first commit

lib/contact_form.rb

@@ -0,0 +1,36 @@
+class ContactForm
+  LIMITS = {
+    "email" => 254,
+    "name" => 128,
+    "subject" => 200,
+    "message" => 5000
+  }.freeze
+
+  def initialize(params)
+    @params = params
+  end
+
+  def spam?
+    !@params["website"].to_s.empty?
+  end
+
+  def valid?
+    fields_valid = LIMITS.all? do |key, max|
+      value = @params[key]
+
+      value.is_a?(String) &&
+        value.valid_encoding? &&
+        !value.strip.empty? &&
+        value.strip.length <= max
+    end
+
+    return false unless fields_valid
+
+    email_valid = @params["email"].strip.match?(/\A[^\s@]+@[^\s@]+\.[^\s@]+\z/)
+    headers_valid = %w[name subject].none? do |key|
+      @params[key].match?(/[\r\n]/)
+    end
+
+    email_valid && headers_valid
+  end
+end