Update GranblueWiki

This is an adaptation and cleanup of the original GranblueWiki class. We extracted the object-related code into a parser, and this class is now only responsible for requests and fetching common property maps.

app/helpers/granblue_wiki.rb

@@ -0,0 +1,103 @@
+# frozen_string_literal: true
+
+require 'httparty'
+
+# GranblueWiki fetches and parses data from gbf.wiki
+class GranblueWiki
+  class_attribute :base_uri
+
+  class_attribute :proficiencies
+  class_attribute :elements
+  class_attribute :rarities
+  class_attribute :genders
+  class_attribute :races
+  class_attribute :boolean
+
+  self.base_uri = 'https://gbf.wiki/api.php'
+
+  self.proficiencies = {
+    'Sabre' => 1,
+    'Dagger' => 2,
+    'Axe' => 3,
+    'Spear' => 4,
+    'Bow' => 5,
+    'Staff' => 6,
+    'Melee' => 7,
+    'Harp' => 8,
+    'Gun' => 9,
+    'Katana' => 10
+  }.freeze
+
+  self.elements = {
+    'Wind' => 1,
+    'Fire' => 2,
+    'Water' => 3,
+    'Earth' => 4,
+    'Dark' => 5,
+    'Light' => 6
+  }.freeze
+
+  self.rarities = {
+    'R' => 1,
+    'SR' => 2,
+    'SSR' => 3
+  }.freeze
+
+  self.races = {
+    'Other' => 0,
+    'Human' => 1,
+    'Erune' => 2,
+    'Draph' => 3,
+    'Harvin' => 4,
+    'Primal' => 5
+  }.freeze
+
+  self.genders = {
+    'o' => 0,
+    'm' => 1,
+    'f' => 2,
+    'mf' => 3
+  }.freeze
+
+  self.boolean = {
+    'yes' => true,
+    'no' => false
+  }.freeze
+
+  def fetch(page)
+    query_params = params(page).map do |key, value|
+      "#{key}=#{value}"
+    end.join('&')
+
+    destination = "#{base_uri}?#{query_params}"
+    response = HTTParty.get(destination)
+
+    handle_response(response, page)
+  end
+
+  private
+
+  def handle_response(response, page)
+    case response.code
+    when 200
+      if response.key?('error')
+        raise WikiError.new(code: response['error']['code'],
+                            message: response['error']['info'],
+                            page: page)
+      end
+
+      response['parse']['wikitext']['*']
+    when 404 then puts "Page #{page} not found"
+    when 500...600 then puts "Server error: #{response.code}"
+    end
+  end
+
+  def params(page)
+    {
+      action: 'parse',
+      format: 'json',
+      page: page,
+      prop: 'wikitext'
+    }
+  end
+end