// $$$$ Map $$$$ ///

const mapObj1 = new Map([
  ["a", 1],
  ["b", 2],
  ["c", 3],
  ["d", 4]
]);

const obj1 = {
  a: 1,
  b: 2,
  c: 3,
  d: 4
}

console.log(obj1.constructor) // and many more

// better preformance then plain object
mapObj1.delete('a')
mapObj1.set('a', 1)

console.log(obj1, mapObj1);


// loop through maps

for ([key, val] of mapObj1) {
  console.log(key ,val)
} 


//  Map is indexed
const itemThree = [...mapObj1][3];
console.log(itemThree);

// convert map <=> ojb
const mapObj3ToObj = Object.fromEntries(mapObj1);
console.log(mapObj3ToObj);

const objToMap = new Map(Object.entries(mapObj3ToObj));
console.log(mapObj3ToObj, objToMap);


// clone/copy map

const mapObj2 = new Map(mapObj1);
const mapObj3 = structuredClone(mapObj1);

console.log('clone:',mapObj2);
console.log('deep clone:',mapObj3);

// map specialist

mapObj1.set(['e','f'], true);
mapObj1.set(mapObj3ToObj, {a:1});
// *** can be a problem with garbage collector better to use WeakMap

console.log(mapObj1.size);

console.log(mapObj1)

// stringify Map

const originalValue = new Map([['a', 1]]);
const str = JSON.stringify(originalValue, replacer);
console.log(str);
function replacer(key, value) {
  if(value instanceof Map) {
    return {
      dataType: 'Map',
      value: Array.from(value.entries())
    };
  } else {
    return value;
  }
}

// $$$$ Set $$$$ ///

const objA = {a:1};
const a = new Set([1, 2, 3]);
const b = new Set([2, objA, 4 , objA, {a:2}]);

a.has(1);
a.add('3');
a.delete(3);

console.log(console.timeStamp());
console.timeStamp()









// const b = new Map([
//   [1, "one"],
//   [2, "two"],
//   [4, "four"],
// ]);
// console.log(a); // Set(4) {1, 2, 3, 4}

// console.log(mapObj1.get('e'), obj1.e);