// Copyright (C) 2014 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.pgm.init;

import static java.nio.charset.StandardCharsets.UTF_8;

import com.google.common.base.Strings;
import com.google.gerrit.common.TimeUtil;
import com.google.gerrit.extensions.client.AuthType;
import com.google.gerrit.pgm.init.api.ConsoleUI;
import com.google.gerrit.pgm.init.api.InitFlags;
import com.google.gerrit.pgm.init.api.InitStep;
import com.google.gerrit.reviewdb.client.Account;
import com.google.gerrit.reviewdb.client.AccountExternalId;
import com.google.gerrit.reviewdb.client.AccountGroup;
import com.google.gerrit.reviewdb.client.AccountGroupMember;
import com.google.gerrit.reviewdb.client.AccountGroupName;
import com.google.gerrit.reviewdb.client.AccountSshKey;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gwtorm.server.SchemaFactory;
import com.google.inject.Inject;

import org.apache.commons.validator.routines.EmailValidator;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Collections;

public class InitAdminUser implements InitStep {
  private final ConsoleUI ui;
  private final InitFlags flags;
  private final VersionedAuthorizedKeysOnInit.Factory authorizedKeysFactory;
  private SchemaFactory<ReviewDb> dbFactory;

  @Inject
  InitAdminUser(
      InitFlags flags,
      ConsoleUI ui,
      VersionedAuthorizedKeysOnInit.Factory authorizedKeysFactory) {
    this.flags = flags;
    this.ui = ui;
    this.authorizedKeysFactory = authorizedKeysFactory;
  }

  @Override
  public void run() {
  }

  @Inject(optional = true)
  void set(SchemaFactory<ReviewDb> dbFactory) {
    this.dbFactory = dbFactory;
  }

  @Override
  public void postRun() throws Exception {
    AuthType authType =
        flags.cfg.getEnum(AuthType.values(), "auth", null, "type", null);
    if (authType != AuthType.DEVELOPMENT_BECOME_ANY_ACCOUNT) {
      return;
    }

    try (ReviewDb db = dbFactory.open()) {
      if (db.accounts().anyAccounts().toList().isEmpty()) {
        ui.header("Gerrit Administrator");
        if (ui.yesno(true, "Create administrator user")) {
          Account.Id id = new Account.Id(db.nextAccountId());
          String username = ui.readString("admin", "username");
          String name = ui.readString("Administrator", "name");
          String httpPassword = ui.readString("secret", "HTTP password");
          AccountSshKey sshKey = readSshKey(id);
          String email = readEmail(sshKey);

          AccountExternalId extUser =
              new AccountExternalId(id, new AccountExternalId.Key(
                  AccountExternalId.SCHEME_USERNAME, username));
          if (!Strings.isNullOrEmpty(httpPassword)) {
            extUser.setPassword(httpPassword);
          }
          db.accountExternalIds().insert(Collections.singleton(extUser));

          if (email != null) {
            AccountExternalId extMailto =
                new AccountExternalId(id, new AccountExternalId.Key(
                    AccountExternalId.SCHEME_MAILTO, email));
            extMailto.setEmailAddress(email);
            db.accountExternalIds().insert(Collections.singleton(extMailto));
          }

          Account a = new Account(id, TimeUtil.nowTs());
          a.setFullName(name);
          a.setPreferredEmail(email);
          db.accounts().insert(Collections.singleton(a));

          AccountGroupName adminGroup = db.accountGroupNames().get(
              new AccountGroup.NameKey("Administrators"));
          AccountGroupMember m =
              new AccountGroupMember(new AccountGroupMember.Key(id,
                  adminGroup.getId()));
          db.accountGroupMembers().insert(Collections.singleton(m));

          if (sshKey != null) {
            VersionedAuthorizedKeysOnInit authorizedKeys =
                authorizedKeysFactory.create(id).load();
            authorizedKeys.addKey(sshKey.getSshPublicKey());
            authorizedKeys.save("Added SSH key for initial admin user\n");
          }
        }
      }
    }
  }

  private String readEmail(AccountSshKey sshKey) {
    String defaultEmail = "admin@example.com";
    if (sshKey != null && sshKey.getComment() != null) {
     String c = sshKey.getComment().trim();
     if (EmailValidator.getInstance().isValid(c)) {
       defaultEmail = c;
     }
    }
    return readEmail(defaultEmail);
  }

  private String readEmail(String defaultEmail) {
    String email = ui.readString(defaultEmail, "email");
    if (email != null && !EmailValidator.getInstance().isValid(email)) {
      ui.message("error: invalid email address\n");
      return readEmail(defaultEmail);
    }
    return email;
  }

  private AccountSshKey readSshKey(Account.Id id) throws IOException {
    String defaultPublicSshKeyFile = "";
    Path defaultPublicSshKeyPath =
        Paths.get(System.getProperty("user.home"), ".ssh", "id_rsa.pub");
    if (Files.exists(defaultPublicSshKeyPath)) {
      defaultPublicSshKeyFile = defaultPublicSshKeyPath.toString();
    }
    String publicSshKeyFile =
        ui.readString(defaultPublicSshKeyFile, "public SSH key file");
    return !Strings.isNullOrEmpty(publicSshKeyFile)
        ? createSshKey(id, publicSshKeyFile) : null;
  }

  private AccountSshKey createSshKey(Account.Id id, String keyFile)
      throws IOException {
    Path p = Paths.get(keyFile);
    if (!Files.exists(p)) {
      throw new IOException(String.format(
          "Cannot add public SSH key: %s is not a file", keyFile));
    }
    String content = new String(Files.readAllBytes(p), UTF_8);
    return new AccountSshKey(new AccountSshKey.Id(id, 1), content);
  }
}