// Copyright (C) 2021 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.approval;

import com.google.gerrit.entities.Account;
import com.google.gerrit.entities.PatchSet;
import com.google.gerrit.entities.PatchSetApproval;
import com.google.gerrit.entities.PatchSetApproval.UUID;
import com.google.inject.Singleton;
import java.security.MessageDigest;
import java.time.Instant;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.ObjectId;

/**
 * Default implementation of {@link
 * com.google.gerrit.server.approval.PatchSetApprovalUuidGenerator}.
 */
@Singleton
public class PatchSetApprovalUuidGeneratorImpl implements PatchSetApprovalUuidGenerator {
  @Override
  public UUID get(
      PatchSet.Id patchSetId, Account.Id accountId, String label, short value, Instant granted) {
    MessageDigest md = Constants.newMessageDigest();
    md.update(
        Constants.encode("patchSetId " + patchSetId.getCommaSeparatedChangeAndPatchSetId() + "\n"));
    md.update(Constants.encode("accountId " + accountId + "\n"));
    md.update(Constants.encode("label " + label + "\n"));
    md.update(Constants.encode("value " + value + "\n"));
    md.update(Constants.encode("granted " + granted.toEpochMilli() + "\n"));
    md.update(Constants.encode(String.valueOf(Math.random())));
    return PatchSetApproval.uuid(ObjectId.fromRaw(md.digest()).name());
  }
}