// 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.server.ssh;

import com.google.gerrit.client.data.ProjectCache;
import com.google.gerrit.client.reviewdb.Account;
import com.google.gerrit.client.reviewdb.ApprovalCategory;
import com.google.gerrit.client.reviewdb.Project;
import com.google.gerrit.client.reviewdb.ProjectRight;
import com.google.gerrit.client.rpc.Common;
import com.google.gerrit.git.InvalidRepositoryException;

import org.kohsuke.args4j.Argument;
import org.spearce.jgit.lib.Repository;

import java.io.IOException;

abstract class AbstractGitCommand extends AbstractCommand {
  @Argument(index = 0, metaVar = "PROJECT.git", required = true, usage = "project name")
  private String reqProjName;

  protected Repository repo;
  protected ProjectCache.Entry cachedProj;
  protected Project proj;
  protected Account userAccount;

  protected boolean isGerrit() {
    return getName().startsWith("gerrit-");
  }

  @Override
  protected void preRun() throws Failure {
    super.preRun();
    openReviewDb();
  }

  @Override
  protected final void run() throws IOException, Failure {
    String projectName = reqProjName;
    if (projectName.endsWith(".git")) {
      // Be nice and drop the trailing ".git" suffix, which we never keep
      // in our database, but clients might mistakenly provide anyway.
      //
      projectName = projectName.substring(0, projectName.length() - 4);
    }
    if (projectName.startsWith("/")) {
      // Be nice and drop the leading "/" if supplied by an absolute path.
      // We don't have a file system hierarchy, just a flat namespace in
      // the database's Project entities. We never encode these with a
      // leading '/' but users might accidentally include them in Git URLs.
      //
      projectName = projectName.substring(1);
    }

    cachedProj = Common.getProjectCache().get(new Project.NameKey(projectName));
    if (cachedProj == null) {
      throw new Failure(1, "fatal: '" + reqProjName + "': not a Gerrit project");
    }

    proj = cachedProj.getProject();
    if (ProjectRight.WILD_PROJECT.equals(proj.getId())) {
      throw new Failure(1, "fatal: '" + reqProjName + "': not a valid project",
          new IllegalArgumentException("Cannot access the wildcard project"));
    }
    if (!canRead(cachedProj)) {
      throw new Failure(1, "fatal: '" + reqProjName + "': unknown project",
          new SecurityException("Account lacks Read permission"));
    }

    try {
      repo = getRepositoryCache().get(proj.getName());
    } catch (InvalidRepositoryException e) {
      throw new Failure(1, "fatal: '" + reqProjName + "': not a git archive", e);
    }

    userAccount = Common.getAccountCache().get(getAccountId(), db);
    if (userAccount == null) {
      throw new Failure(1, "fatal: cannot query user database",
          new IllegalStateException("Account record no longer in database"));
    }

    runImpl();
  }

  protected boolean canPerform(final ApprovalCategory.Id actionId,
      final short val) {
    return canPerform(cachedProj, actionId, val);
  }

  protected abstract void runImpl() throws IOException, Failure;
}