//
// Copyright 2015 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.
//

// ProgramGL.cpp: Implements the class methods for ProgramGL.

#include "libANGLE/renderer/gl/ProgramGL.h"

#include "common/debug.h"
#include "common/utilities.h"
#include "libANGLE/renderer/gl/FunctionsGL.h"
#include "libANGLE/renderer/gl/ShaderGL.h"
#include "libANGLE/renderer/gl/StateManagerGL.h"
#include "libANGLE/renderer/gl/WorkaroundsGL.h"
#include "libANGLE/Uniform.h"
#include "platform/Platform.h"

namespace rx
{

ProgramGL::ProgramGL(const gl::ProgramState &data,
                     const FunctionsGL *functions,
                     const WorkaroundsGL &workarounds,
                     StateManagerGL *stateManager)
    : ProgramImpl(data),
      mFunctions(functions),
      mWorkarounds(workarounds),
      mStateManager(stateManager),
      mProgramID(0)
{
    ASSERT(mFunctions);
    ASSERT(mStateManager);

    mProgramID = mFunctions->createProgram();
}

ProgramGL::~ProgramGL()
{
    mFunctions->deleteProgram(mProgramID);
    mProgramID = 0;
}

LinkResult ProgramGL::load(gl::InfoLog &infoLog, gl::BinaryInputStream *stream)
{
    preLink();

    // Read the binary format, size and blob
    GLenum binaryFormat   = stream->readInt<GLenum>();
    GLint binaryLength    = stream->readInt<GLint>();
    const uint8_t *binary = stream->data() + stream->offset();
    stream->skip(binaryLength);

    // Load the binary
    mFunctions->programBinary(mProgramID, binaryFormat, binary, binaryLength);

    // Verify that the program linked
    if (!checkLinkStatus(infoLog))
    {
        return LinkResult(false, gl::Error(GL_NO_ERROR));
    }

    postLink();

    return LinkResult(true, gl::Error(GL_NO_ERROR));
}

gl::Error ProgramGL::save(gl::BinaryOutputStream *stream)
{
    GLint binaryLength = 0;
    mFunctions->getProgramiv(mProgramID, GL_PROGRAM_BINARY_LENGTH, &binaryLength);

    std::vector<uint8_t> binary(binaryLength);
    GLenum binaryFormat = GL_NONE;
    mFunctions->getProgramBinary(mProgramID, binaryLength, &binaryLength, &binaryFormat,
                                 &binary[0]);

    stream->writeInt(binaryFormat);
    stream->writeInt(binaryLength);
    stream->writeBytes(&binary[0], binaryLength);

    return gl::Error(GL_NO_ERROR);
}

void ProgramGL::setBinaryRetrievableHint(bool retrievable)
{
    // glProgramParameteri isn't always available on ES backends.
    if (mFunctions->programParameteri)
    {
        mFunctions->programParameteri(mProgramID, GL_PROGRAM_BINARY_RETRIEVABLE_HINT,
                                      retrievable ? GL_TRUE : GL_FALSE);
    }
}

LinkResult ProgramGL::link(const gl::ContextState &data, gl::InfoLog &infoLog)
{
    preLink();

    // Set the transform feedback state
    std::vector<const GLchar *> transformFeedbackVaryings;
    for (const auto &tfVarying : mState.getTransformFeedbackVaryingNames())
    {
        transformFeedbackVaryings.push_back(tfVarying.c_str());
    }

    if (transformFeedbackVaryings.empty())
    {
        if (mFunctions->transformFeedbackVaryings)
        {
            mFunctions->transformFeedbackVaryings(mProgramID, 0, nullptr,
                                                  mState.getTransformFeedbackBufferMode());
        }
    }
    else
    {
        ASSERT(mFunctions->transformFeedbackVaryings);
        mFunctions->transformFeedbackVaryings(
            mProgramID, static_cast<GLsizei>(transformFeedbackVaryings.size()),
            &transformFeedbackVaryings[0], mState.getTransformFeedbackBufferMode());
    }

    const ShaderGL *vertexShaderGL   = GetImplAs<ShaderGL>(mState.getAttachedVertexShader());
    const ShaderGL *fragmentShaderGL = GetImplAs<ShaderGL>(mState.getAttachedFragmentShader());

    // Attach the shaders
    mFunctions->attachShader(mProgramID, vertexShaderGL->getShaderID());
    mFunctions->attachShader(mProgramID, fragmentShaderGL->getShaderID());

    // Bind attribute locations to match the GL layer.
    for (const sh::Attribute &attribute : mState.getAttributes())
    {
        if (!attribute.staticUse)
        {
            continue;
        }

        mFunctions->bindAttribLocation(mProgramID, attribute.location, attribute.name.c_str());
    }

    // Link and verify
    mFunctions->linkProgram(mProgramID);

    // Detach the shaders
    mFunctions->detachShader(mProgramID, vertexShaderGL->getShaderID());
    mFunctions->detachShader(mProgramID, fragmentShaderGL->getShaderID());

