"""Tests for analytics fixes to ensure all transactions are used in statistics."""

import pytest
from datetime import datetime, timedelta
from unittest.mock import Mock, AsyncMock
from fastapi.testclient import TestClient

from leggend.main import create_app
from leggend.services.database_service import DatabaseService


class TestAnalyticsFix:
    """Test analytics fixes for transaction limits"""

    @pytest.fixture
    def client(self):
        app = create_app()
        return TestClient(app)

    @pytest.fixture
    def mock_database_service(self):
        return Mock(spec=DatabaseService)

    @pytest.mark.asyncio
    async def test_transaction_stats_uses_all_transactions(self, client, mock_database_service):
        """Test that transaction stats endpoint uses all transactions (not limited to 100)"""
        # Mock data for 600 transactions (simulating the issue)
        mock_transactions = []
        for i in range(600):
            mock_transactions.append({
                "transactionId": f"txn-{i}",
                "transactionDate": (datetime.now() - timedelta(days=i % 365)).isoformat(),
                "description": f"Transaction {i}",
                "transactionValue": 10.0 if i % 2 == 0 else -5.0,
                "transactionCurrency": "EUR",
                "transactionStatus": "booked",
                "accountId": f"account-{i % 3}",
            })

        mock_database_service.get_transactions_from_db = AsyncMock(return_value=mock_transactions)

        # Test that the endpoint calls get_transactions_from_db with limit=None
        with client as test_client:
            # Replace the database service in the route handler
            from leggend.api.routes import transactions
            original_service = transactions.database_service
            transactions.database_service = mock_database_service

            try:
                response = test_client.get("/api/v1/transactions/stats?days=365")
                
                assert response.status_code == 200
                data = response.json()
                
                # Verify that limit=None was passed to get all transactions
                mock_database_service.get_transactions_from_db.assert_called_once()
                call_args = mock_database_service.get_transactions_from_db.call_args
                assert call_args.kwargs.get("limit") is None, "Stats endpoint should pass limit=None to get all transactions"
                
                # Verify that the response contains stats for all 600 transactions
                assert data["success"] is True
                stats = data["data"]
                assert stats["total_transactions"] == 600, "Should process all 600 transactions, not just 100"
                
                # Verify calculations are correct for all transactions
                expected_income = sum(txn["transactionValue"] for txn in mock_transactions if txn["transactionValue"] > 0)
                expected_expenses = sum(abs(txn["transactionValue"]) for txn in mock_transactions if txn["transactionValue"] < 0)
                
                assert stats["total_income"] == expected_income
                assert stats["total_expenses"] == expected_expenses
                
            finally:
                # Restore original service
                transactions.database_service = original_service

    @pytest.mark.asyncio  
    async def test_analytics_endpoint_returns_all_transactions(self, client, mock_database_service):
        """Test that the new analytics endpoint returns all transactions without pagination"""
        # Mock data for 600 transactions
        mock_transactions = []
        for i in range(600):
            mock_transactions.append({
                "transactionId": f"txn-{i}",
                "transactionDate": (datetime.now() - timedelta(days=i % 365)).isoformat(),
                "description": f"Transaction {i}",
                "transactionValue": 10.0 if i % 2 == 0 else -5.0,
                "transactionCurrency": "EUR",
                "transactionStatus": "booked",
                "accountId": f"account-{i % 3}",
            })

        mock_database_service.get_transactions_from_db = AsyncMock(return_value=mock_transactions)

        with client as test_client:
            # Replace the database service in the route handler
            from leggend.api.routes import transactions
            original_service = transactions.database_service
            transactions.database_service = mock_database_service

            try:
                response = test_client.get("/api/v1/transactions/analytics?days=365")
                
                assert response.status_code == 200
                data = response.json()
                
                # Verify that limit=None was passed to get all transactions
                mock_database_service.get_transactions_from_db.assert_called_once()
                call_args = mock_database_service.get_transactions_from_db.call_args
                assert call_args.kwargs.get("limit") is None, "Analytics endpoint should pass limit=None"
                
                # Verify that all 600 transactions are returned
                assert data["success"] is True
                transactions_data = data["data"]
                assert len(transactions_data) == 600, "Analytics endpoint should return all 600 transactions"
                
            finally:
                # Restore original service
                transactions.database_service = original_service