#include <stdio.h>
#include <string.h>
#include <mgl/mgl.h>
#include <mgl/window/window.h>
#include <mgl/window/event.h>
#include <mgl/graphics/texture.h>
#include <mgl/graphics/rectangle.h>
#include <mgl/graphics/sprite.h>
#include <mgl/graphics/font.h>
#include <mgl/graphics/text.h>
#include <mgl/graphics/vertex_buffer.h>
#include <mgl/graphics/shader.h>
#include <mgl/system/clock.h>

typedef struct {
    mgl_texture *texture;
    mgl_font *font;
    mgl_font *cjk_font;
    mgl_vertex_buffer *vertex_buffer1;
    mgl_vertex_buffer *vertex_buffer2;
    mgl_shader_program *shader_program;
    mgl_clock clock;
    int fps;
    int fps_counter;
} Userdata;

static void draw(mgl_window *window, void *userdata) {
    mgl_context *context = mgl_get_context();
    Userdata *u = userdata;

    mgl_rectangle rect = {
        .color = { 255, 0, 0, 255 },
        .position = { window->cursor_position.x, window->cursor_position.y },
        .size = { 100.0f, 500.0f }
    };
    mgl_rectangle_draw(context, &rect);

    mgl_shader_program_set_uniform_vec2f(u->shader_program, "resolution", (mgl_vec2f){ u->texture->width, u->texture->height });

    mgl_sprite sprite;
    mgl_sprite_init(&sprite, u->texture, 100.0f - 10.0f, 0.0f);
    mgl_sprite_set_color(&sprite, (mgl_color){255, 255, 255, 128});
    mgl_shader_program_use(u->shader_program);
    mgl_sprite_draw(context, &sprite);
    mgl_shader_program_use(NULL);

    ++u->fps_counter;
    if(mgl_clock_get_elapsed_time_seconds(&u->clock) >= 1.0) {
        mgl_clock_restart(&u->clock);
        u->fps = u->fps_counter;
        u->fps_counter = 0;
    }
    char str[255];
    snprintf(str, sizeof(str), "hello|world\nfps: %d", u->fps);

    mgl_text text;
    mgl_text_init(&text, u->font, str, strlen(str));
    mgl_text_draw(context, &text);
    mgl_text_deinit(&text);

    const char *cjk_str = "一丏";

    mgl_text cjk_text;
    mgl_text_init(&cjk_text, u->cjk_font, cjk_str, strlen(cjk_str));
    mgl_text_set_position(&cjk_text, (mgl_vec2f){ 0.0f, 500.0f });
    mgl_text_draw(context, &cjk_text);
    mgl_text_deinit(&cjk_text);

    mgl_vertex_buffer_set_position(u->vertex_buffer1, (mgl_vec2f){ window->cursor_position.x, window->cursor_position.y });
    mgl_vertex_buffer_draw(context, u->vertex_buffer1, &u->font->texture);

    mgl_vertex_buffer_set_position(u->vertex_buffer2, (mgl_vec2f){ window->cursor_position.x, window->cursor_position.y + 500 });
    mgl_vertex_buffer_draw(context, u->vertex_buffer2, &u->font->texture);

    mgl_view prev_view;
    mgl_window_get_view(window, &prev_view);

    mgl_vec2i view_size = {
        .x = 200,
        .y = 200
    };
    mgl_view new_view = {
        .position = { window->size.x/2 - view_size.x/2, window->size.y/2 - view_size.y/2 },
        .size = view_size
    };
    mgl_window_set_view(window, &new_view);

    mgl_vertex vertices[4] = {
        (mgl_vertex){
            .position = {-new_view.position.x + window->cursor_position.x, -new_view.position.y + window->cursor_position.y},
            .texcoords = {0.0f, 0.0f},
            .color = {255, 0, 0, 255}
        },
        (mgl_vertex){
            .position = {-new_view.position.x + window->cursor_position.x + 400.0f, -new_view.position.y + window->cursor_position.y},
            .texcoords = {0.0f, 0.0f},
            .color = {0, 255, 0, 255},
        },
        (mgl_vertex){
            .position = {-new_view.position.x + window->cursor_position.x + 400.0f, -new_view.position.y + window->cursor_position.y + 400.0f},
            .texcoords = {0.0f, 0.0f},
            .color = {0, 0, 255, 255},
        },
        (mgl_vertex){
            .position = {-new_view.position.x + window->cursor_position.x, -new_view.position.y + window->cursor_position.y + 400.0f},
            .texcoords = {0.0f, 0.0f},
            .color = {255, 255, 0, 255}
        }
    };

    mgl_vertices_draw(context, vertices, 4, MGL_PRIMITIVE_QUADS);
    mgl_window_set_view(window, &prev_view);
}

int main(int argc, char **argv) {
    if(mgl_init() != 0)
        return 1;

    mgl_texture texture;
    mgl_font font;
    mgl_font cjk_font;
    mgl_vertex_buffer vertex_buffer1;
    mgl_vertex_buffer vertex_buffer2;
    mgl_shader_program shader_program;

