/*
   Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
   2011, 2012 Her Majesty the Queen in Right of Canada (Communications
   Research Center Canada)

   Copyright (C) 2016
   Matthias P. Braendli, matthias.braendli@mpb.li
   */
/*
   This file is part of ODR-DabMux.

   ODR-DabMux is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as
   published by the Free Software Foundation, either version 3 of the
   License, or (at your option) any later version.

   ODR-DabMux is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with ODR-DabMux.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "fig/FIG0structs.h"
#include "fig/FIG0_8.h"
#include "utils.h"

namespace FIC {

struct FIGtype0_8_short {
    uint8_t SCIdS:4;
    uint8_t rfa_1:3;
    uint8_t ext:1;
    uint8_t Id:6;
    uint8_t MscFic:1;
    uint8_t LS:1;
    uint8_t rfa_2;
} PACKED;

struct FIGtype0_8_long {
    uint8_t SCIdS:4;
    uint8_t rfa_1:3;
    uint8_t ext:1;
    uint8_t SCId_high:4;
    uint8_t rfa:3;
    uint8_t LS:1;
    uint8_t SCId_low;
    uint8_t rfa_2;
    void setSCId(uint16_t id) {
        SCId_high = id >> 8;
        SCId_low = id & 0xff;
    }
    uint16_t getSCid() {
        return (SCId_high << 8) | SCId_low;
    }
} PACKED;

FIG0_8::FIG0_8(FIGRuntimeInformation *rti, FIG0_8_mode mode) :
    m_rti(rti),
    m_mode(mode),
    m_initialised(false),
    // In Programme mode the first (and only) pass emits programme components;
    // in Data mode it emits data components; in Both mode it alternates as the
    // original implementation did, starting on the data pass.
    m_transmit_programme(mode == FIG0_8_mode::Programme)
{
}

FillStatus FIG0_8::fill(uint8_t *buf, size_t max_size)
{
    FillStatus fs;
    auto ensemble = m_rti->ensemble;
    ssize_t remaining = max_size;

    if (not m_initialised) {
        componentFIG0_8 = m_rti->ensemble->components.end();
        m_initialised = true;
    }

    FIGtype0* fig0 = NULL;

    for (; componentFIG0_8 != ensemble->components.end();
            ++componentFIG0_8) {

        auto service = getService(*componentFIG0_8,
                ensemble->services);
        auto subchannel = getSubchannel(ensemble->subchannels,
                (*componentFIG0_8)->subchId);

        if (subchannel == ensemble->subchannels.end()) {
            etiLog.log(error,
                    "Subchannel %i does not exist for component "
                    "of service %i",
                    (*componentFIG0_8)->subchId,
                    (*componentFIG0_8)->serviceId);
            continue;
        }

        if (m_transmit_programme and (*service)->isProgramme(ensemble)) {
            const int required_size =
                ((*subchannel)->type == subchannel_type_t::Packet ? 5 : 4);

            if (fig0 == NULL) {
                if (remaining < 2 + required_size) {
                    break;
                }
                fig0 = (FIGtype0*)buf;
                fig0->FIGtypeNumber = 0;
                fig0->Length = 1;
                fig0->CN = 0;
                fig0->OE = 0;
                fig0->PD = 0;
                fig0->Extension = 8;
                buf += 2;
                remaining -= 2;
            }
            else if (remaining < required_size) {
                break;
            }

            if ((*subchannel)->type == subchannel_type_t::Packet) { // Data packet
                buf[0] = ((*componentFIG0_8)->serviceId >> 8) & 0xFF;
                buf[1] = ((*componentFIG0_8)->serviceId) & 0xFF;
                fig0->Length += 2;
                buf += 2;
                remaining -= 2;

                FIGtype0_8_long* definition = (FIGtype0_8_long*)buf;
                memset(definition, 0, 3);
                definition->ext = 0;    // no rfa
                definition->SCIdS = (*componentFIG0_8)->SCIdS;
                definition->LS = 1;
                definition->setSCId((*componentFIG0_8)->packet.id);
                fig0->Length += 3;
                buf += 3;             // 8 minus rfa
                remaining -= 3;
            }
            else {    // Audio, data stream
                buf[0] = ((*componentFIG0_8)->serviceId >> 8) & 0xFF;
                buf[1] = ((*componentFIG0_8)->serviceId) & 0xFF;

                fig0->Length += 2;
                buf += 2;
                remaining -= 2;

