add support for nico seiga manga (fixes #4060)

app/logical/nico_seiga_manga_api_client.rb

@@ -0,0 +1,58 @@
+class NicoSeigaMangaApiClient
+  extend Memoist
+  BASE_URL = "http://seiga.nicovideo.jp/api"
+  attr_reader :theme_id
+
+  def initialize(theme_id)
+    @theme_id = theme_id
+  end
+
+  def user_id
+    theme_info_xml["response"]["theme"]["user_id"].to_i
+  end
+
+  def title
+    theme_info_xml["response"]["theme"]["title"]
+  end
+
+  def desc
+    theme_info_xml["response"]["theme"]["description"]
+  end
+
+  def moniker
+    artist_xml["response"]["user"]["nickname"]
+  end
+
+  def image_ids
+    theme_data_xml["response"]["image_list"]["image"].map {|x| x["id"]}
+  end
+
+  def tags
+    theme_info_xml["response"]["theme"]["tag_list"]["tag"].map {|x| x["name"]}
+  end
+
+  def theme_data_xml
+    uri = "#{BASE_URL}/theme/data?theme_id=#{theme_id}"
+    body = NicoSeigaApiClient.agent.get(uri).body
+    Hash.from_xml(body)
+  end
+  memoize :theme_data_xml
+
+  def theme_info_xml
+    uri = "#{BASE_URL}/theme/info?id=#{theme_id}"
+    body = NicoSeigaApiClient.agent.get(uri).body
+    Hash.from_xml(body)
+  end
+  memoize :theme_info_xml
+
+  def artist_xml
+    uri = "#{BASE_URL}/user/info?id=#{user_id}"
+    body, code = HttpartyCache.get(uri)
+    if code == 200
+      Hash.from_xml(body)
+    else
+      raise "nico seiga api call failed (code=#{code}, body=#{body})"
+    end
+  end
+  memoize :artist_xml
+end