------------------------------------------------------*/

#include "es3fFragDepthTests.hpp"
#include "tcuVector.hpp"
#include "tcuTestLog.hpp"
#include "tcuSurface.hpp"
#include "tcuImageCompare.hpp"
#include "tcuRenderTarget.hpp"
#include "gluPixelTransfer.hpp"
#include "gluShaderProgram.hpp"
#include "gluDrawUtil.hpp"
#include "deRandom.hpp"
#include "deMath.h"
#include "deString.h"

// For setupDefaultUniforms()
#include "glsShaderRenderCase.hpp"

#include "glwEnums.hpp"
#include "glwFunctions.hpp"

namespace deqp
{
namespace gles3
{
namespace Functional
{

using std::string;
using std::vector;
using tcu::TestLog;
using tcu::Vec2;
using tcu::Vec3;
using tcu::Vec4;

typedef float (*EvalFragDepthFunc)(const Vec2 &coord);

static const char *s_vertexShaderSrc          = "#version 300 es\n"
                                                "in highp vec4 a_position;\n"
                                                "in highp vec2 a_coord;\n"
                                                "out highp vec2 v_coord;\n"
                                                "void main (void)\n"
                                                "{\n"
                                                "    gl_Position = a_position;\n"
                                                "    v_coord = a_coord;\n"
                                                "}\n";
static const char *s_defaultFragmentShaderSrc = "#version 300 es\n"
                                                "uniform highp vec4 u_color;\n"
                                                "layout(location = 0) out mediump vec4 o_color;\n"
                                                "void main (void)\n"
                                                "{\n"
                                                "    o_color = u_color;\n"
                                                "}\n";

template <typename T>
static inline bool compare(uint32_t func, T a, T b)
{
    switch (func)
    {
    case GL_NEVER:
        return false;
    case GL_ALWAYS:
        return true;
    case GL_LESS:
        return a < b;
    case GL_LEQUAL:
        return a <= b;
    case GL_EQUAL:
        return a == b;
    case GL_NOTEQUAL:
        return a != b;
    case GL_GEQUAL:
        return a >= b;
    case GL_GREATER:
        return a > b;
    default:
        DE_ASSERT(false);
        return false;
    }
}

class FragDepthCompareCase : public TestCase
{
public:
    FragDepthCompareCase(Context &context, const char *name, const char *desc, const char *fragSrc,
                         EvalFragDepthFunc evalFunc, uint32_t compareFunc);
    ~FragDepthCompareCase(void);

    IterateResult iterate(void);

private:
    string m_fragSrc;
    EvalFragDepthFunc m_evalFunc;
    uint32_t m_compareFunc;
};

FragDepthCompareCase::FragDepthCompareCase(Context &context, const char *name, const char *desc, const char *fragSrc,
                                           EvalFragDepthFunc evalFunc, uint32_t compareFunc)
    : TestCase(context, name, desc)
    , m_fragSrc(fragSrc)
    , m_evalFunc(evalFunc)
    , m_compareFunc(compareFunc)
{
}

FragDepthCompareCase::~FragDepthCompareCase(void)
{
}

FragDepthCompareCase::IterateResult FragDepthCompareCase::iterate(void)
{
    TestLog &log             = m_testCtx.getLog();
    const glw::Functions &gl = m_context.getRenderContext().getFunctions();
    de::Random rnd(deStringHash(getName()));
    const tcu::RenderTarget &renderTarget = m_context.getRenderContext().getRenderTarget();
    int viewportW                         = de::min(128, renderTarget.getWidth());
    int viewportH                         = de::min(128, renderTarget.getHeight());
    int viewportX                         = rnd.getInt(0, renderTarget.getWidth() - viewportW);
    int viewportY                         = rnd.getInt(0, renderTarget.getHeight() - viewportH);
    tcu::Surface renderedFrame(viewportW, viewportH);
    tcu::Surface referenceFrame(viewportW, viewportH);
    const float constDepth = 0.1f;

    if (renderTarget.getDepthBits() == 0)
        throw tcu::NotSupportedError("Depth buffer is required", "", __FILE__, __LINE__);

    gl.viewport(viewportX, viewportY, viewportW, viewportH);
    gl.clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    gl.enable(GL_DEPTH_TEST);

    static const uint16_t quadIndices[] = {0, 1, 2, 2, 1, 3};

