#include "GPUFontAtlasLayerCombo.h"
#include "Utils.h"
#include "font.hpp"
#include "ofColor.h"
#include "ofEvents.h"
#include "ofGraphics.h"
#include "ofUtils.h"

namespace ofxVariableLab {

void GPUFontAtlasLayerCombo::setup(const ComboIdentifier & identifier,
                                   AtlasLayerComboSettings settings){
    this->identifier = identifier;
    this->settings = static_cast <GPUFontAtlasLayerComboSettings &>(settings);
    #ifdef TARGET_EMSCRIPTEN
        string shaderDir = "data/ofxGPUFont/shaders/DEBUG_ES3";
    #else
        string shaderDir = "data/ofxGPUFont/shaders/GL3";
    #endif
    shaderCatalog = std::make_unique <ofxGPUFont::ShaderCatalog>(shaderDir);
    //backgroundShader = shaderCatalog->get("background");
    fontShader = shaderCatalog->get("font");

    {
        FT_Error error = FT_Init_FreeType(&library);
        if(error){
            std::cerr << "ERROR: failed to initialize FreeType" << std::endl;
            ofExit();
        }
    }
    ofxGPUFont::tryUpdateMainFont(library,
                                  this->identifier.fontPath,
                                  mainText,
                                  font,
                                  this->settings.gpuTextureOffset);

    font->listFontVariationAxes(fontVariationAxesParameters, library);
    cout << this->identifier.fontPath << " : fontVariationAxes :" << endl;
    for(const auto & axis : fontVariationAxesParameters){
        cout << std::fixed << std::setprecision(10) << axis.name << " :\n"
             << "\tmin: " << std::to_string(axis.minValue)
             << "\tmax: " << std::to_string(axis.maxValue)
             << "\tdefault: " << std::to_string(axis.defaultValue) << endl;
        fontVariationAxes.push_back({axis.name, axis.defaultValue});
    }

    transform = Transform();

    auto & r = ofGetCurrentRenderer();
    cout << "Render type " << r->getType() << endl;
}
void GPUFontAtlasLayerCombo::update(){
    //float animationSpeed = 1.0;
    //float threshold = 1.0;
    //for(int i = 0; i < fontVariationAxes.size(); i++){
    //ofxGPUFont::Font::FontVariationAxis & axis = fontVariationAxes[i];
    //ofxGPUFont::Font::FontVariationAxisParameters & axisParams = fontVariationAxesParameters[i];
    //double newValue = ofMap(sin(ofGetElapsedTimef() * animationSpeed),
    //-1, 1,
    //axisParams.minValue, axisParams.maxValue);
    //if(abs(newValue - axis.value) > threshold){
    //font->setFontVariationAxis(library, axis.name, newValue);
    //axis.value = newValue;
    //font->prepareGlyphsForText(mainText, true);
    //}
    //}
    if(isDirty){
        //ofxGPUFont::tryUpdateMainFont(library,
        //this->identifier.fontPath,
        //mainText,
        //font,
        //this->settings.gpuTextureOffset);
        font->prepareGlyphsForText(mainText, true);
        isDirty = false;
    }
}
void GPUFontAtlasLayerCombo::careForChild(shared_ptr <Layer> layer){
    if(layer->getType() == Layer::GPUFONT){
        shared_ptr <GPUFontLayer> gpuFontLayer = static_pointer_cast <GPUFontLayer>(layer);
        layers.push_back(gpuFontLayer);
        std::string oldText = mainText;
        std::string layerText = gpuFontLayer->getProps().text;
        std::string text = oldText + layerText;
        totalCharacters += layerText.length();
        removeDuplicateCharacters(text);
        // check if we added any characters
        // TODO: check for variation variations
        if(text.length() != oldText.length()){
            mainText = text;
            isDirty = true;
        }
    }else{
        ofLogError("GPUFontAtlasLayerCombo::careForChild()") << __LINE__ << ": child is not recognized as Layer::GPUFONT";
    }
}
void GPUFontAtlasLayerCombo::abandonChild(shared_ptr <Layer> layer){
    // TODO: handle removing child text from buffer
    shared_ptr <GPUFontLayer> gpuFontLayer = static_pointer_cast <GPUFontLayer>(layer);
    layers.erase(
        std::remove_if(
            layers.begin(),
            layers.end(),
            [gpuFontLayer](shared_ptr <GPUFontLayer> const & l)
        {
            return l == gpuFontLayer;
        }), layers.end());

