/*
 * Copyright 2013 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.bitcoinj.core;

import org.bitcoinj.base.Coin;

import javax.annotation.Nullable;
import java.util.Objects;

/**
 * Thrown to indicate that you don't have enough money available to perform the requested operation.
 */
public class InsufficientMoneyException extends Exception {
    /** Contains the number of satoshis that would have been required to complete the operation. */
    @Nullable
    public final Coin missing;

    protected InsufficientMoneyException() {
        this.missing = null;
    }

    public InsufficientMoneyException(Coin missing) {
        this(missing, "Insufficient money, missing " + missing.toFriendlyString());
    }

    public InsufficientMoneyException(Coin missing, String message) {
        super(message);
        this.missing = Objects.requireNonNull(missing);
    }

    public InsufficientMoneyException(Coin missing, Coin available, Coin outputs, Coin fee) {
        this(missing, format(missing, available, outputs, fee));
    }

    /**
     * @param missing Amount missing
     * @param available Amount available (e.g. found by CoinSelector)
     * @param outputs total amount of output requested
     * @param fee calculated fee required for transaction
     * @return An exception message
     */
    static String format(Coin missing, Coin available, Coin outputs, Coin fee) {
        return String.format("Insufficient money, missing %s (available: %s, total outputs: %s, fee: %s)", missing.toFriendlyString(), available.toFriendlyString(), outputs.toFriendlyString(), fee.toFriendlyString());
    }
}
