/*
 * 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.apache.juneau.rest.mock.classic;

import java.io.*;

import org.apache.juneau.bct.assertions.*;

/**
 * A capturing {@link PrintStream} that allows you to easily capture console output.
 *
 * <p>
 * Stores output into an internal {@link ByteArrayOutputStream}.  Note that this means you could run into memory
 * constraints if you heavily use this class.
 *
 * <p>
 * Typically used in conjunction with the {@link org.apache.juneau.rest.client.classic.RestClient.Builder#console(PrintStream)} to capture console output for
 * testing purposes.
 *
 * <h5 class='figure'>Example:</h5>
 * <p class='bjava'>
 *    <jc>// A simple REST API that echos a posted bean.</jc>
 *    <ja>@Rest</ja>
 *    <jk>public class</jk> MyRest <jk>extends</jk> BasicRestResource {
 *       <ja>@RestPost</ja>(<js>"/bean"</js>)
 *       <jk>public</jk> Bean postBean(<ja>@Content</ja> Bean <jv>bean</jv>) {
 *          <jk>return</jk> <jv>bean</jv>;
 *       }
 *    }
 *
 * <jc>// Our mock console.</jc>
 *    MockConsole <jv>console</jv> = MockConsole.<jsm>create</jsm>();
 *
 * <jc>// Make a call against our REST API and log the call.</jc>
 *    MockRestClient
 *       .<jsm>create</jsm>(MyRest.<jk>class</jk>)
 *       .json5()
 *       .logRequests(DetailLevel.<jsf>FULL</jsf>, Level.<jsf>SEVERE</jsf>)
 *       .logToConsole()
 *       .console(<jv>console</jv>)
 *       .build()
 *       .post(<js>"/bean"</js>, <jv>bean</jv>)
 *       .run();
 *
 *    <jv>console</jv>.assertContents().is(
 *       <js>""</js>,
 *       <js>"=== HTTP Call (outgoing) ======================================================"</js>,
 *       <js>"=== REQUEST ==="</js>,
 *       <js>"POST http://localhost/bean"</js>,
 *       <js>"---request headers---"</js>,
 *       <js>" Accept: application/json5"</js>,
 *       <js>"---request entity---"</js>,
 *       <js>" Content-Type: application/json5"</js>,
 *       <js>"---request content---"</js>,
 *       <js>"{f:1}"</js>,
 *       <js>"=== RESPONSE ==="</js>,
 *       <js>"HTTP/1.1 200 "</js>,
 *       <js>"---response headers---"</js>,
 *       <js>" Content-Type: application/json"</js>,
 *       <js>"---response content---"</js>,
 *       <js>"{f:1}"</js>,
 *       <js>"=== END ======================================================================="</js>,
 *       <js>""</js>
 *    );
 * </p>
 *
 * <h5 class='section'>See Also:</h5><ul>
 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauRestMock">juneau-rest-mock</a>
 * </ul>
 */
@SuppressWarnings({
   "resource" // Stream returned to caller; lifecycle managed by the caller
})
public class MockConsole extends PrintStream {

   private final ByteArrayOutputStream baos;

   /**
    * Creator.
    *
    * @return A new {@link MockConsole} object.
    */
   public static MockConsole create() {
      return new MockConsole();
   }

   /**
    * Constructor.
    */
   public MockConsole() {
      this(new ByteArrayOutputStream());
   }

   private MockConsole(ByteArrayOutputStream baos) {
      super(baos);
      this.baos = baos;
   }

   /**
    * Allows you to perform fluent-style assertions on the contents of this buffer.
    *
    * <h5 class='figure'>Example:</h5>
    * <p class='bjava'>
    *    MockConsole <jv>console</jv> = MockConsole.<jsf>create</jsf>();
    *
    *    MockRestClient
    *       .<jsm>create</jsm>(MyRest.<jk>class</jk>)
    *       .console(<jv>console</jv>)
    *       .debug()
    *       .json5()
    *       .build()
    *       .get(<js>"/url"</js>)
    *       .run();
    *
    *    <jv>console</jv>.assertContents().isContains(<js>"HTTP GET /url"</js>);
    * </p>
    *
    * @return A new fluent-style assertion object.
    */
   public synchronized FluentStringAssertion<MockConsole> assertContents() {
      return new FluentStringAssertion<>(toString(), this);
   }

   /**
    * Allows you to perform fluent-style assertions on the size of this buffer.
    *
    * <h5 class='figure'>Example:</h5>
    * <p class='bjava'>
    *    MockConsole <jv>console</jv> = MockConsole.<jsf>create</jsf>();
    *
    *    MockRestClient
    *       .<jsm>create</jsm>(MyRest.<jk>class</jk>)
    *       .console(<jv>console</jv>)
    *       .debug()
    *       .json5()
    *       .build()
    *       .get(<js>"/url"</js>)
    *       .run();
    *
    *    <jv>console</jv>.assertSize().isGreaterThan(0);
    * </p>
    *
    * @return A new fluent-style assertion object.
    */
   public synchronized FluentIntegerAssertion<MockConsole> assertSize() {
      return new FluentIntegerAssertion<>(baos.size(), this);
   }

   /**
    * Resets the contents of this buffer.
    *
    * @return This object.
    */
   public synchronized MockConsole reset() {
      baos.reset();
      return this;
   }

   /**
    * Returns the contents of this buffer as a string.
    */
   @Override
   public String toString() {
      return baos.toString();
   }
}