import requests
import time

# RPC endpoint for connecting to the Ethereum-compatible network
RPC_URL = "https://eth.llamarpc.com"

def get_latest_block_number():
    """
    Sends a JSON-RPC request to the node to retrieve the latest block number.
    Returns the block number as an integer.
    """
    payload = {
        "jsonrpc": "2.0",             # JSON-RPC protocol version
        "method": "eth_blockNumber",  # Method to get the latest block number
        "params": [],                 # No parameters required for this method
        "id": 1                       # Request ID (for tracking)
    }

    try:
        # Send an HTTP POST request to the RPC endpoint
        response = requests.post(RPC_URL, json=payload)
        response.raise_for_status()   # Raise an exception for non-200 responses
        data = response.json()        # Parse the JSON response

        # Extract the hexadecimal block number, e.g. "0x10d4f"
        block_hex = data.get("result", "0x0")

        # Convert hexadecimal to integer
        block_number = int(block_hex, 16)

        return block_number
    except Exception as e:
        # Print any errors encountered during the request
        print("Error fetching block number:", e)
        return None


if __name__ == "__main__":
    # Continuous loop: fetch and print the latest block height
    while True:
        block_number = get_latest_block_number()
        if block_number is not None:
            print(f"Latest block height: {block_number}")
        # Adjust sleep time as needed to reduce RPC load (in seconds)
        time.sleep(0)