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
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
class Suggestion
showRelevancy: true # Set this to true to render relevancy when debugging the ranking scores.
# - type: one of [bookmark, history, tab].
constructor: (@queryTerms, @type, @url, @title, @computeRelevancyFunction, @extraRelevancyData) ->
generateHtml: ->
return @html if @html
relevancyHtml = if @showRelevancy then "<span class='relevancy'>#{@computeRelevancy() + ''}</span>" else ""
@html =
"<div class='topHalf'>
<span class='source'>#{@type}</span>
<span class='title'>#{@highlightTerms(utils.escapeHtml(@title))}</span>
</div>
<div class='bottomHalf'>
<span class='url'>#{@shortenUrl(@highlightTerms(@url))}</span>
#{relevancyHtml}
</div>"
shortenUrl: (url) ->
@stripTrailingSlash(url).replace(/^http:\/\//, "")
stripTrailingSlash: (url) ->
url = url.substring(url, url.length - 1) if url[url.length - 1] == "/"
url
# Wraps each occurence of the query terms in the given string in a <span>.
highlightTerms: (string) ->
toReplace = {}
for term in @queryTerms
regexp = @escapeRegexp(term)
i = string.search(regexp)
toReplace[i] = term.length if i >= 0 && (!toReplace[i] || toReplace[i].length < term.length)
indices = []
indices.push([key, toReplace[key]]) for key of toReplace
indices.sort (a, b) -> b - a
for [i, length] in indices
i = +i # convert i from String to Integer.
string =
string.substr(0, i) +
"<span class='match'>" + string.substr(i, length) + "</span>" +
string.substr(i + length)
string
# Creates a Regexp from the given string, with all special Regexp characters escaped.
escapeRegexp: (string) ->
# Taken from http://stackoverflow.com/questions/3446170/escape-string-for-use-in-javascript-regex
Suggestion.escapeRegExp ||= /[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g
new RegExp(string.replace(Suggestion.escapeRegExp, "\\$&"), "i")
computeRelevancy: -> @relevancy = @computeRelevancyFunction(@queryTerms, this)
class BookmarkCompleter
currentSearch: null
# These bookmarks are loaded asynchronously when refresh() is called.
bookmarks: null
filter: (@queryTerms, @onComplete) ->
@currentSearch = { queryTerms: @queryTerms, onComplete: @onComplete }
@performSearch() if @bookmarks
onBookmarksLoaded: -> @performSearch() if @currentSearch
performSearch: ->
results = @bookmarks.filter (bookmark) =>
RankingUtils.matches(@currentSearch.queryTerms, bookmark.url, bookmark.title)
suggestions = results.map (bookmark) =>
new Suggestion(@currentSearch.queryTerms, "bookmark", bookmark.url, bookmark.title, @computeRelevancy)
onComplete = @currentSearch.onComplete
@currentSearch = null
onComplete(suggestions)
refresh: ->
@bookmarks = null
chrome.bookmarks.getTree (bookmarks) =>
@bookmarks = @traverseBookmarks(bookmarks).filter((bookmark) -> bookmark.url?)
@onBookmarksLoaded()
# Traverses the bookmark hierarchy, and retuns a flattened list of all bookmarks in the tree.
traverseBookmarks: (bookmarks) ->
results = []
toVisit = bookmarks
while toVisit.length > 0
bookmark = toVisit.shift()
results.push(bookmark)
toVisit.push.apply(toVisit, bookmark.children) if (bookmark.children)
results
computeRelevancy: (queryTerms, suggestion) ->
RankingUtils.wordRelevancy(queryTerms, suggestion.url, suggestion.title)
class HistoryCompleter
filter: (queryTerms, onComplete) ->
@currentSearch = { queryTerms: @queryTerms, onComplete: @onComplete }
results = []
HistoryCache.use (history) ->
results = history.filter (entry) -> RankingUtils.matches(queryTerms, entry.url, entry.title)
suggestions = results.map (entry) =>
new Suggestion(queryTerms, "history", entry.url, entry.title, @computeRelevancy, entry)
onComplete(suggestions)
