Add DMCA complaint form.

Add a form for submitting DMCA complaints. The complaint is emailed to
the site owner, and a confirmation email is sent to the submitter.

test/functional/dmcas_controller.rb

@@ -0,0 +1,28 @@
+require "test_helper"
+
+class DmcasControllerTest < ActionDispatch::IntegrationTest
+  context "show action" do
+    should "work for anonymous users" do
+      get dmca_path
+      assert_response :success
+    end
+  end
+
+  context "create action" do
+    should "work" do
+      dmca = {
+        name: "John Doe",
+        email: "test@example.com",
+        address: "123 Fake Street",
+        infringing_urls: "https://example.com/1.html\nhttps://example.com/2.html",
+        original_urls: "https://google.com/1.html\nhttps://google.com/2.html",
+        proof: "source: me",
+        signature: "John Doe",
+      }
+
+      post dmca_path, params: { dmca: dmca }
+      assert_response :success
+      assert_emails 2
+    end
+  end
+end

test/mailers/previews/user_mailer_preview.rb

@@ -1,21 +1,36 @@
 class UserMailerPreview < ActionMailer::Preview
   def dmail_notice
-    dmail = User.system.dmails.first
+    user = params[:id].present? ? User.find(params[:id]) : User.owner
+    dmail = Dmail.received.order(id: :desc).offset(279).first
     UserMailer.dmail_notice(dmail)
   end
 
   def password_reset
-    user = User.find(params[:id])
+    user = params[:id].present? ? User.find(params[:id]) : User.owner
     UserMailer.password_reset(user)
   end
 
   def email_change_confirmation
-    user = User.find(params[:id])
+    user = params[:id].present? ? User.find(params[:id]) : User.owner
     UserMailer.email_change_confirmation(user)
   end
 
   def welcome_user
-    user = User.find(params[:id])
+    user = params[:id].present? ? User.find(params[:id]) : User.owner
     UserMailer.welcome_user(user)
   end
+
+  def dmca_complaint
+    dmca = {
+      name: "John Doe",
+      email: "test@example.com",
+      address: "123 Fake Street",
+      infringing_urls: "https://example.com/1.html\nhttps://example.com/2.html",
+      original_urls: "https://google.com/1.html\nhttps://google.com/2.html",
+      proof: "source: me",
+      signature: "John Doe",
+    }
+
+    UserMailer.with(dmca: dmca).dmca_complaint(to: dmca[:email])
+  end
 end

test/unit/user_mailer_test.rb

@@ -68,5 +68,22 @@ class UserMailerTest < ActionMailer::TestCase
         assert_emails(0) { mail.deliver_now }
       end
     end
+
+    context "dmail_complaint method" do
+      should "work" do
+        dmca = {
+          name: "John Doe",
+          email: "test@example.com",
+          address: "123 Fake Street",
+          infringing_urls: "https://example.com/1.html\nhttps://example.com/2.html",
+          original_urls: "https://google.com/1.html\nhttps://google.com/2.html",
+          proof: "source: me",
+          signature: "John Doe",
+        }
+
+        mail = UserMailer.with(dmca: dmca).dmca_complaint(to: dmca[:email])
+        assert_emails(1) { mail.deliver_now }
+      end
+    end
   end
 end