/*
 * Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
 * Copyright (C) 2016 Furrtek
 * Copyright (C) 2023 gullradriel, Nilorea Studio Inc.
 *
 * This file is part of PortaPack.
 *
 * 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 2, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include "freqman.hpp"
#include <algorithm>

using option_t = std::pair<std::string, int32_t>;
using options_t = std::vector<option_t>;

options_t freqman_entry_modulations = {
    {"AM", 0},
    {"NFM", 1},
    {"WFM", 2}};

options_t freqman_entry_bandwidths[4] = {
    {// AM
     {"DSB 9k", 0},
     {"DSB 6k", 1},
     {"USB+3k", 2},
     {"LSB-3k", 3},
     {"CW", 4}},
    {// NFM
     {"8k5", 0},
     {"11k", 1},
     {"16k", 2}},
    {
        // WFM
        {"200k", 0},
        {"180k", 1},
        {"40k", 2},
    }};

options_t freqman_entry_steps = {
    {"0.1kHz      ", 100},
    {"1kHz        ", 1000},
    {"5kHz (SA AM)", 5000},
    {"6.25kHz(NFM)", 6250},
    {"8.33kHz(AIR)", 8330},
    {"9kHz (EU AM)", 9000},
    {"10kHz(US AM)", 10000},
    {"12.5kHz(NFM)", 12500},
    {"15kHz  (HFM)", 15000},
    {"25kHz   (N1)", 25000},
    {"30kHz (OIRT)", 30000},
    {"50kHz  (FM1)", 50000},
    {"100kHz (FM2)", 100000},
    {"250kHz  (N2)", 250000},
    {"500kHz (WFM)", 500000},
    {"1MHz        ", 1000000}};

options_t freqman_entry_steps_short = {
    {"0.1kHz", 100},
    {"1kHz", 1000},
    {"5kHz", 5000},
    {"6.25kHz", 6250},
    {"8.33kHz", 8330},
    {"9kHz", 9000},
    {"10kHz", 10000},
    {"12.5kHz", 12500},
    {"15kHz", 15000},
    {"25kHz", 25000},
    {"30kHz", 30000},
    {"50kHz", 50000},
    {"100kHz", 100000},
    {"250kHz", 250000},
    {"500kHz", 500000},
    {"1MHz", 1000000}};

std::vector<std::string> get_freqman_files() {
    std::vector<std::string> file_list;

    auto files = scan_root_files(u"FREQMAN", u"*.TXT");

    for (auto file : files) {
        std::string file_name = file.stem().string();
        // don't propose tmp / hidden files in freqman's list
        if (file_name.length() && file_name[0] != '.') {
            file_list.emplace_back(file_name);
        }
    }

    return file_list;
};

bool load_freqman_file(std::string& file_stem, freqman_db& db) {
    return load_freqman_file_ex(file_stem, db, true, true, true);
}

bool load_freqman_file_ex(std::string& file_stem, freqman_db& db, bool load_freqs, bool load_ranges, bool load_hamradios) {
    File freqman_file;
    size_t length, n = 0, file_position = 0;
    char* pos;
    char* line_start;
    char* line_end;
    std::string description;
    rf::Frequency frequency_a, frequency_b;
    const int read_buf_size = 128;
    char file_data[read_buf_size + 1];
    freqman_entry_type type;
    freqman_index_t modulation = 0;
    freqman_index_t bandwidth = 0;
    freqman_index_t step = 0;
    freqman_index_t tone = 0;

    // these are not enough to really start with a new, clean, empty vector
    // swap is the only way to achieve a perfect memory liberation
    // db.clear();
    // db.shrink_to_fit():
    std::vector<freqman_entry>().swap(db);

    auto result = freqman_file.open("FREQMAN/" + file_stem + ".TXT");
    if (result.is_valid())
        return false;

    while (1) {
        // Read a read_buf_size bytes block from file
        freqman_file.seek(file_position);

        memset(file_data, 0, read_buf_size + 1);
        auto read_size = freqman_file.read(file_data, read_buf_size);
        if (read_size.is_error())
            return false;  // Read error

        file_position += read_buf_size;

