#include "renderer_polygon_3d.hpp"

#include <iostream>

#include "glm/gtc/type_ptr.hpp"

#include "polygon_model.hpp"

namespace endofthejedi {
    void RendererPolygon3d::setup()
    {
        std::cout<<"setup polygon 3d" << std::endl;

        //m_missileModel = new PolygonModel("../data/mesh/quad_screen_coords.stl");

        addModel("../data/mesh/small_atomic_bomb.stl", &m_missileModel);
        //addModel("../data/mesh/planet_128.stl",        &m_planetModel);
        addModel("../data/mesh/planet_12.stl",         &m_planetModel);
        addModel("../data/mesh/ship.stl",              &m_shipModel);

        std::string vss_simple =
            "#version 120\n"
            "varying vec3 vertex;\n"
            "void main()\n"
            "{\n"
            "  gl_Position = gl_Vertex;\n"
            "  vertex = gl_Position.xyz;\n"
            "}\n"
            ;

        std::string fss_simple =
            "#version 120\n"
            "varying vec3 vertex;\n"
            "void main()\n"
            "{\n"
            //"  gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);\n"
            "  gl_FragColor = vec4(0.5+0.5*vertex.xyz, 1.0);\n"
            "}\n"
            ;

        std::string vss_game_objects =
            "#version 120\n"
            "uniform vec3 position;\n"
            "uniform float scale;\n"
            "varying vec3 vertex;\n"
            "void main()\n"
            "{\n"
            "  vec3 p = scale*gl_Vertex.xyz;\n"
            "  p += position;\n"
            "  gl_Position = vec4(p, gl_Vertex.w);\n"
            "  vertex = p;\n"
            "}\n"
            ;

        std::string fss_game_objects =
            "#version 120\n"
            "varying vec3 vertex;\n"
            "uniform vec3 color;\n"
            "void main()\n"
            "{\n"
            //"  gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);\n"
            //"  gl_FragColor = vec4(0.5+0.5*vertex.xyz, 1.0);\n"
            "  gl_FragColor = vec4(color, 1.0);\n"
            "}\n"
            ;

        m_shader.init();

#if 0
        (void) vss_game_objects;
        (void) fss_game_objects;
        m_shader.load(vss_simple.c_str(), GL_VERTEX_SHADER);
        m_shader.load(fss_simple.c_str(), GL_FRAGMENT_SHADER);
#else
        (void) vss_simple;
        (void) fss_simple;
        m_shader.load(vss_game_objects.c_str(), GL_VERTEX_SHADER);
        m_shader.load(fss_game_objects.c_str(), GL_FRAGMENT_SHADER);
#endif
    }

    void RendererPolygon3d::render(const game::State *state)
    {
        m_shader.bind();

        // TODO :Z?

        renderPlanets(state);
        renderShips(state);
        renderMissiles(state);


        //glColor3f(1.0, 0.0, 0.0);
        //glBegin(GL_QUADS);
        //glVertex2f(-1.0f, -1.0f);
        //glVertex2f(1.0f, -1.0f);
        //glVertex2f(1.0f, 1.0f);
        //glVertex2f(-1.0f, 1.0f);
        //glEnd();
    }

    void RendererPolygon3d::renderPlanets(const game::State *state)
    {
        m_planetModel->bind();

        for (const game::Planet *planet : state->planets) {
            glm::vec3 c = glm::vec3(0.7, 0.2, 0.1);
            const auto &p = planet->position;

            glUniform3f(m_shader.location("position"), p.x, p.y, 0.0);
            glUniform3f(m_shader.location("color"),    c.x, c.y, c.z);
            glUniform1f(m_shader.location("scale"),    planet->radius);

            m_planetModel->render();
        }
    }

    void RendererPolygon3d::renderMissiles(const game::State *state)
    {
        m_missileModel->bind();

        for (const game::Player *player : state->players) {
            for (const game::Missile *missile : player->missiles) {
                glm::vec3 c = glm::vec3(1.0, 1.0, 0.3);
                const auto &p = missile->position;

                glUniform3f(m_shader.location("position"), p.x, p.y, 0.0);
                glUniform3f(m_shader.location("color"),    c.x, c.y, c.z);
                glUniform1f(m_shader.location("scale"),    1.0);

                m_missileModel->render();
            }
        }
    }

    void RendererPolygon3d::renderShips(const game::State *state)
    {
        m_shipModel->bind();

        for (const game::Ship *ship : state->ships) {
            glm::vec3 c = glm::vec3(0.1, 1.0, 0.2);
            const auto &p = ship->position;

            glUniform3f(m_shader.location("position"), p.x, p.y, 0.0);
            glUniform3f(m_shader.location("color"),    c.x, c.y, c.z);
            glUniform1f(m_shader.location("scale"),    0.02);

            m_shipModel->render();
        }
    }

    void RendererPolygon3d::addModel(const std::string &filename, PolygonModel **dest)
    {
        std::cout<<"adding a model: " << filename << std::endl;

        *dest = new PolygonModel(filename);
        if (!(*dest)->import()) {
            std::cout<<"error: failed to load needed model!!!" << std::endl << std::endl;
            exit(-1);
        }

        (*dest)->uploadToOpenGl();

        m_models.push_back(*dest);
    }
}