/*-------------------------------------------------------------------------
 * drawElements Quality Program OpenGL ES Utilities
 * ------------------------------------------------
 *
 * 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 OpenGL ES context wrapper that uses FBO as default framebuffer.
 *//*--------------------------------------------------------------------*/

#include "gluFboRenderContext.hpp"
#include "gluContextFactory.hpp"
#include "gluRenderConfig.hpp"
#include "glwEnums.hpp"
#include "glwFunctions.hpp"
#include "tcuCommandLine.hpp"
#include "gluTextureUtil.hpp"
#include "tcuTextureUtil.hpp"

#include <sstream>

namespace glu
{

static int getNumDepthBits(const tcu::TextureFormat &format)
{
    if (format.order == tcu::TextureFormat::DS)
    {
        const tcu::TextureFormat depthOnlyFormat =
            tcu::getEffectiveDepthStencilTextureFormat(format, tcu::Sampler::MODE_DEPTH);
        return tcu::getTextureFormatBitDepth(depthOnlyFormat).x();
    }
    else if (format.order == tcu::TextureFormat::D)
        return tcu::getTextureFormatBitDepth(format).x();
    else
        return 0;
}

static int getNumStencilBits(const tcu::TextureFormat &format)
{
    if (format.order == tcu::TextureFormat::DS)
    {
        const tcu::TextureFormat stencilOnlyFormat =
            tcu::getEffectiveDepthStencilTextureFormat(format, tcu::Sampler::MODE_STENCIL);
        return tcu::getTextureFormatBitDepth(stencilOnlyFormat).x();
    }
    else if (format.order == tcu::TextureFormat::S)
        return tcu::getTextureFormatBitDepth(format).x();
    else
        return 0;
}

static tcu::PixelFormat getPixelFormat(uint32_t colorFormat)
{
    const tcu::IVec4 bits = tcu::getTextureFormatBitDepth(glu::mapGLInternalFormat(colorFormat));
    return tcu::PixelFormat(bits[0], bits[1], bits[2], bits[3]);
}

static void getDepthStencilBits(uint32_t depthStencilFormat, int *depthBits, int *stencilBits)
{
    const tcu::TextureFormat combinedFormat = glu::mapGLInternalFormat(depthStencilFormat);

    *depthBits   = getNumDepthBits(combinedFormat);
    *stencilBits = getNumStencilBits(combinedFormat);
}

uint32_t chooseColorFormat(const glu::RenderConfig &config)
{
    static const uint32_t s_formats[] = {GL_RGBA8, GL_RGB8, GL_RG8, GL_R8, GL_RGBA4, GL_RGB5_A1, GL_RGB565, GL_RGB5};

    for (int fmtNdx = 0; fmtNdx < DE_LENGTH_OF_ARRAY(s_formats); fmtNdx++)
    {
        const uint32_t format = s_formats[fmtNdx];
        const tcu::IVec4 bits = tcu::getTextureFormatBitDepth(glu::mapGLInternalFormat(format));

        if (config.redBits != glu::RenderConfig::DONT_CARE && config.redBits != bits[0])
            continue;

        if (config.greenBits != glu::RenderConfig::DONT_CARE && config.greenBits != bits[1])
            continue;

        if (config.blueBits != glu::RenderConfig::DONT_CARE && config.blueBits != bits[2])
            continue;

        if (config.alphaBits != glu::RenderConfig::DONT_CARE && config.alphaBits != bits[3])
            continue;

        return format;
    }

    return 0;
}

uint32_t chooseDepthStencilFormat(const glu::RenderConfig &config)
{
    static const uint32_t s_formats[] = {GL_DEPTH32F_STENCIL8, GL_DEPTH24_STENCIL8,  GL_DEPTH_COMPONENT32F,
                                         GL_DEPTH_COMPONENT24, GL_DEPTH_COMPONENT16, GL_STENCIL_INDEX8};

    for (int fmtNdx = 0; fmtNdx < DE_LENGTH_OF_ARRAY(s_formats); fmtNdx++)
    {
        const uint32_t format                   = s_formats[fmtNdx];
        const tcu::TextureFormat combinedFormat = glu::mapGLInternalFormat(format);
        const int depthBits                     = getNumDepthBits(combinedFormat);
        const int stencilBits                   = getNumStencilBits(combinedFormat);

        if (config.depthBits != glu::RenderConfig::DONT_CARE && config.depthBits != depthBits)
            continue;

        if (config.stencilBits != glu::RenderConfig::DONT_CARE && config.stencilBits != stencilBits)
            continue;

        return format;
    }

    return 0;
}

FboRenderContext::FboRenderContext(RenderContext *context, const RenderConfig &config)
    : m_context(context)
    , m_framebuffer(0)
    , m_colorBuffer(0)
    , m_depthStencilBuffer(0)
    , m_renderTarget()
{
    try
    {
        createFramebuffer(config);
    }
    catch (...)
    {
        destroyFramebuffer();
        throw;
    }
}

