Introduce lexicon builder

Gemfile

@@ -6,4 +6,5 @@ gemspec
 gem "i18n"
 gem "rake", "~> 12.0"
 gem "rspec", "~> 3.0"
+gem "builder"
 gem "standard", group: [:development, :test]

Gemfile.lock

@@ -1,13 +1,14 @@
 PATH
   remote: .
   specs:
-    medieval_latina (2.0.6)
+    medieval_latina (2.1.0)
       i18n
 
 GEM
   remote: https://rubygems.org/
   specs:
     ast (2.4.0)
+    builder (3.2.4)
     concurrent-ruby (1.2.2)
     diff-lcs (1.3)
     i18n (1.13.0)
@@ -50,6 +51,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  builder
   i18n
   medieval_latina!
   rake (~> 12.0)

lib/medieval_latina.rb

@@ -1,5 +1,6 @@
 require "medieval_latina/dictionary"
 require "medieval_latina/initializer"
+require "medieval_latina/lexicon_builder"
 require "medieval_latina/version"
 require "set"
 

lib/medieval_latina/lexicon_builder.rb

@@ -0,0 +1,49 @@
+require "builder"
+
+class MedievalLatina
+  class LexiconBuilder
+    def initialize
+      @hash = parts.each_with_object({}) do |part, hash|
+        hash.merge(part)
+      end
+
+      FREQUENCY_LIST.each do |word, metadata|
+        if metadata.key?(:ipa)
+          @hash[word] = metadata[:ipa]
+        end
+      end
+
+      @xml = Builder::XmlMarkup.new(indent: 2)
+    end
+
+    def call
+      xml.instruct! :xml, encoding: "UTF-8"
+      xml.lexicon(xmlns: URL, version: "1.0") do
+        grouped_hash.each do |phonetics, words|
+          xml.lexeme do
+            words.each { |word| xml.grapheme word }
+            xml.phoneme phonetics
+          end
+        end
+      end
+    end
+
+    private
+
+    attr_reader :hash, :xml
+
+    def grouped_hash
+      hash.group_by do |_, phonetics|
+        phonetics
+      end.transform_values do |pairs|
+        pairs.map(&:first)
+      end
+    end
+
+    def parts
+      [ADJECTIVES, ADVERBS, NOUNS, VERBS]
+    end
+
+    URL = "http://www.w3.org/2005/01/pronunciation-lexicon".freeze
+  end
+end

lib/medieval_latina/version.rb

@@ -1,3 +1,3 @@
 class MedievalLatina
-  VERSION = "2.0.6".freeze
+  VERSION = "2.1.0".freeze
 end