/*
 * Copyright (c) 2014 Piotr Gawlowicz
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 * Author: Piotr Gawlowicz <gawlowicz.p@gmail.com>
 *
 */

#ifndef LTE_FFR_ALGORITHM_H
#define LTE_FFR_ALGORITHM_H

#include "epc-x2-sap.h"
#include "ff-mac-sched-sap.h"
#include "lte-rrc-sap.h"

#include "ns3/object.h"

#include <map>

namespace ns3
{

class LteFfrSapUser;
class LteFfrSapProvider;

class LteFfrRrcSapUser;
class LteFfrRrcSapProvider;

/**
 * @brief The abstract base class of a Frequency Reuse algorithm
 *
 * Generally Frequency reuse algorithm tells the Scheduler which RB can be allocated
 * and which can not. FR policy depend on its implementation.
 *
 * The communication with the eNodeB MAC Scheduler instance is done through
 * the *LteFfrSap* interface. The frequency reuse algorithm instance corresponds to the
 * "provider" part of this interface, while the eNodeB MAC Scheduler instance takes the
 * role of the "user" part.
 *
 * The communication with the eNodeB RRC instance is done through the *LteFfrRrcSap*
 * interface. The frequency reuse algorithm instance corresponds to the
 * "provider" part of this interface, while the eNodeB RRC instance takes the
 * role of the "user" part.
 *
 */

class LteFfrAlgorithm : public Object
{
  public:
    LteFfrAlgorithm();
    ~LteFfrAlgorithm() override;

    /**
     * @brief Get the type ID.
     * @return the object TypeId
     */
    static TypeId GetTypeId();

    /**
     * @brief Set the "user" part of the LteFfrSap interface that
     *        this frequency reuse algorithm instance will interact with.
     * @param s a reference to the "user" part of the interface, typically a
     *          member of an Scheduler instance
     */
    virtual void SetLteFfrSapUser(LteFfrSapUser* s) = 0;

    /**
     * @brief Set the "user" part of the LteFfrRrcSap interface that
     *        this frequency reuse algorithm instance will interact with.
     * @param s a reference to the "user" part of the interface, typically a
     *          member of an LteEnbRrc instance
     */
    virtual void SetLteFfrRrcSapUser(LteFfrRrcSapUser* s) = 0;

    /**
     * @brief Export the "provider" part of the LteFfrSap interface.
     * @return the reference to the "provider" part of the interface, typically to
     *         be kept by an Scheduler instance
     */
    virtual LteFfrSapProvider* GetLteFfrSapProvider() = 0;

    /**
     * @brief Export the "provider" part of the LteFfrRrcSap interface.
     * @return the reference to the "provider" part of the interface, typically to
     *         be kept by an LteEnbRrc instance
     */
    virtual LteFfrRrcSapProvider* GetLteFfrRrcSapProvider() = 0;

    /**
     * @return the uplink bandwidth in RBs
     */
    uint16_t GetUlBandwidth() const;

    /**
     * @param bw the uplink bandwidth in RBs
     */
    void SetUlBandwidth(uint16_t bw);

    /**
     * @return the downlink bandwidth in RBs
     */
    uint16_t GetDlBandwidth() const;

    /**
     * @param bw the downlink bandwidth in RBs
     */
    void SetDlBandwidth(uint16_t bw);

    /**
     * @param cellTypeId for automatic FR configuration
     */
    void SetFrCellTypeId(uint8_t cellTypeId);

    /**
     * @return cellTypeId which is used for automatic FR configuration
     */
    uint8_t GetFrCellTypeId() const;

  protected:
    // inherited from Object
    void DoDispose() override;

    /**
     * @brief Automatic FR reconfiguration
     */
    virtual void Reconfigure() = 0;

    // FFR SAP PROVIDER IMPLEMENTATION

    /**
     * @brief Implementation of LteFfrSapProvider::GetAvailableDlRbg
     * @return vector of size (m_dlBandwidth/RbgSize); false indicates
     *                    that RBG is free to use, true otherwise
     */
    virtual std::vector<bool> DoGetAvailableDlRbg() = 0;

