Fix crypto subtype for trades api (#1022)

* fix: crypto subtype not persisted by permitting :subtype in CryptosController

* Backfill crypto subtype for existig accounts so Trades API works

* fix: backfill only unlinked cryptos; use raw SQL in migration; deterministic redirect in test

* Update schema.rb for BackfillcryptoSubtypeForTrades migration

---------

Signed-off-by: dataCenter430 <161712630+dataCenter430@users.noreply.github.com>

app/controllers/cryptos_controller.rb

@@ -1,5 +1,5 @@
 class CryptosController < ApplicationController
   include AccountableResource
 
-  permitted_accountable_attributes :id, :tax_treatment
+  permitted_accountable_attributes :id, :subtype, :tax_treatment
 end

db/migrate/20260218120000_backfill_crypto_subtype_for_trades.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+class BackfillCryptoSubtypeForTrades < ActiveRecord::Migration[7.2]
+  def up
+    # Crypto accounts created via the UI before the controller permitted :subtype
+    # had subtype NULL, so supports_trades? was false and the Trades API returned 422.
+    # Backfill to "exchange" only for manual (unlinked) crypto accounts so they can use
+    # the Trades API. Skip accounts linked to a provider (e.g. CoinStats wallet) which
+    # intentionally leave subtype NULL and must remain wallet/sync-only.
+    # Uses raw SQL to avoid coupling to the Crypto model (see Rails migration guidelines).
+    say_with_time "Backfilling crypto subtype for manual accounts only" do
+      execute <<-SQL.squish
+        UPDATE cryptos
+        SET subtype = 'exchange'
+        WHERE subtype IS NULL
+          AND id IN (
+            SELECT a.accountable_id
+            FROM accounts a
+            WHERE a.accountable_type = 'Crypto'
+              AND NOT EXISTS (SELECT 1 FROM account_providers ap WHERE ap.account_id = a.id)
+          )
+      SQL
+    end
+  end
+
+  def down
+    # No-op: we cannot distinguish backfilled records from user-chosen "exchange",
+    # so reverting would incorrectly clear legitimately set subtypes.
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.2].define(version: 2026_02_17_120000) do
+ActiveRecord::Schema[7.2].define(version: 2026_02_18_120000) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "pgcrypto"
   enable_extension "plpgsql"

test/controllers/cryptos_controller_test.rb

@@ -6,5 +6,48 @@ class CryptosControllerTest < ActionDispatch::IntegrationTest
   setup do
     sign_in @user = users(:family_admin)
     @account = accounts(:crypto)
+    @family = @user.family
+  end
+
+  test "create persists subtype so account supports trades" do
+    Family.any_instance.stubs(:get_link_token).returns("test-link-token")
+
+    assert_difference "@family.accounts.count", 1 do
+      post cryptos_path, params: {
+        account: {
+          name: "Crypto Exchange Account",
+          balance: 0,
+          currency: @family.currency,
+          accountable_type: "Crypto",
+          accountable_attributes: { subtype: "exchange", tax_treatment: "taxable" }
+        }
+      }
+    end
+
+    assert_response :redirect
+    created = Account.find(URI(response.location).path.split("/").last)
+    assert_redirected_to created
+    assert_equal "exchange", created.accountable.subtype, "subtype must be persisted for trades API"
+    assert created.supports_trades?, "exchange crypto account must support trades"
+  end
+
+  test "update persists subtype" do
+    @account.accountable.update_column(:subtype, nil)
+    assert_nil @account.reload.accountable.subtype
+    refute @account.supports_trades?
+
+    patch crypto_path(@account), params: {
+      account: {
+        name: @account.name,
+        balance: @account.balance,
+        currency: @account.currency,
+        accountable_attributes: { id: @account.accountable_id, subtype: "exchange", tax_treatment: "taxable" }
+      }
+    }
+
+    assert_redirected_to @account
+    @account.reload
+    assert_equal "exchange", @account.accountable.subtype
+    assert @account.supports_trades?
   end
 end

test/models/crypto_test.rb

@@ -27,4 +27,10 @@ class CryptoTest < ActiveSupport::TestCase
     assert crypto.tax_deferred?
     assert_not crypto.tax_exempt?
   end
+
+  test "supports_trades? is true only for exchange subtype" do
+    assert Crypto.new(subtype: "exchange").supports_trades?
+    refute Crypto.new(subtype: "wallet").supports_trades?
+    refute Crypto.new(subtype: nil).supports_trades?
+  end
 end