Add support to unlink lunch flow accounts (#318)

* Add support to unlink lunch flow accounts

* add support to link and unlink to any provider

* Fix tests and query

* Let's keep Amr happy about his brand

* Wrap unlink operations in a transaction and add error handling.

* Fix tests

---------

Co-authored-by: Juan José Mata <juanjo.mata@gmail.com>

test/controllers/accounts_controller_test.rb

@@ -30,7 +30,7 @@ class AccountsControllerTest < ActionDispatch::IntegrationTest
     delete account_url(@account)
     assert_redirected_to accounts_path
     assert_enqueued_with job: DestroyJob
-    assert_equal "Account scheduled for deletion", flash[:notice]
+    assert_equal "Depository account scheduled for deletion", flash[:notice]
   end
 
   test "syncing linked account triggers sync for all provider items" do
@@ -57,4 +57,90 @@ class AccountsControllerTest < ActionDispatch::IntegrationTest
     post sync_account_url(@account)
     assert_redirected_to account_url(@account)
   end
+
+  test "confirms unlink for linked account" do
+    plaid_account = plaid_accounts(:one)
+    AccountProvider.create!(account: @account, provider: plaid_account)
+
+    get confirm_unlink_account_url(@account)
+    assert_response :success
+  end
+
+  test "redirects when confirming unlink for unlinked account" do
+    get confirm_unlink_account_url(@account)
+    assert_redirected_to account_url(@account)
+    assert_equal "Account is not linked to a provider", flash[:alert]
+  end
+
+  test "unlinks linked account successfully with new system" do
+    plaid_account = plaid_accounts(:one)
+    AccountProvider.create!(account: @account, provider: plaid_account)
+    @account.reload
+
+    assert @account.linked?
+
+    delete unlink_account_url(@account)
+    @account.reload
+
+    assert_not @account.linked?
+    assert_redirected_to accounts_path
+    assert_equal "Account unlinked successfully. It is now a manual account.", flash[:notice]
+  end
+
+  test "unlinks linked account successfully with legacy system" do
+    plaid_account = plaid_accounts(:one)
+    @account.update!(plaid_account_id: plaid_account.id)
+    @account.reload
+
+    assert @account.linked?
+
+    delete unlink_account_url(@account)
+    @account.reload
+
+    assert_not @account.linked?
+    assert_nil @account.plaid_account_id
+    assert_redirected_to accounts_path
+    assert_equal "Account unlinked successfully. It is now a manual account.", flash[:notice]
+  end
+
+  test "redirects when unlinking unlinked account" do
+    delete unlink_account_url(@account)
+    assert_redirected_to account_url(@account)
+    assert_equal "Account is not linked to a provider", flash[:alert]
+  end
+
+  test "unlinked account can be deleted" do
+    plaid_account = plaid_accounts(:one)
+    AccountProvider.create!(account: @account, provider: plaid_account)
+    @account.reload
+
+    # Cannot delete while linked
+    delete account_url(@account)
+    assert_redirected_to account_url(@account)
+    assert_equal "Cannot delete a linked account. Please unlink it first.", flash[:alert]
+
+    # Unlink the account
+    delete unlink_account_url(@account)
+    @account.reload
+
+    # Now can delete
+    delete account_url(@account)
+    assert_redirected_to accounts_path
+    assert_enqueued_with job: DestroyJob
+    assert_equal "Depository account scheduled for deletion", flash[:notice]
+  end
+
+  test "select_provider shows available providers" do
+    get select_provider_account_url(@account)
+    assert_response :success
+  end
+
+  test "select_provider redirects for already linked account" do
+    plaid_account = plaid_accounts(:one)
+    AccountProvider.create!(account: @account, provider: plaid_account)
+
+    get select_provider_account_url(@account)
+    assert_redirected_to account_url(@account)
+    assert_equal "Account is already linked to a provider", flash[:alert]
+  end
 end

test/controllers/plaid_items_controller_test.rb

@@ -46,4 +46,45 @@ class PlaidItemsControllerTest < ActionDispatch::IntegrationTest
 
     assert_redirected_to accounts_path
   end
+
+  test "select_existing_account redirects when no available plaid accounts" do
+    account = accounts(:depository)
+
+    get select_existing_account_plaid_items_url(account_id: account.id, region: "us")
+    assert_redirected_to account_path(account)
+    assert_equal "No available Plaid accounts to link. Please connect a new Plaid account first.", flash[:alert]
+  end
+
+  test "link_existing_account links plaid account to existing account" do
+    account = accounts(:depository)
+
+    # Create a new unlinked plaid_account for testing
+    plaid_account = PlaidAccount.create!(
+      plaid_item: plaid_items(:one),
+      name: "Test Plaid Account",
+      plaid_id: "test_acc_123",
+      plaid_type: "depository",
+      plaid_subtype: "checking",
+      currency: "USD",
+      current_balance: 1000,
+      available_balance: 1000
+    )
+
+    assert_not account.linked?
+    assert_nil plaid_account.account
+    assert_nil plaid_account.account_provider
+
+    assert_difference "AccountProvider.count", 1 do
+      post link_existing_account_plaid_items_url, params: {
+        account_id: account.id,
+        plaid_account_id: plaid_account.id
+      }
+    end
+
+    account.reload
+    assert account.linked?, "Account should be linked after creating AccountProvider"
+    assert_equal 1, account.account_providers.count
+    assert_redirected_to accounts_path
+    assert_equal "Account successfully linked to Plaid", flash[:notice]
+  end
 end

test/controllers/simplefin_items_controller_test.rb

@@ -235,4 +235,12 @@ class SimplefinItemsControllerTest < ActionDispatch::IntegrationTest
     @simplefin_item.reload
     assert @simplefin_item.scheduled_for_deletion?
   end
+
+  test "select_existing_account redirects when no available simplefin accounts" do
+    account = accounts(:depository)
+
+    get select_existing_account_simplefin_items_url(account_id: account.id)
+    assert_redirected_to account_path(account)
+    assert_equal "No available SimpleFIN accounts to link. Please connect a new SimpleFIN account first.", flash[:alert]
+  end
 end