trying out the Dictionary and isInDict() function from youtube video

index.js

const Mocha = require('mocha');
const assert = require('assert');
const mocha = new Mocha();

// Bit of a hack, sorry!
mocha.suite.emit('pre-require', this, 'solution', mocha);
/*

from: https://www.youtube.com/watch?v=yju4zwKSriI

Input (array of words):
"cat, "car", "bar"

// do as much work as possible in the setup
// function to optimize the isInDict func
function setup(input)

// optimal is likely O(n) time
// but maybe could be constant time of O(1)
// if you have 1 input like "cat" and it does
// one operation to find it
function isInDict(word)

setup(["cat, "car", "bar"])

isInDict("cat") // true
isInDict("bat") // false


*/

const sampleWords = ["cat", "car", "bar"];
const enUSAlpha = (() => {
  const caps = [...Array(26)].map((val, i) => String.fromCharCode(i + 65));
  return caps.map(letter => letter.toLowerCase());
})();
const dictionary = {};

// this could be closer to O(n * k)
const setup = (words) => {
  words.forEach(word => {
    const chars = word.split("");
    let lastDictionaryLevel = dictionary;
    chars.forEach((char, i) => {
      if (!lastDictionaryLevel[chars[i]] && !chars[i + 1]) {
        lastDictionaryLevel[chars[i]] = word;
      } else if (!lastDictionaryLevel[chars[i]]) {
        lastDictionaryLevel[chars[i]] = {};
      }
      lastDictionaryLevel = lastDictionaryLevel[chars[i]];
    });
  });
  console.log("dictionary", dictionary)
};

const isInDict = (word) => {
  let currentDictLevelFound = dictionary;
  let possibleCurrentDictLevels = dictionary;
  let wordFound = false;
  let possibleCurrentDictLevel = null;
  for (let i = 0; i < word.length; i++) {
    const char = word[i];
    
    if (char === "*") {
      possibleCurrentDictLevels = enUSAlpha.map(char => currentDictLevelFound && currentDictLevelFound[char]).filter(entry => !!entry);
      
      if (!possibleCurrentDictLevels || possibleCurrentDictLevels.length === 0) break;
      
      // possibleCurrentDictLevel = null;
      
      console.log("possibleCurrentDictLevels",possibleCurrentDictLevels)
      for (let j = 0; j <= possibleCurrentDictLevels.length; j++) {
        possibleCurrentDictLevel = possibleCurrentDictLevels[j];
        console.log('possibleCurrentDictLevel',possibleCurrentDictLevel)
        if (possibleCurrentDictLevel && typeof possibleCurrentDictLevel === "string") {
          wordFound = true;
        }
      }
    } else {
      currentDictLevelFound = currentDictLevelFound[char];
      if (typeof currentDictLevelFound === "string") {
        wordFound = true;
      }
    }
    

  }
  
  /* 
  if char === "*" 
  
  then search all 26 letters as char
  */
  console.log("wordFound", wordFound)
  return wordFound;
}


// "cat, "car", "bar"
// setup();


describe('Test suite', function() {
  setup(sampleWords);
  describe('when word in dict', function() {
    it("it returns true", () => {
      assert.equal(isInDict("cat"), true)
    })
  })
  describe('when word is NOT in dict', function() {
    it("it returns false", () => {
      assert.equal(isInDict("bat"), false)
    })
  })
  describe('when word WITH WILDCARD is in dict', function() {
    it("it returns TRUE", () => {
      assert.equal(isInDict("*at"), true)
    })
  })
  describe('when word WITH WILDCARD is NOT in dict', function() {
    it("it returns TRUE", () => {
      assert.equal(isInDict("cr*"), false)
    })
  })
})

mocha.run()