// 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.account;

import com.google.gerrit.common.data.AccountSecurity;
import com.google.gerrit.common.errors.ContactInformationStoreException;
import com.google.gerrit.common.errors.InvalidSshKeyException;
import com.google.gerrit.common.errors.NameAlreadyUsedException;
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.AccountAgreement;
import com.google.gerrit.reviewdb.AccountExternalId;
import com.google.gerrit.reviewdb.AccountGroup;
import com.google.gerrit.reviewdb.AccountSshKey;
import com.google.gerrit.reviewdb.ContactInformation;
import com.google.gerrit.reviewdb.ContributorAgreement;
import com.google.gerrit.reviewdb.ReviewDb;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.IdentifiedUser;
import com.google.gerrit.server.account.AccountByEmailCache;
import com.google.gerrit.server.account.AccountCache;
import com.google.gerrit.server.account.AccountException;
import com.google.gerrit.server.account.AccountManager;
import com.google.gerrit.server.account.AuthRequest;
import com.google.gerrit.server.account.ChangeUserName;
import com.google.gerrit.server.account.ClearPassword;
import com.google.gerrit.server.account.GeneratePassword;
import com.google.gerrit.server.account.Realm;
import com.google.gerrit.server.config.AuthConfig;
import com.google.gerrit.server.contact.ContactStore;
import com.google.gerrit.server.mail.EmailException;
import com.google.gerrit.server.mail.RegisterNewEmailSender;
import com.google.gerrit.server.ssh.SshKeyCache;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwtjsonrpc.client.VoidResult;
import com.google.gwtjsonrpc.server.ValidToken;
import com.google.gwtjsonrpc.server.XsrfException;
import com.google.gwtorm.client.OrmException;
import com.google.inject.Inject;
import com.google.inject.Provider;

import org.eclipse.jgit.util.Base64;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.UnsupportedEncodingException;
import java.util.Collections;
import java.util.List;
import java.util.Set;

class AccountSecurityImpl extends BaseServiceImplementation implements
    AccountSecurity {
  private final Logger log = LoggerFactory.getLogger(getClass());
  private final ContactStore contactStore;
  private final AuthConfig authConfig;
  private final Realm realm;
  private final Provider<IdentifiedUser> user;
  private final RegisterNewEmailSender.Factory registerNewEmailFactory;
  private final SshKeyCache sshKeyCache;
  private final AccountByEmailCache byEmailCache;
  private final AccountCache accountCache;
  private final AccountManager accountManager;
  private final boolean useContactInfo;

  private final ClearPassword.Factory clearPasswordFactory;
  private final GeneratePassword.Factory generatePasswordFactory;
  private final ChangeUserName.CurrentUser changeUserNameFactory;
  private final DeleteExternalIds.Factory deleteExternalIdsFactory;
  private final ExternalIdDetailFactory.Factory externalIdDetailFactory;
  private final MyGroupsFactory.Factory myGroupsFactory;

  @Inject
  AccountSecurityImpl(final Provider<ReviewDb> schema,
      final Provider<CurrentUser> currentUser, final ContactStore cs,
      final AuthConfig ac, final Realm r, final Provider<IdentifiedUser> u,
      final RegisterNewEmailSender.Factory esf, final SshKeyCache skc,
      final AccountByEmailCache abec, final AccountCache uac,
      final AccountManager am,
      final ClearPassword.Factory clearPasswordFactory,
      final GeneratePassword.Factory generatePasswordFactory,
      final ChangeUserName.CurrentUser changeUserNameFactory,
      final DeleteExternalIds.Factory deleteExternalIdsFactory,
      final ExternalIdDetailFactory.Factory externalIdDetailFactory,
      final MyGroupsFactory.Factory myGroupsFactory) {
    super(schema, currentUser);
    contactStore = cs;
    authConfig = ac;
    realm = r;
    user = u;
    registerNewEmailFactory = esf;
    sshKeyCache = skc;
    byEmailCache = abec;
    accountCache = uac;
    accountManager = am;

    useContactInfo = contactStore != null && contactStore.isEnabled();

    this.clearPasswordFactory = clearPasswordFactory;
    this.generatePasswordFactory = generatePasswordFactory;
    this.changeUserNameFactory = changeUserNameFactory;
    this.deleteExternalIdsFactory = deleteExternalIdsFactory;
    this.externalIdDetailFactory = externalIdDetailFactory;
    this.myGroupsFactory = myGroupsFactory;
  }

  public void mySshKeys(final AsyncCallback<List<AccountSshKey>> callback) {
    run(callback, new Action<List<AccountSshKey>>() {
      public List<AccountSshKey> run(ReviewDb db) throws OrmException {
        IdentifiedUser u = user.get();
        return db.accountSshKeys().byAccount(u.getAccountId()).toList();
      }
    });
  }

  public void addSshKey(final String keyText,
      final AsyncCallback<AccountSshKey> callback) {
    run(callback, new Action<AccountSshKey>() {
      public AccountSshKey run(final ReviewDb db) throws OrmException, Failure {
        int max = 0;
        final Account.Id me = user.get().getAccountId();
        for (final AccountSshKey k : db.accountSshKeys().byAccount(me)) {
          max = Math.max(max, k.getKey().get());
        }

        final AccountSshKey key;
        try {
          key = sshKeyCache.create(new AccountSshKey.Id(me, max + 1), keyText);
        } catch (InvalidSshKeyException e) {
          throw new Failure(e);
        }
        db.accountSshKeys().insert(Collections.singleton(key));
        uncacheSshKeys();
        return key;
      }
    });
  }

  public void deleteSshKeys(final Set<AccountSshKey.Id> ids,
      final AsyncCallback<VoidResult> callback) {
    run(callback, new Action<VoidResult>() {
      public VoidResult run(final ReviewDb db) throws OrmException, Failure {
        final Account.Id me = user.get().getAccountId();
        for (final AccountSshKey.Id keyId : ids) {
          if (!me.equals(keyId.getParentKey()))
            throw new Failure(new NoSuchEntityException());
        }

        db.accountSshKeys().deleteKeys(ids);
        uncacheSshKeys();

        return VoidResult.INSTANCE;
      }
    });
  }

  private void uncacheSshKeys() {
    sshKeyCache.evict(user.get().getUserName());
  }

