Recurring scoping implementation (#1300)

* Recurring scoping implementation

* FIX tests and reviews

db/migrate/20260326112218_add_account_id_to_recurring_transactions.rb

@@ -0,0 +1,64 @@
+class AddAccountIdToRecurringTransactions < ActiveRecord::Migration[7.2]
+  def up
+    add_reference :recurring_transactions, :account, type: :uuid, null: true, foreign_key: true
+
+    # Backfill account_id from the most recent matching entry
+    execute <<~SQL
+      UPDATE recurring_transactions rt
+      SET account_id = subquery.account_id
+      FROM (
+        SELECT DISTINCT ON (rt2.id) rt2.id AS recurring_transaction_id, e.account_id
+        FROM recurring_transactions rt2
+        JOIN entries e ON e.entryable_type = 'Transaction'
+          AND e.currency = rt2.currency
+          AND e.amount = rt2.amount
+          AND EXTRACT(DAY FROM e.date) BETWEEN GREATEST(rt2.expected_day_of_month - 2, 1) AND LEAST(rt2.expected_day_of_month + 2, 31)
+        JOIN accounts a ON a.id = e.account_id AND a.family_id = rt2.family_id
+        LEFT JOIN transactions t ON t.id = e.entryable_id
+        WHERE rt2.account_id IS NULL
+          AND (
+            (rt2.merchant_id IS NOT NULL AND t.merchant_id = rt2.merchant_id)
+            OR (rt2.merchant_id IS NULL AND e.name = rt2.name)
+          )
+        ORDER BY rt2.id, e.date DESC
+      ) subquery
+      WHERE rt.id = subquery.recurring_transaction_id
+    SQL
+
+    # Remove old unique indexes
+    remove_index :recurring_transactions, name: "idx_recurring_txns_merchant", if_exists: true
+    remove_index :recurring_transactions, name: "idx_recurring_txns_name", if_exists: true
+
+    # Add new unique indexes that include account_id
+    add_index :recurring_transactions,
+      [ :family_id, :account_id, :merchant_id, :amount, :currency ],
+      unique: true,
+      where: "merchant_id IS NOT NULL",
+      name: "idx_recurring_txns_acct_merchant"
+
+    add_index :recurring_transactions,
+      [ :family_id, :account_id, :name, :amount, :currency ],
+      unique: true,
+      where: "name IS NOT NULL AND merchant_id IS NULL",
+      name: "idx_recurring_txns_acct_name"
+  end
+
+  def down
+    remove_index :recurring_transactions, name: "idx_recurring_txns_acct_merchant", if_exists: true
+    remove_index :recurring_transactions, name: "idx_recurring_txns_acct_name", if_exists: true
+
+    add_index :recurring_transactions,
+      [ :family_id, :merchant_id, :amount, :currency ],
+      unique: true,
+      where: "merchant_id IS NOT NULL",
+      name: "idx_recurring_txns_merchant"
+
+    add_index :recurring_transactions,
+      [ :family_id, :name, :amount, :currency ],
+      unique: true,
+      where: "name IS NOT NULL AND merchant_id IS NULL",
+      name: "idx_recurring_txns_name"
+
+    remove_reference :recurring_transactions, :account
+  end
+end