/*
 * Copyright (c) 2010-2012 OTClient <https://github.com/edubart/otclient>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "paintershaderprogram.h"
#include "painter.h"
#include "texture.h"
#include "texturemanager.h"
#include <framework/core/clock.h>

PainterShaderProgram::PainterShaderProgram()
{
    m_startTime = g_clock.time();
    m_opacity = 1;
    m_color = Color::white;
    m_time = 0;
    m_lastTexture = -1;
    m_textures.fill(0);
}

bool PainterShaderProgram::link()
{
    m_startTime = g_clock.time();
    bindAttributeLocation(VERTEX_ATTR, "a_vertex");
    bindAttributeLocation(TEXCOORD_ATTR, "a_texCoord");
    if(ShaderProgram::link()) {
        bindUniformLocation(PROJECTION_MATRIX_UNIFORM, "projectionMatrix");
        bindUniformLocation(TEXTURE_TRANSFORM_MATRIX_UNIFORM, "texTransformMatrix");
        bindUniformLocation(COLOR_UNIFORM, "color");
        bindUniformLocation(OPACITY_UNIFORM, "opacity");
        bindUniformLocation(TIME_UNIFORM, "time");
        bindUniformLocation(TEX0_UNIFORM, "tex0");
        bindUniformLocation(TEX1_UNIFORM, "tex1");

        bind();
        setUniformValue(PROJECTION_MATRIX_UNIFORM, m_projectionMatrix);
        setUniformValue(TEXTURE_TRANSFORM_MATRIX_UNIFORM, m_textureTransformMatrix);
        setUniformValue(COLOR_UNIFORM, m_color);
        setUniformValue(OPACITY_UNIFORM, m_opacity);
        setUniformValue(TIME_UNIFORM, m_time);
        setUniformValue(TEX0_UNIFORM, 0);
        setUniformValue(TEX1_UNIFORM, 1);

        enableAttributeArray(PainterShaderProgram::VERTEX_ATTR);
        enableAttributeArray(PainterShaderProgram::TEXCOORD_ATTR);
        return true;
    }
    return false;
}

void PainterShaderProgram::setProjectionMatrix(const Matrix3& projectionMatrix)
{
    if(projectionMatrix == m_projectionMatrix)
        return;

    bind();
    setUniformValue(PROJECTION_MATRIX_UNIFORM, projectionMatrix);
    m_projectionMatrix = projectionMatrix;
}

void PainterShaderProgram::setColor(const Color& color)
{
    if(color == m_color)
        return;

    bind();
    setUniformValue(COLOR_UNIFORM, color);
    m_color = color;
}

void PainterShaderProgram::setOpacity(float opacity)
{
    if(m_opacity == opacity)
        return;

    bind();
    setUniformValue(OPACITY_UNIFORM, opacity);
    m_opacity = opacity;
}

void PainterShaderProgram::setTexture(const TexturePtr& texture, int index)
{
    assert(index >= 0 && index <= 1);

    uint texId = texture ? texture->getId() : 0;

    if(m_textures[index] == texId)
        return;

    m_textures[index] = texId;
    m_lastTexture = std::max(m_lastTexture, index);

    if(texture && index == 0) {
        const Matrix2& textureTransformMatrix = texture->getTransformMatrix();
        if(m_textureTransformMatrix != textureTransformMatrix) {
            bind();
            setUniformValue(TEXTURE_TRANSFORM_MATRIX_UNIFORM, textureTransformMatrix);
            m_textureTransformMatrix = textureTransformMatrix;
        }
    }
}

void PainterShaderProgram::draw(CoordsBuffer& coordsBuffer, DrawMode drawMode)
{
    bind();

    float time = g_clock.timeElapsed(m_startTime);
    if(m_time != time) {
        setUniformValue(TIME_UNIFORM, time);
        m_time = time;
    }

    int vertexCount = coordsBuffer.getVertexCount();
    if(vertexCount == 0)
        return;

    coordsBuffer.updateCaches();
    bool hardwareCached = coordsBuffer.isHardwareCached();

    if(hardwareCached)
        coordsBuffer.getHardwareVertexBuffer()->bind();
    setAttributeArray(PainterShaderProgram::VERTEX_ATTR, hardwareCached ? 0 : coordsBuffer.getVertexBuffer(), 2);

    bool hasTexture = coordsBuffer.getTextureVertexCount() != 0;
    if(hasTexture) {
        if(hardwareCached)
            coordsBuffer.getHardwareTextureVertexBuffer()->bind();
        setAttributeArray(PainterShaderProgram::TEXCOORD_ATTR, hardwareCached ? 0 : coordsBuffer.getTextureVertexBuffer(), 2);
    }

    if(hardwareCached)
        HardwareBuffer::unbind(HardwareBuffer::VertexBuffer);

    if(m_lastTexture == 0) {
        glBindTexture(GL_TEXTURE_2D, m_textures[0]);
    } else {
        glActiveTexture(GL_TEXTURE1);
        glBindTexture(GL_TEXTURE_2D, m_textures[1]);
        glActiveTexture(GL_TEXTURE0);
        glBindTexture(GL_TEXTURE_2D, m_textures[0]);
    }

    glDrawArrays(drawMode, 0, vertexCount);
}