/*
 * Copyright 2000-2009 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.vcs.changes;

import com.intellij.openapi.application.ApplicationManager;
import com.intellij.openapi.components.ProjectComponent;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.progress.ProcessCanceledException;
import com.intellij.openapi.project.DumbAwareRunnable;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.startup.StartupManager;
import com.intellij.openapi.util.Computable;
import com.intellij.openapi.util.Ref;
import com.intellij.openapi.vcs.AbstractVcs;
import com.intellij.openapi.vcs.FilePath;
import com.intellij.openapi.vcs.ProjectLevelVcsManager;
import com.intellij.openapi.vcs.VcsRoot;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.util.Consumer;
import com.intellij.util.ReflectionUtil;
import org.jetbrains.annotations.NonNls;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.ArrayList;
import java.util.Collection;

/**
 * @author max
 */
public class VcsDirtyScopeManagerImpl extends VcsDirtyScopeManager implements ProjectComponent {
  private static final Logger LOG = Logger.getInstance("#com.intellij.openapi.vcs.changes.VcsDirtyScopeManagerImpl");

  private final Project myProject;
  private final ChangeListManager myChangeListManager;
  private final ProjectLevelVcsManager myVcsManager;

  private final DirtBuilder myDirtBuilder;
  private final VcsGuess myGuess;
  private final SynchronizedLife myLife;

  private final MyProgressHolder myProgressHolder;

  public VcsDirtyScopeManagerImpl(Project project, ChangeListManager changeListManager, ProjectLevelVcsManager vcsManager) {
    myProject = project;
    myChangeListManager = changeListManager;
    myVcsManager = vcsManager;

    myLife = new SynchronizedLife();
    myGuess = new VcsGuess(myProject);
    myDirtBuilder = new DirtBuilder(myGuess);

    myProgressHolder = new MyProgressHolder();
    ((ChangeListManagerImpl) myChangeListManager).setDirtyScopeManager(this);
  }

  public void projectOpened() {
    if (ApplicationManager.getApplication().isUnitTestMode()) {
      myLife.born();
      final AbstractVcs[] vcss = myVcsManager.getAllActiveVcss();
      if (vcss.length > 0) {
        markEverythingDirty();
      }
    }
    else {
      StartupManager.getInstance(myProject).registerPostStartupActivity(new DumbAwareRunnable() {
        public void run() {
          myLife.born();
          markEverythingDirty();
        }
      });
    }
  }

  public void suspendMe() {
    myLife.suspendMe();
  }

  public void reanimate() {
    final Ref<Boolean> wasNotEmptyRef = new Ref<Boolean>();
    myLife.releaseMe(new Runnable() {
      public void run() {
        wasNotEmptyRef.set(! myDirtBuilder.isEmpty());
      }
    });
    if (Boolean.TRUE.equals(wasNotEmptyRef.get())) {
      myChangeListManager.scheduleUpdate();
    }
  }

  public void markEverythingDirty() {
    if ((! myProject.isOpen()) || myProject.isDisposed() || myVcsManager.getAllActiveVcss().length == 0) return;

    if (LOG.isDebugEnabled()) {
      LOG.debug("everything dirty: " + ReflectionUtil.findCallerClass(2));
    }

    final LifeDrop lifeDrop = myLife.doIfAlive(new Runnable() {
      public void run() {
        myDirtBuilder.everythingDirty();
      }
    });

    if (lifeDrop.isDone() && !lifeDrop.isSuspened()) {
      myChangeListManager.scheduleUpdate();
    }
  }

  public void projectClosed() {
    killSelf();
  }

  @NotNull @NonNls
  public String getComponentName() {
    return "VcsDirtyScopeManager";
  }

  public void initComponent() {}

  private void killSelf() {
    myLife.kill(new Runnable() {
      public void run() {
        myDirtBuilder.reset();
      }
    });
  }

  public void disposeComponent() {
    killSelf();
  }

  private void convertPaths(@Nullable final Collection<FilePath> from, final Collection<FilePathUnderVcs> to) {
    if (from != null) {
      for (FilePath fp : from) {
        final AbstractVcs vcs = myGuess.getVcsForDirty(fp);
        if (vcs != null) {
          to.add(new FilePathUnderVcs(fp, vcs));
        }
      }
    }
  }

  public void filePathsDirty(@Nullable final Collection<FilePath> filesDirty, @Nullable final Collection<FilePath> dirsRecursivelyDirty) {
    try {
      final ArrayList<FilePathUnderVcs> filesConverted = filesDirty == null ? null : new ArrayList<FilePathUnderVcs>(filesDirty.size());
      final ArrayList<FilePathUnderVcs> dirsConverted = dirsRecursivelyDirty == null ? null : new ArrayList<FilePathUnderVcs>(dirsRecursivelyDirty.size());