FboRenderContext::FboRenderContext(const ContextFactory &factory, const RenderConfig &config,
                                   const tcu::CommandLine &cmdLine)
    : m_context(DE_NULL)
    , m_framebuffer(0)
    , m_colorBuffer(0)
    , m_depthStencilBuffer(0)
    , m_renderTarget()
{
    try
    {
        RenderConfig nativeRenderConfig;
        nativeRenderConfig.type             = config.type;
        nativeRenderConfig.windowVisibility = config.windowVisibility;
        // \note All other properties are defaults, mostly DONT_CARE
        m_context = factory.createContext(nativeRenderConfig, cmdLine, DE_NULL);
        createFramebuffer(config);
    }
    catch (...)
    {
        delete m_context;
        throw;
    }
}

FboRenderContext::~FboRenderContext(void)
{
    // \todo [2013-04-08 pyry] Do we want to destry FBO before destroying context?
    delete m_context;
}

void FboRenderContext::postIterate(void)
{
    // \todo [2012-11-27 pyry] Blit to default framebuffer in ES3?
    m_context->getFunctions().finish();
}

void FboRenderContext::makeCurrent(void)
{
    m_context->makeCurrent();
}

void FboRenderContext::createFramebuffer(const RenderConfig &config)
{
    DE_ASSERT(m_framebuffer == 0 && m_colorBuffer == 0 && m_depthStencilBuffer == 0);

    const glw::Functions &gl          = m_context->getFunctions();
    const uint32_t colorFormat        = chooseColorFormat(config);
    const uint32_t depthStencilFormat = chooseDepthStencilFormat(config);
    int width                         = config.width;
    int height                        = config.height;
    tcu::PixelFormat pixelFormat;
    int depthBits   = 0;
    int stencilBits = 0;

    if (config.numSamples > 0 && !gl.renderbufferStorageMultisample)
        throw tcu::NotSupportedError("Multisample FBO is not supported");

    if (colorFormat == 0)
        throw tcu::NotSupportedError("Unsupported color attachment format");

    if (width == glu::RenderConfig::DONT_CARE || height == glu::RenderConfig::DONT_CARE)
    {
        int maxSize = 0;
        gl.getIntegerv(GL_MAX_RENDERBUFFER_SIZE, &maxSize);

        width  = (width == glu::RenderConfig::DONT_CARE) ? maxSize : width;
        height = (height == glu::RenderConfig::DONT_CARE) ? maxSize : height;
    }

    {
        pixelFormat = getPixelFormat(colorFormat);

        gl.genRenderbuffers(1, &m_colorBuffer);
        gl.bindRenderbuffer(GL_RENDERBUFFER, m_colorBuffer);

        if (config.numSamples > 0)
            gl.renderbufferStorageMultisample(GL_RENDERBUFFER, config.numSamples, colorFormat, width, height);
        else
            gl.renderbufferStorage(GL_RENDERBUFFER, colorFormat, width, height);

        gl.bindRenderbuffer(GL_RENDERBUFFER, 0);
        GLU_EXPECT_NO_ERROR(gl.getError(), "Creating color renderbuffer");
    }

    if (depthStencilFormat != GL_NONE)
    {
        getDepthStencilBits(depthStencilFormat, &depthBits, &stencilBits);

        gl.genRenderbuffers(1, &m_depthStencilBuffer);
        gl.bindRenderbuffer(GL_RENDERBUFFER, m_depthStencilBuffer);

        if (config.numSamples > 0)
            gl.renderbufferStorageMultisample(GL_RENDERBUFFER, config.numSamples, depthStencilFormat, width, height);
        else
            gl.renderbufferStorage(GL_RENDERBUFFER, depthStencilFormat, width, height);

        gl.bindRenderbuffer(GL_RENDERBUFFER, 0);
        GLU_EXPECT_NO_ERROR(gl.getError(), "Creating depth / stencil renderbuffer");
    }

    gl.genFramebuffers(1, &m_framebuffer);
    gl.bindFramebuffer(GL_FRAMEBUFFER, m_framebuffer);

    if (m_colorBuffer)
        gl.framebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, m_colorBuffer);

    if (m_depthStencilBuffer)
    {
        if (depthBits > 0)
            gl.framebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, m_depthStencilBuffer);

        if (stencilBits > 0)
            gl.framebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_RENDERBUFFER, m_depthStencilBuffer);
    }

    GLU_EXPECT_NO_ERROR(gl.getError(), "Creating framebuffer");

    if (gl.checkFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
        throw tcu::NotSupportedError("Framebuffer is not complete");

    // Set up correct viewport for first test case.
    gl.viewport(0, 0, width, height);

    m_renderTarget = tcu::RenderTarget(width, height, pixelFormat, depthBits, stencilBits, config.numSamples);
}

void FboRenderContext::destroyFramebuffer(void)
{
    const glw::Functions &gl = m_context->getFunctions();

    if (m_framebuffer)
    {
        gl.deleteFramebuffers(1, &m_framebuffer);
        m_framebuffer = 0;
    }

    if (m_depthStencilBuffer)
    {
        gl.deleteRenderbuffers(1, &m_depthStencilBuffer);
        m_depthStencilBuffer = 0;
    }

    if (m_colorBuffer)
    {
        gl.deleteRenderbuffers(1, &m_colorBuffer);
        m_colorBuffer = 0;
    }
}

} // namespace glu