/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.eclipse.aether.transfer;

import org.eclipse.aether.RepositoryException;

/**
 * Thrown in case of a checksum failure during an artifact/metadata download.
 */
public class ChecksumFailureException extends RepositoryException {

    private final String expected;

    private final String expectedKind;

    private final String actual;

    private final boolean retryWorthy;

    /**
     * Creates a new exception with the specified expected, expected kind and actual checksum. The resulting exception
     * is {@link #isRetryWorthy() retry-worthy}.
     *
     * @param expected The expected checksum as declared by the hosting repository, may be {@code null}.
     * @param expectedKind The expected checksum kind, may be {@code null}.
     * @param actual The actual checksum as computed from the local bytes, may be {@code null}.
     * @since 1.8.0
     */
    public ChecksumFailureException(String expected, String expectedKind, String actual) {
        super("Checksum validation failed, expected '"
                + expected + "'" + (expectedKind == null ? "" : " (" + expectedKind + ")")
                + " but is actually '" + actual + "'");
        this.expected = expected;
        this.expectedKind = expectedKind;
        this.actual = actual;
        this.retryWorthy = true;
    }

    /**
     * Creates a new exception with the specified detail message. The resulting exception is not
     * {@link #isRetryWorthy() retry-worthy}.
     *
     * @param message The detail message, may be {@code null}.
     */
    public ChecksumFailureException(String message) {
        this(false, message, null);
    }

    /**
     * Creates a new exception with the specified cause. The resulting exception is not {@link #isRetryWorthy()
     * retry-worthy}.
     *
     * @param cause The exception that caused this one, may be {@code null}.
     */
    public ChecksumFailureException(Throwable cause) {
        this("Checksum validation failed" + getMessage(": ", cause), cause);
    }

    /**
     * Creates a new exception with the specified detail message and cause. The resulting exception is not
     * {@link #isRetryWorthy() retry-worthy}.
     *
     * @param message The detail message, may be {@code null}.
     * @param cause The exception that caused this one, may be {@code null}.
     */
    public ChecksumFailureException(String message, Throwable cause) {
        this(false, message, cause);
    }

    /**
     * Creates a new exception with the specified retry flag, detail message and cause.
     *
     * @param retryWorthy {@code true} if the exception is retry-worthy, {@code false} otherwise.
     * @param message The detail message, may be {@code null}.
     * @param cause The exception that caused this one, may be {@code null}.
     */
    public ChecksumFailureException(boolean retryWorthy, String message, Throwable cause) {
        super(message, cause);
        this.expected = "";
        this.expectedKind = "";
        this.actual = "";
        this.retryWorthy = retryWorthy;
    }

    /**
     * Gets the expected checksum for the downloaded artifact/metadata.
     *
     * @return The expected checksum as declared by the hosting repository or {@code null} if unknown.
     */
    public String getExpected() {
        return expected;
    }

    /**
     * Gets the expected checksum kind for the downloaded artifact/metadata.
     *
     * @return The expected checksum kind or {@code null} if unknown.
     * @since 1.8.0
     */
    public String getExpectedKind() {
        return expectedKind;
    }

    /**
     * Gets the actual checksum for the downloaded artifact/metadata.
     *
     * @return The actual checksum as computed from the local bytes or {@code null} if unknown.
     */
    public String getActual() {
        return actual;
    }

    /**
     * Indicates whether the corresponding download is retry-worthy.
     *
     * @return {@code true} if retrying the download might solve the checksum failure, {@code false} if the checksum
     *         failure is non-recoverable.
     */
    public boolean isRetryWorthy() {
        return retryWorthy;
    }
}