    /**
     * @brief Implementation of LteFfrSapProvider::IsDlRbgAvailableForUe
     * @param rbId
     * @param rnti Radio Network Temporary Identity, an integer identifying the UE
     *             where the report originates from
     * @return true if UE can be served on i-th RB, false otherwise
     */
    virtual bool DoIsDlRbgAvailableForUe(int rbId, uint16_t rnti) = 0;

    /**
     * @brief Implementation of LteFfrSapProvider::GetAvailableUlRbg.
     * @return vector of size m_ulBandwidth; false indicates
     *                    that RB is free to use, true otherwise
     */
    virtual std::vector<bool> DoGetAvailableUlRbg() = 0;

    /**
     * @brief Implementation of LteFfrSapProvider::IsUlRbgAvailableForUe.
     * @param rbId
     * @param rnti Radio Network Temporary Identity, an integer identifying the UE
     *             where the report originates from
     * @return true if UE can be served on i-th RB, false otherwise
     */
    virtual bool DoIsUlRbgAvailableForUe(int rbId, uint16_t rnti) = 0;

    /**
     * @brief DoReportDlCqiInfo
     * @param params
     *
     */
    virtual void DoReportDlCqiInfo(
        const FfMacSchedSapProvider::SchedDlCqiInfoReqParameters& params) = 0;

    /**
     * @brief DoReportUlCqiInfo
     * @param params
     *
     */
    virtual void DoReportUlCqiInfo(
        const FfMacSchedSapProvider::SchedUlCqiInfoReqParameters& params) = 0;

    /**
     * @brief DoReportUlCqiInfo
     * @param ulCqiMap
     *
     */
    virtual void DoReportUlCqiInfo(std::map<uint16_t, std::vector<double>> ulCqiMap) = 0;

    /**
     * @brief DoGetTpc for UE
     * @param rnti
     * @return TPC value
     */
    virtual uint8_t DoGetTpc(uint16_t rnti) = 0;

    /**
     * @brief DoGetMinContinuousUlBandwidth in number of RB
     * @return number of RB in min continuous UL Bandwidth
     */
    virtual uint16_t DoGetMinContinuousUlBandwidth() = 0;

    // FFR SAP RRC PROVIDER IMPLEMENTATION

    /**
     * @brief SetCellId
     * @param cellId the Cell Identifier
     */
    virtual void DoSetCellId(uint16_t cellId);

    /**
     * @brief Implementation of LteFfrRrcSapProvider::SetBandwidth.
     * @param ulBandwidth UL bandwidth in number of RB
     * @param dlBandwidth DL bandwidth in number of RB
     */
    virtual void DoSetBandwidth(uint16_t ulBandwidth, uint16_t dlBandwidth);

    /**
     * @brief Implementation of LteFfrRrcSapProvider::ReportUeMeas.
     * @param rnti Radio Network Temporary Identity, an integer identifying the UE
     *             where the report originates from
     * @param measResults a single report of one measurement identity
     */
    virtual void DoReportUeMeas(uint16_t rnti, LteRrcSap::MeasResults measResults) = 0;

    /**
     * @brief DoRecvLoadInformation
     * @param params
     *
     */
    virtual void DoRecvLoadInformation(EpcX2Sap::LoadInformationParams params) = 0;

    /**
     * @brief Get RBG size for DL Bandwidth according to table 7.1.6.1-1 of 36.213
     * @param dlbandwidth
     * @return size of RBG in number of RB
     */
    int GetRbgSize(int dlbandwidth);

    uint16_t m_cellId; /**< cell ID */

    uint8_t m_dlBandwidth; /**< downlink bandwidth in RBs */
    uint8_t m_ulBandwidth; /**< uplink bandwidth in RBs */

    uint8_t m_frCellTypeId; /**< FFR cell type ID for automatic configuration */

    bool m_enabledInUplink; /**< If true FR algorithm will also work in Uplink*/

    bool m_needReconfiguration; /**< If true FR algorithm will be reconfigured*/
};

} // namespace ns3

#endif /* LTE_FFR_ALGORITHM_H */
