#include "timezone_helper.h"
#include <gtest/gtest.h>
#include <ctime>

using namespace radiantwave::timezone;

TEST(TimeZoneTest, GetStandardTimeZonesNonEmpty) {
    const auto& countries = getStandardTimeZones();
    EXPECT_FALSE(countries.empty());

    bool found_us = false;
    bool found_utc = false;

    for (const auto& c : countries) {
        if (c.country_name == "United States") found_us = true;
        if (c.country_name == "Coordinated Universal Time") found_utc = true;
    }

    EXPECT_TRUE(found_us);
    EXPECT_TRUE(found_utc);
}

TEST(TimeZoneTest, UtcTimestampFormat) {
    std::string iso = getUtcTimestampIso();
    EXPECT_FALSE(iso.empty());
    EXPECT_NE(iso.find("UTC"), std::string::npos);
}

TEST(TimeZoneTest, CurrentLocalMinutesInRangeAndMatchesUtc) {
    int minutes = currentLocalMinutes("UTC");
    EXPECT_GE(minutes, 0);
    EXPECT_LT(minutes, 1440);

    // Cross-check against the UTC wall clock. The two calls happen within the
    // same second, so a minute-boundary rollover is vanishingly unlikely.
    time_t now = std::time(nullptr);
    struct tm gmt_buf;
    gmtime_r(&now, &gmt_buf);
    EXPECT_EQ(minutes, gmt_buf.tm_hour * 60 + gmt_buf.tm_min);

    // A timezone that is known to differ from UTC must still be in range.
    int ny = currentLocalMinutes("America/New_York");
    EXPECT_GE(ny, 0);
    EXPECT_LT(ny, 1440);
}

TEST(TimeZoneTest, FormatUtcToTimezone) {
    // 2026-07-24 12:00:00 UTC
    // Fixed epoch timestamp: 1784808000
    time_t fixed_utc = 1784808000;

    std::string formatted_ny = formatUtcToTimezone(fixed_utc, "America/New_York", "%Y-%m-%d %H:%M:%S");
    std::string formatted_utc = formatUtcToTimezone(fixed_utc, "UTC", "%Y-%m-%d %H:%M:%S");

    EXPECT_FALSE(formatted_ny.empty());
    EXPECT_EQ(formatted_utc, "2026-07-23 12:00:00");
}