import time
import board
import digitalio

# ============================================
# 4x4 KEYPAD SETUP
# ============================================

# Define keypad rows and columns (GP6-GP13 as per your diagram)
rows = [board.GP6, board.GP7, board.GP8, board.GP9]   # Row pins (GP6-GP9)
cols = [board.GP10, board.GP11, board.GP12, board.GP13] # Column pins (GP10-GP13)

# Keypad mapping (4x4)
KEYPAD = {
    (0, 0): '1', (0, 1): '2', (0, 2): '3', (0, 3): 'A',
    (1, 0): '4', (1, 1): '5', (1, 2): '6', (1, 3): 'B',
    (2, 0): '7', (2, 1): '8', (2, 2): '9', (2, 3): 'C',
    (3, 0): '*', (3, 1): '0', (3, 2): '#', (3, 3): 'D'
}

# Initialize row pins as outputs
row_pins = []
for pin in rows:
    row = digitalio.DigitalInOut(pin)
    row.direction = digitalio.Direction.OUTPUT
    row.value = False  # Start with all rows LOW
    row_pins.append(row)

# Initialize column pins as inputs with pull-down
col_pins = []
for pin in cols:
    col = digitalio.DigitalInOut(pin)
    col.direction = digitalio.Direction.INPUT
    col.pull = digitalio.Pull.DOWN  # Pull-down for column detection
    col_pins.append(col)

# ============================================
# 7-SEGMENT DISPLAY SETUP (Active HIGH, Common Cathode)
# ============================================

# 7-segment character map (a,b,c,d,e,f,g)
# 1 = ON, 0 = OFF (Active HIGH)
segments = {
    '0': [1, 1, 1, 1, 1, 1, 0],  # a,b,c,d,e,f on, g off
    '1': [0, 1, 1, 0, 0, 0, 0],  # b,c on
    '2': [1, 1, 0, 1, 1, 0, 1],  # a,b,d,e,g on
    '3': [1, 1, 1, 1, 0, 0, 1],  # a,b,c,d,g on
    '4': [0, 1, 1, 0, 0, 1, 1],  # b,c,f,g on
    '5': [1, 0, 1, 1, 0, 1, 1],  # a,c,d,f,g on
    '6': [1, 0, 1, 1, 1, 1, 1],  # a,c,d,e,f,g on
    '7': [1, 1, 1, 0, 0, 0, 0],  # a,b,c on
    '8': [1, 1, 1, 1, 1, 1, 1],  # all segments on
    '9': [1, 1, 1, 1, 0, 1, 1],  # a,b,c,d,f,g on
    'A': [1, 1, 1, 0, 1, 1, 1],  # a,b,c,e,f,g on
    'B': [0, 0, 1, 1, 1, 1, 1],  # c,d,e,f,g on
    'C': [1, 0, 0, 1, 1, 1, 0],  # a,d,e,f on
    'D': [0, 1, 1, 1, 1, 0, 1],  # b,c,d,e,g on
    'E': [1, 0, 0, 1, 1, 1, 1],  # a,d,e,f,g on
    'F': [1, 0, 0, 0, 1, 1, 1],  # a,e,f,g on
    '-': [0, 0, 0, 0, 0, 0, 1],  # g segment only
    'h': [0, 0, 1, 0, 1, 1, 1],  # c,e,f,g on
    ' ': [0, 0, 0, 0, 0, 0, 0]   # all off
}

# 7-segment pins (GP16-GP22)
# a=GP16, b=GP17, c=GP18, d=GP19, e=GP20, f=GP21, g=GP22
seg_pins = [
    board.GP16,  # a
    board.GP17,  # b
    board.GP18,  # c
    board.GP19,  # d
    board.GP20,  # e
    board.GP21,  # f
    board.GP22   # g
]

# Initialize segment pins as outputs
seg_outputs = []
for pin in seg_pins:
    seg = digitalio.DigitalInOut(pin)
    seg.direction = digitalio.Direction.OUTPUT
    seg_outputs.append(seg)

# ============================================
# KEYPAD SCANNING FUNCTION
# ============================================

def scan_keypad():
    """Scan the 4x4 keypad and return the pressed key or None"""
    for row_idx, row_pin in enumerate(row_pins):
        # Set current row HIGH
        row_pin.value = True
        
        # Check each column
        for col_idx, col_pin in enumerate(col_pins):
            if col_pin.value:  # Button pressed
                row_pin.value = False  # Reset row
                return KEYPAD.get((row_idx, col_idx))
        
        # Reset row to LOW
        row_pin.value = False
    
    return None  # No key pressed

# ============================================
# DISPLAY FUNCTION
# ============================================

def display(char):
    """Display a character on the 7-segment display"""
    # Get the pattern for the character (default to space if not found)
    pattern = segments.get(char, segments[' '])
    
    # Set each segment pin
    for i in range(7):
        seg_outputs[i].value = pattern[i]

def display_number(num):
    """Display a single digit number (0-9)"""
    display(str(num))

def clear_display():
    """Turn off all segments"""
    display(' ')

# ============================================
# TEST FUNCTION
# ============================================

def test_display():
    """Test all segments by displaying 8.8.8.8"""
    print("Testing 7-segment display...")
    for i in range(8):
        display('8')
        time.sleep(0.2)
        clear_display()
        time.sleep(0.1)
    display('0')
    print("Test complete")

# ============================================
# MAIN LOOP
# ============================================

# Test display on startup
test_display()

print("=== 4x4 Keypad to 7-Segment Display ===")
print("Press any key on the keypad")
print("Available keys: 0-9, A-D, *, #")
print("-" * 40)

last_key = None

while True:
    # Scan for key press
    key = scan_keypad()
    
    # Only process if a key is pressed and it's different from last key
    if key is not None and key != last_key:
        print(f"Key pressed: {key}")
        
        # Display based on key type
        if key.isdigit():           # Numbers 0-9
            display(key)
        elif key in ['A', 'B', 'C', 'D']:  # Letters A-D
            display(key)
        elif key == '*':            # Star key
            display('-')            # Show dash
        elif key == '#':            # Hash key
            display('h')            # Show 'h' for hash
        else:
            print(f"Unknown key: {key}")
        
        last_key = key
    
    # Reset last_key when no key is pressed
    elif key is None:
        last_key = None
    
    # Small delay to prevent excessive scanning
    time.sleep(0.05)