3BCZHcmg

1const gameDetector = (gamesHash, commentsArray) => {
2	//Create a lookup table from the input hash.
3	let unsorted = createLookup(gamesHash);
4
5	//After creating the lookup table, sort it in descending order to tag larger words over smaller words.
6	let sorted = sortObject(unsorted);
7
8	//Concat the comments into one big string to reduce the runtime complexity.
9	let comments = commentsArray.join('#####');
10
11	//Iterating through each lookup value.
12	for (let index in sorted) {
13		//JSLint does not like iteration through an object.
14		if (sorted.hasOwnProperty(index)) {
15			//Find whether the lookup word exists in the comment.
16			let position = comments.indexOf(index);
17
18			//Define empty comments to store new comments if the lookup word exists.
19			let taggedComments = '';
20
21			//Check to see if the word has been tagged already.
22			let tagCheck = comments.slice(position - 4, position);
23
24			//If the word exists and it hasn't been tagged yet, create new comments.
25			if (position !== -1 && tagCheck !== 'TAG{') {
26				//Create a new anagram with the tag.
27				let tagged = `TAG{${sorted[index]},${index}}`;
28
29				/*
30            Find the word in the comments and replace it with tagged string.  The replace function
31            does not mutate the existing comments, so the new comments must be stored in a new variable.
32        */
33				taggedComments = comments.replace(index, tagged);
34			}
35
36			/*
37          Since the tagged comments starts out as a falsy value, the comments will remain
38					the same if nothing is replaced.  Otherwise, if the comments were tagged,
39					the statement will short-circuit and set the comments variable as the new, tagged comments.
40        */
41			comments = taggedComments || comments;
42		}
43	}
44
45	//Return the tagged comments array (or the original array if nothing was changed/found).
46	return comments.split('#####');
47};
48
49//Helper method for creating an inverted lookup table from the input hash.
50const createLookup = gamesHash => {
51	//Define an empty lookup table.
52	let lookup = {};
53
54	//Iterate through the hash input.
55	for (let key in gamesHash) {
56		if (gamesHash.hasOwnProperty(key)) {
57			//Retrieve the value from the hash which should be an array.
58			let value = gamesHash[key];
59
60			//Iterate through that values array and set the lookup table key as the value and vice-versa.
61			for (let j = 0; j < value.length; j++) {
62				lookup[value[j]] = key;
63			}
64		}
65	}
66
67	//Return the lookup table.
68	return lookup;
69};
70
71//Helper method for sorting an object.
72const sortObject = object => {
73	//Make an array for sorting purposes since we cannot sort an object normally.
74	let list = [];
75
76	//Iterate through the object and push in arrays of the key-value pairs.
77	for (let key in object) {
78		if (object.hasOwnProperty(key)) {
79			list.push([key, object[key]]);
80		}
81	}
82
83	//Sort the list in descending order by length of the key.
84	list.sort(function(a, b) {
85		return b[0].length - a[0].length;
86	});
87
88	//Define a new lookup table that is in sorted order.
89	let ordered = {};
90
91	//Iterate through the array.
92	for (let i = 0; i < list.length; i++) {
93		let key = list[i][0];
94		let value = list[i][1];
95
96		//Set key-value pairs for the new lookup table.
97		ordered[key] = value;
98	}
99
100	//Return the lookup table sorted.
101	return ordered;
102};