//
// Copyright (c) 2014 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// TypeTracking_test.cpp:
//   Test for tracking types resulting from math operations, including their
//   precision.
//

#include "angle_gl.h"
#include "gtest/gtest.h"
#include "GLSLANG/ShaderLang.h"
#include "compiler/translator/TranslatorESSL.h"

class TypeTrackingTest : public testing::Test
{
  public:
    TypeTrackingTest() {}

  protected:
    virtual void SetUp()
    {
        ShBuiltInResources resources;
        ShInitBuiltInResources(&resources);

        mTranslator = new TranslatorESSL(GL_FRAGMENT_SHADER, SH_GLES3_SPEC);
        ASSERT_TRUE(mTranslator->Init(resources));
    }

    virtual void TearDown()
    {
        delete mTranslator;
    }

    void compile(const std::string& shaderString)
    {
        const char *shaderStrings[] = { shaderString.c_str() };
        bool compilationSuccess = mTranslator->compile(shaderStrings, 1, SH_INTERMEDIATE_TREE);
        TInfoSink &infoSink = mTranslator->getInfoSink();
        mInfoLog = infoSink.info.c_str();
        if (!compilationSuccess)
            FAIL() << "Shader compilation failed " << mInfoLog;
    }

    bool foundInIntermediateTree(const char* stringToFind)
    {
        return mInfoLog.find(stringToFind) != std::string::npos;
    }

  private:
    TranslatorESSL *mTranslator;
    std::string mInfoLog;
};

TEST_F(TypeTrackingTest, FunctionPrototypeMangling)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "float fun(float a);\n"
        "uniform float f;\n"
        "void main() {\n"
        "   float ff = fun(f);\n"
        "   gl_FragColor = vec4(ff);\n"
        "}\n"
        "float fun(float a) {\n"
        "   return a * 2.0;\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("Function Prototype: fun(f1;"));
    ASSERT_TRUE(foundInIntermediateTree("Function Definition: fun(f1;"));
};

TEST_F(TypeTrackingTest, BuiltInFunctionResultPrecision)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform float f;\n"
        "void main() {\n"
        "   float ff = sin(f);\n"
        "   gl_FragColor = vec4(ff);\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("sine (mediump float)"));
};

TEST_F(TypeTrackingTest, BinaryMathResultPrecision)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform float f;\n"
        "void main() {\n"
        "   float ff = f * 0.5;\n"
        "   gl_FragColor = vec4(ff);\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("multiply (mediump float)"));
};

TEST_F(TypeTrackingTest, BuiltInVecFunctionResultTypeAndPrecision)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform vec2 a;\n"
        "void main() {\n"
        "   float b = length(a);\n"
        "   float c = dot(a, vec2(0.5));\n"
        "   float d = distance(vec2(0.5), a);\n"
        "   gl_FragColor = vec4(b, c, d, 1.0);\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("length (mediump float)"));
    ASSERT_TRUE(foundInIntermediateTree("dot-product (mediump float)"));
    ASSERT_TRUE(foundInIntermediateTree("distance (mediump float)"));
};

TEST_F(TypeTrackingTest, BuiltInFunctionChoosesHigherPrecision)
{
    const std::string &shaderString =
        "precision lowp float;\n"
        "uniform mediump vec2 a;\n"
        "uniform lowp vec2 b;\n"
        "void main() {\n"
        "   float c = dot(a, b);\n"
        "   float d = distance(b, a);\n"
        "   gl_FragColor = vec4(c, d, 0.0, 1.0);\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("dot-product (mediump float)"));
    ASSERT_TRUE(foundInIntermediateTree("distance (mediump float)"));
};

