/*
    * Copyright 2013-2020 the original author or authors.
    *
    * 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
    *
    *      https://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.springframework.cloud.contract.maven.verifier;
  
  import java.io.File;
  
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.plugin.MojoExecution;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.shared.incremental.IncrementalBuildHelper;
  import org.apache.maven.shared.incremental.IncrementalBuildHelperRequest;
  
  /**
   * Prevents the following scenario:
   *
   * 1. Contract is added
   *
   * 2. Derived file is generated
   *
   * 3. Contract is deleted
   *
   * 4. Derived file still exists
   */
  class LeftOverPrevention {
  
  	private final IncrementalBuildHelper incrementalBuildHelper;
  
  	private final File generatedDirectory;
  
  	LeftOverPrevention(File generatedDirectory, MojoExecution mojoExecution, MavenSession session)
  			throws MojoExecutionException {
  		this.generatedDirectory = generatedDirectory;
  		this.incrementalBuildHelper = new IncrementalBuildHelper(mojoExecution, session);
  		this.incrementalBuildHelper
  				.beforeRebuildExecution(new IncrementalBuildHelperRequest().outputDirectory(generatedDirectory));
  	}
  
  	void deleteLeftOvers() throws MojoExecutionException {
  		if (generatedDirectory.exists()) {
  			incrementalBuildHelper
  					.afterRebuildExecution(new IncrementalBuildHelperRequest().outputDirectory(generatedDirectory));
  		}
  	}
  
  }