/*
 * Copyright 2000-2014 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.ide;

import com.intellij.concurrency.JobScheduler;
import com.intellij.ide.util.PropertiesComponent;
import com.intellij.notification.*;
import com.intellij.openapi.application.Application;
import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.application.ApplicationNamesInfo;
import com.intellij.openapi.application.PathManager;
import com.intellij.openapi.components.ApplicationComponent;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.ui.MessageType;
import com.intellij.openapi.ui.Messages;
import com.intellij.openapi.ui.popup.Balloon;
import com.intellij.openapi.ui.popup.JBPopupFactory;
import com.intellij.openapi.util.*;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.openapi.wm.WindowManager;
import com.intellij.ui.HyperlinkAdapter;
import com.intellij.ui.awt.RelativePoint;
import com.intellij.util.SystemProperties;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.PropertyKey;

import javax.swing.*;
import javax.swing.event.HyperlinkEvent;
import java.awt.*;
import java.io.File;
import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;

public class SystemHealthMonitor extends ApplicationComponent.Adapter {
  private static final Logger LOG = Logger.getInstance("#com.intellij.ide.SystemHealthMonitor");

  private static final NotificationGroup GROUP = new NotificationGroup("System Health", NotificationDisplayType.STICKY_BALLOON, false);
  private static final NotificationGroup LOG_GROUP = NotificationGroup.logOnlyGroup("System Health (minor)");

  @NotNull private final PropertiesComponent myProperties;

  public SystemHealthMonitor(@NotNull PropertiesComponent properties) {
    myProperties = properties;
  }

  @Override
  public void initComponent() {
    checkJvm();
    startDiskSpaceMonitoring();
    checkPowerSaveMode();
  }

  private void checkJvm() {
    if (StringUtil.containsIgnoreCase(System.getProperty("java.vm.name", ""), "OpenJDK") && !SystemInfo.isJavaVersionAtLeast("1.7")) {
      notifyUnsupportedJvm("unsupported.jvm.openjdk.message");
    }
    else if (StringUtil.endsWithIgnoreCase(System.getProperty("java.version", ""), "-ea")) {
      notifyUnsupportedJvm("unsupported.jvm.ea.message");
    }
  }

  private void notifyUnsupportedJvm(@PropertyKey(resourceBundle = "messages.IdeBundle") final String key) {
    final String ignoreKey = "ignore." + key;
    final String message = IdeBundle.message(key) + IdeBundle.message("unsupported.jvm.link");
    showNotification(ignoreKey, message, new HyperlinkAdapter() {
      @Override
      protected void hyperlinkActivated(HyperlinkEvent e) {
        myProperties.setValue(ignoreKey, "true");
      }
    });
  }

  private void showNotification(final String ignoreKey, final String message, final HyperlinkAdapter hyperlinkAdapter) {
    if (myProperties.isValueSet(ignoreKey)) {
      return;
    }

    final Application app = ApplicationManager.getApplication();
    app.getMessageBus().connect(app).subscribe(AppLifecycleListener.TOPIC, new AppLifecycleListener.Adapter() {
      @Override
      public void appFrameCreated(String[] commandLineArgs, @NotNull Ref<Boolean> willOpenProject) {
        app.invokeLater(new Runnable() {
          public void run() {
            JComponent component = WindowManager.getInstance().findVisibleFrame().getRootPane();
            if (component != null) {
              Rectangle rect = component.getVisibleRect();
              JBPopupFactory.getInstance()
                .createHtmlTextBalloonBuilder(message, MessageType.WARNING, hyperlinkAdapter)
                .setFadeoutTime(-1)
                .setHideOnFrameResize(false)
                .setHideOnLinkClick(true)
                .setDisposable(app)
                .createBalloon()
                .show(new RelativePoint(component, new Point(rect.x + 30, rect.y + rect.height - 10)), Balloon.Position.above);
            }