TEST_F(TypeTrackingTest, BuiltInBoolFunctionResultType)
{
    const std::string &shaderString =
        "uniform bvec4 bees;\n"
        "void main() {\n"
        "   bool b = any(bees);\n"
        "   bool c = all(bees);\n"
        "   bvec4 d = not(bees);\n"
        "   gl_FragColor = vec4(b ? 1.0 : 0.0, c ? 1.0 : 0.0, d.x ? 1.0 : 0.0, 1.0);\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("any (bool)"));
    ASSERT_TRUE(foundInIntermediateTree("all (bool)"));
    ASSERT_TRUE(foundInIntermediateTree("Negate conditional (4-component vector of bool)"));
};

TEST_F(TypeTrackingTest, BuiltInVecToBoolFunctionResultType)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform vec2 apples;\n"
        "uniform vec2 oranges;\n"
        "uniform ivec2 foo;\n"
        "uniform ivec2 bar;\n"
        "void main() {\n"
        "   bvec2 a = lessThan(apples, oranges);\n"
        "   bvec2 b = greaterThan(foo, bar);\n"
        "   gl_FragColor = vec4(any(a) ? 1.0 : 0.0, any(b) ? 1.0 : 0.0, 0.0, 1.0);\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("Less Than (2-component vector of bool)"));
    ASSERT_TRUE(foundInIntermediateTree("Greater Than (2-component vector of bool)"));
};

TEST_F(TypeTrackingTest, Texture2DResultTypeAndPrecision)
{
    // ESSL spec section 4.5.3: sampler2D and samplerCube are lowp by default
    // ESSL spec section 8: For the texture functions, the precision of the return type matches the precision of the sampler type.
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform sampler2D s;\n"
        "uniform vec2 a;\n"
        "void main() {\n"
        "   vec4 c = texture2D(s, a);\n"
        "   gl_FragColor = c;\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("texture2D(s21;vf2; (lowp 4-component vector of float)"));
};

TEST_F(TypeTrackingTest, TextureCubeResultTypeAndPrecision)
{
    // ESSL spec section 4.5.3: sampler2D and samplerCube are lowp by default
    // ESSL spec section 8: For the texture functions, the precision of the return type matches the precision of the sampler type.
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform samplerCube sc;\n"
        "uniform vec3 a;\n"
        "void main() {\n"
        "   vec4 c = textureCube(sc, a);\n"
        "   gl_FragColor = c;\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("textureCube(sC1;vf3; (lowp 4-component vector of float)"));
};

TEST_F(TypeTrackingTest, TextureSizeResultTypeAndPrecision)
{
    // ESSL 3.0 spec section 8: textureSize has predefined precision highp
    const std::string &shaderString =
        "#version 300 es\n"
        "precision mediump float;\n"
        "out vec4 my_FragColor;\n"
        "uniform sampler2D s;\n"
        "void main() {\n"
        "   ivec2 size = textureSize(s, 0);\n"
        "   if (size.x > 100) {\n"
        "       my_FragColor = vec4(0.0, 1.0, 0.0, 1.0);\n"
        "   } else {\n"
        "       my_FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n"
        "   }\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("textureSize(s21;i1; (highp 2-component vector of int)"));
};

TEST_F(TypeTrackingTest, BuiltInConstructorResultTypeAndPrecision)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform float u1;\n"
        "uniform float u2;\n"
        "uniform float u3;\n"
        "uniform float u4;\n"
        "void main() {\n"
        "   vec4 a = vec4(u1, u2, u3, u4);\n"
        "   gl_FragColor = a;\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("Construct vec4 (mediump 4-component vector of float)"));
};

TEST_F(TypeTrackingTest, StructConstructorResultNoPrecision)
{
    const std::string &shaderString =
        "precision mediump float;\n"
        "uniform vec4 u1;\n"
        "uniform vec4 u2;\n"
        "struct S { highp vec4 a; highp vec4 b; };\n"
        "void main() {\n"
        "   S s = S(u1, u2);\n"
        "   gl_FragColor = s.a;\n"
        "}\n";
    compile(shaderString);
    ASSERT_TRUE(foundInIntermediateTree("Construct structure (structure)"));
};
