// Copyright (C) 2008 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.httpd.rpc.patch;

import com.google.gerrit.common.data.ReviewerResult;
import com.google.gerrit.common.data.ApprovalSummary;
import com.google.gerrit.common.data.ApprovalSummarySet;
import com.google.gerrit.common.data.ApprovalTypes;
import com.google.gerrit.common.data.PatchDetailService;
import com.google.gerrit.common.data.PatchScript;
import com.google.gerrit.common.data.PatchScriptSettings;
import com.google.gerrit.common.errors.NoSuchEntityException;
import com.google.gerrit.httpd.rpc.BaseServiceImplementation;
import com.google.gerrit.httpd.rpc.Handler;
import com.google.gerrit.reviewdb.Account;
import com.google.gerrit.reviewdb.AccountPatchReview;
import com.google.gerrit.reviewdb.ApprovalCategory;
import com.google.gerrit.reviewdb.ApprovalCategoryValue;
import com.google.gerrit.reviewdb.Change;
import com.google.gerrit.reviewdb.Patch;
import com.google.gerrit.reviewdb.PatchLineComment;
import com.google.gerrit.reviewdb.PatchSet;
import com.google.gerrit.reviewdb.PatchSetApproval;
import com.google.gerrit.reviewdb.ReviewDb;
import com.google.gerrit.reviewdb.Patch.Key;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.account.AccountInfoCacheFactory;
import com.google.gerrit.server.patch.PublishComments;
import com.google.gerrit.server.project.ChangeControl;
import com.google.gerrit.server.project.NoSuchChangeException;
import com.google.gerrit.server.workflow.FunctionState;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwtjsonrpc.client.VoidResult;
import com.google.gwtorm.client.OrmException;
import com.google.inject.Inject;
import com.google.inject.Provider;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

class PatchDetailServiceImpl extends BaseServiceImplementation implements
    PatchDetailService {
  private final ApprovalTypes approvalTypes;

  private final AccountInfoCacheFactory.Factory accountInfoCacheFactory;
  private final AddReviewer.Factory addReviewerFactory;
  private final ChangeControl.Factory changeControlFactory;
  private final RemoveReviewer.Factory removeReviewerFactory;
  private final FunctionState.Factory functionStateFactory;
  private final PublishComments.Factory publishCommentsFactory;
  private final PatchScriptFactory.Factory patchScriptFactoryFactory;
  private final SaveDraft.Factory saveDraftFactory;

  @Inject
  PatchDetailServiceImpl(final Provider<ReviewDb> schema,
      final Provider<CurrentUser> currentUser,
      final ApprovalTypes approvalTypes,
      final AccountInfoCacheFactory.Factory accountInfoCacheFactory,
      final AddReviewer.Factory addReviewerFactory,
      final RemoveReviewer.Factory removeReviewerFactory,
      final ChangeControl.Factory changeControlFactory,
      final FunctionState.Factory functionStateFactory,
      final PatchScriptFactory.Factory patchScriptFactoryFactory,
      final PublishComments.Factory publishCommentsFactory,
      final SaveDraft.Factory saveDraftFactory) {
    super(schema, currentUser);
    this.approvalTypes = approvalTypes;

    this.accountInfoCacheFactory = accountInfoCacheFactory;
    this.addReviewerFactory = addReviewerFactory;
    this.removeReviewerFactory = removeReviewerFactory;
    this.changeControlFactory = changeControlFactory;
    this.functionStateFactory = functionStateFactory;
    this.patchScriptFactoryFactory = patchScriptFactoryFactory;
    this.publishCommentsFactory = publishCommentsFactory;
    this.saveDraftFactory = saveDraftFactory;
  }

  public void patchScript(final Patch.Key patchKey, final PatchSet.Id psa,
      final PatchSet.Id psb, final PatchScriptSettings s,
      final AsyncCallback<PatchScript> callback) {
    if (psb == null) {
      callback.onFailure(new NoSuchEntityException());
      return;
    }
    patchScriptFactoryFactory.create(patchKey, psa, psb, s).to(callback);
  }

  public void saveDraft(final PatchLineComment comment,
      final AsyncCallback<PatchLineComment> callback) {
    saveDraftFactory.create(comment).to(callback);
  }

  public void deleteDraft(final PatchLineComment.Key commentKey,
      final AsyncCallback<VoidResult> callback) {
    run(callback, new Action<VoidResult>() {
      public VoidResult run(ReviewDb db) throws OrmException, Failure {
        final PatchLineComment comment = db.patchComments().get(commentKey);
        if (comment == null) {
          throw new Failure(new NoSuchEntityException());
        }
        if (!getAccountId().equals(comment.getAuthor())) {
          throw new Failure(new NoSuchEntityException());
        }
        if (comment.getStatus() != PatchLineComment.Status.DRAFT) {
          throw new Failure(new IllegalStateException("Comment published"));
        }
        db.patchComments().delete(Collections.singleton(comment));
        return VoidResult.INSTANCE;
      }
    });
  }

  public void publishComments(final PatchSet.Id psid, final String msg,
      final Set<ApprovalCategoryValue.Id> tags,
      final AsyncCallback<VoidResult> cb) {
    Handler.wrap(publishCommentsFactory.create(psid, msg, tags)).to(cb);
  }

