import time
import serial
import requests

# Constants
SERIAL_PORT = 'COM12'  # Change this as needed for your system
BAUD_RATE = 156500
TIMEOUT = 1
CHUNK_SIZE = 1024  # Adjust the chunk size based on your needs
DELAY_BETWEEN_CHUNK = 1  # Adjust the delay if needed

# Image URLs
image_urls = {
    1: "https://download.rechargegrid.in/download/dq111welcome.jpg",  # Show Welcome
    2: "https://download.rechargegrid.in/download/dq111qr.jpg",      # Show QR
    3: "https://download.rechargegrid.in/download/dq111bogo.jpg",    # Show BOGO
    4: "https://download.rechargegrid.in/download/dq111menu.jpg"     # Show Menu
}

# Open serial connection
def open_serial_connection():
    try:
        ser = serial.Serial(SERIAL_PORT, BAUD_RATE, timeout=TIMEOUT)
        if ser.is_open:
            print(f"Connected to {SERIAL_PORT}")
        return ser
    except serial.SerialException as e:
        print(f"Error connecting to serial port {SERIAL_PORT}: {e}")
        return None

# Close the serial connection
def close_serial_connection(ser):
    if ser and ser.is_open:
        ser.close()
        print(f"Disconnected from {SERIAL_PORT}")

# Fetch image from URL
def fetch_image(url):
    try:
        print(f"Fetching image from {url}...")
        response = requests.get(url, stream=True)
        response.raise_for_status()  # Check if the request was successful
        return response.content  # Return image as bytes
    except requests.exceptions.RequestException as e:
        print(f"Error fetching image: {e}")
        return None

# Send image to device over serial port in chunks
def write_to_serial_image(ser, data):
    if ser:
        try:
            print("Sending image in chunks to device...")
            # Prepare the first command with filename and data length
            first_command = f"StartSendingFile {time.time()}.jpeg {len(data)}\n"
            ser.write(first_command.encode())
            print(f"Sent command: {first_command}")
            # time.sleep(1)
            # Wait for the device to respond (this could be adjusted based on the device's protocol)
            response = ser.readline().decode().strip()  # Read the next line and decode it
            print(f"Device response: {response}")

            # If the device is ready to receive data, send the image in chunks
            if "Command received. Preparing to receive file..." in response:
                for i in range(0, len(data), CHUNK_SIZE):
                    chunk = data[i:i+CHUNK_SIZE]
                    ser.write(chunk)
                    print(f"Sent chunk of size {len(chunk)} bytes")
                    time.sleep(DELAY_BETWEEN_CHUNK / 1000)  # Convert milliseconds to seconds
                print("Image transfer complete.")
                response = ser.readline().decode().strip()  # Read the next line and decode it
                print(f"Device response after transfer: {response}")

                # Wait for the device to indicate it is ready for the next file
                time.sleep(1)  # Add a delay to ensure the device has processed the file
              

                # Check again if device is ready before sending the next file
                ready_response = ser.readline().decode().strip()
                print(f"Device readiness check: {ready_response}")

                if "File size verified" in ready_response:
                    print("Device is ready for the next file.")
                else:
                    print("Device is still not ready, retrying after delay.")
                    time.sleep(5)  # Longer delay before retrying
            else:
                print("Device is not ready to receive data.")
        except Exception as e:
            print(f"Error while sending data: {e}")

# Main function
def main():
    ser = open_serial_connection()  # Open the serial connection
    if not ser:
        print("Could not establish serial connection. Exiting.")
        return

    try:
        while True:
            print("\nSelect an option:")
            print("1. Show Welcome")
            print("2. Show QR")
            print("3. Show BOGO")
            print("4. Show Menu")
            print("5. Exit")

            try:
                choice = int(input("Enter your choice: "))
                if choice == 5:
                    print("Exiting program...")
                    break
                elif choice in image_urls:
                    url = image_urls[choice]  # Fetch the image URL based on user selection
                    image_data = fetch_image(url)  # Fetch the selected image
                    if image_data:
                        write_to_serial_image(ser, image_data)  # Send the image to the device
                else:
                    print("Invalid option, please try again.")
            except ValueError:
                print("Invalid input. Please enter a number between 1 and 5.")

    finally:
        print("Connection Closed")
        close_serial_connection(ser)  # Close the serial connection when done

if __name__ == "__main__":
    main()