    Userdata userdata;
    userdata.texture = &texture;
    userdata.font = &font;
    userdata.cjk_font = &cjk_font;
    userdata.vertex_buffer1 = &vertex_buffer1;
    userdata.vertex_buffer2 = &vertex_buffer2;
    userdata.shader_program = &shader_program;
    userdata.fps = 0;
    userdata.fps_counter = 0;
    mgl_clock_init(&userdata.clock);

    mgl_window window;
    if(mgl_window_create(&window, "mgl", 1280, 720) != 0)
        return 1;

    if(mgl_texture_load_from_file(&texture, "tests/X11.jpg", NULL) != 0)
        return 1;

    if(mgl_font_load_from_file(&font, "/usr/share/fonts/noto/NotoSans-Regular.ttf", 32) != 0)
        return 1;

    if(mgl_font_load_from_file(&cjk_font, "/usr/share/fonts/noto-cjk/NotoSansCJK-Regular.ttc", 32) != 0)
        return 1;

    if(mgl_shader_program_init(&shader_program) != 0)
        return 1;

    if(mgl_shader_program_add_shader_from_file(&shader_program, "tests/circle_mask.glsl", MGL_SHADER_FRAGMENT) != 0)
        return 1;

    if(mgl_shader_program_finalize(&shader_program) != 0)
        return 1;

    mgl_vertex_buffer_init(&vertex_buffer1);
    mgl_vertex_buffer_init(&vertex_buffer2);

    mgl_vertex vertices1[4] = {
        (mgl_vertex){
            .position = {0.0f, 0.0f},
            .texcoords = {0.0f, 0.0f},
            .color = {255, 0, 0, 100}
        },
        (mgl_vertex){
            .position = {font.texture.width, 0.0f},
            .texcoords = {1.0f, 0.0f},
            .color = {0, 255, 0, 100},
        },
        (mgl_vertex){
            .position = {font.texture.width, font.texture.height/2},
            .texcoords = {1.0f, 0.5f},
            .color = {0, 0, 255, 100},
        },
        (mgl_vertex){
            .position = {0.0f, font.texture.height/2},
            .texcoords = {0.0f, 0.5f},
            .color = {255, 0, 255, 100}
        }
    };

    mgl_vertex vertices2[4] = {
        (mgl_vertex){
            .position = {0.0f, 0.0f},
            .texcoords = {0.0f, 0.5f},
            .color = {255, 0, 0, 100}
        },
        (mgl_vertex){
            .position = {font.texture.width, 0.0f},
            .texcoords = {1.0f, 0.5f},
            .color = {0, 255, 0, 100},
        },
        (mgl_vertex){
            .position = {font.texture.width, font.texture.height/2},
            .texcoords = {1.0f, 1.0f},
            .color = {0, 0, 255, 100},
        },
        (mgl_vertex){
            .position = {0.0f, font.texture.height/2},
            .texcoords = {0.0f, 1.0f},
            .color = {255, 0, 255, 100}
        }
    };

    if(mgl_vertex_buffer_update(&vertex_buffer1, vertices1, 4, MGL_PRIMITIVE_QUADS, MGL_USAGE_STATIC) != 0)
        return 1;

    if(mgl_vertex_buffer_update(&vertex_buffer2, vertices2, 4, MGL_PRIMITIVE_QUADS, MGL_USAGE_STATIC) != 0)
        return 1;

    fprintf(stderr, "Font texture width: %d, texture height: %d\n", font.texture.width, font.texture.height);

    mgl_event event;
    while(mgl_window_is_open(&window)) {
        while(mgl_window_poll_event(&window, &event)) {
            switch(event.type) {
                case MGL_EVENT_TEXT_ENTERED: {
                    fprintf(stderr, "text event, codepoint: %u\n", event.text.codepoint);
                    break;
                }
                case MGL_EVENT_KEY_PRESSED: {
                    fprintf(stderr, "key press event, code: %u\n", event.key.code);
                    break;
                }
                case MGL_EVENT_KEY_RELEASED: {
                    fprintf(stderr, "key release event, code: %u\n", event.key.code);
                    break;
                }
            }
        }

        mgl_window_clear(&window, (mgl_color){0, 0, 0, 255});
        draw(&window, &userdata);
        mgl_window_display(&window);
    }

    mgl_vertex_buffer_deinit(&vertex_buffer2);
    mgl_vertex_buffer_deinit(&vertex_buffer1);
    mgl_shader_program_deinit(&shader_program);
    mgl_font_unload(&font);
    mgl_texture_unload(&texture);
    mgl_window_deinit(&window);
    mgl_deinit();
    return 0;
}