substring. Codewar kudos task

// 1 цель: надо собрать перебрать подстроки по макс. 
// длине подстроки с неважно каким порядком, главное не алфавитное сортировка 
// а максимально подборка неповторимых букв с возможным повторение друг за другом
const ss1 = 'ab';
const ss2 = 'cba';
const ss3 = 'ccabb';

const temp = 'abccbbacaaaba';

type indexes = {
  [k:string]:number
};

function func(str:string) {
  const uniqueLetters: Set<string> = new Set(str);
  const subCandidates:Array<string> = [];
  const strArr = str.split('');
  const indexes = {};
  const tempo:number[][] = [];
  for (let u of uniqueLetters) {
    tempo.push(strArr.reduce((acc:number[],n,i) => i === 0 ? [0] : (n === u ? [...acc, i] : acc), []))
  
  }
};

function findSubstrings(uniqueLetters: Set<string>, strs: Array<string>) {
  const indexes: Array<string>[] = [];
  let arrangedLetters: string[] = [];


  let count: number = 0;
  let i: number = 0;
  let j: number = 0;
  console.log('before count');

  const compare2Strings = (p: string, n: string): string => {
    let finalString: string = '';
    const pSet = new Set(p);
    const nSet = new Set(n);
    
    if (pSet.size === uniqueLetters.size && nSet.size < uniqueLetters.size) {
      console.log('pSet === uniqueLetters')
      finalString = p;
    } else if (pSet.size < uniqueLetters.size && nSet.size === uniqueLetters.size) {
      console.log('nSet === uniqueLetters')
      finalString = n;
    } else if (pSet.size === uniqueLetters.size && nSet.size === uniqueLetters.size) {
      console.log('pSet === nSet')

      const isStringValid = (pp: string): boolean => {
          const ppArray = pp.split('');
          const ppSet = new Set(ppArray);
          const allLetters:Array<boolean> = [];

          const checkAllLetters = (arr: Array<string>, l: string): boolean => {
            const occurencies: Array<number> = arr.reduce((accum: Array<number>, c: string, ii: number) =>
              ii === 0 ? [0] : ( c === l ? [...accum, ii] : accum), []);//[0,2,3]
            const b: Array<boolean> = occurencies.reduce((accum: Array<boolean>, c: number, ii: number) => {
              return ii === 0 ? [true] : (occurencies[ii] - 1 === occurencies[ii - 1] ? [...accum, true] : [...accum, false])
            }, []);//[true,false,true]
            return b.every(e => !!e);
          }

          for (const l of ppSet) {
            allLetters.push(checkAllLetters(ppArray, l));
          }
          return allLetters.every(e=>!!e)
        };

        
        if (isStringValid(p))
          finalString = p;
        else
          finalString = n;
      
      } else
        finalString = 'no string found';

    return finalString
    }
    const a = strs.reduce(compare2Strings);
    console.log('final string: ' + a)
  };

findSubstrings(temp, [ss1, ss2, ss3]);
console.log('end')