computeRelevancy: (queryTerms, suggestion) ->
@oneMonthAgo ||= 1000 * 60 * 60 * 24 * 30
historyEntry = suggestion.extraRelevancyData
recency = Date.now() - historyEntry.lastVisitTime
recencyDifference = Math.max(0, @oneMonthAgo - recency) / @oneMonthAgo
# recencyScore is between [0, 1]. It is 1 when recenyDifference is 0. This qudratic equation will
# incresingly discount older history entries.
recencyScore = recencyDifference * recencyDifference * recencyDifference
wordRelevancy = RankingUtils.wordRelevancy(queryTerms, suggestion.url, suggestion.title)
# Average out the word score and the recency. Recency has the ability to pull the score up, but not down.
score = (wordRelevancy + Math.max(recencyScore, wordRelevancy)) / 2
refresh: ->
class MultiCompleter
constructor: (@completers) ->
@maxResults = 10 # TODO(philc): Should this be configurable?
refresh: -> completer.refresh() for completer in @completers
filter: (queryTerms, onComplete) ->
suggestions = []
completersFinished = 0
for completer in @completers
# Call filter() on every source completer and wait for them all to finish before returning results.
completer.filter queryTerms, (newSuggestions) =>
suggestions = suggestions.concat(newSuggestions)
completersFinished += 1
if completersFinished >= @completers.length
results = @sortSuggestions(suggestions)[0...@maxResults]
result.generateHtml() for result in results
onComplete(results)
sortSuggestions: (suggestions) ->
for suggestion in suggestions
suggestion.computeRelevancy(@queryTerms)
suggestions.sort (a, b) -> b.relevancy - a.relevancy
suggestions
RankingUtils =
# Whether the given URL or title match any one of the query terms. This is used to prune out irrelevant
# suggestions before we try to rank them.
matches: (queryTerms, url, title) ->
return false if queryTerms.length == 0
for term in queryTerms
return false unless title.indexOf(term) >= 0 || url.indexOf(term) >= 0
true
# Returns a number between [0, 1] indicating how often the query terms appear in the url and title.
wordRelevancy: (queryTerms, url, title) ->
queryLength = 0
urlScore = 0.0
titleScore = 0.0
for term in queryTerms
queryLength += term.length
urlScore += 1 if url.indexOf(term) >= 0
titleScore += 1 if title.indexOf(term) >= 0
urlScore = urlScore / queryTerms.length
urlScore = urlScore * RankingUtils.normalizeDifference(queryLength, url.length)
titleScore = titleScore / queryTerms.length
titleScore = titleScore * RankingUtils.normalizeDifference(queryLength, title.length)
(urlScore + titleScore) / 2
# Takes the difference of two numbers and returns a number between [0, 1] (the percentage difference).
normalizeDifference: (a, b) ->
max = Math.max(a, b)
(max - Math.abs(a - b)) / max
# Provides cached access to Chrome's history.
HistoryCache =
size: 20000
history: null # An array of History items returned from Chrome.
use: (callback) ->
return @fetchHistory(callback) unless @history?
callback(@history)
fetchHistory: (callback) ->
return @callbacks.push(callback) if @callbacks
@callbacks = [callback]
chrome.history.search { text: "", maxResults: @size, startTime: 0 }, (history) =>
# sorting in ascending order. We will push new items on to the end as the user navigates to new pages.
history.sort((a, b) -> (a.lastVisitTime || 0) - (b.lastVisitTime || 0))
@history = history
chrome.history.onVisited.addListener (newSite) =>
firstTimeVisit = (newSite.visitedCount == 1)
@history.push(newSite) if firstTimeVisit
callback(@history) for callback in @callbacks
@callbacks = null
root = exports ? window
root.Suggestion = Suggestion
root.BookmarkCompleter = BookmarkCompleter
root.MultiCompleter = MultiCompleter
root.HistoryCompleter = HistoryCompleter
|
