BgUtils; move tabRecency to bg_tiles.coffee.

Certain background-page utilities are actually shared, and are therefore
best placed in place that reflects that.

Here, tabRecency is moved to the new gb_utils.coffee in preparation for
implementing a go-to-previous-tab command.  In particular, it is no
longer appropriate that tabRecency be embedded within the completion
code.

logMessage() from main.coffee is also a candidate for moving to
bg_utils.coffee.

1 files changed, 1 insertions, 43 deletions

diff --git a/background_scripts/completion.coffee b/background_scripts/completion.coffee
index 2427bad8..c880a26c 100644
--- a/background_scripts/completion.coffee
+++ b/background_scripts/completion.coffee
@@ -351,47 +351,6 @@ class DomainCompleter
   parseDomainAndScheme: (url) ->
       Utils.hasFullUrlPrefix(url) and not Utils.hasChromePrefix(url) and url.split("/",3).join "/"
 
-# TabRecency associates a logical timestamp with each tab id.  These are used to provide an initial
-# recency-based ordering in the tabs vomnibar (which allows jumping quickly between recently-visited tabs).
-class TabRecency
-  timestamp: 1
-  current: -1
-  cache: {}
-  lastVisited: null
-  lastVisitedTime: null
-  timeDelta: 500 # Milliseconds.
-
-  constructor: ->
-    chrome.tabs.onActivated.addListener (activeInfo) => @register activeInfo.tabId
-    chrome.tabs.onRemoved.addListener (tabId) => @deregister tabId
-
-    chrome.tabs.onReplaced.addListener (addedTabId, removedTabId) =>
-      @deregister removedTabId
-      @register addedTabId
-
-  register: (tabId) ->
-    currentTime = new Date()
-    # Register tabId if it has been visited for at least @timeDelta ms.  Tabs which are visited only for a
-    # very-short time (e.g. those passed through with `5J`) aren't registered as visited at all.
-    if @lastVisitedTime? and @timeDelta <= currentTime - @lastVisitedTime
-      @cache[@lastVisited] = ++@timestamp
-
-    @current = @lastVisited = tabId
-    @lastVisitedTime = currentTime
-
-  deregister: (tabId) ->
-    if tabId == @lastVisited
-      # Ensure we don't register this tab, since it's going away.
-      @lastVisited = @lastVisitedTime = null
-    delete @cache[tabId]
-
-  # Recently-visited tabs get a higher score (except the current tab, which gets a low score).
-  recencyScore: (tabId) ->
-    @cache[tabId] ||= 1
-    if tabId == @current then 0.0 else @cache[tabId] / @timestamp
-
-tabRecency = new TabRecency()
-
 # Searches through all open tabs, matching on title and URL.
 class TabCompleter
   filter: ({ queryTerms }, onComplete) ->
@@ -414,7 +373,7 @@ class TabCompleter
     if suggestion.queryTerms.length
       RankingUtils.wordRelevancy(suggestion.queryTerms, suggestion.url, suggestion.title)
     else
-      tabRecency.recencyScore(suggestion.tabId)
+      BgUtils.tabRecency.recencyScore(suggestion.tabId)
 
 class SearchEngineCompleter
   @debug: false
@@ -862,4 +821,3 @@ root.SearchEngineCompleter = SearchEngineCompleter
 root.HistoryCache = HistoryCache
 root.RankingUtils = RankingUtils
 root.RegexpCache = RegexpCache
-root.TabRecency = TabRecency