/*
 * Copyright 2021-present Open Networking Foundation
 *
 * 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.onosproject.net.behaviour.upf;


import static com.google.common.base.Preconditions.checkNotNull;

/**
 * A structure for compactly passing PDR counter values for a given counter ID.
 * Contains four counts: Ingress Packets, Ingress Bytes, Egress Packets, Egress Bytes
 */
public final class PdrStats {
    private final int cellId;
    private final long ingressPkts;
    private final long ingressBytes;
    private final long egressPkts;
    private final long egressBytes;

    private PdrStats(int cellId, long ingressPkts, long ingressBytes,
                     long egressPkts, long egressBytes) {
        this.cellId = cellId;
        this.ingressPkts = ingressPkts;
        this.ingressBytes = ingressBytes;
        this.egressPkts = egressPkts;
        this.egressBytes = egressBytes;
    }

    public static Builder builder() {
        return new Builder();
    }

    @Override
    public String toString() {
        return String.format("PDR-Stats:{ CellID: %d, Ingress:(%dpkts,%dbytes), Egress:(%dpkts,%dbytes) }",
                cellId, ingressPkts, ingressBytes, egressPkts, egressBytes);
    }

    /**
     * Get the cell ID (index) of the dataplane PDR counter that produced this set of stats.
     *
     * @return counter cell ID
     */
    public int getCellId() {
        return cellId;
    }

    /**
     * Get the number of packets that hit this counter in the dataplane ingress pipeline.
     *
     * @return ingress packet count
     */
    public long getIngressPkts() {
        return ingressPkts;
    }

    /**
     * Get the number of packets that hit this counter in the dataplane egress pipeline.
     *
     * @return egress packet count
     */
    public long getEgressPkts() {
        return egressPkts;
    }

    /**
     * Get the number of packet bytes that hit this counter in the dataplane ingress pipeline.
     *
     * @return ingress byte count
     */
    public long getIngressBytes() {
        return ingressBytes;
    }

    /**
     * Get the number of packet bytes that hit this counter in the dataplane egress pipeline.
     *
     * @return egress byte count
     */
    public long getEgressBytes() {
        return egressBytes;
    }

    public static class Builder {
        private Integer cellId;
        private long ingressPkts;
        private long ingressBytes;
        private long egressPkts;
        private long egressBytes;

        public Builder() {
            this.ingressPkts = 0;
            this.ingressBytes = 0;
            this.egressPkts = 0;
            this.egressBytes = 0;
        }

        /**
         * Set the Cell ID (index) of the datalane PDR counter that produced this set of stats.
         *
         * @param cellId the counter cell ID
         * @return This builder
         */
        public Builder withCellId(int cellId) {
            this.cellId = cellId;
            return this;
        }

        /**
         * Set the number of packets and bytes that hit the PDR counter in the dataplane ingress pipeline.
         *
         * @param ingressPkts  ingress packet count
         * @param ingressBytes egress packet count
         * @return This builder
         */
        public Builder setIngress(long ingressPkts, long ingressBytes) {
            this.ingressPkts = ingressPkts;
            this.ingressBytes = ingressBytes;
            return this;
        }

        /**
         * Set the number of packets and bytes that hit the PDR counter in the dataplane egress pipeline.
         *
         * @param egressPkts  egress packet count
         * @param egressBytes egress byte count
         * @return This builder
         */
        public Builder setEgress(long egressPkts, long egressBytes) {
            this.egressPkts = egressPkts;
            this.egressBytes = egressBytes;
            return this;
        }

        public PdrStats build() {
            checkNotNull(cellId, "CellID must be provided");
            return new PdrStats(cellId, ingressPkts, ingressBytes, egressPkts, egressBytes);
        }
    }
}