export class TimeSpan {
	private start: { hours: number; minutes: number };
	private end: { hours: number; minutes: number };
	private timeZone;

	constructor(timeSpanStr: string, timeZone: string) {
		const [startStr, endStr] = timeSpanStr.split("-");
		this.start = this.parseTime(startStr);
		this.end = this.parseTime(endStr);
		this.timeZone = timeZone;
	}

	private parseTime(timeStr: string) {
		const [hours, minutes] = timeStr.split(":").map(Number);
		return { hours, minutes };
	}

	contains(timestamp: number = Date.now()): boolean {
		const date = new Date(timestamp);

		const berlinTimeStr = date.toLocaleString("de-DE", {
			timeZone: this.timeZone, // "Europe/Berlin"
			hour12: false,
			hour: "2-digit",
			minute: "2-digit",
		});

		const [hours, minutes] = berlinTimeStr.split(":").map(Number);
		const currentMinutes = hours * 60 + minutes;
		const startMinutes = this.start.hours * 60 + this.start.minutes;
		const endMinutes = this.end.hours * 60 + this.end.minutes;

		if (startMinutes > endMinutes) {
			return currentMinutes >= startMinutes || currentMinutes < endMinutes;
		} else {
			return currentMinutes >= startMinutes && currentMinutes < endMinutes;
		}
	}
}

export interface TimeBetween {
	seconds: number;
	toReadable: (roundToMinutes?: boolean) => string;
}

export function calculateSecondsBetween(
	start: number,
	end: number,
): TimeBetween {
	const seconds = Math.max(60, (end - start) / 1000);
	return {
		seconds,
		toReadable: (roundToMinutes?: boolean) =>
			formatSecondsToDHMS(seconds, roundToMinutes),
	};
}

export function formatSecondsToDHMS(
	secs: number,
	roundToMinutes: boolean = false,
): string {
	const totalSeconds = roundToMinutes ? Math.round(secs / 60) * 60 : secs;

	const days = Math.floor(totalSeconds / (3600 * 24));
	const hours = Math.floor((totalSeconds % (3600 * 24)) / 3600);
	const minutes = Math.floor((totalSeconds % 3600) / 60);
	const seconds = Math.floor(totalSeconds % 60);

	const dayDisplay = days > 0 ? days + (days === 1 ? " day, " : " days, ") : "";
	const hourDisplay =
		hours > 0 ? hours + (hours === 1 ? " hour, " : " hours, ") : "";
	const minuteDisplay =
		minutes > 0 ? minutes + (minutes === 1 ? " minute, " : " minutes, ") : "";
	const secondDisplay =
		seconds > 0 ? seconds + (seconds === 1 ? " second" : " seconds") : "";
	return (dayDisplay + hourDisplay + minuteDisplay + secondDisplay).replace(
		/,\s*$/,
		"",
	);
}

export function formatSecondsToMS(s: number): string {
	const mins = Math.floor(s / 60);
	const secs = s % 60;
	return `${mins}:${secs < 10 ? "0" : ""}${secs}`;
}