      ApplicationManager.getApplication().runReadAction(new Runnable() {
        public void run() {
          convertPaths(filesDirty, filesConverted);
          convertPaths(dirsRecursivelyDirty, dirsConverted);
        }
      });
      final boolean haveStuff = filesConverted != null && ! filesConverted.isEmpty()
                                || dirsConverted != null && ! dirsConverted.isEmpty();
      if (! haveStuff) return;

      if (LOG.isDebugEnabled()) {
        LOG.debug("paths dirty: " + filesConverted + "; " + dirsConverted + "; " + ReflectionUtil.findCallerClass(2));
      }

      takeDirt(new Consumer<DirtBuilder>() {
        public void consume(final DirtBuilder dirt) {
          if (filesConverted != null) {
            for (FilePathUnderVcs root : filesConverted) {
              dirt.addDirtyFile(root);
            }
          }
          if (dirsConverted != null) {
            for (FilePathUnderVcs root : dirsConverted) {
              dirt.addDirtyDirRecursively(root);
            }
          }
        }
      });
    } catch (ProcessCanceledException ignore) {
    }
  }

  private void takeDirt(final Consumer<DirtBuilder> filler) {
    final Ref<Boolean> wasNotEmptyRef = new Ref<Boolean>();
    final Runnable runnable = new Runnable() {
      public void run() {
        filler.consume(myDirtBuilder);
        wasNotEmptyRef.set(!myDirtBuilder.isEmpty());
      }
    };
    final LifeDrop lifeDrop = myLife.doIfAlive(runnable);

    if (lifeDrop.isDone() && !lifeDrop.isSuspened() && Boolean.TRUE.equals(wasNotEmptyRef.get())) {
      myChangeListManager.scheduleUpdate();
    }
  }

  private void convert(@Nullable final Collection<VirtualFile> from, final Collection<VcsRoot> to) {
    if (from != null) {
      for (VirtualFile vf : from) {
        final AbstractVcs vcs = myGuess.getVcsForDirty(vf);
        if (vcs != null) {
          to.add(new VcsRoot(vcs, vf));
        }
      }
    }
  }

  public void filesDirty(@Nullable final Collection<VirtualFile> filesDirty, @Nullable final Collection<VirtualFile> dirsRecursivelyDirty) {
    try {
      final ArrayList<VcsRoot> filesConverted = filesDirty == null ? null : new ArrayList<VcsRoot>(filesDirty.size());
      final ArrayList<VcsRoot> dirsConverted = dirsRecursivelyDirty == null ? null : new ArrayList<VcsRoot>(dirsRecursivelyDirty.size());

      ApplicationManager.getApplication().runReadAction(new Runnable() {
        public void run() {
          convert(filesDirty, filesConverted);
          convert(dirsRecursivelyDirty, dirsConverted);
        }
      });
      final boolean haveStuff = filesConverted != null && ! filesConverted.isEmpty() || dirsConverted != null && ! dirsConverted.isEmpty();
      if (! haveStuff) return;

      if (LOG.isDebugEnabled()) {
        LOG.debug("files dirty: " + filesConverted + "; " + dirsConverted + "; " + ReflectionUtil.findCallerClass(2));
      }

      takeDirt(new Consumer<DirtBuilder>() {
        public void consume(final DirtBuilder dirt) {
          if (filesConverted != null) {
            for (VcsRoot root : filesConverted) {
              dirt.addDirtyFile(root);
            }
          }
          if (dirsConverted != null) {
            for (VcsRoot root : dirsConverted) {
              dirt.addDirtyDirRecursively(root);
            }
          }
        }
      });
    } catch (ProcessCanceledException ignore) {
    }
  }