        // Reset line_start to beginning of buffer
        line_start = file_data;

        // If EOF reached, insert 0x0A after, in case the last line doesn't have a C/R
        if (read_size.value() < read_buf_size)
            *(line_start + read_size.value()) = 0x0A;

        // Look for complete lines in buffer
        while ((line_end = strstr(line_start, "\x0A"))) {
            *line_end = 0;  // Stop strstr() searches below at EOL
            modulation = -1;
            bandwidth = -1;
            step = -1;
            tone = -1;
            type = ERROR_TYPE;

            frequency_a = frequency_b = 0;
            // Read frequency
            pos = strstr(line_start, "f=");
            if (pos) {
                pos += 2;
                frequency_a = strtoll(pos, nullptr, 10);
                type = SINGLE;
            } else {
                // ...or range
                pos = strstr(line_start, "a=");
                if (pos) {
                    pos += 2;
                    frequency_a = strtoll(pos, nullptr, 10);
                    type = RANGE;
                    pos = strstr(line_start, "b=");
                    if (pos) {
                        pos += 2;
                        frequency_b = strtoll(pos, nullptr, 10);
                    } else
                        frequency_b = 0;
                } else {
                    // ... or hamradio
                    pos = strstr(line_start, "r=");
                    if (pos) {
                        pos += 2;
                        frequency_a = strtoll(pos, nullptr, 10);
                        type = HAMRADIO;
                        pos = strstr(line_start, "t=");
                        if (pos) {
                            pos += 2;
                            frequency_b = strtoll(pos, nullptr, 10);
                        } else
                            frequency_b = frequency_a;
                    } else
                        frequency_a = 0;
                }
            }
            // modulation if any
            pos = strstr(line_start, "m=");
            if (pos) {
                pos += 2;
                modulation = freqman_entry_get_modulation_from_str(pos);
            }
            // bandwidth if any
            pos = strstr(line_start, "bw=");
            if (pos) {
                pos += 3;
                bandwidth = freqman_entry_get_bandwidth_from_str(modulation, pos);
            }
            // step if any
            pos = strstr(line_start, "s=");
            if (pos) {
                pos += 2;
                step = freqman_entry_get_step_from_str_short(pos);
            }
            // ctcss tone if any
            /* disabled until better form
               pos = strstr(line_start, "c=");
               if (pos) {
               pos += 2;
               tone = tone_key_index_by_value( strtoll( pos , nullptr , 10 ) );
               } */
            // Read description until , or LF
            pos = strstr(line_start, "d=");
            if (pos) {
                pos += 2;
                length = std::min(strcspn(pos, ",\x0A"), (size_t)FREQMAN_DESC_MAX_LEN);
                description = string(pos, length);
            }
            if ((type == SINGLE && load_freqs) || (type == RANGE && load_ranges) || (type == HAMRADIO && load_hamradios)) {
                db.push_back({frequency_a, frequency_b, description, type, modulation, bandwidth, step, tone});
                n++;
                if (n > FREQMAN_MAX_PER_FILE) return true;
            }

            line_start = line_end + 1;
            if (line_start - file_data >= read_buf_size) break;
        }

        if (read_size.value() != read_buf_size)
            break;  // End of file

        // Restart at beginning of last incomplete line
        file_position -= (file_data + read_buf_size - line_start);
    }

    /* populate implicitly specified modulation / bandwidth */
    if (db.size() > 2) {
        modulation = db[0].modulation;
        bandwidth = db[0].bandwidth;

        for (unsigned int it = 1; it < db.size(); it++) {
            if (db[it].modulation < 0) {
                db[it].modulation = modulation;
            } else {
                modulation = db[it].modulation;
            }
            if (db[it].bandwidth < 0) {
                db[it].bandwidth = bandwidth;
            } else {
                modulation = db[it].bandwidth;
            }
        }
    }
    return true;
}

bool get_freq_string(freqman_entry& entry, std::string& item_string) {
    rf::Frequency frequency_a, frequency_b;

