// Copyright (C) 2013 The Android Open Source Project
//
// 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.google.gerrit.server.api.changes;

import com.google.common.collect.ImmutableSet;
import com.google.gerrit.common.errors.EmailException;
import com.google.gerrit.extensions.api.changes.ChangeApi;
import com.google.gerrit.extensions.api.changes.Changes;
import com.google.gerrit.extensions.api.changes.CherryPickInput;
import com.google.gerrit.extensions.api.changes.CommentApi;
import com.google.gerrit.extensions.api.changes.DraftApi;
import com.google.gerrit.extensions.api.changes.DraftInput;
import com.google.gerrit.extensions.api.changes.FileApi;
import com.google.gerrit.extensions.api.changes.RebaseInput;
import com.google.gerrit.extensions.api.changes.ReviewInput;
import com.google.gerrit.extensions.api.changes.RevisionApi;
import com.google.gerrit.extensions.api.changes.SubmitInput;
import com.google.gerrit.extensions.client.SubmitType;
import com.google.gerrit.extensions.common.ActionInfo;
import com.google.gerrit.extensions.common.CommentInfo;
import com.google.gerrit.extensions.common.FileInfo;
import com.google.gerrit.extensions.common.MergeableInfo;
import com.google.gerrit.extensions.common.TestSubmitRuleInput;
import com.google.gerrit.extensions.restapi.BinaryResult;
import com.google.gerrit.extensions.restapi.IdString;
import com.google.gerrit.extensions.restapi.RestApiException;
import com.google.gerrit.extensions.restapi.RestModifyView;
import com.google.gerrit.server.change.CherryPick;
import com.google.gerrit.server.change.Comments;
import com.google.gerrit.server.change.CreateDraftComment;
import com.google.gerrit.server.change.DeleteDraftPatchSet;
import com.google.gerrit.server.change.DraftComments;
import com.google.gerrit.server.change.FileResource;
import com.google.gerrit.server.change.Files;
import com.google.gerrit.server.change.GetPatch;
import com.google.gerrit.server.change.GetRevisionActions;
import com.google.gerrit.server.change.ListRevisionComments;
import com.google.gerrit.server.change.ListRevisionDrafts;
import com.google.gerrit.server.change.Mergeable;
import com.google.gerrit.server.change.PostReview;
import com.google.gerrit.server.change.PublishDraftPatchSet;
import com.google.gerrit.server.change.Rebase;
import com.google.gerrit.server.change.RebaseUtil;
import com.google.gerrit.server.change.Reviewed;
import com.google.gerrit.server.change.RevisionResource;
import com.google.gerrit.server.change.Submit;
import com.google.gerrit.server.change.TestSubmitType;
import com.google.gerrit.server.git.GitRepositoryManager;
import com.google.gerrit.server.git.UpdateException;
import com.google.gerrit.server.project.NoSuchChangeException;
import com.google.gwtorm.server.OrmException;
import com.google.inject.Inject;
import com.google.inject.assistedinject.Assisted;

import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevWalk;

import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.Set;

class RevisionApiImpl implements RevisionApi {
  interface Factory {
    RevisionApiImpl create(RevisionResource r);
  }

  private final GitRepositoryManager repoManager;
  private final Changes changes;
  private final CherryPick cherryPick;
  private final DeleteDraftPatchSet deleteDraft;
  private final Rebase rebase;
  private final RebaseUtil rebaseUtil;
  private final Submit submit;
  private final PublishDraftPatchSet publish;
  private final Reviewed.PutReviewed putReviewed;
  private final Reviewed.DeleteReviewed deleteReviewed;
  private final RevisionResource revision;
  private final Files files;
  private final Files.ListFiles listFiles;
  private final GetPatch getPatch;
  private final PostReview review;
  private final Mergeable mergeable;
  private final FileApiImpl.Factory fileApi;
  private final ListRevisionComments listComments;
  private final ListRevisionDrafts listDrafts;
  private final CreateDraftComment createDraft;
  private final DraftComments drafts;
  private final DraftApiImpl.Factory draftFactory;
  private final Comments comments;
  private final CommentApiImpl.Factory commentFactory;
  private final GetRevisionActions revisionActions;
  private final TestSubmitType testSubmitType;
  private final TestSubmitType.Get getSubmitType;

