import { extendedTypeof, isNullUndefined } from ".";
const defaultChars =
  "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_";
let chars = defaultChars;
let usedIDs = [];
let patternIDs = [];

export function createID(
  length?: number,
  preventDuplicates?: boolean,
  byPattern?: boolean,
  patternID_?: number[],
  chars_?: string,
  usedIDs_?: string[]
) {
  let preventDuplicates_ = !isNullUndefined(preventDuplicates)
    ? preventDuplicates
    : true;

  let byPattern_ = !isNullUndefined(byPattern) ? byPattern : false;
  patternIDs = extendedTypeof(patternID_) === "array" ? patternID_ : patternIDs;
  chars = extendedTypeof(chars_) === "string" ? chars_ : defaultChars;
  usedIDs = extendedTypeof(usedIDs_) === "array" ? usedIDs_ : usedIDs;

  let length_ = length ?? 5;
  let r = "";

  function actualCreateID() {
    if ((usedIDs?.length ?? 0) > (chars.length ^ length_)) length_++;

    let r2 = "";
    for (let i = 0; i < length_; i++) {
      r2 += chars.charAt(Math.floor(Math.random() * chars.length));
    }

    if (extendedTypeof(usedIDs) !== "array") usedIDs = [];
    if (preventDuplicates_ && usedIDs?.includes(r2)) return actualCreateID();
    if (!usedIDs?.includes(r2)) usedIDs?.push(r2);
    r = r2;
  }

  function getCharByNum(n: number) {
    return chars[n];
  }

  function actualCreatePatternID() {
    if (patternIDs.length === 0) patternIDs = [...Array(length_)].map((a) => 0);

    if (patternIDs.at(-1) >= chars.length) {
      patternIDs[patternIDs.length - 1] = chars.length - 1;
      let foundInPrevious;
      for (let i = patternIDs.length; i > 0; i--) {
        if (patternIDs[i] < chars.length - 1) {
          foundInPrevious = i;
          patternIDs[i]++;
          patternIDs
            .map((a, i2) => [a, i2])
            .slice(i + 1)
            .forEach((a) => (patternIDs[a[1]] = 0));
          break;
        }
      }

      if (!foundInPrevious) {
        patternIDs.push(0);
        patternIDs.forEach((a, i) => (patternIDs[i] = 0));
      }
    }

    patternIDs.forEach((a) => (r += getCharByNum(a)));
    patternIDs[patternIDs.length - 1]++;
  }

  if (!byPattern_) actualCreateID();
  else actualCreatePatternID();

  return r;
}

Object.defineProperties(createID, {
  patternIDs: {
    get() {
      return patternIDs;
    },
  },
  usedIDs: {
    get() {
      return usedIDs;
    },
  },
  chars: {
    get() {
      return chars;
    },
  },
});