import os

import struct

import sys

root_path = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))

if root_path not in sys.path:

sys.path.append(root_path)

from bitcoinutils.block import Block

from bitcoinutils.constants import BLOCK_MAGIC_NUMBER

def main():

filename = '' # Give .dat file path to run example

try:

with open(filename, 'rb') as file:

while True:

# Read the magic number and block size (first 8 bytes: 4 bytes magic, 4 bytes size)

preamble = file.read(8)

if len(preamble) < 8:

# If less than 8 bytes were read, it's the end of the file

break

# Unpack the header to get magic number and size

magic, size = struct.unpack('<4sI', preamble)

magic_hex = magic.hex()

if magic_hex not in BLOCK_MAGIC_NUMBER:

raise ValueError(f"Unknown or unsupported network magic number: {magic_hex}")

print("Network:", BLOCK_MAGIC_NUMBER[magic_hex])

# Read the block data based on the size specified

block_data = file.read(size)

if len(block_data) < size:

# If the block data is less than the size specified, it means the file is truncated

print("Truncated block data.")

break

# Concatenate the header and block data to parse it as a raw block

raw_block = preamble + block_data

# Use the from_raw method of the Block class to parse the block

block = Block.from_raw(raw_block)

# Output some information about the block (example: hash, number of transactions)

print("Block Hash:", block.get_block_header().get_block_hash())

print("Number of Transactions:", block.get_transactions_count())

except FileNotFoundError:

print(f"Error: The file '{filename}' does not exist.")

except Exception as e:

print(f"An unexpected error occurred: {e}")

if __name__ == '__main__':

main()