            Notification notification = LOG_GROUP.createNotification(message, NotificationType.WARNING);
            notification.setImportant(true);
            Notifications.Bus.notify(notification);
          }
        });
      }
    });
  }

  private static void startDiskSpaceMonitoring() {
    if (SystemProperties.getBooleanProperty("idea.no.system.path.space.monitoring", false)) {
      return;
    }

    final File file = new File(PathManager.getSystemPath());
    final AtomicBoolean reported = new AtomicBoolean();
    final ThreadLocal<Future<Long>> ourFreeSpaceCalculation = new ThreadLocal<Future<Long>>();

    JobScheduler.getScheduler().schedule(new Runnable() {
      private static final long LOW_DISK_SPACE_THRESHOLD = 50 * 1024 * 1024;
      private static final long MAX_WRITE_SPEED_IN_BPS = 500 * 1024 * 1024;  // 500 MB/sec is near max SSD sequential write speed

      @Override
      public void run() {
        if (!reported.get()) {
          Future<Long> future = ourFreeSpaceCalculation.get();
          if (future == null) {
            ourFreeSpaceCalculation.set(future = ApplicationManager.getApplication().executeOnPooledThread(new Callable<Long>() {
              @Override
              public Long call() throws Exception {
                return file.getUsableSpace();
              }
            }));
          }
          if (!future.isDone() || future.isCancelled()) {
            JobScheduler.getScheduler().schedule(this, 1, TimeUnit.SECONDS);
            return;
          }

          try {
            final long fileUsableSpace = future.get();
            final long timeout = Math.max(5, (fileUsableSpace - LOW_DISK_SPACE_THRESHOLD) / MAX_WRITE_SPEED_IN_BPS);
            ourFreeSpaceCalculation.set(null);

            if (fileUsableSpace < LOW_DISK_SPACE_THRESHOLD) {
              if (!notificationsComponentIsLoaded()) {
                ourFreeSpaceCalculation.set(future);
                JobScheduler.getScheduler().schedule(this, 1, TimeUnit.SECONDS);
                return;
              }
              reported.compareAndSet(false, true);

              //noinspection SSBasedInspection
              SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                  String productName = ApplicationNamesInfo.getInstance().getFullProductName();
                  String message = IdeBundle.message("low.disk.space.message", productName);
                  if (fileUsableSpace < 100 * 1024) {
                    LOG.warn(message);
                    Messages.showErrorDialog(message, "Fatal Configuration Problem");
                    reported.compareAndSet(true, false);
                    restart(timeout);
                  }
                  else {
                    GROUP.createNotification(message, file.getPath(), NotificationType.ERROR, null).whenExpired(new Runnable() {
                      @Override
                      public void run() {
                        reported.compareAndSet(true, false);
                        restart(timeout);
                      }
                    }).notify(null);
                  }
                }
              });
            }
            else {
              restart(timeout);
            }
          }
          catch (Exception ex) {
            LOG.error(ex);
          }
        }
      }

      private boolean notificationsComponentIsLoaded() {
        return ApplicationManager.getApplication().runReadAction(new Computable<NotificationsConfiguration>() {
          @Override
          public NotificationsConfiguration compute() {
            return NotificationsConfiguration.getNotificationsConfiguration();
          }
        }) != null;
      }

      private void restart(long timeout) {
        JobScheduler.getScheduler().schedule(this, timeout, TimeUnit.SECONDS);
      }
    }, 1, TimeUnit.SECONDS);
  }

  private void checkPowerSaveMode() {
    if (PowerSaveMode.isEnabled()) {
      final String ignoreKey = "ignore.power.save.mode";
      String message = "Power save mode is on. Code insight and other background tasks are disabled." +
                       "<br/><a href=\"ignore\">Do not show again</a>" +
                       "<br/><a href=\"turnOff\">Disable Power Save Mode</a>";

      showNotification(ignoreKey, message, new HyperlinkAdapter() {
        @Override
        protected void hyperlinkActivated(HyperlinkEvent e) {
          final String description = e.getDescription();
          if ("ignore".equals(description)) {
            myProperties.setValue(ignoreKey, "true");
          }
          else if ("turnOff".equals(description)) {
            PowerSaveMode.setEnabled(false);
          }
        }
      });
    }
  }
}