    // Fill viewport with 2 quads - one with constant depth and another with d = [-1..1]
    {
        glu::ShaderProgram basicQuadProgram(m_context.getRenderContext(),
                                            glu::makeVtxFragSources(s_vertexShaderSrc, s_defaultFragmentShaderSrc));

        if (!basicQuadProgram.isOk())
        {
            log << basicQuadProgram;
            TCU_FAIL("Compile failed");
        }

        const float constDepthCoord[]   = {-1.0f, -1.0f, constDepth, 1.0f, -1.0f, +1.0f, constDepth, 1.0f,
                                           0.0f,  -1.0f, constDepth, 1.0f, 0.0f,  +1.0f, constDepth, 1.0f};
        const float varyingDepthCoord[] = {0.0f,  -1.0f, +1.0f, 1.0f, 0.0f,  +1.0f, 0.0f,  1.0f,
                                           +1.0f, -1.0f, 0.0f,  1.0f, +1.0f, +1.0f, -1.0f, 1.0f};

        gl.useProgram(basicQuadProgram.getProgram());
        gl.uniform4f(gl.getUniformLocation(basicQuadProgram.getProgram(), "u_color"), 0.0f, 0.0f, 1.0f, 1.0f);
        gl.depthFunc(GL_ALWAYS);

        {
            glu::VertexArrayBinding posBinding = glu::va::Float("a_position", 4, 4, 0, &constDepthCoord[0]);
            glu::draw(m_context.getRenderContext(), basicQuadProgram.getProgram(), 1, &posBinding,
                      glu::pr::Triangles(DE_LENGTH_OF_ARRAY(quadIndices), &quadIndices[0]));
        }

        {
            glu::VertexArrayBinding posBinding = glu::va::Float("a_position", 4, 4, 0, &varyingDepthCoord[0]);
            glu::draw(m_context.getRenderContext(), basicQuadProgram.getProgram(), 1, &posBinding,
                      glu::pr::Triangles(DE_LENGTH_OF_ARRAY(quadIndices), &quadIndices[0]));
        }

        GLU_EXPECT_NO_ERROR(gl.getError(), "Draw base quads");
    }

    // Render with depth test.
    {
        glu::ShaderProgram program(m_context.getRenderContext(),
                                   glu::makeVtxFragSources(s_vertexShaderSrc, m_fragSrc.c_str()));
        log << program;

        if (!program.isOk())
            TCU_FAIL("Compile failed");

        const float coord[]    = {0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f, 1.0f};
        const float position[] = {-1.0f, -1.0f, +1.0f, 1.0f, -1.0f, +1.0f, 0.0f,  1.0f,
                                  +1.0f, -1.0f, 0.0f,  1.0f, +1.0f, +1.0f, -1.0f, 1.0f};

        gl.useProgram(program.getProgram());
        gl.depthFunc(m_compareFunc);
        gl.uniform4f(gl.getUniformLocation(program.getProgram(), "u_color"), 0.0f, 1.0f, 0.0f, 1.0f);

        // Setup default helper uniforms.
        gls::setupDefaultUniforms(m_context.getRenderContext(), program.getProgram());

        {
            glu::VertexArrayBinding vertexArrays[] = {glu::va::Float("a_position", 4, 4, 0, &position[0]),
                                                      glu::va::Float("a_coord", 2, 4, 0, &coord[0])};
            glu::draw(m_context.getRenderContext(), program.getProgram(), DE_LENGTH_OF_ARRAY(vertexArrays),
                      &vertexArrays[0], glu::pr::Triangles(DE_LENGTH_OF_ARRAY(quadIndices), &quadIndices[0]));
        }

        GLU_EXPECT_NO_ERROR(gl.getError(), "Draw test quad");
    }

    glu::readPixels(m_context.getRenderContext(), viewportX, viewportY, renderedFrame.getAccess());

    // Render reference.
    for (int y = 0; y < referenceFrame.getHeight(); y++)
    {
        float yf = ((float)y + 0.5f) / (float)referenceFrame.getHeight();
        int half = de::clamp((int)((float)referenceFrame.getWidth() * 0.5f + 0.5f), 0, referenceFrame.getWidth());

