from machine import Pin, SPI
from time import sleep

# Initialiseer SPI
spi = SPI(1, baudrate=1000000, polarity=0, phase=0, sck=Pin(18), mosi=Pin(23))
ss = Pin(5, Pin.OUT)
ss.value(1)

NUM_DISPLAYS = 4  # 4 x 8x8 displays

# MAX7219 registers
DECODE_MODE = 0x09
INTENSITY = 0x0A
SCAN_LIMIT = 0x0B
SHUTDOWN = 0x0C
DISPLAY_TEST = 0x0F

# 8x8 smiley bitmap (1 byte per row)
SMILEY = [
    0b00111100,
    0b01000010,
    0b10100101,
    0b10000001,
    0b10100101,
    0b10011001,
    0b01000010,
    0b00111100
]

def send_frame(rows):
    """Stuurt 8 rijen tegelijk naar alle 4 displays"""
    for row in range(8):
        ss.value(0)
        # Let op: volgorde is van meest rechtse naar meest linkse display (omgekeerd!)
        for display in reversed(range(NUM_DISPLAYS)):
            spi.write(bytearray([row + 1, rows[display][row]]))
        ss.value(1)

def setup_max7221():
    for reg, val in [
        (SHUTDOWN, 0x01),
        (DISPLAY_TEST, 0x00),
        (DECODE_MODE, 0x00),
        (SCAN_LIMIT, 0x07),
        (INTENSITY, 0x08)
    ]:
        ss.value(0)
        for _ in range(NUM_DISPLAYS):
            spi.write(bytearray([reg, val]))
        ss.value(1)

def clear_display():
    empty = [[0] * 8 for _ in range(NUM_DISPLAYS)]
    send_frame(empty)

def smiley_to_columns():
    """Converteer smiley van rijen naar kolommen"""
    cols = [0] * 8
    for col in range(8):
        byte = 0
        for row in range(8):
            if (SMILEY[row] >> (7 - col)) & 1:
                byte |= (1 << row)
        cols[col] = byte
    return cols

def draw_smiley_at(offset):
    """
    Plaats smiley op offset (0–31). Negatieve waarden tonen smiley nog buiten beeld links.
    """
    full_cols = [0] * 32
    smiley_cols = smiley_to_columns()
    for i in range(8):
        pos = offset + i
        if 0 <= pos < 32:
            full_cols[pos] = smiley_cols[i]

    # Opsplitsen in 4 displays van telkens 8 kolommen
    displays = []
    for d in range(NUM_DISPLAYS):
        block = full_cols[d*8:(d+1)*8]
        # converteer kolommen naar rijen
        rows = [0] * 8
        for col in range(8):
            for row in range(8):
                if (block[col] >> row) & 1:
                    rows[row] |= (1 << (7 - col))
        displays.append(rows)

    send_frame(displays)

# Init en loop
setup_max7221()
clear_display()

while True:
    for offset in range(-8, 32):  # van buiten beeld links tot buiten beeld rechts
        draw_smiley_at(offset)
        sleep(0.1)