// Physics scaling: 10 = 1.0 pixel, 15 = 1.5 pixels, etc.
DEFINE SCALE 10 

DEFINE BALL_RADIUS 2
DEFINE PADDLE_WIDTH 3
DEFINE PADDLE_HEIGHT 30
DEFINE BALL_PADDLE_TOUCH_POINT_X ((BALL_RADIUS+PADDLE_WIDTH)*SCALE)
DEFINE PADDLE_MOVEMENT_STEP 6

DEFINE RE_CW 24
DEFINE RE_CCW 25

DEFINE OLED_HEIGHT 128
DEFINE OLED_WIDTH 128
DEFINE PADDLE_MIN_Y (PADDLE_HEIGHT/2)
DEFINE PADDLE_MAX_Y (OLED_HEIGHT - PADDLE_MIN_Y)

// --- Global Variables ---
// Positions are SCALED (Pixel * SCALE)
VAR ball_x = 640
VAR ball_y = 640

// Velocity is SCALED
VAR vel_x = 30
VAR vel_y = 20

VAR paddle_pos_y = 64
VAR score = 0

// --- Functions ---

FUN draw_court()
    // Top, Right, Bottom walls
    OLED_LINE 0 0 127 0
    OLED_LINE 127 0 127 127
    OLED_LINE 0 127 127 127
END_FUN

FUN draw_paddle()
    VAR p_top = paddle_pos_y - (PADDLE_HEIGHT/2)
    VAR p_bot = paddle_pos_y + (PADDLE_HEIGHT/2)
    
    // x1, y1, x2, y2, filled(1)
    OLED_RECT 0 p_top PADDLE_WIDTH p_bot 1
END_FUN

FUN draw_ball()
    // Descale coordinates for drawing
    VAR d_x = ball_x / SCALE
    VAR d_y = ball_y / SCALE
    
    OLED_CIRCLE d_x d_y BALL_RADIUS 1
END_FUN

FUN game_over()
    SWC_FILL 255 0 0
    
    OLED_CURSOR 0 40
    OLED_CPRINT GAME OVER
    
    OLED_CURSOR 0 60
    OLED_CPRINT Score: $score

    OLED_CURSOR 0 100
    OLED_CPRINT Press Any Key
    
    OLED_UPDATE
    
    WHILE TRUE
        IF $_BLOCKING_READKEY <= 20 THEN
            SWC_RESET 99
            HALT
        END_IF
    END_WHILE
END_FUN

FUN update_paddle()
    VAR key = _READKEY
    
    // Rotary logic
    IF key == RE_CCW
        paddle_pos_y = paddle_pos_y + PADDLE_MOVEMENT_STEP
    ELSE IF key == RE_CW
        paddle_pos_y = paddle_pos_y - PADDLE_MOVEMENT_STEP
    END_IF
    
    // Bounds checking
    IF paddle_pos_y > PADDLE_MAX_Y
        paddle_pos_y = PADDLE_MAX_Y
    END_IF
    IF paddle_pos_y < PADDLE_MIN_Y
        paddle_pos_y = PADDLE_MIN_Y
    END_IF
END_FUN

FUN increase_difficulty()
    // Increase X speed by 0.3 pixels (3 scaled units)
    // Maintain direction
    IF vel_x > 0
        vel_x = vel_x + 3
    ELSE
        vel_x = vel_x - 3
    END_IF
    
    // Randomize Y speed slightly for chaos
    // Add random integer between -5 and 5
    VAR jitter = RANDINT(-5, 5)
    vel_y = vel_y + jitter
END_FUN

FUN physics_step()
    // Apply velocity
    ball_x = ball_x + vel_x
    ball_y = ball_y + vel_y
    
    // --- Wall Collisions (Top/Bottom/Right) ---
    
    // Right Wall (127 * 10 = 1270)
    IF ball_x >= 1250
        ball_x = 1250
        vel_x = vel_x * -1
    END_IF
    
    // Bottom Wall
    IF ball_y >= 1250
        ball_y = 1250
        vel_y = vel_y * -1
        // Add ricochet angle randomness
        vel_x = vel_x + RANDINT(-3, 3) 
    END_IF
    
    // Top Wall
    IF ball_y <= 20
        ball_y = 20
        vel_y = vel_y * -1
        // Add ricochet angle randomness
        vel_x = vel_x + RANDINT(-3, 3)
    END_IF
    
    // --- Paddle Collision (Left Side) ---
    
    // Check if ball is at paddle X plane
    IF ball_x <= BALL_PADDLE_TOUCH_POINT_X
        // Descale Y for comparison
        VAR ball_pixel_y = ball_y / SCALE

        VAR p_top = paddle_pos_y - (PADDLE_HEIGHT/2)
        VAR p_bot = paddle_pos_y + (PADDLE_HEIGHT/2)
        
        IF ball_pixel_y >= p_top && ball_pixel_y <= p_bot
            // HIT!
            ball_x = BALL_PADDLE_TOUCH_POINT_X
            vel_x = vel_x * -1
            score = score + 1
            
            SWC_FILL $_RANDOM_INT%255 $_RANDOM_INT%255 $_RANDOM_INT%255
            
            increase_difficulty()
        ELSE IF ball_x <= 0
            // MISS!
            game_over()
        END_IF
    END_IF
    
END_FUN

// --- Main Execution ---

SWC_FILL 0 255 0

WHILE 1
    update_paddle()
    physics_step()

    OLED_CLEAR
    draw_court()
    draw_paddle()
    draw_ball()
    OLED_UPDATE
    
    // Frame delay
    DELAY 20
END_WHILE