    frequency_a = entry.frequency_a;
    if (entry.type == SINGLE) {
        // Single
        item_string = "f=" + to_string_dec_uint(frequency_a / 1000) + to_string_dec_uint(frequency_a % 1000UL, 3, '0');
    } else if (entry.type == RANGE) {
        // Range
        frequency_b = entry.frequency_b;
        item_string = "a=" + to_string_dec_uint(frequency_a / 1000) + to_string_dec_uint(frequency_a % 1000UL, 3, '0');
        item_string += ",b=" + to_string_dec_uint(frequency_b / 1000) + to_string_dec_uint(frequency_b % 1000UL, 3, '0');
        if (entry.step >= 0) {
            item_string += ",s=" + freqman_entry_get_step_string_short(entry.step);
        }
    } else if (entry.type == HAMRADIO) {
        frequency_b = entry.frequency_b;
        item_string = "r=" + to_string_dec_uint(frequency_a / 1000) + to_string_dec_uint(frequency_a % 1000UL, 3, '0');
        item_string += ",t=" + to_string_dec_uint(frequency_b / 1000) + to_string_dec_uint(frequency_b % 1000UL, 3, '0');
        if (entry.tone >= 0) {
            item_string += ",c=" + tone_key_string(entry.tone);
        }
    }
    if (entry.modulation >= 0 && (unsigned)entry.modulation < freqman_entry_modulations.size()) {
        item_string += ",m=" + freqman_entry_get_modulation_string(entry.modulation);
        if (entry.bandwidth >= 0 && (unsigned)entry.bandwidth < freqman_entry_bandwidths[entry.modulation].size()) {
            item_string += ",bw=" + freqman_entry_get_bandwidth_string(entry.modulation, entry.bandwidth);
        }
    }
    if (entry.description.size())
        item_string += ",d=" + entry.description;

    return true;
}

bool save_freqman_file(std::string& file_stem, freqman_db& db) {
    File freqman_file;

    std::string freq_file_path = "FREQMAN/" + file_stem + ".TXT";
    std::string tmp_freq_file_path = "FREQMAN/" + file_stem + ".TXT.TMP";

    if (!db.size()) {
        delete_file("FREQMAN/" + file_stem + ".TXT");
        return true;
    }

    delete_file(tmp_freq_file_path);
    auto result = freqman_file.open(tmp_freq_file_path);
    if (!result.is_valid()) {
        for (size_t n = 0; n < db.size(); n++) {
            std::string item_string;
            auto& entry = db[n];
            get_freq_string(entry, item_string);
            freqman_file.write_line(item_string);
        }
        delete_file(freq_file_path);
        rename_file(tmp_freq_file_path, freq_file_path);
        return true;
    }
    return false;
}

bool create_freqman_file(std::string& file_stem, File& freqman_file) {
    auto result = freqman_file.create("FREQMAN/" + file_stem + ".TXT");

    if (result.is_valid())
        return false;

    return true;
}

std::string freqman_item_string(freqman_entry& entry, size_t max_length) {
    std::string item_string;

    switch (entry.type) {
        case SINGLE:
            item_string = to_string_short_freq(entry.frequency_a) + "M: " + entry.description;
            break;
        case RANGE:
            item_string = "R: " + entry.description;
            break;
        case HAMRADIO:
            item_string = "H: " + entry.description;
            break;
        default:
            item_string = "!UNKNOW TYPE " + entry.description;
            break;
    }

    if (item_string.size() > max_length)
        return item_string.substr(0, max_length - 3) + "...";

    return item_string;
}

void freqman_set_modulation_option(OptionsField& option) {
    option.set_options(freqman_entry_modulations);
}

void freqman_set_bandwidth_option(freqman_index_t modulation, OptionsField& option) {
    option.set_options(freqman_entry_bandwidths[modulation]);
}

void freqman_set_step_option(OptionsField& option) {
    option.set_options(freqman_entry_steps);
}

void freqman_set_step_option_short(OptionsField& option) {
    option.set_options(freqman_entry_steps_short);
}

