/*
 * Copyright 2010-2013 Ning, Inc.
 * Copyright 2014-2016 Groupon, Inc
 * Copyright 2014-2016 The Billing Project, LLC
 *
 * The Billing Project licenses this file to you 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 org.killbill.billing.account.dao;

import java.util.Iterator;
import java.util.List;
import java.util.UUID;

import org.killbill.billing.BillingExceptionBase;
import org.killbill.billing.ErrorCode;
import org.killbill.billing.account.api.Account;
import org.killbill.billing.account.api.AccountApiException;
import org.killbill.billing.account.api.user.DefaultAccountChangeEvent;
import org.killbill.billing.account.api.user.DefaultAccountCreationEvent;
import org.killbill.billing.account.api.user.DefaultAccountCreationEvent.DefaultAccountData;
import org.killbill.billing.callcontext.InternalCallContext;
import org.killbill.billing.callcontext.InternalTenantContext;
import org.killbill.billing.entity.EntityPersistenceException;
import org.killbill.billing.events.AccountChangeInternalEvent;
import org.killbill.billing.events.AccountCreationInternalEvent;
import org.killbill.billing.util.audit.ChangeType;
import org.killbill.billing.util.cache.CacheControllerDispatcher;
import org.killbill.billing.util.callcontext.InternalCallContextFactory;
import org.killbill.billing.util.dao.NonEntityDao;
import org.killbill.billing.util.entity.DefaultPagination;
import org.killbill.billing.util.entity.Pagination;
import org.killbill.billing.util.entity.dao.DefaultPaginationSqlDaoHelper.Ordering;
import org.killbill.billing.util.entity.dao.DefaultPaginationSqlDaoHelper.PaginationIteratorBuilder;
import org.killbill.billing.util.entity.dao.EntityDaoBase;
import org.killbill.billing.util.entity.dao.EntitySqlDaoTransactionWrapper;
import org.killbill.billing.util.entity.dao.EntitySqlDaoTransactionalJdbiWrapper;
import org.killbill.billing.util.entity.dao.EntitySqlDaoWrapperFactory;
import org.killbill.bus.api.PersistentBus;
import org.killbill.bus.api.PersistentBus.EventBusException;
import org.killbill.clock.Clock;
import org.skife.jdbi.v2.IDBI;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.ImmutableList;
import com.google.inject.Inject;

public class DefaultAccountDao extends EntityDaoBase<AccountModelDao, Account, AccountApiException> implements AccountDao {

    private static final Logger log = LoggerFactory.getLogger(DefaultAccountDao.class);

    private final PersistentBus eventBus;
    private final InternalCallContextFactory internalCallContextFactory;
    private final Clock clock;

    @Inject
    public DefaultAccountDao(final IDBI dbi, final PersistentBus eventBus, final Clock clock, final CacheControllerDispatcher cacheControllerDispatcher,
                             final InternalCallContextFactory internalCallContextFactory, final NonEntityDao nonEntityDao) {
        super(new EntitySqlDaoTransactionalJdbiWrapper(dbi, clock, cacheControllerDispatcher, nonEntityDao, internalCallContextFactory), AccountSqlDao.class);
        this.eventBus = eventBus;
        this.internalCallContextFactory = internalCallContextFactory;
        this.clock = clock;
    }

    @Override
    protected AccountApiException generateAlreadyExistsException(final AccountModelDao account, final InternalCallContext context) {
        return new AccountApiException(ErrorCode.ACCOUNT_ALREADY_EXISTS, account.getExternalKey());
    }

    @Override
    protected void postBusEventFromTransaction(final AccountModelDao account, final AccountModelDao savedAccount, final ChangeType changeType,
                                               final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory, final InternalCallContext context) throws BillingExceptionBase {
        // This is only called for the create call (see update below)
        switch (changeType) {
            case INSERT:
                break;
            default:
                return;
        }

        final Long recordId = entitySqlDaoWrapperFactory.become(AccountSqlDao.class).getRecordId(savedAccount.getId().toString(), context);
        // We need to re-hydrate the callcontext with the account record id
        final InternalCallContext rehydratedContext = internalCallContextFactory.createInternalCallContext(recordId, context);
        final AccountCreationInternalEvent creationEvent = new DefaultAccountCreationEvent(new DefaultAccountData(savedAccount), savedAccount.getId(),
                                                                                           rehydratedContext.getAccountRecordId(), rehydratedContext.getTenantRecordId(), rehydratedContext.getUserToken());
        try {
            eventBus.postFromTransaction(creationEvent, entitySqlDaoWrapperFactory.getHandle().getConnection());
        } catch (final EventBusException e) {
            log.warn("Failed to post account creation event for accountId='{}'", savedAccount.getId(), e);
        }
    }