  /**
   * Update the reviewed status for the file by user @code{account}
   */
  public void setReviewedByCurrentUser(final Key patchKey,
      final boolean reviewed, AsyncCallback<VoidResult> callback) {
    run(callback, new Action<VoidResult>() {
      public VoidResult run(ReviewDb db) throws OrmException {
        Account.Id account = getAccountId();
        AccountPatchReview.Key key =
            new AccountPatchReview.Key(patchKey, account);
        AccountPatchReview apr = db.accountPatchReviews().get(key);
        if (apr == null && reviewed) {
          db.accountPatchReviews().insert(
              Collections.singleton(new AccountPatchReview(patchKey, account)));
        } else if (apr != null && !reviewed) {
          db.accountPatchReviews().delete(Collections.singleton(apr));
        }
        return VoidResult.INSTANCE;
      }
    });
  }

  public void addReviewers(final Change.Id id, final List<String> reviewers,
      final AsyncCallback<ReviewerResult> callback) {
    addReviewerFactory.create(id, reviewers).to(callback);
  }

  public void removeReviewer(final Change.Id id, final Account.Id reviewerId,
      final AsyncCallback<ReviewerResult> callback) {
    removeReviewerFactory.create(id, reviewerId).to(callback);
  }

  public void userApprovals(final Set<Change.Id> cids, final Account.Id aid,
      final AsyncCallback<ApprovalSummarySet> callback) {
    run(callback, new Action<ApprovalSummarySet>() {
      public ApprovalSummarySet run(ReviewDb db) throws OrmException {
        final Map<Change.Id, ApprovalSummary> approvals =
            new HashMap<Change.Id, ApprovalSummary>();
        final AccountInfoCacheFactory aicFactory =
            accountInfoCacheFactory.create();

        aicFactory.want(aid);
        for (final Change.Id id : cids) {
          try {
            final ChangeControl cc = changeControlFactory.validateFor(id);
            final Change change = cc.getChange();
            final PatchSet.Id ps_id = change.currentPatchSetId();
            final Map<ApprovalCategory.Id, PatchSetApproval> psas =
                new HashMap<ApprovalCategory.Id, PatchSetApproval>();
            final FunctionState fs =
                functionStateFactory.create(change, ps_id, psas.values());

            for (final PatchSetApproval ca : db.patchSetApprovals()
                .byPatchSetUser(ps_id, aid)) {
              final ApprovalCategory.Id category = ca.getCategoryId();
              if (change.getStatus().isOpen()) {
                fs.normalize(approvalTypes.getApprovalType(category), ca);
              }
              if (ca.getValue() == 0
                  || ApprovalCategory.SUBMIT.equals(category)) {
                continue;
              }
              psas.put(category, ca);
            }

            approvals.put(id, new ApprovalSummary(psas.values()));
          } catch (NoSuchChangeException nsce) {
            /*
             * The user has no access to see this change, so we simply do not
             * provide any details about it.
             */
          }
        }
        return new ApprovalSummarySet(aicFactory.create(), approvals);
      }
    });
  }

  public void strongestApprovals(final Set<Change.Id> cids,
      final AsyncCallback<ApprovalSummarySet> callback) {
    run(callback, new Action<ApprovalSummarySet>() {
      public ApprovalSummarySet run(ReviewDb db) throws OrmException {
        final Map<Change.Id, ApprovalSummary> approvals =
            new HashMap<Change.Id, ApprovalSummary>();
        final AccountInfoCacheFactory aicFactory =
            accountInfoCacheFactory.create();

        for (final Change.Id id : cids) {
          try {
            final ChangeControl cc = changeControlFactory.validateFor(id);
            final Change change = cc.getChange();
            final PatchSet.Id ps_id = change.currentPatchSetId();
            final Map<ApprovalCategory.Id, PatchSetApproval> psas =
                new HashMap<ApprovalCategory.Id, PatchSetApproval>();
            final FunctionState fs =
                functionStateFactory.create(change, ps_id, psas.values());

            for (PatchSetApproval ca : db.patchSetApprovals().byPatchSet(ps_id)) {
              final ApprovalCategory.Id category = ca.getCategoryId();
              if (change.getStatus().isOpen()) {
                fs.normalize(approvalTypes.getApprovalType(category), ca);
              }
              if (ca.getValue() == 0
                  || ApprovalCategory.SUBMIT.equals(category)) {
                continue;
              }
              boolean keep = true;
              if (psas.containsKey(category)) {
                final short oldValue = psas.get(category).getValue();
                final short newValue = ca.getValue();
                keep =
                    (Math.abs(oldValue) < Math.abs(newValue))
                        || ((Math.abs(oldValue) == Math.abs(newValue) && (newValue < oldValue)));
              }
              if (keep) {
                aicFactory.want(ca.getAccountId());
                psas.put(category, ca);
              }
            }

            approvals.put(id, new ApprovalSummary(psas.values()));
          } catch (NoSuchChangeException nsce) {
            /*
             * The user has no access to see this change, so we simply do not
             * provide any details about it.
             */
          }
        }

        return new ApprovalSummarySet(aicFactory.create(), approvals);
      }
    });
  }
}