import machine
import time
from keypad import Keypad  # Assuming you have a keypad library for Raspberry Pi Pico

# Define GPIO pins for keypad rows and columns
ROWS = [0, 1, 2, 3]  # Adjust pin numbers as per your wiring
COLS = [4, 5, 6, 7]  # Adjust pin numbers as per your wiring

# Define keypad layout
keypad_layout = [
    ['1', '2', '3', 'A'],
    ['4', '5', '6', 'B'],
    ['7', '8', '9', 'C'],
    ['*', '0', '#', 'D']
]

# Initialize keypad
keypad = Keypad(ROWS, COLS, keypad_layout)

# Define GPIO pins for stepper motor control
STEP_PIN = machine.Pin(17, machine.Pin.OUT)    # Adjust pin numbers as per your wiring
DIR_PIN = machine.Pin(16, machine.Pin.OUT)     # Adjust pin numbers as per your wiring
ENABLE_PIN = machine.Pin(10, machine.Pin.OUT) # Adjust pin numbers as per your wiring

# Define stepper motor parameters
STEPS_PER_REV = 200  # Number of steps per revolution
MOTOR_SPEED = 500    # Initial motor speed (steps per second)

# Function to control the stepper motor
def control_stepper(steps, direction, speed):
    # Set motor direction
    DIR_PIN.value(direction)
    
    # Enable motor driver
    ENABLE_PIN.value(0)
    
    # Move motor
    for _ in range(steps):
        STEP_PIN.value(1)
        time.sleep_us(int(1e6 / (2 * speed)))  # Calculate delay based on motor speed
        STEP_PIN.value(0)
        time.sleep_us(int(1e6 / (2 * speed)))  # Calculate delay based on motor speed
    
    # Disable motor driver
    ENABLE_PIN.value(1)

# Function to read input from keypad
def read_keypad():
    key = None
    while key is None:
        key = keypad.getKey()
    return key

# Function to convert keypad input to integer
def parse_input(input_str):
    try:
        return int(input_str)
    except ValueError:
        return None

# Main program loop
while True:
    # Get user input for liquid amount
    print("Enter liquid amount (mL): ")
    liquid_amount = parse_input(read_keypad())
    if liquid_amount is None:
        print("Invalid input. Please enter a number.")
        continue
    
    # Get user input for infusion time
    print("Enter infusion time (seconds): ")
    infusion_time = parse_input(read_keypad())
    if infusion_time is None:
        print("Invalid input. Please enter a number.")
        continue
    
    # Calculate steps required to deliver the liquid amount
    steps = int(STEPS_PER_REV * liquid_amount)
    
    # Calculate motor speed based on infusion time
    if infusion_time > 0:
        speed = steps / infusion_time
    else:
        speed = MOTOR_SPEED  # Use default speed if infusion time is 0
    
    # Set motor direction (for infusion)
    direction = 1
    
    # Control the stepper motor to deliver the liquid
    control_stepper(steps, direction, speed)
    
    print("Infusion complete.")