export function parseDateFromFormat(str: string, format: string): Date | null {
    if (!str) return null;
  
    const sepMatch = format.match(/[^A-Z]/i);
    if (!sepMatch) return null;
    const sep = sepMatch[0];
  
    if (!str.includes(sep)) return null;
  
    const parts = str.split(sep);
    const fmtParts = format.split(sep);
  
    let day: number | null = null;
    let month: number | null = null;
    let year: number | null = null;
  
    for (let i = 0; i < fmtParts.length; i++) {
      const f = fmtParts[i];
      const v = parts[i];
      if (!v) return null;
  
      if (f === "DD") {
        if (v.length !== 2) return null;
        day = Number(v);
      }
  
      if (f === "MM") {
        if (v.length !== 2) return null;
        month = Number(v) - 1;
      }
  
      if (f === "YYYY") {
        if (v.length !== 4) return null;
        year = Number(v);
      }
    }
  
    if (day == null || month == null || year == null) return null;
  
    const d = new Date(year, month, day);
    if (
      d.getFullYear() !== year ||
      d.getMonth() !== month ||
      d.getDate() !== day
    ) return null;
  
    return d;
  }

  export function formatDateToFormat(date: Date, format: string): string {
    if (!date) return "";
  
    const day = String(date.getDate()).padStart(2, "0");
    const month = String(date.getMonth() + 1).padStart(2, "0");
    const year = date.getFullYear();
  
    switch (format) {
      case "DD/MM/YYYY":
        return `${day}/${month}/${year}`;
      case "MM/DD/YYYY":
        return `${month}/${day}/${year}`;
      case "YYYY/MM/DD":
        return `${year}/${month}/${day}`;
      case "YYYY.MM.DD":
        return `${year}.${month}.${day}`;
      case "DD.MM.YYYY":
        return `${day}.${month}.${year}`;
      default:
        return `${day}/${month}/${year}`;
    }
  }

  export function parseRangeFromFormat(
    input: string,
    format: string,
    isRange: boolean,
    separator: string
  ) {
    if (!isRange) {
      return { first: parseDateFromFormat(input, format), second: null };
    }
  
    if (!input.includes(separator)) {
      return { first: parseDateFromFormat(input, format), second: null };
    }
  
    const [firstRaw, secondRaw] = input.split(separator);
  
    const first = parseDateFromFormat(firstRaw, format);
    const second = secondRaw ? parseDateFromFormat(secondRaw, format) : null;
  
    return { first, second };
  }
  
  
  export function normalizeDateRange(
    first: Date | null,
    second: Date | null
  ): [Date | null, Date | null] {
    if (first && second && first.getTime() > second.getTime()) {
      return [second, first];
    }
    return [first, second];
  }