  public void fileDirty(@NotNull final VirtualFile file) {
    try {
      final AbstractVcs vcs = myGuess.getVcsForDirty(file);
      if (vcs == null) return;
      if (LOG.isDebugEnabled()) {
        LOG.debug("file dirty: " + file + "; " + ReflectionUtil.findCallerClass(2));
      }
      final VcsRoot root = new VcsRoot(vcs, file);
      takeDirt(new Consumer<DirtBuilder>() {
        public void consume(DirtBuilder dirtBuilder) {
          dirtBuilder.addDirtyFile(root);
        }
      });
    } catch (ProcessCanceledException ignore) {
    }
  }

  public void fileDirty(@NotNull final FilePath file) {
    try {
      final AbstractVcs vcs = myGuess.getVcsForDirty(file);
      if (vcs == null) return;
      if (LOG.isDebugEnabled()) {
        LOG.debug("file dirty: " + file + "; " + ReflectionUtil.findCallerClass(1));
      }
      final FilePathUnderVcs root = new FilePathUnderVcs(file, vcs);
      takeDirt(new Consumer<DirtBuilder>() {
        public void consume(DirtBuilder dirtBuilder) {
          dirtBuilder.addDirtyFile(root);
        }
      });
    } catch (ProcessCanceledException ignore) {
    }
  }

  public void dirDirtyRecursively(final VirtualFile dir, final boolean scheduleUpdate) {
    dirDirtyRecursively(dir);
  }

  public void dirDirtyRecursively(final VirtualFile dir) {
    try {
      final AbstractVcs vcs = myGuess.getVcsForDirty(dir);
      if (vcs == null) return;
      if (LOG.isDebugEnabled()) {
        LOG.debug("dir dirty recursively: " + dir + "; " + ReflectionUtil.findCallerClass(2));
      }
      final VcsRoot root = new VcsRoot(vcs, dir);
      takeDirt(new Consumer<DirtBuilder>() {
        public void consume(DirtBuilder dirtBuilder) {
          dirtBuilder.addDirtyDirRecursively(root);
        }
      });
    } catch (ProcessCanceledException ignore) {
    }
  }

  public void dirDirtyRecursively(final FilePath path) {
    try {
      final AbstractVcs vcs = myGuess.getVcsForDirty(path);
      if (vcs == null) return;
      if (LOG.isDebugEnabled()) {
        LOG.debug("dir dirty recursively: " + path + "; " + ReflectionUtil.findCallerClass(2));
      }
      final FilePathUnderVcs root = new FilePathUnderVcs(path, vcs);
      takeDirt(new Consumer<DirtBuilder>() {
        public void consume(DirtBuilder dirtBuilder) {
          dirtBuilder.addDirtyDirRecursively(root);
        }
      });
    } catch (ProcessCanceledException ignore) {
    }
  }

  private class MyProgressHolder {
    private VcsInvalidated myInProgressState;
    private DirtBuilderReader myInProgressDirtBuilder;

    public MyProgressHolder() {
      myInProgressDirtBuilder = new DirtBuilder(myGuess);
      myInProgressState = null;
    }

    public void takeNext(final DirtBuilderReader dirtBuilder) {
      myInProgressDirtBuilder = dirtBuilder;
      myInProgressState = null;
    }

    private MyProgressHolder(final DirtBuilderReader dirtBuilder, final VcsInvalidated vcsInvalidated) {
      myInProgressDirtBuilder = dirtBuilder;
      myInProgressState = vcsInvalidated;
    }

    public VcsInvalidated calculateInvalidated() {
      if (myInProgressDirtBuilder != null) {
        return ApplicationManager.getApplication().runReadAction(new Computable<VcsInvalidated>() {
          public VcsInvalidated compute() {
            final Scopes scopes = new Scopes(myProject, myGuess);
            scopes.takeDirt(myInProgressDirtBuilder);
            return scopes.retrieveAndClear();
          }
        });
      }
      return myInProgressState;
    }

    public void takeInvalidated(final VcsInvalidated invalidated) {
      myInProgressState = invalidated;
      myInProgressDirtBuilder = null;
    }

    public void processed() {
      myInProgressState = null;
      myInProgressDirtBuilder = null;
    }

    public MyProgressHolder copy() {
      return new MyProgressHolder(myInProgressDirtBuilder, myInProgressState);
    }
  }