    // Verify the link
    if (!checkLinkStatus(infoLog))
    {
        return LinkResult(false, gl::Error(GL_NO_ERROR));
    }

    if (mWorkarounds.alwaysCallUseProgramAfterLink)
    {
        mStateManager->forceUseProgram(mProgramID);
    }

    postLink();

    return LinkResult(true, gl::Error(GL_NO_ERROR));
}

GLboolean ProgramGL::validate(const gl::Caps & /*caps*/, gl::InfoLog * /*infoLog*/)
{
    // TODO(jmadill): implement validate
    return true;
}

void ProgramGL::setUniform1fv(GLint location, GLsizei count, const GLfloat *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform1fv(uniLoc(location), count, v);
}

void ProgramGL::setUniform2fv(GLint location, GLsizei count, const GLfloat *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform2fv(uniLoc(location), count, v);
}

void ProgramGL::setUniform3fv(GLint location, GLsizei count, const GLfloat *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform3fv(uniLoc(location), count, v);
}

void ProgramGL::setUniform4fv(GLint location, GLsizei count, const GLfloat *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform4fv(uniLoc(location), count, v);
}

void ProgramGL::setUniform1iv(GLint location, GLsizei count, const GLint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform1iv(uniLoc(location), count, v);

    const gl::VariableLocation &locationEntry = mState.getUniformLocations()[location];

    size_t samplerIndex = mUniformIndexToSamplerIndex[locationEntry.index];
    if (samplerIndex != GL_INVALID_INDEX)
    {
        std::vector<GLuint> &boundTextureUnits = mSamplerBindings[samplerIndex].boundTextureUnits;

        size_t copyCount =
            std::max<size_t>(count, boundTextureUnits.size() - locationEntry.element);
        std::copy(v, v + copyCount, boundTextureUnits.begin() + locationEntry.element);
    }
}

void ProgramGL::setUniform2iv(GLint location, GLsizei count, const GLint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform2iv(uniLoc(location), count, v);
}

void ProgramGL::setUniform3iv(GLint location, GLsizei count, const GLint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform3iv(uniLoc(location), count, v);
}

void ProgramGL::setUniform4iv(GLint location, GLsizei count, const GLint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform4iv(uniLoc(location), count, v);
}

void ProgramGL::setUniform1uiv(GLint location, GLsizei count, const GLuint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform1uiv(location, count, v);
}

void ProgramGL::setUniform2uiv(GLint location, GLsizei count, const GLuint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform2uiv(uniLoc(location), count, v);
}

void ProgramGL::setUniform3uiv(GLint location, GLsizei count, const GLuint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform3uiv(uniLoc(location), count, v);
}

void ProgramGL::setUniform4uiv(GLint location, GLsizei count, const GLuint *v)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniform4uiv(uniLoc(location), count, v);
}

void ProgramGL::setUniformMatrix2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix2fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix3fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix4fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix2x3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix2x3fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix3x2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix3x2fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix2x4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix2x4fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix4x2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix4x2fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix3x4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix3x4fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformMatrix4x3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value)
{
    mStateManager->useProgram(mProgramID);
    mFunctions->uniformMatrix4x3fv(uniLoc(location), count, transpose, value);
}

void ProgramGL::setUniformBlockBinding(GLuint uniformBlockIndex, GLuint uniformBlockBinding)
{
    // Lazy init
    if (mUniformBlockRealLocationMap.empty())
    {
        mUniformBlockRealLocationMap.reserve(mState.getUniformBlocks().size());
        for (const gl::UniformBlock &uniformBlock : mState.getUniformBlocks())
        {
            const std::string &nameWithIndex = uniformBlock.nameWithArrayIndex();
            GLuint blockIndex = mFunctions->getUniformBlockIndex(mProgramID, nameWithIndex.c_str());
            mUniformBlockRealLocationMap.push_back(blockIndex);
        }
    }

    GLuint realBlockIndex = mUniformBlockRealLocationMap[uniformBlockIndex];
    if (realBlockIndex != GL_INVALID_INDEX)
    {
        mFunctions->uniformBlockBinding(mProgramID, realBlockIndex, uniformBlockBinding);
    }
}

GLuint ProgramGL::getProgramID() const
{
    return mProgramID;
}

const std::vector<SamplerBindingGL> &ProgramGL::getAppliedSamplerUniforms() const
{
    return mSamplerBindings;
}

bool ProgramGL::getUniformBlockSize(const std::string &blockName, size_t *sizeOut) const
{
    ASSERT(mProgramID != 0u);

    GLuint blockIndex = mFunctions->getUniformBlockIndex(mProgramID, blockName.c_str());
    if (blockIndex == GL_INVALID_INDEX)
    {
        *sizeOut = 0;
        return false;
    }