        // Fill left half - comparison to constant 0.5
        for (int x = 0; x < half; x++)
        {
            float xf   = ((float)x + 0.5f) / (float)referenceFrame.getWidth();
            float d    = m_evalFunc(Vec2(xf, yf));
            bool dpass = compare(m_compareFunc, d, constDepth * 0.5f + 0.5f);

            referenceFrame.setPixel(x, y, dpass ? tcu::RGBA::green() : tcu::RGBA::blue());
        }

        // Fill right half - comparison to interpolated depth
        for (int x = half; x < referenceFrame.getWidth(); x++)
        {
            float xf   = ((float)x + 0.5f) / (float)referenceFrame.getWidth();
            float xh   = ((float)(x - half) + 0.5f) / (float)(referenceFrame.getWidth() - half);
            float rd   = 1.0f - (xh + yf) * 0.5f;
            float d    = m_evalFunc(Vec2(xf, yf));
            bool dpass = compare(m_compareFunc, d, rd);

            referenceFrame.setPixel(x, y, dpass ? tcu::RGBA::green() : tcu::RGBA::blue());
        }
    }

    bool isOk = tcu::fuzzyCompare(log, "Result", "Image comparison result", referenceFrame, renderedFrame, 0.05f,
                                  tcu::COMPARE_LOG_RESULT);
    m_testCtx.setTestResult(isOk ? QP_TEST_RESULT_PASS : QP_TEST_RESULT_FAIL, isOk ? "Pass" : "Fail");
    return STOP;
}

class FragDepthWriteCase : public TestCase
{
public:
    FragDepthWriteCase(Context &context, const char *name, const char *desc, const char *fragSrc,
                       EvalFragDepthFunc evalFunc);
    ~FragDepthWriteCase(void);

    IterateResult iterate(void);

private:
    string m_fragSrc;
    EvalFragDepthFunc m_evalFunc;
};

FragDepthWriteCase::FragDepthWriteCase(Context &context, const char *name, const char *desc, const char *fragSrc,
                                       EvalFragDepthFunc evalFunc)
    : TestCase(context, name, desc)
    , m_fragSrc(fragSrc)
    , m_evalFunc(evalFunc)
{
}

FragDepthWriteCase::~FragDepthWriteCase(void)
{
}

FragDepthWriteCase::IterateResult FragDepthWriteCase::iterate(void)
{
    TestLog &log             = m_testCtx.getLog();
    const glw::Functions &gl = m_context.getRenderContext().getFunctions();
    de::Random rnd(deStringHash(getName()));
    const tcu::RenderTarget &renderTarget = m_context.getRenderContext().getRenderTarget();
    int viewportW                         = de::min(128, renderTarget.getWidth());
    int viewportH                         = de::min(128, renderTarget.getHeight());
    int viewportX                         = rnd.getInt(0, renderTarget.getWidth() - viewportW);
    int viewportY                         = rnd.getInt(0, renderTarget.getHeight() - viewportH);
    tcu::Surface renderedFrame(viewportW, viewportH);
    tcu::Surface referenceFrame(viewportW, viewportH);
    const int numDepthSteps = 16;
    const float depthStep   = 1.0f / (float)(numDepthSteps - 1);

    if (renderTarget.getDepthBits() == 0)
        throw tcu::NotSupportedError("Depth buffer is required", "", __FILE__, __LINE__);

    gl.viewport(viewportX, viewportY, viewportW, viewportH);
    gl.clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    gl.enable(GL_DEPTH_TEST);
    gl.depthFunc(GL_LESS);

    static const uint16_t quadIndices[] = {0, 1, 2, 2, 1, 3};

    // Render with given shader.
    {
        glu::ShaderProgram program(m_context.getRenderContext(),
                                   glu::makeVtxFragSources(s_vertexShaderSrc, m_fragSrc.c_str()));
        log << program;

        if (!program.isOk())
            TCU_FAIL("Compile failed");

        const float coord[]    = {0.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f, 1.0f};
        const float position[] = {-1.0f, -1.0f, +1.0f, 1.0f, -1.0f, +1.0f, 0.0f,  1.0f,
                                  +1.0f, -1.0f, 0.0f,  1.0f, +1.0f, +1.0f, -1.0f, 1.0f};

        gl.useProgram(program.getProgram());
        gl.uniform4f(gl.getUniformLocation(program.getProgram(), "u_color"), 0.0f, 1.0f, 0.0f, 1.0f);

