/*
 * Copyright © 2024 Orange, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */
package org.opendaylight.transportpce.pce.constraints;

import java.util.BitSet;
import java.util.Map;
import java.util.concurrent.ExecutionException;
import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
import org.opendaylight.transportpce.common.fixedflex.GridConstant;
import org.opendaylight.transportpce.common.fixedflex.GridUtils;
import org.opendaylight.transportpce.common.network.NetworkTransactionService;
import org.opendaylight.yang.gen.v1.http.org.openroadm.common.optical.channel.types.rev230526.FrequencyTHz;
import org.opendaylight.yang.gen.v1.http.org.openroadm.controller.customization.rev230526.controller.parameters.SpectrumFilling;
import org.opendaylight.yang.gen.v1.http.org.openroadm.controller.customization.rev230526.controller.parameters.spectrum.filling.SpectrumFillingRules;
import org.opendaylight.yang.gen.v1.http.org.openroadm.controller.customization.rev230526.controller.parameters.spectrum.filling.SpectrumFillingRulesKey;
import org.opendaylight.yang.gen.v1.http.org.openroadm.service.rev230526.ControllerBehaviourSettings;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/*
 * Class to handle Operator Constraints associated with Specific Engineering rules
 * as they are defined in the controller-behaviour-settings container of the service
 * Data-Store.
 *
 */

public class OperatorConstraints {

    /* Logging. */
    private static final Logger LOG = LoggerFactory.getLogger(OperatorConstraints.class);
    private NetworkTransactionService networkTransaction;

    public OperatorConstraints(NetworkTransactionService networkTransaction) {

        this.networkTransaction = networkTransaction;

    }

    public BitSet getBitMapConstraint(String customerName) {
        BitSet referenceBitSet = new BitSet(GridConstant.EFFECTIVE_BITS);
        referenceBitSet.set(0, GridConstant.EFFECTIVE_BITS, true);
        InstanceIdentifier<SpectrumFilling> sfIID =
            InstanceIdentifier
                .builder(ControllerBehaviourSettings.class)
                .child(SpectrumFilling.class)
                .build();

        try {
            if (networkTransaction.read(LogicalDatastoreType.CONFIGURATION, sfIID).get().isPresent()) {
                SpectrumFilling spectrumConstraint = networkTransaction
                    .read(LogicalDatastoreType.CONFIGURATION, sfIID).get().orElseThrow();
                if (spectrumConstraint.getSpectrumFillingRules().isEmpty()) {
                    return referenceBitSet;
                }
                for (Map.Entry<SpectrumFillingRulesKey, SpectrumFillingRules> rule:
                        spectrumConstraint.getSpectrumFillingRules().entrySet()) {
                    FrequencyTHz startFreq = rule.getValue().getSpectrumRangeOfAppliance().getStartEdgeFrequency();
                    FrequencyTHz stopFreq = rule.getValue().getSpectrumRangeOfAppliance().getStopEdgeFrequency();
                    if (customerName != null
                            && rule.getValue().getSpectrumRangeOfAppliance().getNonAuthorizedCustomer() != null
                            && rule.getValue().getSpectrumRangeOfAppliance().getNonAuthorizedCustomer()
                                .contains(customerName)) {
                        //Customer shall not be put in this spectrum portion
                        referenceBitSet.set(
                            GridUtils.getIndexFromFrequency(startFreq.getValue()),
                            GridUtils.getIndexFromFrequency(stopFreq.getValue()), false);
                        LOG.info("Specific Spectrum filling Rules have been defined for customer {}, exluding it from "
                            + "the spectrum range {} - {} ", customerName, startFreq.toString(), stopFreq.toString());
                    } else if (customerName != null
                            && rule.getValue().getSpectrumRangeOfAppliance().getDedicatedCustomer() != null
                            && rule.getValue().getSpectrumRangeOfAppliance()
                                .getDedicatedCustomer().contains(customerName)) {
                        // Spectrum portion is dedicated to customers including this one
                        referenceBitSet.set(
                            GridUtils.getIndexFromFrequency(startFreq.getValue()),
                            GridUtils.getIndexFromFrequency(stopFreq.getValue()), true);
                        LOG.info("Specific Spectrum filling Rules have been defined for customer {}, to dedicate "
                            + "spectrum range {} - {} to it ", customerName, startFreq.toString(), stopFreq.toString());
                    } else if (rule.getValue().getSpectrumRangeOfAppliance().getDedicatedCustomer() != null
                            && !rule.getValue().getSpectrumRangeOfAppliance().getDedicatedCustomer().isEmpty()) {
                        // Spectrum portion is dedicated to some customers that do not include this one
                        referenceBitSet.set(
                            GridUtils.getIndexFromFrequency(startFreq.getValue()),
                            GridUtils.getIndexFromFrequency(stopFreq.getValue()), false);
                        LOG.info("Specific Spectrum filling Rules have been defined for other customers, preventing"
                            + " the customer to use spectrum range {}--{}", startFreq.toString(), stopFreq.toString());
                    }
                }
                return referenceBitSet;
            }
        } catch (InterruptedException | ExecutionException e1) {
            LOG.error("Exception caught handling Spectrum filling Rules {} ", e1.getCause().toString());
        }
        LOG.info("Did not succeed finding any Specific Spectrum filling Rules defined in Configuration Datastore");
        return referenceBitSet;
    }
}