    // update the text
    // this doesn't happen very often, so let's just
    // iterate over all layers and calculate fresh
    std::string text = "";
    totalCharacters = 0;
    for(const auto & layer : layers){
        std::string layerText = layer->getProps().text;
        totalCharacters += layerText.length();
        text += layerText;
    }
    removeDuplicateCharacters(text);
    mainText = text;
    // NOTE: we do not want to update buffers now,
    // as it's probably more costly than just keeping
    // the old glyphs around...
}
const ComboIdentifier & GPUFontAtlasLayerCombo::getIdentifier() const {
    return identifier;
}
void GPUFontAtlasLayerCombo::setVFlip(VFlipState vFlipState){
    vFlip = vFlipState;
}
const vector <shared_ptr <GPUFontLayer> > & GPUFontAtlasLayerCombo::getLayers(){
    return layers;
}
void GPUFontAtlasLayerCombo::draw(){
    GLuint location;

    int width = ofGetWidth();
    int height = ofGetHeight();
    glm::vec2 mouse = glm::vec2(ofGetMouseX(), ofGetMouseY());

    //glm::mat4 projection = transform.getProjectionMatrix((float)width / height);
    glm::mat4 projection = transform.getOrthoProjectionMatrix(width,
                                                              height,
                                                              Transform::TOP_LEFT);
    //Transform::CENTERED);
    glm::mat4 view = transform.getViewMatrix();
    glm::mat4 model = glm::mat4(1.0f);

    //{     // Draw background.
    //GLuint program = backgroundShader->program;
    //glUseProgram(program);
    //glBindVertexArray(emptyVAO);
    //glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
    //glBindVertexArray(0);
    //glUseProgram(0);
    //}

    // Uses premultiplied-alpha.
    glEnable(GL_BLEND);
    glBlendEquation(GL_FUNC_ADD);
    glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
    ofDisableDepthTest();
    ofEnableAlphaBlending();

    int currentProgram;
    glGetIntegerv(GL_CURRENT_PROGRAM, &currentProgram);

    float cx = FLT_MAX;
    float cy = FLT_MAX;
    if(font){
        fontShaderProgram = fontShader->program;
        glUseProgram(fontShaderProgram);

        font->program = fontShaderProgram;
        font->drawSetup();

        location = glGetUniformLocation(fontShaderProgram, "projection");
        glUniformMatrix4fv(location, 1, false, glm::value_ptr(projection));

        location = glGetUniformLocation(fontShaderProgram, "view");
        glUniformMatrix4fv(location, 1, false, glm::value_ptr(view));
        location = glGetUniformLocation(fontShaderProgram, "model");
        glUniformMatrix4fv(location, 1, false, glm::value_ptr(model));
        float z = 0;
        location = glGetUniformLocation(fontShaderProgram, "z");
        glUniform1f(location, z);

        location = glGetUniformLocation(fontShaderProgram, "color");
        glUniform4f(location, 1.0f, 1.0f, 1.0f, 0.5f);

        location = glGetUniformLocation(fontShaderProgram, "antiAliasingWindowSize");
        glUniform1f(location, (float)antiAliasingWindowSize);
        location = glGetUniformLocation(fontShaderProgram, "enableSuperSamplingAntiAliasing");
        glUniform1i(location, enableSuperSamplingAntiAliasing);
        location = glGetUniformLocation(fontShaderProgram, "enableControlPointsVisualization");
        glUniform1i(location, enableControlPointsVisualization);


        //mouse.x = 0;
        //mouse.y = 0;
        std::vector <ofxGPUFont::Font::BufferVertex> vertices;
        std::vector <int32_t> indices;

        for(const auto & layer : layers){
            font->collectVerticesAndIndices(glm::vec3(layer->getProps().x,
                                                      layer->getProps().y,
                                                      0),
                                            layer->getProps().text,
                                            vertices, indices, true,
                                            layer->getProps().fontSize_px);
        }
        vertices.resize(totalCharacters * 4);
        indices.resize(totalCharacters * 6);
        //cx = 0.5f * (bb.minX + bb.maxX);
        //cy = 0.5f * (bb.minY + bb.maxY);

        font->draw(vertices, indices);
        //ofRectangle rectangle(0, 0, width, height);
        //ofDrawRectangle(rectangle);
        //font->draw(mouse.x, mouse.y - (200 * sin(ofGetElapsedTimef() * 0.25)), 0, "what", vFlip == V_FLIP_ON, 42.0f);
        //location = glGetUniformLocation(fontShaderProgram, "color");
        //glUniform4f(location, 0.0f, 1.0f, 0.0f, 0.5f);
        //font->draw(mouse.x, mouse.y, 0, "ever", vFlip == V_FLIP_ON, 420.0f);

        glUseProgram(currentProgram);
    }

    glDisable(GL_BLEND);

    //ofDrawBitmapStringHighlight(
    //(ofToString("and we know:") + ofToString("everything"))
    //, 100 + mouse.x, mouse.y, ofFloatColor::pink, ofFloatColor::black);

    ofDrawBitmapStringHighlight(
        "fps: " + ofToString(ofGetFrameRate()) + "\n"
        + "font: " + this->identifier.fontPath + "\n"
        , 20, 20);
}

}