/*
 * main.cpp
 * MontaukOS Network Time Protocol service
 * Copyright (c) 2026 Daniel Hammer
 */

#include <montauk/config.h>
#include <montauk/ntp.h>
#include <montauk/service_log.h>
#include <montauk/string.h>
#include <montauk/syscall.h>
#include <libc/stdio.h>

static constexpr uint64_t RETRY_INTERVAL_MS =
    montauk::ntp::MIN_QUERY_INTERVAL_MS;
static constexpr uint64_t SYNC_INTERVAL_MS = 60ULL * 60ULL * 1000ULL;
static constexpr uint64_t CONFIG_POLL_MS = 5000;

static void log(const char* message) {
    char line[256];
    snprintf(line, sizeof(line), "ntp: %s", message);
    montauk::service_log(line);
}

static bool load_settings(char* server, int server_cap) {
    auto cfg = montauk::config::load("ntp");
    bool enabled = cfg.get_bool("ntp.enabled", true);
    montauk::strncpy(server, cfg.get_string("ntp.server", "pool.ntp.org"),
                     server_cap);
    cfg.destroy();
    if (!server[0])
        montauk::strncpy(server, "pool.ntp.org", server_cap);
    return enabled;
}

extern "C" void _start() {
    log("service started");

    char active_server[128] = {};
    bool was_enabled = false;
    uint64_t next_attempt = 0;

    for (;;) {
        char server[128];
        bool enabled = load_settings(server, sizeof(server));
        bool server_changed = !montauk::streq(server, active_server);
        if (server_changed) {
            montauk::strncpy(active_server, server, sizeof(active_server));
            next_attempt = 0;
        }

        if (!enabled) {
            was_enabled = false;
            next_attempt = 0;
            montauk::sleep_ms(CONFIG_POLL_MS);
            continue;
        }
        if (!was_enabled) {
            was_enabled = true;
            next_attempt = 0;
        }

        uint64_t now = montauk::get_milliseconds();
        if (next_attempt != 0 && now < next_attempt) {
            montauk::sleep_ms(CONFIG_POLL_MS);
            continue;
        }

        montauk::abi::NetCfg net = {};
        montauk::get_netcfg(&net);
        if (net.ipAddress == 0 || net.dnsServer == 0) {
            next_attempt = now + RETRY_INTERVAL_MS;
            montauk::sleep_ms(CONFIG_POLL_MS);
            continue;
        }

        int result = montauk::ntp::synchronize(server);
        log(montauk::ntp::result_string(result));
        next_attempt = montauk::get_milliseconds() +
            (result == montauk::ntp::OK ? SYNC_INTERVAL_MS : RETRY_INTERVAL_MS);
        montauk::sleep_ms(CONFIG_POLL_MS);
    }
}