/*
 * Copyright (C) 2019 Bell Canada.
 *
 * 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 org.onap.ccsdk.cds.blueprintsprocessor.functions.config.snapshots.db

import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.withContext
import org.apache.logging.log4j.util.Strings
import org.onap.ccsdk.cds.blueprintsprocessor.functions.config.snapshots.db.ResourceConfigSnapshot.Status.RUNNING
import org.onap.ccsdk.cds.controllerblueprints.core.BluePrintException
import org.slf4j.LoggerFactory
import org.springframework.dao.DataIntegrityViolationException
import org.springframework.stereotype.Service
import java.util.*
import kotlin.NoSuchElementException

/**
 * ResourceConfigSnapshot managing service.
 *
 * @author Serge Simard
 * @version 1.0
 */
@Service
class ResourceConfigSnapshotService(private val repository: ResourceConfigSnapshotRepository) {

    private val log = LoggerFactory.getLogger(ResourceConfigSnapshotService::class.toString())

    suspend fun findByResourceIdAndResourceTypeAndStatus(resourceId: String, resourceType: String,
                                                         status : ResourceConfigSnapshot.Status = RUNNING): String =
            withContext(Dispatchers.IO) {
                repository.findByResourceIdAndResourceTypeAndStatus(resourceId, resourceType, status)
                        ?.config_snapshot ?: Strings.EMPTY
            }

    suspend fun write(snapshot: String, resId: String, resType: String,
                      status: ResourceConfigSnapshot.Status = RUNNING) : ResourceConfigSnapshot =
            withContext(Dispatchers.IO) {

                val resourceConfigSnapshotEntry = ResourceConfigSnapshot()
                resourceConfigSnapshotEntry.id = UUID.randomUUID().toString()
                resourceConfigSnapshotEntry.resourceId = resId
                resourceConfigSnapshotEntry.resourceType = resType
                resourceConfigSnapshotEntry.status = status
                resourceConfigSnapshotEntry.config_snapshot = snapshot

                // Overwrite configuration snapshot entry of resId/resType
                if (resId.isNotEmpty() && resType.isNotEmpty()) {
                    repository.findByResourceIdAndResourceTypeAndStatus(resId, resType, status)?.
                        let {
                            log.info("Overwriting configuration snapshot entry for resourceId=($resId), " +
                                "resourceType=($resType), status=($status)")
                            repository.deleteByResourceIdAndResourceTypeAndStatus(resId, resType, status)
                        }
                }
                var storedSnapshot: ResourceConfigSnapshot
                try {
                    storedSnapshot = repository.saveAndFlush(resourceConfigSnapshotEntry)
                    log.info("Stored configuration snapshot for resourceId=($resId), " +
                            "resourceType=($resType), status=($status), " +
                            "dated=(${storedSnapshot.createdDate})")
                } catch (ex: DataIntegrityViolationException) {
                    throw BluePrintException("Failed to store configuration snapshot entry.", ex)
                }
                storedSnapshot
            }
}