feat: additional expenses

services/statistics/expenses_statistics.py

@@ -0,0 +1,60 @@
+from datetime import date
+from sqlalchemy import select, func, Subquery, cast
+from sqlalchemy.dialects.postgresql import TIMESTAMP
+from models import PaymentRecord, Expense
+from services.base import BaseService
+from services.statistics.common import generate_date_range
+
+
+class ExpensesStatisticsService(BaseService):
+    date_from: date
+    date_to: date
+
+    def _get_expenses_sub(self, model, date_column, amount_column) -> Subquery:
+        all_dates = generate_date_range(self.date_from, self.date_to, ["expenses"])
+
+        expenses = (
+            select(
+                func.sum(getattr(model, amount_column)).label("expenses"),
+                cast(getattr(model, date_column), TIMESTAMP(timezone=False)).label("date"),
+            )
+            .group_by("date")
+            .subquery()
+        )
+
+        expenses_with_gaps_filled = (
+            select(
+                all_dates.c.date,
+                (all_dates.c.expenses + func.coalesce(expenses.c.expenses, 0)).label("expenses"),
+            )
+            .join(expenses, all_dates.c.date == expenses.c.date, isouter=True)
+            .order_by(all_dates.c.date)
+            .subquery()
+        )
+        return expenses_with_gaps_filled
+
+    def _apply_expenses(self, deals_by_dates: Subquery, expenses_subquery: Subquery):
+        return (
+            select(
+                deals_by_dates.c.date,
+                deals_by_dates.c.deals_count,
+                deals_by_dates.c.revenue,
+                (func.coalesce(deals_by_dates.c.profit, 0) - func.coalesce(expenses_subquery.c.expenses, 0)).label(
+                    "profit"),
+                (deals_by_dates.c.expenses + expenses_subquery.c.expenses).label("expenses"),
+            )
+            .join(expenses_subquery, expenses_subquery.c.date == deals_by_dates.c.date)
+        )
+
+    def apply_expenses(self, date_from: date, date_to: date, deals_by_dates: Subquery):
+        self.date_from, self.date_to = date_from, date_to
+
+        # Apply salary expenses
+        salary_expenses = self._get_expenses_sub(PaymentRecord, "start_date", "amount")
+        deals_by_dates = self._apply_expenses(deals_by_dates, salary_expenses)
+
+        # Apply additional expenses
+        additional_expenses = self._get_expenses_sub(Expense, "spent_date", "amount")
+        deals_by_dates = self._apply_expenses(deals_by_dates, additional_expenses)
+
+        return deals_by_dates