/*
 * ============LICENSE_START=======================================================
 * dcaegen2-collectors-veshv
 * ================================================================================
 * Copyright (C) 2018-2019 NOKIA
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */
package org.onap.dcae.collectors.veshv.impl

import arrow.core.Option
import arrow.core.toOption
import org.onap.dcae.collectors.veshv.config.api.model.Route
import org.onap.dcae.collectors.veshv.config.api.model.Routing
import org.onap.dcae.collectors.veshv.model.ClientContext
import org.onap.dcae.collectors.veshv.impl.adapters.ClientContextLogging.debug
import org.onap.dcae.collectors.veshv.domain.RoutedMessage
import org.onap.dcae.collectors.veshv.domain.VesMessage
import org.onap.dcae.collectors.veshv.utils.arrow.doOnEmpty
import org.onap.dcae.collectors.veshv.utils.logging.Logger
import org.onap.dcaegen2.services.sdk.model.streams.dmaap.KafkaSink
import org.onap.ves.VesEventOuterClass.CommonEventHeader

class Router(private val routing: Routing, private val ctx: ClientContext) {

    constructor(kafkaSinks: Sequence<KafkaSink>, ctx: ClientContext) : this(
            Routing(
                    kafkaSinks.map { Route(it.name(), it.topicName()) }.toList()
            ),
            ctx)

    fun findDestination(message: VesMessage): Option<RoutedMessage> =
            routeFor(message.header)
                    .doOnEmpty { logger.debug(ctx) { "No route is defined for domain: ${message.header.domain}" } }
                    .map { it.routeMessage(message) }

    private fun Route.routeMessage(message: VesMessage) =
            RoutedMessage(targetTopic, partitioning(message.header), message)

    private fun routeFor(commonHeader: CommonEventHeader): Option<Route> =
            routing.routes.find { it.domain == commonHeader.domain }.toOption()

    companion object {
        private val logger = Logger(Routing::class)
    }
}