#include "clock_model.h"

#include <cstdio>
#include <cstdlib>
#include <ctime>

namespace roro {

bool ClockModel::set(int64_t utcSeconds, TimeSource source, uint32_t nowMs) {
    if (source < source_) return false;
    source_ = source;
    utcAtSet_ = utcSeconds;
    msAtSet_ = nowMs;
    return true;
}

int64_t ClockModel::utcNow(uint32_t nowMs) const {
    // Unsigned subtraction handles the millis() wraparound. Uptime beyond 49 days between two
    // sets would lose 49 days; sources refresh far more often than that.
    return utcAtSet_ + static_cast<int64_t>(static_cast<uint32_t>(nowMs - msAtSet_) / 1000);
}

void ClockModel::applyTimezone(const char* posixTz) {
    setenv("TZ", posixTz, 1);
    tzset();
}

std::string ClockModel::formatLocalTime(int64_t utcSeconds) {
    time_t t = static_cast<time_t>(utcSeconds);
    struct tm local;
    localtime_r(&t, &local);
    char buf[8];
    std::snprintf(buf, sizeof(buf), "%02d:%02d", local.tm_hour, local.tm_min);
    return buf;
}

std::string ClockModel::formatLocalDate(int64_t utcSeconds) {
    time_t t = static_cast<time_t>(utcSeconds);
    struct tm local;
    localtime_r(&t, &local);
    char buf[12];
    std::snprintf(buf, sizeof(buf), "%04d-%02d-%02d", local.tm_year + 1900, local.tm_mon + 1, local.tm_mday);
    return buf;
}

std::string ClockModel::formatAge(int64_t seconds) {
    char buf[24];
    if (seconds < 60) return "now";
    if (seconds < 3600)
        std::snprintf(buf, sizeof(buf), "%d min ago", static_cast<int>(seconds / 60));
    else if (seconds < 86400)
        std::snprintf(buf, sizeof(buf), "%d h ago", static_cast<int>(seconds / 3600));
    else
        std::snprintf(buf, sizeof(buf), "%d d ago", static_cast<int>(seconds / 86400));
    return buf;
}

}  // namespace roro