function HashTable(size) {
  this.buckets = Array(size);
  this.numBuckets = this.buckets.length;
}

function HashNode(key, value, next) {
  this.key = key;
  this.value = value;
  this.next = next || null
}

HashTable.prototype.hash = function(key) {
    var total = 0;
    for (var i = 0; i < key.length; i++) {
        total += key.charCodeAt(i);
    }
    var bucket = total % this.numBuckets;
    return bucket;
};


HashTable.prototype.insert = function(key, value) {
    var index = this.hash(key);
   // console.log('INDEX', index);
    if (!this.buckets[index]) {
      this.buckets[index] = new HashNode(key, value);
    }
    else if (this.buckets[index].key === key) {
      this.buckets[index].value = value;
    }
    else {
      var currentNode = this.buckets[index];
      while (currentNode.next) {
        if(currentNode.next.key === key) {
          currentNode.next.value = value;
          return;
        }
          currentNode = currentNode.next;
      }
      currentNode.next = new HashNode(key, value);
    }
}



HashTable.prototype.get = function(key) {
  var index = this.hash(key);
  if (!this.buckets[index]) return null;
  else {
    var currentNode = this.buckets[index];
    while (currentNode) {
      if (currentNode.key === key) return currentNode.value;
      currentNode = currentNode.next;
    }
    return null;
  }
};


HashTable.prototype.retrieveAll = function() {
  var allNodes = [];
  for (var i = 0; i < this.numBuckets; i++) {
      var currentNode = this.buckets[i];
      while(currentNode) {
          allNodes.push(currentNode)
          currentNode = currentNode.next;
      }
  }
  return allNodes;
}



var myHT = new HashTable(30);
//myHT.hash('Becca')
//console.log(myHT);


myHT.insert('Dean', 'dean@gmail.com');
myHT.insert('Megan', 'megan@gmail.com');
myHT.insert('Dane', 'dane@yahoo.com');
myHT.insert('Dean','deanmachine@gmail.com');
myHT.insert('Megan', 'megansmith@gmail.com');
myHT.insert('Dane', 'dane1010@outlook.com');
myHT.insert('Joe', 'joey@facebook.com');
myHT.insert('Samantha', 'sammy@twitter.com')

console.log(myHT.retrieveAll())

//console.log(myHT.buckets)

console.log(myHT.get('Dane'))


//HASH TABLE have O(1) insertion and lookup