#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include "config.h"
#include "ge_color.h"
#include "entities/entities.h"

typedef struct {
    int score;
    ge_entity_t* player;
    ge_entity_t* bullets[MAX_BULLET];
    ge_render_rect_t screen;
    ge_entity_t* tilemap;
} game_ctx_t;

void collision_response(
    void* _ctx,
    ge_entity_t* entity_from, 
    ge_entity_t* entity_to,
    const ge_vector2i_t* vector // 反向推荐速度
) {
    game_ctx_t* ctx = _ctx;
    (void) ctx;
    (void) entity_to;
    // For box to box collision
    if (vector == NULL) return;
    
    switch (entity_from->user_type) {
    case PLAYER:
    case ENEMY:
        entity_from->position = vec2i_add(entity_from->position, *vector);
        break;
    case BULLET:
        entity_from->component_mask &= ~GE_COMPONENT_ACVIVE;
        break;
    default:
        break;
    }
}

void init(ge_core_t* core) {
    (void)core;

    static game_ctx_t ctx = { 0 };
    core->_systems.collision.ctx = &ctx;
    core->_systems.collision.callback = collision_response;

    init_tilemap(&core->ecs, &ctx.tilemap);
    init_player(&core->ecs, &ctx.player);
    for (int i = 0; i < MAX_BULLET; ++i) {
        init_bullet(&core->ecs, &ctx.bullets[i]);
    }

    ctx.screen = (ge_render_rect_t) {
        .pos = {0, 0},
        .size = core->_render.screen_size,
    };
    core->context = &ctx;
}

void process(ge_core_t* core) {
    game_ctx_t* ctx = (game_ctx_t*)core->context;
    core->_render.func_draw_rect(&core->_render, &ctx->screen, GE_COLOR_WHITE);
    ge_vector2i_t* player_pos = &ctx->player->position;
    ge_vector2i_t* player_vec = &ctx->player->physics_body.velocity;
    player_vec->x = 0;
    player_vec->y = 0;

    core->_render.func_draw_text(&core->_render, &ctx->screen, "Press 'p' to exit", player_pos, GE_COLOR_BLACK);
    ge_input_event_t key;
    if (!core->_input.func_recv(&core->_input, &key)) {
        switch (key.num) {
            case KEY_UP:
                MLOG_INFO(&logger, "KEY_UP");
                player_vec->y = - BASIC_SPEED;
                break;
            case KEY_DOWN:
                MLOG_INFO(&logger, "KEY_DOWN");
                player_vec->y = BASIC_SPEED;
                break;
            case KEY_LEFT:
                MLOG_INFO(&logger, "KEY_LEFT");
                player_vec->x = - BASIC_SPEED;
                break;
            case KEY_RIGHT:
                MLOG_INFO(&logger, "KEY_RIGHT");
                player_vec->x = BASIC_SPEED;
                break;
            case KEY_ATTACK:
                ge_entity_t* bullet = ctx->bullets[0];
                bullet->component_mask |= GE_COMPONENT_ACVIVE;
                bullet->position.x = player_pos->x + 4; // TODO
                bullet->position.y = player_pos->y; // TODO
                bullet->physics_body.velocity.x = 0;
                bullet->physics_body.velocity.y = - BASIC_SPEED / 2;
                break;
            case KEY_EXIT:
                core->state = GE_ENGINE_STATE_EXIT;
                MLOG_INFO(&logger, "exit");
                break;
        }
    }
}

int ge_main(ge_core_t* core) { 
    core->callbacks.init = init;
    core->callbacks.process = process;
    ge_engine_run(core);
    return 0;
}