/*
 * Copyright 2000-2012 JetBrains s.r.o.
 *
 * 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 com.intellij.openapi.roots.impl;

import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.module.ModifiableModuleModel;
import com.intellij.openapi.module.Module;
import com.intellij.openapi.module.impl.ModuleManagerImpl;
import com.intellij.openapi.roots.ModifiableRootModel;
import com.intellij.openapi.roots.ModuleOrderEntry;
import com.intellij.openapi.roots.ModuleRootManager;
import com.intellij.openapi.roots.RootPolicy;
import com.intellij.util.ArrayUtil;
import com.intellij.util.graph.CachingSemiGraph;
import com.intellij.util.graph.DFSTBuilder;
import com.intellij.util.graph.GraphGenerator;
import consulo.annotations.RequiredWriteAction;

import java.util.*;

public class ModifiableModelCommitter {
  private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.module.impl.ModifiableModelCommitter");

  @RequiredWriteAction
  public static void multiCommit(ModifiableRootModel[] rootModels, ModifiableModuleModel moduleModel) {
    ApplicationManager.getApplication().assertWriteAccessAllowed();

    final List<RootModelImpl> modelsToCommit = getSortedChangedModels(rootModels, moduleModel);

    final List<ModifiableRootModel> modelsToDispose = new ArrayList<ModifiableRootModel>(Arrays.asList(rootModels));
    modelsToDispose.removeAll(modelsToCommit);

    ModuleManagerImpl.commitModelWithRunnable(moduleModel, new Runnable() {
      @Override
      public void run() {
        for (RootModelImpl rootModel : modelsToCommit) {
          rootModel.doCommitAndDispose(true);
        }

        for (ModifiableRootModel model : modelsToDispose) {
          model.dispose();
        }
      }
    });
  }

  private static List<RootModelImpl> getSortedChangedModels(ModifiableRootModel[] _rootModels,
                                                    final ModifiableModuleModel moduleModel) {
    List<RootModelImpl> rootModels = new ArrayList<RootModelImpl>();
    for (ModifiableRootModel _rootModel : _rootModels) {
      RootModelImpl rootModel = (RootModelImpl)_rootModel;
      if (rootModel.isChanged()) {
        rootModels.add(rootModel);
      }
    }

    sortRootModels(rootModels, moduleModel);
    return rootModels;
  }

  private static void sortRootModels(List<RootModelImpl> rootModels, final ModifiableModuleModel moduleModel) {
    DFSTBuilder<RootModelImpl> builder = createDFSTBuilder(rootModels, moduleModel);

    final Comparator<RootModelImpl> comparator = builder.comparator();
    Collections.sort(rootModels, comparator);
  }

  private static DFSTBuilder<RootModelImpl> createDFSTBuilder(List<RootModelImpl> rootModels, final ModifiableModuleModel moduleModel) {
    final Map<String, RootModelImpl> nameToModel = new com.intellij.util.containers.HashMap<String, RootModelImpl>();
    for (final RootModelImpl rootModel : rootModels) {
      final String name = rootModel.getModule().getName();
      LOG.assertTrue(!nameToModel.containsKey(name), name);
      nameToModel.put(name, rootModel);
    }
    final Module[] modules = moduleModel.getModules();
    for (final Module module : modules) {
      final String name = module.getName();
      if (!nameToModel.containsKey(name)) {
        final RootModelImpl rootModel = ((ModuleRootManagerImpl)ModuleRootManager.getInstance(module)).getRootModel();
        nameToModel.put(name, rootModel);
      }
    }
    final Collection<RootModelImpl> allRootModels = nameToModel.values();
    return new DFSTBuilder<RootModelImpl>(new GraphGenerator<RootModelImpl>(new CachingSemiGraph<RootModelImpl>(new GraphGenerator.SemiGraph<RootModelImpl>() {
          @Override
          public Collection<RootModelImpl> getNodes() {
            return allRootModels;
          }

          @Override
          public Iterator<RootModelImpl> getIn(RootModelImpl rootModel) {
            final List<String> namesList = rootModel.orderEntries().withoutSdk().withoutLibraries().withoutModuleSourceEntries()
              .process(new RootPolicy<ArrayList<String>>() {
              @Override
              public ArrayList<String> visitModuleOrderEntry(ModuleOrderEntry moduleOrderEntry, ArrayList<String> strings) {
                final Module module = moduleOrderEntry.getModule();
                if (module != null && !module.isDisposed()) {
                  strings.add(module.getName());
                } else {
                  final Module moduleToBeRenamed = moduleModel.getModuleToBeRenamed(moduleOrderEntry.getModuleName());
                  if (moduleToBeRenamed != null && !moduleToBeRenamed.isDisposed()) {
                    strings.add(moduleToBeRenamed.getName());
                  }
                }
                return strings;
              }
            }, new ArrayList<String>());

            final String[] names = ArrayUtil.toStringArray(namesList);
            List<RootModelImpl> result = new ArrayList<RootModelImpl>();
            for (String name : names) {
              final RootModelImpl depRootModel = nameToModel.get(name);
              if (depRootModel != null) { // it is ok not to find one
                result.add(depRootModel);
              }
            }
            return result.iterator();
          }
        })));
  }
}