    @Override
    public AccountModelDao getAccountByKey(final String key, final InternalTenantContext context) {
        return transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<AccountModelDao>() {
            @Override
            public AccountModelDao inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                return entitySqlDaoWrapperFactory.become(AccountSqlDao.class).getAccountByKey(key, context);
            }
        });
    }

    @Override
    public Pagination<AccountModelDao> searchAccounts(final String searchKey, final Long offset, final Long limit, final InternalTenantContext context) {
        final boolean userIsFeelingLucky = limit == 1 && offset == -1;
        if (userIsFeelingLucky) {
            // The use-case we can optimize is when the user is looking for an exact match (e.g. he knows the full email). In that case, we can speed up the queries
            // by doing exact searches only.
            final AccountModelDao accountModelDao = transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<AccountModelDao>() {
                @Override
                public AccountModelDao inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                    return entitySqlDaoWrapperFactory.become(AccountSqlDao.class).luckySearch(searchKey, context);
                }
            });
            return new DefaultPagination<AccountModelDao>(0L,
                                                          1L,
                                                          accountModelDao == null ? 0L : 1L,
                                                          null, // We don't compute stats for speed in that case
                                                          accountModelDao == null ? ImmutableList.<AccountModelDao>of().iterator() : ImmutableList.<AccountModelDao>of(accountModelDao).iterator());
        }

        // Otherwise, we pretty much need to do a full table scan (leading % in the like clause).
        // Note: forcing MySQL to search indexes (like luckySearch above) doesn't always seem to help on large tables, especially with large offsets
        return paginationHelper.getPagination(AccountSqlDao.class,
                                              new PaginationIteratorBuilder<AccountModelDao, Account, AccountSqlDao>() {
                                                  @Override
                                                  public Long getCount(final AccountSqlDao accountSqlDao, final InternalTenantContext context) {
                                                      return accountSqlDao.getSearchCount(searchKey, String.format("%%%s%%", searchKey), context);
                                                  }

                                                  @Override
                                                  public Iterator<AccountModelDao> build(final AccountSqlDao accountSqlDao, final Long offset, final Long limit, final Ordering ordering, final InternalTenantContext context) {
                                                      return accountSqlDao.search(searchKey, String.format("%%%s%%", searchKey), offset, limit, ordering.toString(), context);
                                                  }
                                              },
                                              offset,
                                              limit,
                                              context);
    }

    @Override
    public UUID getIdFromKey(final String externalKey, final InternalTenantContext context) throws AccountApiException {
        if (externalKey == null) {
            throw new AccountApiException(ErrorCode.ACCOUNT_CANNOT_MAP_NULL_KEY, "");
        }

        return transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<UUID>() {
            @Override
            public UUID inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                return entitySqlDaoWrapperFactory.become(AccountSqlDao.class).getIdFromKey(externalKey, context);
            }
        });
    }

    @Override
    public void update(final AccountModelDao specifiedAccount, final InternalCallContext context) throws AccountApiException {
        transactionalSqlDao.execute(AccountApiException.class, new EntitySqlDaoTransactionWrapper<Void>() {
            @Override
            public Void inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws EventBusException, AccountApiException {
                final AccountSqlDao transactional = entitySqlDaoWrapperFactory.become(AccountSqlDao.class);

                final UUID accountId = specifiedAccount.getId();
                final AccountModelDao currentAccount = transactional.getById(accountId.toString(), context);
                if (currentAccount == null) {
                    throw new AccountApiException(ErrorCode.ACCOUNT_DOES_NOT_EXIST_FOR_ID, accountId);
                }

                transactional.update(specifiedAccount, context);

                final AccountChangeInternalEvent changeEvent = new DefaultAccountChangeEvent(accountId,
                                                                                             currentAccount,
                                                                                             specifiedAccount,
                                                                                             context.getAccountRecordId(),
                                                                                             context.getTenantRecordId(),
                                                                                             context.getUserToken(),
                                                                                             clock.getUTCNow());
                try {
                    eventBus.postFromTransaction(changeEvent, entitySqlDaoWrapperFactory.getHandle().getConnection());
                } catch (final EventBusException e) {
                    log.warn("Failed to post account change event for accountId='{}'", accountId, e);
                }

