#include "settings.h"

#include "ipv4.h"

namespace roro {

namespace {

enum class Kind : uint8_t { Bool, Int, String };

struct Definition {
    const char* key;
    Kind kind;
    int32_t defaultInt;
    const char* defaultString;
    int32_t min;
    int32_t max;  // for strings: max length in bytes
};

// Order must match the Setting enum.
const Definition kDefinitions[] = {
    {"setup_done", Kind::Bool, 0, nullptr, 0, 1},
    {"long_name", Kind::String, 0, "", 1, 39},
    {"short_name", Kind::String, 0, "", 1, 4},
    {"region", Kind::String, 0, "EU868", 1, 8},
    {"region_ok", Kind::Bool, 0, nullptr, 0, 1},
    {"timezone", Kind::String, 0, "CET-1CEST,M3.5.0,M10.5.0/3", 1, 63},
    {"brightness", Kind::Int, 60, nullptr, 10, 100},
    {"dim_s", Kind::Int, 30, nullptr, 5, 600},
    {"off_s", Kind::Int, 60, nullptr, 10, 3600},
    {"sound", Kind::Bool, 1, nullptr, 0, 1},
    {"probe_mac_raw", Kind::Bool, 1, nullptr, 0, 1},
    {"wifi_on", Kind::Bool, 1, nullptr, 0, 1},
    {"gnss_on", Kind::Bool, 1, nullptr, 0, 1},
    {"coord_dms", Kind::Bool, 0, nullptr, 0, 1},
    {"lora_preset", Kind::Int, 0, nullptr, 0, 6},  // LongFast first
    {"dns1", Kind::String, 0, "9.9.9.9", 7, 15},  // Quad9
    {"dns2", Kind::String, 0, "1.1.1.1", 0, 15},  // Cloudflare
    {"dns_always", Kind::Bool, 0, nullptr, 0, 1},
    {"ntp1", Kind::String, 0, "pool.ntp.org", 1, 63},
    {"ntp2", Kind::String, 0, "time.cloudflare.com", 0, 63},
    {"gnss_quiet", Kind::Bool, 0, nullptr, 0, 1},  // off: GNSS stays on, as decided in M2 (Q58)
};
static_assert(sizeof(kDefinitions) / sizeof(kDefinitions[0]) == static_cast<size_t>(Setting::Count),
              "every Setting needs a definition");

const char* const kKnownRegions[] = {"EU868"};

const Definition& def(Setting s) { return kDefinitions[static_cast<size_t>(s)]; }

}  // namespace

Settings::Settings(KeyValueStore& store, EventBus& bus) : store_(store), bus_(bus) {}

const char* Settings::key(Setting s) { return def(s).key; }

void Settings::load() {
    for (size_t i = 0; i < values_.size(); i++) {
        auto s = static_cast<Setting>(i);
        const auto& d = def(s);
        auto& v = values_[i];
        if (d.kind == Kind::String) {
            v.str = d.defaultString;
            std::string stored;
            if (store_.getString(d.key, stored) && validString(s, stored)) v.str = stored;
        } else {
            v.i = d.defaultInt;
            int32_t stored;
            if (store_.getInt(d.key, stored) && validInt(s, stored)) v.i = stored;
        }
    }
}

int32_t Settings::getInt(Setting s) const { return values_[static_cast<size_t>(s)].i; }
bool Settings::getBool(Setting s) const { return getInt(s) != 0; }
const std::string& Settings::getString(Setting s) const { return values_[static_cast<size_t>(s)].str; }

bool Settings::validInt(Setting s, int32_t value) const {
    const auto& d = def(s);
    if (d.kind == Kind::String || value < d.min || value > d.max) return false;
    if (s == Setting::DimTimeoutS) return value < getInt(Setting::OffTimeoutS);
    if (s == Setting::OffTimeoutS) return value > getInt(Setting::DimTimeoutS);
    return true;
}

bool Settings::validString(Setting s, const std::string& value) const {
    const auto& d = def(s);
    if (d.kind != Kind::String) return false;
    if (value.size() < static_cast<size_t>(d.min) || value.size() > static_cast<size_t>(d.max)) return false;
    if (s == Setting::Region) {
        for (auto region : kKnownRegions)
            if (value == region) return true;
        return false;
    }
    uint32_t address;
    if (s == Setting::Dns1) return net::parseIpv4(value, address);
    if (s == Setting::Dns2) return value.empty() || net::parseIpv4(value, address);
    if (s == Setting::Ntp1) return net::validHost(value);
    if (s == Setting::Ntp2) return value.empty() || net::validHost(value);
    return true;
}

bool Settings::setInt(Setting s, int32_t value) {
    if (def(s).kind == Kind::Bool) return false;
    if (!validInt(s, value)) return false;
    if (getInt(s) == value) return true;
    values_[static_cast<size_t>(s)].i = value;
    store_.putInt(key(s), value);
    changed(s);
    return true;
}

bool Settings::setBool(Setting s, bool value) {
    if (def(s).kind != Kind::Bool) return false;
    if (getBool(s) == value) return true;
    values_[static_cast<size_t>(s)].i = value ? 1 : 0;
    store_.putInt(key(s), value ? 1 : 0);
    changed(s);
    return true;
}

bool Settings::setString(Setting s, const std::string& value) {
    if (!validString(s, value)) return false;
    if (getString(s) == value) return true;
    values_[static_cast<size_t>(s)].str = value;
    store_.putString(key(s), value);
    changed(s);
    return true;
}

void Settings::changed(Setting s) {
    bus_.publish(Event::withText(EventType::SettingChanged, key(s), static_cast<int32_t>(s)));
}

}  // namespace roro