  @Inject
  RevisionApiImpl(GitRepositoryManager repoManager,
      Changes changes,
      CherryPick cherryPick,
      DeleteDraftPatchSet deleteDraft,
      Rebase rebase,
      RebaseUtil rebaseUtil,
      Submit submit,
      PublishDraftPatchSet publish,
      Reviewed.PutReviewed putReviewed,
      Reviewed.DeleteReviewed deleteReviewed,
      Files files,
      Files.ListFiles listFiles,
      GetPatch getPatch,
      PostReview review,
      Mergeable mergeable,
      FileApiImpl.Factory fileApi,
      ListRevisionComments listComments,
      ListRevisionDrafts listDrafts,
      CreateDraftComment createDraft,
      DraftComments drafts,
      DraftApiImpl.Factory draftFactory,
      Comments comments,
      CommentApiImpl.Factory commentFactory,
      GetRevisionActions revisionActions,
      TestSubmitType testSubmitType,
      TestSubmitType.Get getSubmitType,
      @Assisted RevisionResource r) {
    this.repoManager = repoManager;
    this.changes = changes;
    this.cherryPick = cherryPick;
    this.deleteDraft = deleteDraft;
    this.rebase = rebase;
    this.rebaseUtil = rebaseUtil;
    this.review = review;
    this.submit = submit;
    this.publish = publish;
    this.files = files;
    this.putReviewed = putReviewed;
    this.deleteReviewed = deleteReviewed;
    this.listFiles = listFiles;
    this.getPatch = getPatch;
    this.mergeable = mergeable;
    this.fileApi = fileApi;
    this.listComments = listComments;
    this.listDrafts = listDrafts;
    this.createDraft = createDraft;
    this.drafts = drafts;
    this.draftFactory = draftFactory;
    this.comments = comments;
    this.commentFactory = commentFactory;
    this.revisionActions = revisionActions;
    this.testSubmitType = testSubmitType;
    this.getSubmitType = getSubmitType;
    this.revision = r;
  }

  @Override
  public void review(ReviewInput in) throws RestApiException {
    try {
      review.apply(revision, in);
    } catch (OrmException | UpdateException | IOException e) {
      throw new RestApiException("Cannot post review", e);
    }
  }

  @Override
  public void submit() throws RestApiException {
    SubmitInput in = new SubmitInput();
    submit(in);
  }

  @Override
  public void submit(SubmitInput in) throws RestApiException {
    try {
      submit.apply(revision, in);
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot submit change", e);
    }
  }

  @Override
  public void publish() throws RestApiException {
    try {
      publish.apply(revision, new PublishDraftPatchSet.Input());
    } catch (UpdateException e) {
      throw new RestApiException("Cannot publish draft patch set", e);
    }
  }

  @Override
  public void delete() throws RestApiException {
    try {
      deleteDraft.apply(revision, null);
    } catch (UpdateException e) {
      throw new RestApiException("Cannot delete draft ps", e);
    }
  }

  @Override
  public ChangeApi rebase() throws RestApiException {
    RebaseInput in = new RebaseInput();
    return rebase(in);
  }

  @Override
  public ChangeApi rebase(RebaseInput in) throws RestApiException {
    try {
      return changes.id(rebase.apply(revision, in)._number);
    } catch (OrmException | EmailException | UpdateException | IOException
        | NoSuchChangeException e) {
      throw new RestApiException("Cannot rebase ps", e);
    }
  }

  @Override
  public boolean canRebase() throws RestApiException {
    try (Repository repo = repoManager.openRepository(revision.getProject());
        RevWalk rw = new RevWalk(repo)) {
      return rebaseUtil.canRebase(
          revision.getPatchSet(), revision.getChange().getDest(), repo, rw);
    } catch (IOException e) {
      throw new RestApiException("Cannot check if rebase is possible", e);
    }
  }

  @Override
  public ChangeApi cherryPick(CherryPickInput in) throws RestApiException {
    try {
      return changes.id(cherryPick.apply(revision, in)._number);
    } catch (OrmException | IOException | UpdateException e) {
      throw new RestApiException("Cannot cherry pick", e);
    }
  }

  @Override
  public void setReviewed(String path, boolean reviewed) throws RestApiException {
    try {
      RestModifyView<FileResource, Reviewed.Input> view;
      if (reviewed) {
        view = putReviewed;
      } else {
        view = deleteReviewed;
      }
      view.apply(
          files.parse(revision, IdString.fromDecoded(path)),
          new Reviewed.Input());
    } catch (Exception e) {
      throw new RestApiException("Cannot update reviewed flag", e);
    }
  }

