support for twitter downloads

app/logical/downloads/rewrite_strategies/base.rb

@@ -6,7 +6,7 @@ module Downloads
       end
 
       def self.strategies
-        [Pixiv, NicoSeiga, Twitpic, DeviantArt, Tumblr, Moebooru]
+        [Pixiv, NicoSeiga, Twitpic, DeviantArt, Tumblr, Moebooru, Twitter]
       end
 
       def rewrite(url, headers, data = {})

app/logical/downloads/rewrite_strategies/twitter.rb

@@ -0,0 +1,27 @@
+module Downloads
+  module RewriteStrategies
+    class Twitter < Base
+      def rewrite(url, headers, data = {})
+        if url =~ %r!^https?://(?:mobile\.)?twitter\.com!
+          url, headers = rewrite_image_url(url, headers)
+        end
+
+        return [url, headers, data]
+      end
+
+    protected
+      def rewrite_image_url(url, headers)
+        # example: http://twitter.com/status
+        url = url.sub(%r!^https?://twitter\.com!, "http://mobile.twitter.com")
+
+        if url =~ %r!^https?://mobile\.twitter\.com/\w+/status/\d+!
+          source = ::Sources::Strategies::Twitter.new(url)
+          source.get
+          url = source.image_url
+        end
+
+        return [url, headers]
+      end
+    end
+  end
+end

app/logical/sources/site.rb

@@ -6,7 +6,7 @@ module Sources
     delegate :get, :referer_url, :site_name, :artist_name, :profile_url, :image_url, :tags, :artist_record, :unique_id, :page_count, :file_url, :ugoira_frame_data, :to => :strategy
 
     def self.strategies
-      [Strategies::Pixiv, Strategies::NicoSeiga, Strategies::DeviantArt, Strategies::Nijie]
+      [Strategies::Pixiv, Strategies::NicoSeiga, Strategies::DeviantArt, Strategies::Nijie, Strategies::Twitter]
     end
 
     def initialize(url)

app/logical/sources/strategies/twitter.rb

@@ -0,0 +1,53 @@
+module Sources::Strategies
+  class Twitter < Base
+    def self.url_match?(url)
+      url =~ %r!https?://mobile\.twitter\.com/\w+/status/\d+!
+    end
+
+    def tags
+      []
+    end
+
+    def site_name
+      "Twitter"
+    end
+
+    def get
+      agent.get(url) do |page|
+        @artist_name, @profile_url = get_profile_from_page(page)
+        @image_url = get_image_url_from_page(page)
+      end
+    end
+
+    def get_profile_from_page(page)
+      links = page.search("a.profile-link")
+      if links.any?
+        profile_url = "https://twitter.com" + links[0]["href"]
+        artist_name = links[0].search("span")[0].text
+      else
+        profile_url = nil
+        artist_name = nil
+      end
+
+      return [artist_name, profile_url].compact
+    end
+
+    def get_image_url_from_page(page)
+      divs = page.search("div.media")
+
+      if divs.any?
+        image_url = divs.search("img")[0]["src"] + ":large"
+      else
+        image_url = nil
+      end
+
+      return image_url
+    end
+
+    private
+
+    def agent
+      @agent ||= Mechanize.new
+    end
+  end
+end