Convert external links to other enabled docs to internal links

assets/javascripts/app/app.coffee

@@ -25,6 +25,7 @@
     @shortcuts = new app.Shortcuts
     @document = new app.views.Document
     @mobile = new app.views.Mobile if @isMobile()
+    @urls = new app.Urls
 
     if document.body.hasAttribute('data-doc')
       @DOC = JSON.parse(document.body.getAttribute('data-doc'))
@@ -112,6 +113,7 @@
   initDoc: (doc) ->
     doc.entries.add type.toEntry() for type in doc.types.all()
     @entries.add doc.entries.all()
+    @urls.addDoc doc
     return
 
   migrateDocs: ->

assets/javascripts/app/urls.coffee

@@ -0,0 +1,31 @@
+class app.Urls
+  _map: {}
+  _cached: {}
+
+  get: (url) ->
+    return unless url
+    parsed = new URL(url)
+    @_cached?[parsed.host]?[_keyFor(parsed)]
+
+  addDoc: (doc) ->
+    @_map[doc.slug] = doc.entries
+      .all()
+      .filter (entry) -> entry.url
+      .map (entry) -> [entry.url, entry.path]
+    @rebuild()
+
+  removeDoc: (doc) ->
+    deleted = delete @_map[doc.slug]
+    @rebuild() if deleted
+    delted
+
+  rebuild: ->
+    @_cached = {}
+    for slug, entries of @_map
+      for [url, path] in entries
+        parsed = new URL(url)
+        @_cached[parsed.host] ?= {}
+        @_cached[parsed.host][_keyFor(parsed)] = "/#{slug}/#{path}"
+
+
+_keyFor = (parsed) -> parsed.pathname + parsed.search + parsed.hash

assets/javascripts/models/entry.coffee

@@ -1,7 +1,7 @@
 #= require app/searcher
 
 class app.models.Entry extends app.Model
-  # Attributes: name, type, path
+  # Attributes: name, type, path, url
 
   constructor: ->
     super

assets/javascripts/views/content/entry_page.coffee

@@ -34,7 +34,9 @@ class app.views.EntryPage extends app.View
 
     $.batchUpdate @el, =>
       @subview.render(content, fromCache)
-      @addCopyButtons() unless fromCache
+      unless fromCache
+        @addCopyButtons()
+        @internalizeLinks()
       return
 
     if app.disabledDocs.findBy 'slug', @entry.doc.slug
@@ -55,6 +57,14 @@ class app.views.EntryPage extends app.View
     el.appendChild @copyButton.cloneNode(true) for el in @findAllByTag('pre')
     return
 
+  internalizeLinks: ->
+    for el in @findAllByTag('a')
+      continue if el.classList.contains '_attribution-link'
+
+      internalUrl = app.urls.get(el.href)
+      if internalUrl?
+        el.href = internalUrl
+
   polyfillMathML: ->
     return unless window.supportsMathML is false and !@polyfilledMathML and @findByTag('math')
     @polyfilledMathML = true

lib/docs/core/models/entry.rb

@@ -4,22 +4,24 @@ module Docs
   class Entry
     class Invalid < StandardError; end
 
-    attr_accessor :name, :type, :path
+    attr_accessor :name, :type, :path, :url
 
-    def initialize(name = nil, path = nil, type = nil)
+    def initialize(name = nil, path = nil, type = nil, url = nil)
       self.name = name
       self.path = path
       self.type = type
+      self.url = url
 
       unless root?
         raise Invalid, 'missing name' if !name || name.empty?
         raise Invalid, 'missing path' if !path || path.empty?
         raise Invalid, 'missing type' if !type || type.empty?
+        raise Invalid, 'missing url'  if !url  || url.empty?
       end
     end
 
     def ==(other)
-      other.name == name && other.path == path && other.type == type
+      other.name == name && other.path == path && other.type == type && other.url == url
     end
 
     def name=(value)
@@ -35,7 +37,7 @@ def root?
     end
 
     def as_json
-      { name: name, path: path, type: type }
+      { name: name, path: path, type: type, url: url }
     end
   end
 end

lib/docs/filters/core/entries.rb

@@ -56,8 +56,10 @@ def build_entries(entries)
 
     def build_entry(name, frag = nil, type = nil)
       type ||= self.type
-      path = frag ? (frag.include?('#') ? frag : "#{self.path}##{frag}") : self.path
-      Entry.new(name, path, type)
+      hash_frag = frag ? (frag.include?('#') ? frag : "##{frag}") : ''
+      path = "#{self.path}#{hash_frag}"
+      url = "#{current_url}#{hash_frag}"
+      Entry.new(name, path, type, url)
     end
   end
 end