/*
    Copyright (C) 2014 CSP Innovazione nelle ICT s.c.a r.l. (http://www.csp.it/)
    Copyright (C) 2017 Matthias P. Braendli (http://www.opendigitalradio.org)
    Copyright (C) 2015 Data Path

    This program 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.

    This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

    Authors:
         Sergio Sagliocco <sergio.sagliocco@csp.it>
         Matthias P. Braendli <matthias@mpb.li>
                   / |  |-  ')|)  |-|_ _ (|,_   .|  _  ,_ \
         Data Path \(|(||_(|/_| (||_||(a)_||||(|||.(_()|||/

*/

#include "figs.hpp"
#include <cstdio>
#include <vector>
#include <algorithm>

static std::vector<int> subchannels_seen;

bool fig0_1_is_complete(fig0_common_t& fig0, int subch_id)
{
    bool complete = std::count(subchannels_seen.begin(), subchannels_seen.end(), subch_id) > 0;

    if (complete) {
        fig0.wm_decoder.push_fig0_1_bit(subchannels_seen.front() < subchannels_seen.back());
        subchannels_seen.clear();
    }
    else {
        subchannels_seen.push_back(subch_id);
    }

    return complete;
}

// FIG 0/1 Basic sub-channel organization
// ETSI EN 300 401 6.2.1
fig_result_t fig0_1(fig0_common_t& fig0, const display_settings_t &disp)
{
    int i = 1;
    uint8_t* f = fig0.f;
    fig_result_t r;

    while (i <= fig0.figlen-3) {
        // iterate over subchannels
        int subch_id = f[i] >> 2;
        r.complete |= fig0_1_is_complete(fig0, subch_id);

        int start_addr = ((f[i] & 0x03) << 8) |
            (f[i+1]);
        int long_flag  = (f[i+2] >> 7);

        if (fig0.fibcrccorrect) {
            auto& subch = fig0.ensemble.get_or_create_subchannel(subch_id);

            subch.id = subch_id;
            subch.start_addr = start_addr;
            subch.protection_type = long_flag ?
                ensemble_database::subchannel_t::protection_type_t::EEP :
                ensemble_database::subchannel_t::protection_type_t::UEP;
        }

        r.msgs.emplace_back("-");

        if (long_flag) {
            int option = (f[i+2] >> 4) & 0x07;
            int protection_level = (f[i+2] >> 2) & 0x03;
            int subchannel_size  = ((f[i+2] & 0x03) << 8 ) |
                                     f[i+3];
            i += 4;

            r.msgs.emplace_back(1, strprintf("Subch=0x%x", subch_id));
            r.msgs.emplace_back(1, strprintf("start_addr=%d", start_addr));
            r.msgs.emplace_back(1, "form=long");

            if (option == 0x00) {
                r.msgs.emplace_back(1, strprintf("EEP=%d-A", protection_level+1));
            }
            else if (option == 0x01) {
                r.msgs.emplace_back(1, strprintf("EEP=%d-B", protection_level+1));
            }
            else {
                r.errors.emplace_back(strprintf("Invalid option %d protection %d",
                            option, protection_level));
            }

            r.msgs.emplace_back(1, strprintf("subch size=%d", subchannel_size));

            if (fig0.fibcrccorrect) {
                auto& subch = fig0.ensemble.get_subchannel(subch_id);
                using ensemble_database::subchannel_t;
                using eep_t = subchannel_t::protection_eep_option_t;
                if (option == 0x00) {
                    subch.protection_option = eep_t::EEP_A;
                }
                else {
                    subch.protection_option = eep_t::EEP_B;
                }
                subch.protection_level = protection_level;
                subch.size = subchannel_size;
            }
        }
        else {
            int table_switch = (f[i+2] >> 6) & 0x01;
            uint32_t table_index  = (f[i+2] & 0x3F);

            r.msgs.emplace_back(1, strprintf("Subch=0x%x", subch_id));
            r.msgs.emplace_back(1, strprintf("start_addr=%d", start_addr));
            r.msgs.emplace_back(1, "form=short");
            if (table_switch != 0) {
                r.errors.emplace_back(strprintf("Invalid table_switch %d", table_switch));
            }
            r.msgs.emplace_back(1, strprintf("table index=%d", table_index));

            if (fig0.fibcrccorrect) {
                auto& subch = fig0.ensemble.get_subchannel(subch_id);
                subch.table_switch = table_switch;
                subch.table_index = table_index;
            }

            i += 3;
        }
    }

    return r;
}