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

#include "lte-fr-hard-algorithm.h"

#include "ns3/log.h"

namespace ns3
{

NS_LOG_COMPONENT_DEFINE("LteFrHardAlgorithm");

NS_OBJECT_ENSURE_REGISTERED(LteFrHardAlgorithm);

/// FrHardDownlinkDefaultConfiguration structure
struct FrHardDownlinkDefaultConfiguration
{
    uint8_t m_cellId;      ///< cell ID
    uint8_t m_dlBandwidth; ///< DL bandwidth
    uint8_t m_dlOffset;    ///< DL offset
    uint8_t m_dlSubBand;   ///< DL subband
};

/// The hard downlink default configuration
static const FrHardDownlinkDefaultConfiguration g_frHardDownlinkDefaultConfiguration[]{
    {1, 15, 0, 4},
    {2, 15, 4, 4},
    {3, 15, 8, 6},
    {1, 25, 0, 8},
    {2, 25, 8, 8},
    {3, 25, 16, 9},
    {1, 50, 0, 16},
    {2, 50, 16, 16},
    {3, 50, 32, 18},
    {1, 75, 0, 24},
    {2, 75, 24, 24},
    {3, 75, 48, 27},
    {1, 100, 0, 32},
    {2, 100, 32, 32},
    {3, 100, 64, 36},
};

/// FrHardUplinkDefaultConfiguration structure
struct FrHardUplinkDefaultConfiguration
{
    uint8_t m_cellId;      ///< cell ID
    uint8_t m_ulBandwidth; ///< UL bandwidth
    uint8_t m_ulOffset;    ///< Ul offset
    uint8_t m_ulSubBand;   ///< UL subband
};

/// The hard uplink default configuration
static const FrHardUplinkDefaultConfiguration g_frHardUplinkDefaultConfiguration[]{
    {1, 15, 0, 5},
    {2, 15, 5, 5},
    {3, 15, 10, 5},
    {1, 25, 0, 8},
    {2, 25, 8, 8},
    {3, 25, 16, 9},
    {1, 50, 0, 16},
    {2, 50, 16, 16},
    {3, 50, 32, 18},
    {1, 75, 0, 24},
    {2, 75, 24, 24},
    {3, 75, 48, 27},
    {1, 100, 0, 32},
    {2, 100, 32, 32},
    {3, 100, 64, 36},
};

/** @returns number of downlink configurations */
const uint16_t NUM_DOWNLINK_CONFS(sizeof(g_frHardDownlinkDefaultConfiguration) /
                                  sizeof(FrHardDownlinkDefaultConfiguration));
/** @returns number of uplink configurations */
const uint16_t NUM_UPLINK_CONFS(sizeof(g_frHardUplinkDefaultConfiguration) /
                                sizeof(FrHardUplinkDefaultConfiguration));

LteFrHardAlgorithm::LteFrHardAlgorithm()
    : m_ffrSapUser(nullptr),
      m_ffrRrcSapUser(nullptr),
      m_dlOffset(0),
      m_dlSubBand(0),
      m_ulOffset(0),
      m_ulSubBand(0)
{
    NS_LOG_FUNCTION(this);
    m_ffrSapProvider = new MemberLteFfrSapProvider<LteFrHardAlgorithm>(this);
    m_ffrRrcSapProvider = new MemberLteFfrRrcSapProvider<LteFrHardAlgorithm>(this);
}

LteFrHardAlgorithm::~LteFrHardAlgorithm()
{
    NS_LOG_FUNCTION(this);
}

void
LteFrHardAlgorithm::DoDispose()
{
    NS_LOG_FUNCTION(this);
    delete m_ffrSapProvider;
    delete m_ffrRrcSapProvider;
}

TypeId
LteFrHardAlgorithm::GetTypeId()
{
    static TypeId tid =
        TypeId("ns3::LteFrHardAlgorithm")
            .SetParent<LteFfrAlgorithm>()
            .SetGroupName("Lte")
            .AddConstructor<LteFrHardAlgorithm>()
            .AddAttribute("UlSubBandOffset",
                          "Uplink Offset in number of Resource Block Groups",
                          UintegerValue(0),
                          MakeUintegerAccessor(&LteFrHardAlgorithm::m_ulOffset),
                          MakeUintegerChecker<uint8_t>())
            .AddAttribute(
                "UlSubBandwidth",
                "Uplink Transmission SubBandwidth Configuration in number of Resource Block Groups",
                UintegerValue(25),
                MakeUintegerAccessor(&LteFrHardAlgorithm::m_ulSubBand),
                MakeUintegerChecker<uint8_t>())
            .AddAttribute("DlSubBandOffset",
                          "Downlink Offset in number of Resource Block Groups",
                          UintegerValue(0),
                          MakeUintegerAccessor(&LteFrHardAlgorithm::m_dlOffset),
                          MakeUintegerChecker<uint8_t>())
            .AddAttribute("DlSubBandwidth",
                          "Downlink Transmission SubBandwidth Configuration in number of Resource "
                          "Block Groups",
                          UintegerValue(25),
                          MakeUintegerAccessor(&LteFrHardAlgorithm::m_dlSubBand),
                          MakeUintegerChecker<uint8_t>());
    return tid;
}

