#include "games/pong/Pong.hpp"
#include "games/Game.hpp"
#include "common/shapes.hpp"
#include "renderer/Renderer.hpp"


void
Pong::Start()
{
    m_paddles[0].dir = NONE;
    m_paddles[0].y = 1.5f;

    m_paddles[1].dir = NONE;
    m_paddles[1].y = 1.5f;

    m_ball.circle.x = 2.0f;
    m_ball.circle.y = 1.5f;
    m_ball.circle.r = 0.1f;

    m_ball.velocity.x = 1.0f;
    m_ball.velocity.y = 0.0f;

    m_game_status = game_resume;
}

void
Pong::ProcessEvent(SDL_Event& event)
{
    switch (event.type) {
    case SDL_EVENT_KEY_DOWN: {
        auto key = event.key.key;
        if (key == SDLK_ESCAPE) {
            m_game_status = game_pause;
        }
        else if (key == SDLK_W) {
            m_paddles[0].dir = UP;
        }
        else if (key == SDLK_S) {
            m_paddles[0].dir = DOWN;
        }
        else if (key == SDLK_UP) {
            m_paddles[1].dir = UP;
        }
        else if (key == SDLK_DOWN) {
            m_paddles[1].dir = DOWN;
        }
    } break;

    case SDL_EVENT_KEY_UP: {
        auto key = event.key.key;
        if (key == SDLK_W && m_paddles[0].dir == UP) {
            m_paddles[0].dir = NONE;
        }
        else if (key == SDLK_S && m_paddles[0].dir == DOWN) {
            m_paddles[0].dir = NONE;
        }
        else if (key == SDLK_UP && m_paddles[1].dir == UP) {
            m_paddles[1].dir = NONE;
        }
        else if (key == SDLK_DOWN && m_paddles[1].dir == DOWN) {
            m_paddles[1].dir = NONE;
        }
    } break;

    default:;
    }
}

void
Pong::FinishUpdate(float dt)
{
    MoveBall(dt);
    MovePaddle(m_paddles[0], dt);
    MovePaddle(m_paddles[1], dt);
}

void
Pong::MovePaddle(Paddle& paddle, float dt)
{
    if (paddle.dir) {
        paddle.y += (float)paddle.dir * (PADDLE_SPEED * dt);
    }

    if (paddle.y <= 0.0f) {
        paddle.y = 0.0f;
    }
    if (paddle.y + PADDLE_HEIGHT > 3.0f) {
        paddle.y = 3.0f - PADDLE_HEIGHT;
    }
}

void
Pong::MoveBall(float dt)
{
    // Todo: do physics! find trajectories, find intersection, bounce off properly

    m_ball.circle.x += m_ball.velocity.x * dt;
    m_ball.circle.y += m_ball.velocity.y * dt;
    if (m_ball.circle.x - m_ball.circle.r <= PADDLE_WIDTH) {
        m_ball.circle.x = PADDLE_WIDTH + m_ball.circle.r;
        m_ball.velocity.x *= -1.0f;
        m_ball.velocity.y *= -1.0f;
    }
    if (m_ball.circle.x + m_ball.circle.r > 4.0f - PADDLE_WIDTH) {
        m_ball.circle.x = 4.0f - PADDLE_WIDTH - m_ball.circle.r;
        m_ball.velocity.x *= -1.0f;
        m_ball.velocity.y *= -1.0f;
    }
}

void
Pong::Draw()
{
    Color paddle_color = {0.6f, 0.3f, 0.3f, 1.0f};
    Rectangle paddle1_rect = {
        0.0f,
        m_paddles[0].y,
        0.0f + PADDLE_WIDTH,
        m_paddles[0].y + PADDLE_HEIGHT
    };
    Rectangle paddle2_rect = {
        4.0f - PADDLE_WIDTH,
        m_paddles[1].y,
        4.0f,
        m_paddles[1].y + PADDLE_HEIGHT
    };
    g_renderer.PushRectangle(paddle1_rect, paddle_color, z_layer1);
    g_renderer.PushRectangle(paddle2_rect, paddle_color, z_layer1);

    // Todo: draw a circle
    Rectangle ball_rectangle = {
        m_ball.circle.x - m_ball.circle.r,
        m_ball.circle.y - m_ball.circle.r,
        m_ball.circle.x + m_ball.circle.r,
        m_ball.circle.y + m_ball.circle.r
    };
    Color ball_color = {0.3f, 0.5f, 0.3f, 1.0f};
    g_renderer.PushRectangle(ball_rectangle, ball_color, z_layer1);
}