    GLint dataSize = 0;
    mFunctions->getActiveUniformBlockiv(mProgramID, blockIndex, GL_UNIFORM_BLOCK_DATA_SIZE,
                                        &dataSize);
    *sizeOut = static_cast<size_t>(dataSize);
    return true;
}

bool ProgramGL::getUniformBlockMemberInfo(const std::string &memberUniformName,
                                          sh::BlockMemberInfo *memberInfoOut) const
{
    GLuint uniformIndex;
    const GLchar *memberNameGLStr = memberUniformName.c_str();
    mFunctions->getUniformIndices(mProgramID, 1, &memberNameGLStr, &uniformIndex);

    if (uniformIndex == GL_INVALID_INDEX)
    {
        *memberInfoOut = sh::BlockMemberInfo::getDefaultBlockInfo();
        return false;
    }

    mFunctions->getActiveUniformsiv(mProgramID, 1, &uniformIndex, GL_UNIFORM_OFFSET,
                                    &memberInfoOut->offset);
    mFunctions->getActiveUniformsiv(mProgramID, 1, &uniformIndex, GL_UNIFORM_ARRAY_STRIDE,
                                    &memberInfoOut->arrayStride);
    mFunctions->getActiveUniformsiv(mProgramID, 1, &uniformIndex, GL_UNIFORM_MATRIX_STRIDE,
                                    &memberInfoOut->matrixStride);

    // TODO(jmadill): possibly determine this at the gl::Program level.
    GLint isRowMajorMatrix = 0;
    mFunctions->getActiveUniformsiv(mProgramID, 1, &uniformIndex, GL_UNIFORM_IS_ROW_MAJOR,
                                    &isRowMajorMatrix);
    memberInfoOut->isRowMajorMatrix = isRowMajorMatrix != GL_FALSE;
    return true;
}

void ProgramGL::preLink()
{
    // Reset the program state
    mUniformRealLocationMap.clear();
    mUniformBlockRealLocationMap.clear();
    mSamplerBindings.clear();
    mUniformIndexToSamplerIndex.clear();
}

bool ProgramGL::checkLinkStatus(gl::InfoLog &infoLog)
{
    GLint linkStatus = GL_FALSE;
    mFunctions->getProgramiv(mProgramID, GL_LINK_STATUS, &linkStatus);
    if (linkStatus == GL_FALSE)
    {
        // Linking failed, put the error into the info log
        GLint infoLogLength = 0;
        mFunctions->getProgramiv(mProgramID, GL_INFO_LOG_LENGTH, &infoLogLength);

        std::string warning;

        // Info log length includes the null terminator, so 1 means that the info log is an empty
        // string.
        if (infoLogLength > 1)
        {
            std::vector<char> buf(infoLogLength);
            mFunctions->getProgramInfoLog(mProgramID, infoLogLength, nullptr, &buf[0]);

            mFunctions->deleteProgram(mProgramID);
            mProgramID = 0;

            infoLog << buf.data();

            warning = FormatString("Program link failed unexpectedly: %s", buf.data());
        }
        else
        {
            warning = "Program link failed unexpectedly with no info log.";
        }
        ANGLEPlatformCurrent()->logWarning(warning.c_str());
        TRACE("\n%s", warning.c_str());

        // TODO, return GL_OUT_OF_MEMORY or just fail the link? This is an unexpected case
        return false;
    }

    return true;
}

void ProgramGL::postLink()
{
    // Query the uniform information
    ASSERT(mUniformRealLocationMap.empty());
    const auto &uniformLocations = mState.getUniformLocations();
    const auto &uniforms = mState.getUniforms();
    mUniformRealLocationMap.resize(uniformLocations.size(), GL_INVALID_INDEX);
    for (size_t uniformLocation = 0; uniformLocation < uniformLocations.size(); uniformLocation++)
    {
        const auto &entry = uniformLocations[uniformLocation];
        if (!entry.used)
        {
            continue;
        }

        // From the spec:
        // "Locations for sequential array indices are not required to be sequential."
        const gl::LinkedUniform &uniform = uniforms[entry.index];
        std::stringstream fullNameStr;
        fullNameStr << uniform.name;
        if (uniform.isArray())
        {
            fullNameStr << "[" << entry.element << "]";
        }
        const std::string &fullName = fullNameStr.str();

        GLint realLocation = mFunctions->getUniformLocation(mProgramID, fullName.c_str());
        mUniformRealLocationMap[uniformLocation] = realLocation;
    }

    mUniformIndexToSamplerIndex.resize(mState.getUniforms().size(), GL_INVALID_INDEX);

    for (size_t uniformId = 0; uniformId < uniforms.size(); ++uniformId)
    {
        const gl::LinkedUniform &linkedUniform = uniforms[uniformId];

        if (!linkedUniform.isSampler() || !linkedUniform.staticUse)
            continue;

        mUniformIndexToSamplerIndex[uniformId] = mSamplerBindings.size();

        // If uniform is a sampler type, insert it into the mSamplerBindings array
        SamplerBindingGL samplerBinding;
        samplerBinding.textureType = gl::SamplerTypeToTextureType(linkedUniform.type);
        samplerBinding.boundTextureUnits.resize(linkedUniform.elementCount(), 0);
        mSamplerBindings.push_back(samplerBinding);
    }
}

}  // namespace rx