        // Setup default helper uniforms.
        gls::setupDefaultUniforms(m_context.getRenderContext(), program.getProgram());

        {
            glu::VertexArrayBinding vertexArrays[] = {glu::va::Float("a_position", 4, 4, 0, &position[0]),
                                                      glu::va::Float("a_coord", 2, 4, 0, &coord[0])};
            glu::draw(m_context.getRenderContext(), program.getProgram(), DE_LENGTH_OF_ARRAY(vertexArrays),
                      &vertexArrays[0], glu::pr::Triangles(DE_LENGTH_OF_ARRAY(quadIndices), &quadIndices[0]));
        }

        GLU_EXPECT_NO_ERROR(gl.getError(), "Draw test quad");
    }

    // Visualize by rendering full-screen quads with increasing depth and color.
    {
        glu::ShaderProgram program(m_context.getRenderContext(),
                                   glu::makeVtxFragSources(s_vertexShaderSrc, s_defaultFragmentShaderSrc));
        if (!program.isOk())
        {
            log << program;
            TCU_FAIL("Compile failed");
        }

        int posLoc   = gl.getAttribLocation(program.getProgram(), "a_position");
        int colorLoc = gl.getUniformLocation(program.getProgram(), "u_color");

        gl.useProgram(program.getProgram());
        gl.depthMask(GL_FALSE);

        for (int stepNdx = 0; stepNdx < numDepthSteps; stepNdx++)
        {
            float f     = (float)stepNdx * depthStep;
            float depth = f * 2.0f - 1.0f;
            Vec4 color  = Vec4(f, f, f, 1.0f);

            const float position[]             = {-1.0f, -1.0f, depth, 1.0f, -1.0f, +1.0f, depth, 1.0f,
                                                  +1.0f, -1.0f, depth, 1.0f, +1.0f, +1.0f, depth, 1.0f};
            glu::VertexArrayBinding posBinding = glu::va::Float(posLoc, 4, 4, 0, &position[0]);

            gl.uniform4fv(colorLoc, 1, color.getPtr());
            glu::draw(m_context.getRenderContext(), program.getProgram(), 1, &posBinding,
                      glu::pr::Triangles(DE_LENGTH_OF_ARRAY(quadIndices), &quadIndices[0]));
        }

        GLU_EXPECT_NO_ERROR(gl.getError(), "Visualization draw");
    }

    glu::readPixels(m_context.getRenderContext(), viewportX, viewportY, renderedFrame.getAccess());

    // Render reference.
    for (int y = 0; y < referenceFrame.getHeight(); y++)
    {
        for (int x = 0; x < referenceFrame.getWidth(); x++)
        {
            float xf = ((float)x + 0.5f) / (float)referenceFrame.getWidth();
            float yf = ((float)y + 0.5f) / (float)referenceFrame.getHeight();
            float d  = m_evalFunc(Vec2(xf, yf));
            int step = (int)deFloatFloor(d / depthStep);
            int col  = de::clamp(deRoundFloatToInt32((float)step * depthStep * 255.0f), 0, 255);

            referenceFrame.setPixel(x, y, tcu::RGBA(col, col, col, 0xff));
        }
    }

    bool isOk = tcu::fuzzyCompare(log, "Result", "Image comparison result", referenceFrame, renderedFrame, 0.05f,
                                  tcu::COMPARE_LOG_RESULT);
    m_testCtx.setTestResult(isOk ? QP_TEST_RESULT_PASS : QP_TEST_RESULT_FAIL, isOk ? "Pass" : "Fail");
    return STOP;
}

FragDepthTests::FragDepthTests(Context &context) : TestCaseGroup(context, "fragdepth", "gl_FragDepth tests")
{
}