  @Override
  public void changeUserName(final String newName,
      final AsyncCallback<VoidResult> callback) {
    if (realm.allowsEdit(Account.FieldName.USER_NAME)) {
      Handler.wrap(changeUserNameFactory.create(newName)).to(callback);
    } else {
      callback.onFailure(new NameAlreadyUsedException());
    }
  }

  @Override
  public void generatePassword(AccountExternalId.Key key,
      AsyncCallback<AccountExternalId> callback) {
    Handler.wrap(generatePasswordFactory.create(key)).to(callback);
  }

  @Override
  public void clearPassword(AccountExternalId.Key key,
      AsyncCallback<AccountExternalId> callback) {
    Handler.wrap(clearPasswordFactory.create(key)).to(callback);
  }

  public void myExternalIds(AsyncCallback<List<AccountExternalId>> callback) {
    externalIdDetailFactory.create().to(callback);
  }

  @Override
  public void myGroups(final AsyncCallback<List<AccountGroup>> callback) {
    myGroupsFactory.create().to(callback);
  }

  public void deleteExternalIds(final Set<AccountExternalId.Key> keys,
      final AsyncCallback<Set<AccountExternalId.Key>> callback) {
    deleteExternalIdsFactory.create(keys).to(callback);
  }

  public void updateContact(final String name, final String emailAddr,
      final ContactInformation info, final AsyncCallback<Account> callback) {
    run(callback, new Action<Account>() {
      public Account run(ReviewDb db) throws OrmException, Failure {
        final Account me = db.accounts().get(user.get().getAccountId());
        final String oldEmail = me.getPreferredEmail();
        if (realm.allowsEdit(Account.FieldName.FULL_NAME)) {
          me.setFullName(name != null && !name.isEmpty() ? name : null);
        }
        me.setPreferredEmail(emailAddr);
        if (useContactInfo) {
          if (ContactInformation.hasAddress(info)
              || (me.isContactFiled() && ContactInformation.hasData(info))) {
            me.setContactFiled();
          }
          if (ContactInformation.hasData(info)) {
            try {
              contactStore.store(me, info);
            } catch (ContactInformationStoreException e) {
              throw new Failure(e);
            }
          }
        }
        db.accounts().update(Collections.singleton(me));
        if (!eq(oldEmail, me.getPreferredEmail())) {
          byEmailCache.evict(oldEmail);
          byEmailCache.evict(me.getPreferredEmail());
        }
        accountCache.evict(me.getId());
        return me;
      }
    });
  }

  private static boolean eq(final String a, final String b) {
    if (a == null && b == null) {
      return true;
    }
    return a != null && a.equals(b);
  }

  public void enterAgreement(final ContributorAgreement.Id id,
      final AsyncCallback<VoidResult> callback) {
    run(callback, new Action<VoidResult>() {
      public VoidResult run(final ReviewDb db) throws OrmException, Failure {
        final ContributorAgreement cla = db.contributorAgreements().get(id);
        if (cla == null || !cla.isActive()) {
          throw new Failure(new NoSuchEntityException());
        }

        final AccountAgreement a =
            new AccountAgreement(new AccountAgreement.Key(user.get()
                .getAccountId(), id));
        if (cla.isAutoVerify()) {
          a.review(AccountAgreement.Status.VERIFIED, null);
        }
        db.accountAgreements().insert(Collections.singleton(a));
        return VoidResult.INSTANCE;
      }
    });
  }

  public void registerEmail(final String address,
      final AsyncCallback<VoidResult> cb) {
    try {
      final RegisterNewEmailSender sender;
      sender = registerNewEmailFactory.create(address);
      sender.send();
      cb.onSuccess(VoidResult.INSTANCE);
    } catch (EmailException e) {
      log.error("Cannot send email verification message to " + address, e);
      cb.onFailure(e);
    } catch (RuntimeException e) {
      log.error("Cannot send email verification message to " + address, e);
      cb.onFailure(e);
    }
  }

  public void validateEmail(final String token,
      final AsyncCallback<VoidResult> callback) {
    try {
      final ValidToken t =
          authConfig.getEmailRegistrationToken().checkToken(token, null);
      if (t == null || t.getData() == null || "".equals(t.getData())) {
        callback.onFailure(new IllegalStateException("Invalid token"));
        return;
      }
      final String newEmail = new String(Base64.decode(t.getData()), "UTF-8");
      if (!newEmail.contains("@")) {
        callback.onFailure(new IllegalStateException("Invalid token"));
        return;
      }
      accountManager.link(user.get().getAccountId(), AuthRequest
          .forEmail(newEmail));
      callback.onSuccess(VoidResult.INSTANCE);
    } catch (XsrfException e) {
      callback.onFailure(e);
    } catch (UnsupportedEncodingException e) {
      callback.onFailure(e);
    } catch (AccountException e) {
      callback.onFailure(e);
    }
  }
}