integrate ugoiras into zip+webm+preview

app/logical/pixiv_ugoira_converter.rb

@@ -1,43 +1,11 @@
 class PixivUgoiraConverter
-  attr_reader :agent, :url, :write_path, :format
-
-  def initialize(url, write_path, format)
-    @url = url
-    @write_path = write_path
-    @format = format
+  def convert(source_path, output_path, preview_path, frame_data)
+    folder = unpack(File.open(source_path))
+    write_webm(folder, output_path, frame_data)
+    write_preview(folder, preview_path)
   end
 
-  def process!
-    folder = unpack(fetch_zipped_body)
-
-    if format == :gif
-      write_gif(folder)
-    elsif format == :webm
-      write_webm(folder)
-    elsif format == :apng
-      write_apng(folder)
-    end
-  end
-
-  def write_gif(folder)
-    anim = Magick::ImageList.new
-    delay_sum = 0
-    folder.each_with_index do |file, i|
-      image_blob = file.get_input_stream.read
-      image = Magick::Image.from_blob(image_blob).first
-      image.ticks_per_second = 1000
-      delay = @frame_data[i]["delay"]
-      rounded_delay = (delay_sum + delay).round(-1) - delay_sum.round(-1)
-      image.delay = rounded_delay
-      delay_sum += delay
-      anim << image
-    end
-    
-    anim = anim.optimize_layers(Magick::OptimizeTransLayer)
-    anim.write("gif:" + write_path)
-  end
-
-  def write_webm(folder)
+  def write_webm(folder, write_path, frame_data)
     Dir.mktmpdir do |tmpdir|
       FileUtils.mkdir_p("#{tmpdir}/images")
       folder.each_with_index do |file, i|
@@ -62,7 +30,7 @@ class PixivUgoiraConverter
       timecodes_path = File.join(tmpdir, "timecodes.tc")
       File.open(timecodes_path, "w+") do |f|
         f.write("# timecode format v2\n")
-        @frame_data.each do |img|
+        frame_data.each do |img|
           f.write("#{delay_sum}\n")
           delay_sum += img["delay"]
         end
@@ -71,68 +39,21 @@ class PixivUgoiraConverter
       end
 
       ext = folder.first.name.match(/\.(\w{,4})$/)[1]
-      system("ffmpeg -i #{tmpdir}/images/%06d.#{ext} -codec:v libvpx -crf 4 -b:v 5000k -an #{tmpdir}/tmp.webm")
-      system("mkvmerge -o #{write_path} --webm --timecodes 0:#{tmpdir}/timecodes.tc #{tmpdir}/tmp.webm")
+      system("ffmpeg -loglevel quiet -i #{tmpdir}/images/%06d.#{ext} -codec:v libvpx -crf 4 -b:v 5000k -an #{tmpdir}/tmp.webm")
+      system("mkvmerge -q -o #{write_path} --webm --timecodes 0:#{tmpdir}/timecodes.tc #{tmpdir}/tmp.webm")
     end      
   end
 
-  def write_apng(folder)
-    Dir.mktmpdir do |tmpdir|
-      folder.each_with_index do |file, i|
-        frame_path = File.join(tmpdir, "frame#{"%03d" % i}.png")
-        delay_path = File.join(tmpdir, "frame#{"%03d" % i}.txt")
-        image_blob = file.get_input_stream.read
-        delay = @frame_data[i]["delay"]
-        image = Magick::Image.from_blob(image_blob).first
-        image.format = "PNG"
-        image.write(frame_path)
-        File.open(delay_path, "wb") do |f|
-          f.write("delay=#{delay}/1000")
-        end
-      end
-      system("apngasm -o -F #{write_path} #{tmpdir}/frame*.png")
-    end
+  def write_preview(folder, path)
+    file = folder.first
+    image_blob = file.get_input_stream.read
+    image = Magick::Image.from_blob(image_blob).first
+    image.write(path)
   end
 
-  def unpack(zipped_body)
+  def unpack(zip_file)
     folder = Zip::CentralDirectory.new
-    folder.read_from_stream(StringIO.new(zipped_body))
+    folder.read_from_stream(zip_file)
     folder
   end
-
-  def fetch_zipped_body
-    zip_body = nil
-    zip_url, @frame_data = fetch_frames
-
-    Downloads::File.new(zip_url, nil).http_get_streaming do |response|
-      zip_body = response.body
-    end
-
-    zip_body
-  end
-
-  def agent
-    @agent ||= Sources::Strategies::Pixiv.new(url).agent
-  end
-
-  def fetch_frames
-    agent.get(url) do |page|
-      # Get the zip url and frame delay by parsing javascript contained in a <script> tag on the page.
-      # Not a neat solution, but I haven't found any other location that has the frame delays listed.
-      scripts = page.search("body script").find_all do |node|
-        node.text =~ /_ugoira600x600\.zip/
-      end
-
-      if scripts.any?
-        javascript = scripts.first.text
-        json = javascript.match(/;pixiv\.context\.ugokuIllustData\s+=\s+(\{.+?\});(?:$|pixiv\.context)/)[1]
-        data = JSON.parse(json)
-        zip_url = data["src"].sub("_ugoira600x600.zip", "_ugoira1920x1080.zip")
-        frame_data = data["frames"]
-        return [zip_url, frame_data]
-      else
-        raise "Can't find javascript with frame data"
-      end
-    end
-  end
 end