block.py

from transaction import Transaction
from typing import List, Dict
from uuid import uuid4


class Block:
    def __init__(self, prev: str, transactions: List[Transaction]):
        self.prev = prev
        self.transactions = transactions
        self.reward = []
        self.id = str(uuid4())

    def to_dict(self):
        return {
            'hash': self.id,
            'transactions': [x.to_dict() for x in self.transactions],
            'prev': self.prev
        }

    def transaction_exists(self, tr: Transaction) -> bool:
        for block_transaction in self.transactions:
            if block_transaction.id == tr.id:
                return True
        return False

    def __len__(self):
        return len(self.transactions)

    def add(self, chain, rewards: List[Dict]):
        """
        :param chain:
        :param rewards:
        :return:
        """
        self.reward = rewards
        chain.add(self)
        # TODO basic sanity check for block rewards