void
LteFrHardAlgorithm::SetLteFfrSapUser(LteFfrSapUser* s)
{
    NS_LOG_FUNCTION(this << s);
    m_ffrSapUser = s;
}

LteFfrSapProvider*
LteFrHardAlgorithm::GetLteFfrSapProvider()
{
    NS_LOG_FUNCTION(this);
    return m_ffrSapProvider;
}

void
LteFrHardAlgorithm::SetLteFfrRrcSapUser(LteFfrRrcSapUser* s)
{
    NS_LOG_FUNCTION(this << s);
    m_ffrRrcSapUser = s;
}

LteFfrRrcSapProvider*
LteFrHardAlgorithm::GetLteFfrRrcSapProvider()
{
    NS_LOG_FUNCTION(this);
    return m_ffrRrcSapProvider;
}

void
LteFrHardAlgorithm::DoInitialize()
{
    NS_LOG_FUNCTION(this);
    LteFfrAlgorithm::DoInitialize();

    NS_ASSERT_MSG(m_dlBandwidth > 14, "DlBandwidth must be at least 15 to use FFR algorithms");
    NS_ASSERT_MSG(m_ulBandwidth > 14, "UlBandwidth must be at least 15 to use FFR algorithms");

    if (m_frCellTypeId != 0)
    {
        SetDownlinkConfiguration(m_frCellTypeId, m_dlBandwidth);
        SetUplinkConfiguration(m_frCellTypeId, m_ulBandwidth);
    }
}

void
LteFrHardAlgorithm::Reconfigure()
{
    NS_LOG_FUNCTION(this);
    if (m_frCellTypeId != 0)
    {
        SetDownlinkConfiguration(m_frCellTypeId, m_dlBandwidth);
        SetUplinkConfiguration(m_frCellTypeId, m_ulBandwidth);
    }
    InitializeDownlinkRbgMaps();
    InitializeUplinkRbgMaps();
    m_needReconfiguration = false;
}

void
LteFrHardAlgorithm::SetDownlinkConfiguration(uint16_t cellId, uint8_t bandwidth)
{
    NS_LOG_FUNCTION(this);
    for (uint16_t i = 0; i < NUM_DOWNLINK_CONFS; ++i)
    {
        if ((g_frHardDownlinkDefaultConfiguration[i].m_cellId == cellId) &&
            g_frHardDownlinkDefaultConfiguration[i].m_dlBandwidth == m_dlBandwidth)
        {
            m_dlOffset = g_frHardDownlinkDefaultConfiguration[i].m_dlOffset;
            m_dlSubBand = g_frHardDownlinkDefaultConfiguration[i].m_dlSubBand;
        }
    }
}

void
LteFrHardAlgorithm::SetUplinkConfiguration(uint16_t cellId, uint8_t bandwidth)
{
    NS_LOG_FUNCTION(this);
    for (uint16_t i = 0; i < NUM_UPLINK_CONFS; ++i)
    {
        if ((g_frHardUplinkDefaultConfiguration[i].m_cellId == cellId) &&
            g_frHardUplinkDefaultConfiguration[i].m_ulBandwidth == m_ulBandwidth)
        {
            m_ulOffset = g_frHardUplinkDefaultConfiguration[i].m_ulOffset;
            m_ulSubBand = g_frHardUplinkDefaultConfiguration[i].m_ulSubBand;
        }
    }
}

void
LteFrHardAlgorithm::InitializeDownlinkRbgMaps()
{
    m_dlRbgMap.clear();

    int rbgSize = GetRbgSize(m_dlBandwidth);
    m_dlRbgMap.resize(m_dlBandwidth / rbgSize, true);