FragDepthTests::~FragDepthTests(void)
{
}

static float evalConstDepth(const Vec2 &coord)
{
    DE_UNREF(coord);
    return 0.5f;
}
static float evalDynamicDepth(const Vec2 &coord)
{
    return (coord.x() + coord.y()) * 0.5f;
}
static float evalNoWrite(const Vec2 &coord)
{
    return 1.0f - (coord.x() + coord.y()) * 0.5f;
}

static float evalDynamicConditionalDepth(const Vec2 &coord)
{
    float d = (coord.x() + coord.y()) * 0.5f;
    if (coord.y() < 0.5f)
        return d;
    else
        return 1.0f - d;
}

void FragDepthTests::init(void)
{
    static const struct
    {
        const char *name;
        const char *desc;
        EvalFragDepthFunc evalFunc;
        const char *fragSrc;
    } cases[] = {{"no_write", "No gl_FragDepth write", evalNoWrite,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "}\n"},
                 {"const", "Const depth write", evalConstDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    gl_FragDepth = 0.5;\n"
                  "}\n"},
                 {"uniform", "Uniform depth write", evalConstDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "uniform highp float uf_half;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    gl_FragDepth = uf_half;\n"
                  "}\n"},
                 {"dynamic", "Dynamic depth write", evalDynamicDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "in highp vec2 v_coord;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    gl_FragDepth = (v_coord.x+v_coord.y)*0.5;\n"
                  "}\n"},
                 {"fragcoord_z", "gl_FragDepth write from gl_FragCoord.z", evalNoWrite,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    gl_FragDepth = gl_FragCoord.z;\n"
                  "}\n"},
                 {"uniform_conditional_write", "Uniform conditional write", evalDynamicDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "uniform bool ub_true;\n"
                  "in highp vec2 v_coord;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    if (ub_true)\n"
                  "        gl_FragDepth = (v_coord.x+v_coord.y)*0.5;\n"
                  "}\n"},
                 {"dynamic_conditional_write", "Uniform conditional write", evalDynamicConditionalDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "uniform bool ub_true;\n"
                  "in highp vec2 v_coord;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    mediump float d = (v_coord.x+v_coord.y)*0.5f;\n"
                  "    if (v_coord.y < 0.5)\n"
                  "        gl_FragDepth = d;\n"
                  "    else\n"
                  "        gl_FragDepth = 1.0 - d;\n"
                  "}\n"},
                 {"uniform_loop_write", "Uniform loop write", evalConstDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "uniform int ui_two;\n"
                  "uniform highp float uf_fourth;\n"
                  "in highp vec2 v_coord;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    gl_FragDepth = 0.0;\n"
                  "    for (int i = 0; i < ui_two; i++)\n"
                  "        gl_FragDepth += uf_fourth;\n"
                  "}\n"},
                 {"write_in_function", "Uniform loop write", evalDynamicDepth,
                  "#version 300 es\n"
                  "uniform highp vec4 u_color;\n"
                  "uniform highp float uf_half;\n"
                  "in highp vec2 v_coord;\n"
                  "layout(location = 0) out mediump vec4 o_color;\n"
                  "void myfunc (highp vec2 coord)\n"
                  "{\n"
                  "    gl_FragDepth = (coord.x+coord.y)*0.5;\n"
                  "}\n"
                  "void main (void)\n"
                  "{\n"
                  "    o_color = u_color;\n"
                  "    myfunc(v_coord);\n"
                  "}\n"}};

    // .write
    tcu::TestCaseGroup *writeGroup = new tcu::TestCaseGroup(m_testCtx, "write", "gl_FragDepth write tests");
    addChild(writeGroup);
    for (int ndx = 0; ndx < DE_LENGTH_OF_ARRAY(cases); ndx++)
        writeGroup->addChild(new FragDepthWriteCase(m_context, cases[ndx].name, cases[ndx].desc, cases[ndx].fragSrc,
                                                    cases[ndx].evalFunc));

    // .compare
    tcu::TestCaseGroup *compareGroup =
        new tcu::TestCaseGroup(m_testCtx, "compare", "gl_FragDepth used with depth comparison");
    addChild(compareGroup);
    for (int ndx = 0; ndx < DE_LENGTH_OF_ARRAY(cases); ndx++)
        compareGroup->addChild(new FragDepthCompareCase(m_context, cases[ndx].name, cases[ndx].desc, cases[ndx].fragSrc,
                                                        cases[ndx].evalFunc, GL_LESS));
}

} // namespace Functional
} // namespace gles3
} // namespace deqp