/*
* Copyright (C) 2011 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.
*/
#include "ColorBuffer.h"
#include "FrameBuffer.h"
#include "EGLDispatch.h"
#include "GLDispatch.h"
#include "ThreadInfo.h"
#ifdef WITH_GLES2
#include "GL2Dispatch.h"
#endif
#include <stdio.h>

ColorBuffer *ColorBuffer::create(int p_width, int p_height,
                                 GLenum p_internalFormat)
{
    FrameBuffer *fb = FrameBuffer::getFB();

    GLenum texInternalFormat = 0;

    switch(p_internalFormat) {
        case GL_RGB:
        case GL_RGB565_OES:
            texInternalFormat = GL_RGB;
            break;

        case GL_RGBA:
        case GL_RGB5_A1_OES:
        case GL_RGBA4_OES:
            texInternalFormat = GL_RGBA;
            break;

        default:
            return NULL;
            break;
    }

    if (!fb->bind_locked()) {
        return NULL;
    }

    ColorBuffer *cb = new ColorBuffer();


    s_gl.glGenTextures(1, &cb->m_tex);
    s_gl.glBindTexture(GL_TEXTURE_2D, cb->m_tex);
    s_gl.glTexImage2D(GL_TEXTURE_2D, 0, texInternalFormat,
                      p_width, p_height, 0,
                      texInternalFormat,
                      GL_UNSIGNED_BYTE, NULL);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    s_gl.glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

    cb->m_width = p_width;
    cb->m_height = p_height;

    if (fb->getCaps().has_eglimage_texture_2d) {
        cb->m_eglImage = s_egl.eglCreateImageKHR(fb->getDisplay(),
                                                 fb->getContext(),
                                                 EGL_GL_TEXTURE_2D_KHR,
                                                 (EGLClientBuffer)cb->m_tex,
                                                 NULL);
    }

    fb->unbind_locked();
    return cb;
}

ColorBuffer::ColorBuffer() :
    m_tex(0),
    m_eglImage(NULL),
    m_fbo(0)
{
}

ColorBuffer::~ColorBuffer()
{
    FrameBuffer *fb = FrameBuffer::getFB();
    fb->bind_locked();
    s_gl.glDeleteTextures(1, &m_tex);
    if (m_eglImage) {
        s_egl.eglDestroyImageKHR(fb->getDisplay(), m_eglImage);
    }
    if (m_fbo) {
        s_gl.glDeleteFramebuffersOES(1, &m_fbo);
    }
    fb->unbind_locked();
}

void ColorBuffer::update(GLenum p_format, GLenum p_type, void *pixels)
{
    FrameBuffer *fb = FrameBuffer::getFB();
    if (!fb->bind_locked()) return;
    s_gl.glBindTexture(GL_TEXTURE_2D, m_tex);
    s_gl.glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    s_gl.glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
                         m_width, m_height, p_format, p_type, pixels);
    fb->unbind_locked();
}

void ColorBuffer::subUpdate(int x, int y, int width, int height, GLenum p_format, GLenum p_type, void *pixels)
{
    FrameBuffer *fb = FrameBuffer::getFB();
    if (!fb->bind_locked()) return;
    s_gl.glBindTexture(GL_TEXTURE_2D, m_tex);
    s_gl.glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    s_gl.glTexSubImage2D(GL_TEXTURE_2D, 0, x, y,
                         width, height, p_format, p_type, pixels);
    fb->unbind_locked();
}

bool ColorBuffer::blitFromPbuffer(EGLSurface p_pbufSurface)
{
    FrameBuffer *fb = FrameBuffer::getFB();
    if (!fb->bind_locked()) return false;

    //
    // bind FBO object which has this colorbuffer as render target
    //
    if (!bind_fbo()) {
        fb->unbind_locked();
        return false;
    }

    //
    // bind the pbuffer to a temporary texture object
    //
    GLuint tempTex;
    s_gl.glGenTextures(1, &tempTex);
    s_gl.glBindTexture(GL_TEXTURE_2D, tempTex);
    if (!s_egl.eglBindTexImage(fb->getDisplay(), p_pbufSurface, EGL_BACK_BUFFER)) {
        printf("eglBindTexImage failed 0x%x\n", s_egl.eglGetError());
        s_gl.glDeleteTextures(1, &tempTex);
        fb->unbind_locked();
        return false;
    }

    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    s_gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    s_gl.glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
    s_gl.glEnable(GL_TEXTURE_2D);

    drawTexQuad();

    //
    // unbind FBO, release the pbuffer and delete the temp texture object
    //
    s_gl.glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0);
    s_egl.eglReleaseTexImage(fb->getDisplay(), p_pbufSurface, EGL_BACK_BUFFER);
    s_gl.glDeleteTextures(1, &tempTex);

    fb->unbind_locked();
    return true;
}

bool ColorBuffer::bindToTexture()
{
    if (m_eglImage) {
        RenderThreadInfo *tInfo = getRenderThreadInfo();
        if (tInfo->currContext.Ptr()) {
#ifdef WITH_GLES2
            if (tInfo->currContext->isGL2()) {
                s_gl2.glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, m_eglImage);
            }
            else {
                s_gl.glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, m_eglImage);
            }
#else
            s_gl.glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, m_eglImage);
#endif
            return true;
        }
    }
    return false;
}

bool ColorBuffer::bind_fbo()
{
    if (m_fbo) {
        // fbo already exist - just bind
        s_gl.glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_fbo);
        return true;
    }

    s_gl.glGenFramebuffersOES(1, &m_fbo);
    s_gl.glBindFramebufferOES(GL_FRAMEBUFFER_OES, m_fbo);
    s_gl.glFramebufferTexture2DOES(GL_FRAMEBUFFER_OES,
                                   GL_COLOR_ATTACHMENT0_OES,
                                   GL_TEXTURE_2D, m_tex, 0);
    GLenum status = s_gl.glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES);
    if (status != GL_FRAMEBUFFER_COMPLETE_OES) {
        s_gl.glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0);
        s_gl.glDeleteFramebuffersOES(1, &m_fbo);
        m_fbo = 0;
        return false;
    }

    return true;
}

bool ColorBuffer::post()
{
    s_gl.glBindTexture(GL_TEXTURE_2D, m_tex);
    s_gl.glEnable(GL_TEXTURE_2D);
    drawTexQuad();

    return true;
}

void ColorBuffer::drawTexQuad()
{
    GLfloat verts[] = { -1.0f, -1.0f, 0.0f,
                         -1.0f, +1.0f, 0.0f,
                         +1.0f, -1.0f, 0.0f,
                         +1.0f, +1.0f, 0.0f };

    GLfloat tcoords[] = { 0.0f, 0.0f,
                           0.0f, 1.0f,
                           1.0f, 0.0f,
                           1.0f, 1.0f };

    s_gl.glClientActiveTexture(GL_TEXTURE0);
    s_gl.glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    s_gl.glTexCoordPointer(2, GL_FLOAT, 0, tcoords);

    s_gl.glEnableClientState(GL_VERTEX_ARRAY);
    s_gl.glVertexPointer(3, GL_FLOAT, 0, verts);
    s_gl.glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
}