                return null;
            }
        });
    }

    @Override
    public void updatePaymentMethod(final UUID accountId, final UUID paymentMethodId, final InternalCallContext context) throws AccountApiException {
        transactionalSqlDao.execute(AccountApiException.class, new EntitySqlDaoTransactionWrapper<Void>() {
            @Override
            public Void inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws EntityPersistenceException, EventBusException {
                final AccountSqlDao transactional = entitySqlDaoWrapperFactory.become(AccountSqlDao.class);

                final AccountModelDao currentAccount = transactional.getById(accountId.toString(), context);
                if (currentAccount == null) {
                    throw new EntityPersistenceException(ErrorCode.ACCOUNT_DOES_NOT_EXIST_FOR_ID, accountId);
                }

                // Check if an update is really needed. If not, bail early to avoid sending an extra event on the bus
                if ((currentAccount.getPaymentMethodId() == null && paymentMethodId == null) ||
                    (currentAccount.getPaymentMethodId() != null && currentAccount.getPaymentMethodId().equals(paymentMethodId))) {
                    return null;
                }

                final String thePaymentMethodId = paymentMethodId != null ? paymentMethodId.toString() : null;
                transactional.updatePaymentMethod(accountId.toString(), thePaymentMethodId, context);

                final AccountModelDao account = transactional.getById(accountId.toString(), context);
                final AccountChangeInternalEvent changeEvent = new DefaultAccountChangeEvent(accountId, currentAccount, account,
                                                                                             context.getAccountRecordId(),
                                                                                             context.getTenantRecordId(),
                                                                                             context.getUserToken(),
                                                                                             clock.getUTCNow());

                try {
                    eventBus.postFromTransaction(changeEvent, entitySqlDaoWrapperFactory.getHandle().getConnection());
                } catch (final EventBusException e) {
                    log.warn("Failed to post account change event for accountId='{}'", accountId, e);
                }
                return null;
            }
        });
    }

    @Override
    public void addEmail(final AccountEmailModelDao email, final InternalCallContext context) throws AccountApiException {
        transactionalSqlDao.execute(AccountApiException.class, new EntitySqlDaoTransactionWrapper<Void>() {
            @Override
            public Void inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                final AccountEmailSqlDao transactional = entitySqlDaoWrapperFactory.become(AccountEmailSqlDao.class);

                if (transactional.getById(email.getId().toString(), context) != null) {
                    throw new AccountApiException(ErrorCode.ACCOUNT_EMAIL_ALREADY_EXISTS, email.getId());
                }

                transactional.create(email, context);
                return null;
            }
        });
    }

    @Override
    public void removeEmail(final AccountEmailModelDao email, final InternalCallContext context) {
        transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<Void>() {
            @Override
            public Void inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                entitySqlDaoWrapperFactory.become(AccountEmailSqlDao.class).markEmailAsDeleted(email, context);
                return null;
            }
        });
    }

    @Override
    public List<AccountEmailModelDao> getEmailsByAccountId(final UUID accountId, final InternalTenantContext context) {
        return transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<List<AccountEmailModelDao>>() {
            @Override
            public List<AccountEmailModelDao> inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                return entitySqlDaoWrapperFactory.become(AccountEmailSqlDao.class).getEmailByAccountId(accountId, context);
            }
        });
    }

    @Override
    public Integer getAccountBCD(final UUID accountId, final InternalTenantContext context) {
        return transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<Integer>() {
            @Override
            public Integer inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                return entitySqlDaoWrapperFactory.become(AccountSqlDao.class).getBCD(accountId.toString(), context);
            }
        });
    }

    @Override
    public List<AccountModelDao> getAccountsByParentId(final UUID parentAccountId, final InternalTenantContext context) {
        return transactionalSqlDao.execute(new EntitySqlDaoTransactionWrapper<List<AccountModelDao>>() {
            @Override
            public List<AccountModelDao> inTransaction(final EntitySqlDaoWrapperFactory entitySqlDaoWrapperFactory) throws Exception {
                return entitySqlDaoWrapperFactory.become(AccountSqlDao.class).getAccountsByParentId(parentAccountId, context);
            }
        });
    }
}