std::string freqman_entry_get_modulation_string(freqman_index_t modulation) {
    if (modulation < 0 || (unsigned)modulation >= freqman_entry_modulations.size()) {
        return std::string("");  // unknown modulation
    }
    return freqman_entry_modulations[modulation].first;
}

std::string freqman_entry_get_bandwidth_string(freqman_index_t modulation, freqman_index_t bandwidth) {
    if (modulation < 0 || (unsigned)modulation >= freqman_entry_modulations.size()) {
        return std::string("");  // unknown modulation
    }
    if (bandwidth < 0 || (unsigned)bandwidth > freqman_entry_bandwidths[modulation].size()) {
        return std::string("");  // unknown modulation
    }
    return freqman_entry_bandwidths[modulation][bandwidth].first;
}

std::string freqman_entry_get_step_string(freqman_index_t step) {
    if (step < 0 || (unsigned)step >= freqman_entry_steps.size()) {
        return std::string("");  // unknown modulation
    }
    return freqman_entry_steps[step].first;
}

std::string freqman_entry_get_step_string_short(freqman_index_t step) {
    if (step < 0 || (unsigned)step >= freqman_entry_steps_short.size()) {
        return std::string("");  // unknown modulation
    }
    return freqman_entry_steps_short[step].first;
}

int32_t freqman_entry_get_modulation_value(freqman_index_t modulation) {
    if (modulation < 0 || (unsigned)modulation >= freqman_entry_modulations.size()) {
        return -1;  // unknown modulation
    }
    return freqman_entry_modulations[modulation].second;
}

int32_t freqman_entry_get_bandwidth_value(freqman_index_t modulation, freqman_index_t bandwidth) {
    if (modulation < 0 || (unsigned)modulation >= freqman_entry_modulations.size()) {
        return -1;  // unknown modulation
    }
    if (bandwidth < 0 || (unsigned)bandwidth > freqman_entry_bandwidths[modulation].size()) {
        return -1;  // unknown bandwidth for modulation
    }
    return freqman_entry_bandwidths[modulation][bandwidth].second;
}

int32_t freqman_entry_get_step_value(freqman_index_t step) {
    if (step < 0 || (unsigned)step >= freqman_entry_steps.size()) {
        return -1;  // unknown modulation
    }
    return freqman_entry_steps[step].second;
}

freqman_index_t freqman_entry_get_modulation_from_str(char* str) {
    if (!str)
        return -1;
    for (freqman_index_t index = 0; (unsigned)index < freqman_entry_modulations.size(); index++) {
        if (strncmp(freqman_entry_modulations[index].first.c_str(), str, freqman_entry_modulations[index].first.size()) == 0)
            return index;
    }
    return -1;
}

freqman_index_t freqman_entry_get_bandwidth_from_str(freqman_index_t modulation, char* str) {
    if (!str)
        return -1;
    if (modulation < 0 || (unsigned)modulation >= freqman_entry_modulations.size())
        return -1;
    for (freqman_index_t index = 0; (unsigned)index < freqman_entry_bandwidths[modulation].size(); index++) {
        if (strncmp(freqman_entry_bandwidths[modulation][index].first.c_str(), str, freqman_entry_bandwidths[modulation][index].first.size()) == 0)
            return index;
    }
    return -1;
}

freqman_index_t freqman_entry_get_step_from_str(char* str) {
    if (!str)
        return -1;
    for (freqman_index_t index = 0; (unsigned)index < freqman_entry_steps.size(); index++) {
        if (strncmp(freqman_entry_steps[index].first.c_str(), str, freqman_entry_steps[index].first.size()) == 0)
            return index;
    }
    return -1;
}

freqman_index_t freqman_entry_get_step_from_str_short(char* str) {
    if (!str)
        return -1;
    for (freqman_index_t index = 0; (unsigned)index < freqman_entry_steps_short.size(); index++) {
        if (strncmp(freqman_entry_steps_short[index].first.c_str(), str, freqman_entry_steps_short[index].first.size()) == 0)
            return index;
    }
    return -1;
}