module zelda.ApplicationWindow;

import std.string;

import derelict.opengl3.gl;

import derelict.sdl2.sdl;

class ApplicationWindow {
    this() {
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);

        m_width = 160 * 3;
        m_height = 144 * 3;

        m_window = SDL_CreateWindow("DZelda", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, m_width, m_height, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN);
        if(!m_window) {
            throw new Exception(
                format("Error while initializing window: %s", SDL_GetError()));
        }

        m_context = SDL_GL_CreateContext(m_window);
        if(!m_context) {
            throw new Exception(
                format("Error while initializing OpenGL context: %s", SDL_GetError()));
        }

        DerelictGL.reload();

        initOpenGL();

        m_isOpen = true;
    }

    ~this() {
        SDL_DestroyWindow(m_window);
        SDL_GL_DeleteContext(m_context);
    }

    void initOpenGL() {
        glEnable(GL_BLEND);
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

        glEnable(GL_TEXTURE_2D);
    }

    void clear() {
        glClear(GL_COLOR_BUFFER_BIT);
    }

    void update() {
        SDL_GL_SwapWindow(m_window);
    }

    bool isOpen() const { return m_isOpen; }
    void close() { m_isOpen = false; }

    private SDL_Window *m_window;
    private SDL_GLContext m_context;

    private bool m_isOpen = false;

    private ushort m_width = 0;
    private ushort m_height = 0;
}