feat: additional expenses

services/expenses.py

@@ -0,0 +1,85 @@
+from datetime import datetime
+from typing import Optional
+
+import math
+from fastapi import HTTPException
+from sqlalchemy import delete, select, func
+from fastapi import status
+
+from models import User
+from models.expense import Expense
+from schemas.base import PaginationSchema, PaginationInfoSchema
+from schemas.expense import UpdateExpenseResponse, UpdateExpenseRequest, DeleteExpenseResponse, GetAllExpensesResponse
+from services.base import BaseService
+from utils.dependecies import is_valid_pagination
+
+
+class ExpensesService(BaseService):
+    async def get_all(self, pagination: PaginationSchema) -> GetAllExpensesResponse:
+        if not is_valid_pagination(pagination):
+            raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail='Invalid pagination')
+        page = max(0, pagination.page - 1)
+
+        stmt = (
+            select(Expense)
+            .order_by(Expense.spent_date.desc())
+            .offset(page * pagination.items_per_page)
+            .limit(pagination.items_per_page)
+        )
+
+        total_records = await self.session.scalar(select(func.count()).select_from(Expense))
+        if not total_records:
+            return GetAllExpensesResponse(
+                expenses=[],
+                pagination_info=PaginationInfoSchema()
+            )
+        total_items = total_records
+        total_pages = math.ceil(total_records / pagination.items_per_page)
+
+        expenses = await self.session.execute(stmt)
+        expenses = expenses.scalars().all()
+        response = GetAllExpensesResponse(
+            expenses=expenses,
+            pagination_info=PaginationInfoSchema(
+                total_items=total_items,
+                total_pages=total_pages
+            )
+        )
+        return response
+
+    async def get_by_id(self, expense_id) -> Optional[Expense]:
+        expense = await self.session.get(Expense, expense_id)
+        return expense
+
+    async def update_expense(self, user: User, request: UpdateExpenseRequest) -> UpdateExpenseResponse:
+        expense = await self.get_by_id(request.expense.id)
+
+        if not expense:
+            expense = Expense(
+                created_at=datetime.now(),
+                name=request.expense.name,
+                comment=request.expense.comment,
+                amount=request.expense.amount,
+                spent_date=request.expense.spent_date,
+                created_by_user_id=user.id,
+            )
+            self.session.add(expense)
+            await self.session.commit()
+            return UpdateExpenseResponse(ok=True, message='Запись о расходах успешно создана')
+
+        expense.name = request.expense.name
+        expense.amount = request.expense.amount
+        expense.comment = request.expense.comment
+        expense.spent_date = request.expense.spent_date
+        self.session.add(expense)
+        await self.session.commit()
+        return UpdateExpenseResponse(ok=True, message='Запись о расходах успешно изменена')
+
+    async def delete_expense(self, expense_id) -> DeleteExpenseResponse:
+        stmt = (
+            delete(Expense)
+            .where(Expense.id == expense_id)
+        )
+        await self.session.execute(stmt)
+        await self.session.commit()
+        return DeleteExpenseResponse(ok=True, message='Запись о расходах успешно удалена')