/*
 * Copyright (C) 2026 Fluxer Contributors
 *
 * This file is part of Fluxer.
 *
 * Fluxer is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Fluxer 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with Fluxer. If not, see <https://www.gnu.org/licenses/>.
 */

import type {I18n} from '@lingui/core';
import {msg} from '@lingui/core/macro';

export const formatRegion = (i18n: I18n, countryCode: string | null, regionCode: string | null): string => {
	if (!countryCode) {
		return i18n._(msg`your region`);
	}

	try {
		const countryName = new Intl.DisplayNames(['en'], {type: 'region'}).of(countryCode);

		if (countryCode === 'US' && regionCode) {
			try {
				const stateName = getUSStateName(regionCode);
				return `${stateName}, ${countryName || 'United States'}`;
			} catch {
				return countryName || countryCode;
			}
		}

		return countryName || countryCode;
	} catch {
		return countryCode;
	}
};

const getUSStateName = (stateCode: string): string => {
	const states: Record<string, string> = {
		AL: 'Alabama',
		AK: 'Alaska',
		AZ: 'Arizona',
		AR: 'Arkansas',
		CA: 'California',
		CO: 'Colorado',
		CT: 'Connecticut',
		DE: 'Delaware',
		FL: 'Florida',
		GA: 'Georgia',
		HI: 'Hawaii',
		ID: 'Idaho',
		IL: 'Illinois',
		IN: 'Indiana',
		IA: 'Iowa',
		KS: 'Kansas',
		KY: 'Kentucky',
		LA: 'Louisiana',
		ME: 'Maine',
		MD: 'Maryland',
		MA: 'Massachusetts',
		MI: 'Michigan',
		MN: 'Minnesota',
		MS: 'Mississippi',
		MO: 'Missouri',
		MT: 'Montana',
		NE: 'Nebraska',
		NV: 'Nevada',
		NH: 'New Hampshire',
		NJ: 'New Jersey',
		NM: 'New Mexico',
		NY: 'New York',
		NC: 'North Carolina',
		ND: 'North Dakota',
		OH: 'Ohio',
		OK: 'Oklahoma',
		OR: 'Oregon',
		PA: 'Pennsylvania',
		RI: 'Rhode Island',
		SC: 'South Carolina',
		SD: 'South Dakota',
		TN: 'Tennessee',
		TX: 'Texas',
		UT: 'Utah',
		VT: 'Vermont',
		VA: 'Virginia',
		WA: 'Washington',
		WV: 'West Virginia',
		WI: 'Wisconsin',
		WY: 'Wyoming',
		DC: 'District of Columbia',
	};

	return states[stateCode] || stateCode;
};