  @SuppressWarnings("unchecked")
  @Override
  public Set<String> reviewed() throws RestApiException {
    try {
      return ImmutableSet.copyOf((Iterable<String>) listFiles
          .setReviewed(true)
          .apply(revision).value());
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot list reviewed files", e);
    }
  }

  @Override
  public MergeableInfo mergeable() throws RestApiException {
    try {
      return mergeable.apply(revision);
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot check mergeability", e);
    }
  }

  @Override
  public MergeableInfo mergeableOtherBranches() throws RestApiException {
    try {
      mergeable.setOtherBranches(true);
      return mergeable.apply(revision);
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot check mergeability", e);
    }
  }

  @SuppressWarnings("unchecked")
  @Override
  public Map<String, FileInfo> files() throws RestApiException {
    try {
      return (Map<String, FileInfo>)listFiles.apply(revision).value();
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot retrieve files", e);
    }
  }

  @SuppressWarnings("unchecked")
  @Override
  public Map<String, FileInfo> files(String base) throws RestApiException {
    try {
      return (Map<String, FileInfo>) listFiles.setBase(base)
          .apply(revision).value();
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot retrieve files", e);
    }
  }

  @SuppressWarnings("unchecked")
  @Override
  public Map<String, FileInfo> files(int parentNum) throws RestApiException {
    try {
      return (Map<String, FileInfo>) listFiles.setParent(parentNum)
          .apply(revision).value();
    } catch (OrmException | IOException e) {
      throw new RestApiException("Cannot retrieve files", e);
    }
  }

  @Override
  public FileApi file(String path) throws RestApiException {
    try {
      return fileApi.create(files.parse(revision,
          IdString.fromDecoded(path)));
    } catch (IOException e) {
      throw new RestApiException("Cannot retrieve file", e);
    }
  }

  @Override
  public Map<String, List<CommentInfo>> comments() throws RestApiException {
    try {
      return listComments.apply(revision);
    } catch (OrmException e) {
      throw new RestApiException("Cannot retrieve comments", e);
    }
  }

  @Override
  public List<CommentInfo> commentsAsList() throws RestApiException {
    try {
      return listComments.getComments(revision);
    } catch (OrmException e) {
      throw new RestApiException("Cannot retrieve comments", e);
    }
  }

  @Override
  public Map<String, List<CommentInfo>> drafts() throws RestApiException {
    try {
      return listDrafts.apply(revision);
    } catch (OrmException e) {
      throw new RestApiException("Cannot retrieve drafts", e);
    }
  }

  @Override
  public List<CommentInfo> draftsAsList() throws RestApiException {
    try {
      return listDrafts.getComments(revision);
    } catch (OrmException e) {
      throw new RestApiException("Cannot retrieve drafts", e);
    }
  }

  @Override
  public DraftApi draft(String id) throws RestApiException {
    try {
      return draftFactory.create(drafts.parse(revision,
          IdString.fromDecoded(id)));
    } catch (OrmException e) {
      throw new RestApiException("Cannot retrieve draft", e);
    }
  }

  @Override
  public DraftApi createDraft(DraftInput in) throws RestApiException {
    try {
      String id = createDraft.apply(revision, in).value().id;
      // Reread change to pick up new notes refs.
      return changes.id(revision.getChange().getId().get())
          .revision(revision.getPatchSet().getId().get())
          .draft(id);
    } catch (UpdateException | OrmException e) {
      throw new RestApiException("Cannot create draft", e);
    }
  }

  @Override
  public CommentApi comment(String id) throws RestApiException {
    try {
      return commentFactory.create(comments.parse(revision,
          IdString.fromDecoded(id)));
    } catch (OrmException e) {
      throw new RestApiException("Cannot retrieve comment", e);
    }
  }

  @Override
  public BinaryResult patch() throws RestApiException {
    try {
      return getPatch.apply(revision);
    } catch (IOException e) {
      throw new RestApiException("Cannot get patch", e);
    }
  }

  @Override
  public Map<String, ActionInfo> actions() throws RestApiException {
    return revisionActions.apply(revision).value();
  }

  @Override
  public SubmitType submitType() throws RestApiException {
    try {
      return getSubmitType.apply(revision);
    } catch (OrmException e) {
      throw new RestApiException("Cannot get submit type", e);
    }
  }

  @Override
  public SubmitType testSubmitType(TestSubmitRuleInput in)
      throws RestApiException {
    try {
      return testSubmitType.apply(revision, in);
    } catch (OrmException e) {
      throw new RestApiException("Cannot test submit type", e);
    }
  }
}