class Chainstate:
    def __init__(self):
        # Dictionary acting as our LevelDB
        # Key: "TXID:VOUT", Value: Amount in satoshis
        self.utxo_set = {
            "genesis_tx:0": 5000000000, # 50 BTC
            "alpha_tx:0": 2500000000,   # 25 BTC
        }

    def process_transaction(self, txid, inputs, outputs):
        print(f"\n--- Processing Transaction: {txid} ---")

        # 1. Verify Inputs exist in UTXO set
        for outpoint in inputs:
            if outpoint not in self.utxo_set:
                print(f"[REJECTED] Input {outpoint} does not exist or was already spent!")
                return False

        # 2. Calculate input sum and REMOVE spent UTXOs
        total_in = 0
        for outpoint in inputs:
            total_in += self.utxo_set.pop(outpoint)
            print(f"[*] Consumed: {outpoint}")

        # 3. ADD new UTXOs from outputs
        total_out = 0
        for i, amount in enumerate(outputs):
            new_outpoint = f"{txid}:{i}"
            self.utxo_set[new_outpoint] = amount
            total_out += amount
            print(f"[*] Created:  {new_outpoint} ({amount:,} sats)")

        # 4. Calculate Fee (Implicit)
        fee = total_in - total_out
        print(f"[*] Total Fee collected by miner: {fee:,} sats")
        return True

    def show_status(self):
        print(f"\n--- Current UTXO Set Status ---")
        print(f"Total Entries: {len(self.utxo_set)}")
        for key, val in self.utxo_set.items():
            print(f" - {key}: {val:,} sats")

# --- Simulation ---
node = Chainstate()
node.show_status()

# Spend the genesis coin
node.process_transaction("payment_1", ["genesis_tx:0"], [1000000000, 3999900000])

# Spend a coin that was just created
node.process_transaction("payment_2", ["payment_1:0"], [500000000, 499900000])

node.show_status()