    NS_ASSERT_MSG(m_dlOffset <= m_dlBandwidth, "DlOffset higher than DlBandwidth");
    NS_ASSERT_MSG(m_dlSubBand <= m_dlBandwidth, "DlBandwidth higher than DlBandwidth");
    NS_ASSERT_MSG((m_dlOffset + m_dlSubBand) <= m_dlBandwidth,
                  "(DlOffset+DlSubBand) higher than DlBandwidth");

    for (int i = m_dlOffset / rbgSize; i < (m_dlOffset / rbgSize + m_dlSubBand / rbgSize); i++)
    {
        m_dlRbgMap[i] = false;
    }
}

void
LteFrHardAlgorithm::InitializeUplinkRbgMaps()
{
    m_ulRbgMap.clear();

    if (!m_enabledInUplink)
    {
        m_ulRbgMap.resize(m_ulBandwidth, false);
        return;
    }

    m_ulRbgMap.resize(m_ulBandwidth, true);

    NS_ASSERT_MSG(m_ulOffset <= m_ulBandwidth, "UlOffset higher than UlBandwidth");
    NS_ASSERT_MSG(m_ulSubBand <= m_ulBandwidth, "UlBandwidth higher than UlBandwidth");
    NS_ASSERT_MSG((m_ulOffset + m_ulSubBand) <= m_ulBandwidth,
                  "(UlOffset+UlSubBand) higher than UlBandwidth");

    for (uint8_t i = m_ulOffset; i < (m_ulOffset + m_ulSubBand); i++)
    {
        m_ulRbgMap[i] = false;
    }
}

std::vector<bool>
LteFrHardAlgorithm::DoGetAvailableDlRbg()
{
    NS_LOG_FUNCTION(this);

    if (m_needReconfiguration)
    {
        Reconfigure();
    }

    if (m_dlRbgMap.empty())
    {
        InitializeDownlinkRbgMaps();
    }

    return m_dlRbgMap;
}

bool
LteFrHardAlgorithm::DoIsDlRbgAvailableForUe(int rbId, uint16_t rnti)
{
    NS_LOG_FUNCTION(this);
    return !m_dlRbgMap[rbId];
}

std::vector<bool>
LteFrHardAlgorithm::DoGetAvailableUlRbg()
{
    NS_LOG_FUNCTION(this);

    if (m_ulRbgMap.empty())
    {
        InitializeUplinkRbgMaps();
    }

    return m_ulRbgMap;
}

bool
LteFrHardAlgorithm::DoIsUlRbgAvailableForUe(int rbId, uint16_t rnti)
{
    NS_LOG_FUNCTION(this);

    if (!m_enabledInUplink)
    {
        return true;
    }

    return !m_ulRbgMap[rbId];
}

void
LteFrHardAlgorithm::DoReportDlCqiInfo(
    const FfMacSchedSapProvider::SchedDlCqiInfoReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    NS_LOG_WARN("Method should not be called, because it is empty");
}

void
LteFrHardAlgorithm::DoReportUlCqiInfo(
    const FfMacSchedSapProvider::SchedUlCqiInfoReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    NS_LOG_WARN("Method should not be called, because it is empty");
}

void
LteFrHardAlgorithm::DoReportUlCqiInfo(std::map<uint16_t, std::vector<double>> ulCqiMap)
{
    NS_LOG_FUNCTION(this);
    NS_LOG_WARN("Method should not be called, because it is empty");
}

uint8_t
LteFrHardAlgorithm::DoGetTpc(uint16_t rnti)
{
    NS_LOG_FUNCTION(this);
    return 1; // 1 is mapped to 0 for Accumulated mode, and to -1 in Absolute mode TS36.213
              // Table 5.1.1.1-2
}

uint16_t
LteFrHardAlgorithm::DoGetMinContinuousUlBandwidth()
{
    NS_LOG_FUNCTION(this);

    if (!m_enabledInUplink)
    {
        return m_ulBandwidth;
    }

    return m_ulSubBand;
}

void
LteFrHardAlgorithm::DoReportUeMeas(uint16_t rnti, LteRrcSap::MeasResults measResults)
{
    NS_LOG_FUNCTION(this << rnti << (uint16_t)measResults.measId);
    NS_LOG_WARN("Method should not be called, because it is empty");
}

void
LteFrHardAlgorithm::DoRecvLoadInformation(EpcX2Sap::LoadInformationParams params)
{
    NS_LOG_FUNCTION(this);
    NS_LOG_WARN("Method should not be called, because it is empty");
}

} // namespace ns3