                FIGtype0_8_short* definition = (FIGtype0_8_short*)buf;
                memset(definition, 0, 2);
                definition->ext = 0;    // no rfa
                definition->SCIdS = (*componentFIG0_8)->SCIdS;
                definition->LS = 0;
                definition->MscFic = 0;
                definition->Id = (*componentFIG0_8)->subchId;
                fig0->Length += 2;
                buf += 2;             // 4 minus rfa
                remaining -= 2;
            }
        }
        else if (!m_transmit_programme and !(*service)->isProgramme(ensemble)) {
            // Data
            const int required_size =
                ((*subchannel)->type == subchannel_type_t::Packet ? 7 : 6);

            if (fig0 == NULL) {
                if (remaining < 2 + required_size) {
                    break;
                }
                fig0 = (FIGtype0*)buf;
                fig0->FIGtypeNumber = 0;
                fig0->Length = 1;
                fig0->CN = 0;
                fig0->OE = 0;
                fig0->PD = 1;
                fig0->Extension = 8;
                buf += 2;
                remaining -= 2;
            }
            else if (remaining < required_size) {
                break;
            }

            if ((*subchannel)->type == subchannel_type_t::Packet) { // Data packet
                buf[0] = ((*componentFIG0_8)->serviceId >> 24) & 0xFF;
                buf[1] = ((*componentFIG0_8)->serviceId >> 16) & 0xFF;
                buf[2] = ((*componentFIG0_8)->serviceId >> 8) & 0xFF;
                buf[3] = ((*componentFIG0_8)->serviceId) & 0xFF;
                fig0->Length += 4;
                buf += 4;
                remaining -= 4;

                FIGtype0_8_long* definition = (FIGtype0_8_long*)buf;
                memset(definition, 0, 3);
                definition->ext = 0;    // no rfa
                definition->SCIdS = (*componentFIG0_8)->SCIdS;
                definition->LS = 1;
                definition->setSCId((*componentFIG0_8)->packet.id);
                fig0->Length += 3;
                buf += 3;             // 8 minus rfa
                remaining -= 3;
            }
            else {    // Audio, data stream
                buf[0] = ((*componentFIG0_8)->serviceId >> 24) & 0xFF;
                buf[1] = ((*componentFIG0_8)->serviceId >> 16) & 0xFF;
                buf[2] = ((*componentFIG0_8)->serviceId >> 8) & 0xFF;
                buf[3] = ((*componentFIG0_8)->serviceId) & 0xFF;
                fig0->Length += 4;
                buf += 4;
                remaining -= 4;

                FIGtype0_8_short* definition = (FIGtype0_8_short*)buf;
                memset(definition, 0, 2);
                definition->ext = 0;    // no rfa
                definition->SCIdS = (*componentFIG0_8)->SCIdS;
                definition->LS = 0;
                definition->MscFic = 0;
                definition->Id = (*componentFIG0_8)->subchId;
                fig0->Length += 2;
                buf += 2;             // 4 minus rfa
                remaining -= 2;
            }
        }
    }

    if (componentFIG0_8 == ensemble->components.end()) {
        componentFIG0_8 = ensemble->components.begin();

        if (m_mode == FIG0_8_mode::Both) {
            // Legacy behaviour: the full database is sent every second full
            // loop, alternating programme and data passes.
            fs.complete_fig_transmitted = m_transmit_programme;
            m_transmit_programme = not m_transmit_programme;
            // Alternate between data and programme FIG0/8, do not mix fig0
            // with PD=0 with extension 8 stuff that actually needs PD=1, and
            // vice versa.
        }
        else {
            // Split mode: this instance carries a single component class, so
            // one full loop is one complete cycle. m_transmit_programme is
            // fixed for the lifetime of the instance and is never toggled.
            fs.complete_fig_transmitted = true;
        }
    }

    fs.num_bytes_written = max_size - remaining;
    return fs;
}

}
