/*
    * 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.maven.plugins.toolchain;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugins.annotations.Component;
  import org.apache.maven.plugins.annotations.LifecyclePhase;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.toolchain.MisconfiguredToolchainException;
  import org.apache.maven.toolchain.ToolchainManagerPrivate;
  import org.apache.maven.toolchain.ToolchainPrivate;
  
  /**
   * Check that toolchains requirements are met by currently configured toolchains in {@code toolchains.xml} and
   * store the selected toolchain in build context for later retrieval by other plugins.
   *
   * @author mkleint
   */
  @Mojo(
          name = "toolchain",
          defaultPhase = LifecyclePhase.VALIDATE,
          configurator = "toolchains-requirement-configurator",
          threadSafe = true)
  public class ToolchainMojo extends AbstractMojo {
      private static final Object LOCK = new Object();
  
      /**
       */
      @Component
      private ToolchainManagerPrivate toolchainManagerPrivate;
  
      /**
       * The current build session instance. This is used for toolchain manager API calls.
       */
      @Parameter(defaultValue = "${session}", readonly = true, required = true)
      private MavenSession session;
  
      /**
       * Toolchains requirements, specified by one
       * <pre>{@code   <toolchain-type>
       *     <param>expected value</param>
       *     ...
       *   </toolchain-type>}</pre>
       * element for each required toolchain.
       */
      @Parameter(required = true)
      private ToolchainsRequirement toolchains;
  
      @Override
      public void execute() throws MojoExecutionException, MojoFailureException {
          if (toolchains == null) {
              // should not happen since parameter is required...
              getLog().warn("No toolchains requirements configured.");
              return;
          }
  
          List<String> nonMatchedTypes = new ArrayList<>();
  
          for (Map.Entry<String, Map<String, String>> entry :
                  toolchains.getToolchains().entrySet()) {
              String type = entry.getKey();
  
              if (!selectToolchain(type, entry.getValue())) {
                  nonMatchedTypes.add(type);
              }
          }
  
          if (!nonMatchedTypes.isEmpty()) {
              // TODO add the default toolchain instance if defined??
              StringBuilder buff = new StringBuilder();
              buff.append("Cannot find matching toolchain definitions for the following toolchain types:");
  
              for (String type : nonMatchedTypes) {
                  buff.append(System.lineSeparator());
                  buff.append(getToolchainRequirementAsString(type, toolchains.getParams(type)));
             }
 
             getLog().error(buff.toString());
 
             throw new MojoFailureException(buff.toString() + System.lineSeparator()
                     + "Please make sure you define the required toolchains in your ~/.m2/toolchains.xml file.");
         }
     }
 
     protected String getToolchainRequirementAsString(String type, Map<String, String> params) {
         StringBuilder buff = new StringBuilder();
 
         buff.append(type).append(" [");
 
         if (params.size() == 0) {
             buff.append(" any");
         } else {
             for (Map.Entry<String, String> param : params.entrySet()) {
                 buff.append(" ").append(param.getKey()).append("='").append(param.getValue());
                 buff.append("'");
             }
         }
 
         buff.append(" ]");
 
         return buff.toString();
     }
 
     protected boolean selectToolchain(String type, Map<String, String> params) throws MojoExecutionException {
         getLog().info("Required toolchain: " + getToolchainRequirementAsString(type, params));
         int typeFound = 0;
 
         try {
             ToolchainPrivate[] tcs = getToolchains(type);
 
             for (ToolchainPrivate tc : tcs) {
                 if (!type.equals(tc.getType())) {
                     // useful because of MNG-5716
                     continue;
                 }
 
                 typeFound++;
 
                 if (tc.matchesRequirements(params)) {
                     getLog().info("Found matching toolchain for type " + type + ": " + tc);
 
                     // store matching toolchain to build context
                     synchronized (LOCK) {
                         toolchainManagerPrivate.storeToolchainToBuildContext(tc, session);
                     }
 
                     return true;
                 }
             }
         } catch (MisconfiguredToolchainException ex) {
             throw new MojoExecutionException("Misconfigured toolchains.", ex);
         }
 
         getLog().error("No toolchain " + ((typeFound == 0) ? "found" : ("matched from " + typeFound + " found"))
                 + " for type " + type);
 
         return false;
     }
 
     private ToolchainPrivate[] getToolchains(String type)
             throws MojoExecutionException, MisconfiguredToolchainException {
         return toolchainManagerPrivate.getToolchainsForType(type, session);
     }
 }