from machine import Pin, I2C
import ssd1306

# ESP32 Pin assignment 
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

# Joystick Pins
joystick_x_pin = Pin(4, Pin.IN)
joystick_y_pin = Pin(2, Pin.IN)

def draw_character(data, x, y):
    for row in range(16):  # 遍歷每一行，因為我們的字型是16x16的點陣圖
        for byte_index in range(2):  # 因為我們是以8位的byte來存儲，一行需要2個byte（16位元）
            # 根據行數和位元組索引來計算我們在資料中的位置
            byte_val = data[row * 2 + byte_index]  
            # 計算X軸的起始位置。我們知道每個位元組有8個點，所以乘以8
            x_0 = x + byte_index * 8
            # 計算Y軸的位置，因為我們在遍歷每一行時，y座標會增加
            y_0 = y + row
            for bit in range(8):  # 遍歷位元組中的每一位
                # 這裡我們使用一個遮罩來檢查byte_val中的特定位元是否為1。
                # 1 << (7 - bit) 會產生如下的遮罩: 10000000, 01000000, ... , 00000001
                # 然後我們用位元與運算(&)來檢查byte_val的這一位是否被設為1。
                if byte_val & (1 << (7 - bit)): 
                    oled.pixel(x_0 + bit, y_0, 1)  # 如果是1，則在OLED上繪製一個點
                    print('1', end='')  # 也在終端上印出1
                else:
                    print(' ', end='')  # 如果不是，則在終端上印出空格
        print()  # 在終端上換行，以對應到下一行的繪製
      
character_data = [
0x00, 0x00,
0x00, 0x00, 
0x7f, 0xfe, 
0x7f, 0xfe, 
0x63, 0xc6, 
0x6b, 0xd6, 
0x63, 0xc6, 
0x7f, 0xfe, 
0x7f, 0xfe, 
0x03, 0xc0, 
0x0f, 0xf0, 
0x0f, 0xf0, 
0x03, 0xc0, 
0x7f, 0xfe, 
0x7f, 0xfe, 
0x00, 0x00
]

# Initial position of the character
character_x = 56
character_y = 24

# Main loop
while True:
    oled.fill(0)  # Clear the display

    # Read joystick inputs
    joystick_x = joystick_x_pin.value()
    joystick_y = joystick_y_pin.value()

    # Adjust joystick inputs to consider center as (0, 0)
    joystick_x_adjusted = (joystick_x - 0.5) * 2
    joystick_y_adjusted = (joystick_y - 0.5) * 2

    # Update character position based on adjusted joystick inputs
    character_x += joystick_x_adjusted
    character_y += joystick_y_adjusted

    # Ensure the character stays within the OLED bounds
    character_x = max(0, min(oled_width - 16, int(character_x)))
    character_y = max(0, min(oled_height - 16, int(character_y)))

    # Draw the character at the updated position
    draw_character(character_data, character_x, character_y)

    # Refresh the OLED to see the character
    oled.show()