  @Nullable
  public VcsInvalidated retrieveScopes() {
    final LifeDrop lifeDrop = myLife.doIfAlive(new Runnable() {
      public void run() {
        myProgressHolder.takeNext(new DirtBuilder(myDirtBuilder));
        myDirtBuilder.reset();
      }
    });

    if (lifeDrop.isDone()) {
      final VcsInvalidated invalidated = myProgressHolder.calculateInvalidated();

      myLife.doIfAlive(new Runnable() {
        public void run() {
          myProgressHolder.takeInvalidated(invalidated);
        }
      });
      return invalidated;
    }
    return null;
  }

  public void changesProcessed() {
    myLife.doIfAlive(new Runnable() {
      public void run() {
        myProgressHolder.processed();
      }
    });
  }

  @NotNull
  @Override
  public Collection<FilePath> whatFilesDirty(@NotNull final Collection<FilePath> files) {
    final Collection<FilePath> result = new ArrayList<FilePath>();
    final Ref<MyProgressHolder> inProgressHolderRef = new Ref<MyProgressHolder>();
    final Ref<MyProgressHolder> currentHolderRef = new Ref<MyProgressHolder>();

    myLife.doIfAlive(new Runnable() {
      public void run() {
        inProgressHolderRef.set(myProgressHolder.copy());
        currentHolderRef.set(new MyProgressHolder(new DirtBuilder(myDirtBuilder), null));
      }
    });
    final VcsInvalidated inProgressInvalidated = inProgressHolderRef.get() == null ? null : inProgressHolderRef.get().calculateInvalidated();
    final VcsInvalidated currentInvalidated = currentHolderRef.get() == null ? null : currentHolderRef.get().calculateInvalidated();
    for (FilePath fp : files) {
      if (inProgressInvalidated != null && inProgressInvalidated.isFileDirty(fp)
          || currentInvalidated != null && currentInvalidated.isFileDirty(fp)) {
        result.add(fp);
      }
    }
    return result;
  }

  private String toStringScopes(final VcsInvalidated vcsInvalidated) {
    final StringBuilder sb = new StringBuilder();
    sb.append("is everything dirty: ").append(vcsInvalidated.isEverythingDirty()).append(";\n");
    for (VcsDirtyScope scope : vcsInvalidated.getScopes()) {
      sb.append("|\nFiles: ");
      for (FilePath path : scope.getDirtyFiles()) {
        sb.append(path).append('\n');
      }
      sb.append("\nDirs: ");
      for (FilePath filePath : scope.getRecursivelyDirtyDirectories()) {
        sb.append(filePath).append('\n');
      }
    }
    sb.append("-------------");
    return sb.toString();
  }

  private static class LifeDrop {
    private final boolean myDone;
    private final boolean mySuspened;

    private LifeDrop(boolean done, boolean suspened) {
      myDone = done;
      mySuspened = suspened;
    }

    public boolean isDone() {
      return myDone;
    }

    public boolean isSuspened() {
      return mySuspened;
    }
  }

  private static class SynchronizedLife {
    private LifeStages myStage;
    private final Object myLock;
    private boolean mySuspended;

    private SynchronizedLife() {
      myStage = LifeStages.NOT_BORN;
      myLock = new Object();
    }

    public void born() {
      synchronized (myLock) {
        myStage = LifeStages.ALIVE;
      }
    }

    public void kill(Runnable runnable) {
      synchronized (myLock) {
        myStage = LifeStages.DEAD;
        runnable.run();
      }
    }

    public void suspendMe() {
      synchronized (myLock) {
        if (LifeStages.ALIVE.equals(myStage)) {
          mySuspended = true;
        }
      }
    }

    public void releaseMe(final Runnable runnable) {
      synchronized (myLock) {
        if (LifeStages.ALIVE.equals(myStage)) {
          mySuspended = false;
          runnable.run();
        }
      }
    }

    public LifeDrop doIfAliveAndNotSuspended(final Runnable runnable) {
      synchronized (myLock) {
        synchronized (myLock) {
          if (LifeStages.ALIVE.equals(myStage) && ! mySuspended) {
            runnable.run();
            return new LifeDrop(true, mySuspended);
          }
          return new LifeDrop(false, mySuspended);
        }
      }
    }

    // allow work under inner lock: inner class, not wide scope
    public LifeDrop doIfAlive(final Runnable runnable) {
      synchronized (myLock) {
        if (LifeStages.ALIVE.equals(myStage)) {
          runnable.run();
          return new LifeDrop(true, mySuspended);
        }
        return new LifeDrop(false, mySuspended);
      }
    }

    private static enum LifeStages {
      NOT_BORN,
      ALIVE,
      DEAD
    }
  }
}