autocomplete-me/index.js at master · CamBuscher/autocomplete-me · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
class Node {
  constructor(value = null) {
    this.value = value;
    this.children = {};
    this.completeWord = {
      timesChosen: 0,
      word: null
    };
  }
}

class Trie {
  constructor() {
    this.root = new Node();
    this.count = 0;
    this.suggestions = [];
  }

  insert(word, node = this.root, arr = []) {
    word = word.toLowerCase();
    const newArr = arr;
    if (node.children[word[0]] && word.length === 1) {
      if (node.children[word[0]].completeWord.word === null) {
        newArr.push(word[0]);
        node.children[word[0]].completeWord.word = newArr.join('');
        this.count++;

      } else {
        return 'That word already exists'
      }

    } else if (node.children[word[0]]) {
      newArr.push(word[0]);
      this.insert(word.slice(1), node.children[word[0]], newArr);

    } else {
      node.children[word[0]] = new Node(word[0]);

      if (word.length === 1 && node.children[word[0]].completeWord.word === null) {
        newArr.push(word[0]);
        node.children[word[0]].completeWord.word = newArr.join('');
        this.count++;

      } else {
        newArr.push(word[0]);
        this.insert(word.slice(1), node.children[word[0]], newArr);
      }
    }
  }

  populate(arr) {
    arr.forEach(el => {
      this.insert(el);
    });
  }

  suggest(str) {
    this.suggestions = [];
    const splitStr = [...str.toLowerCase()];
    let currentNode = this.root;
    for (let i = 0; i < splitStr.length; i++) {
      if (currentNode === undefined) {
        return this.suggestions;
      }
      currentNode = currentNode.children[splitStr[i]];
    }

    this.findTheWords(currentNode);
    this.suggestions.sort((a, b) => b.timesChosen - a.timesChosen);

    this.suggestions = this.suggestions.map(({ word }) => word);
    return this.suggestions;
  }

  findTheWords(currentNode) {
    if (currentNode === undefined || currentNode.children === undefined) {
      return ''
    }

    const childrenKeys = Object.keys(currentNode.children);

    childrenKeys.forEach(key => {
      if (currentNode.children[key].completeWord.word) {
        this.suggestions.push(currentNode.children[key].completeWord);
      }
      this.findTheWords(currentNode.children[key]);
    });
  }

  delete(str) {
    let splitStr = [...str.toLowerCase()];
    let currentNode = this.root;
    for (let i = 0; i < splitStr.length; i++) {
      if (currentNode === undefined) {
        return 'That\'s not a word.';
      }
      currentNode = currentNode.children[splitStr[i]];
    }
    if (currentNode.completeWord.word) {
      currentNode.completeWord.word = null;
      this.count--;
    } else {
      return 'That\'s not a word.';
    }
  }

  select(word) {
    let splitStr = [...word.toLowerCase()];
    let currentNode = this.root;
    for (let i = 0; i < splitStr.length; i++) {
      currentNode = currentNode.children[splitStr[i]];
    }
    currentNode.completeWord.timesChosen++;
  }
}

module.exports = Trie;