Introduction of TextSentinel to enforce title and body quality.

lib/text_sentinel.rb

@@ -0,0 +1,56 @@
+require 'iconv'
+
+#
+# Given a string, tell us whether or not is acceptable. Also, remove stuff we don't like
+# such as leading / trailing space.
+#
+class TextSentinel
+
+  attr_accessor :text
+
+  def self.non_symbols_regexp
+    /[\ -\/\[-\`\:-\@\{-\~]/m
+  end
+
+  def initialize(text, opts=nil)
+    if text.present?
+      @text = Iconv.new('UTF-8//IGNORE', 'UTF-8').iconv(text.dup)
+    end
+
+    @opts = opts || {}
+
+    if @text.present?
+      @text.strip! 
+      @text.gsub!(/ +/m, ' ') if @opts[:remove_interior_spaces]
+    end
+  end
+
+  # Entropy is a number of how many unique characters the string needs. 
+  def entropy
+    return 0 if @text.blank?
+    @entropy ||= @text.each_char.to_a.uniq.size
+  end
+
+  def valid?    
+
+    # Blank strings are not valid
+    return false if @text.blank?
+
+    # Entropy check if required
+    return false if @opts[:min_entropy].present? and (entropy < @opts[:min_entropy])
+
+    # We don't have a comprehensive list of symbols, but this will eliminate some noise
+    non_symbols = @text.gsub(TextSentinel.non_symbols_regexp, '').size
+    return false if non_symbols == 0
+
+    # Don't allow super long strings without spaces
+
+    return false if @opts[:max_word_length] and @text =~ /\w{#{@opts[:max_word_length]},}(\s|$)/
+
+    # We don't allow all upper case content
+    return false if @text == @text.upcase
+
+    true
+  end
+
+end