/*
 * SonarQube
 * Copyright (C) 2009-2017 SonarSource SA
 * mailto:info AT sonarsource DOT com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.scanner.bootstrap;

import com.google.common.base.Preconditions;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import javax.annotation.CheckForNull;

import org.picocontainer.Startable;
import org.sonar.api.Plugin;
import org.sonar.api.utils.log.Logger;
import org.sonar.api.utils.log.Loggers;
import org.sonar.core.platform.PluginInfo;
import org.sonar.core.platform.PluginLoader;
import org.sonar.core.platform.PluginRepository;

/**
 * Orchestrates the installation and loading of plugins
 */
public class ScannerPluginRepository implements PluginRepository, Startable {
  private static final Logger LOG = Loggers.get(ScannerPluginRepository.class);

  private final PluginInstaller installer;
  private final PluginLoader loader;

  private Map<String, Plugin> pluginInstancesByKeys;
  private Map<String, PluginInfo> infosByKeys;
  private Map<ClassLoader, String> keysByClassLoader;

  public ScannerPluginRepository(PluginInstaller installer, PluginLoader loader) {
    this.installer = installer;
    this.loader = loader;
  }

  @Override
  public void start() {
    infosByKeys = new HashMap<>(installer.installRemotes());
    pluginInstancesByKeys = new HashMap<>(loader.load(infosByKeys));

    // this part is only used by tests
    for (Map.Entry<String, Plugin> entry : installer.installLocals().entrySet()) {
      String pluginKey = entry.getKey();
      PluginInfo pluginInfo = new PluginInfo(pluginKey);
      infosByKeys.put(pluginKey, pluginInfo);
      pluginInstancesByKeys.put(pluginKey, entry.getValue());
    }

    keysByClassLoader = new HashMap<>();
    for (Map.Entry<String, Plugin> e : pluginInstancesByKeys.entrySet()) {
      keysByClassLoader.put(e.getValue().getClass().getClassLoader(), e.getKey());
    }

    logPlugins();
  }

  @CheckForNull
  public String getPluginKey(ClassLoader cl) {
    return keysByClassLoader.get(cl);
  }

  private void logPlugins() {
    if (infosByKeys.isEmpty()) {
      LOG.debug("No plugins loaded");
    } else {
      LOG.debug("Plugins:");
      for (PluginInfo p : infosByKeys.values()) {
        LOG.debug("  * {} {} ({})", p.getName(), p.getVersion(), p.getKey());
      }
    }
  }

  @Override
  public void stop() {
    // close plugin classloaders
    loader.unload(pluginInstancesByKeys.values());

    pluginInstancesByKeys.clear();
    infosByKeys.clear();
  }

  @Override
  public Collection<PluginInfo> getPluginInfos() {
    return infosByKeys.values();
  }

  @Override
  public PluginInfo getPluginInfo(String key) {
    PluginInfo info = infosByKeys.get(key);
    Preconditions.checkState(info != null, "Plugin [%s] does not exist", key);
    return info;
  }

  @Override
  public Plugin getPluginInstance(String key) {
    Plugin instance = pluginInstancesByKeys.get(key);
    Preconditions.checkState(instance != null, "Plugin [%s] does not exist", key);
    return instance;
  }

  @Override
  public boolean hasPlugin(String key) {
    return infosByKeys.containsKey(key);
  }
}