import unittest
import httpx
import json

class TestMealMath(unittest.TestCase):
    BASE_URL = "http://192.168.130.171:8000/api"
    TOKEN = None
    FOOD_ID_1 = None # Will be populated
    FOOD_1_DATA = None

    @classmethod
    def setUpClass(cls):
        with httpx.Client(timeout=30.0) as client:
            # 1. Login to get token
            login_res = client.post(f"{cls.BASE_URL}/login", json={
                "username": "ferro988",
                "password": "password"
            })
            if login_res.status_code == 200:
                cls.TOKEN = login_res.json()["token"]
            
            # 2. Search for a baseline food (e.g., Chicken)
            search_res = client.get(f"{cls.BASE_URL}/food/search?q=Chicken", headers={
                "Authorization": f"Bearer {cls.TOKEN}"
            })
            if search_res.status_code == 200:
                foods = search_res.json()
                if foods:
                    cls.FOOD_ID_1 = foods[0]["id"]
                    cls.FOOD_1_DATA = foods[0]

    def test_baseline_100g(self):
        """Verify that 100g returns the exact database values."""
        payload = {"items": [{"food_id": self.FOOD_ID_1, "amount_g": 100}]}
        with httpx.Client(timeout=30.0) as client:
            res = client.post(f"{self.BASE_URL}/meal/calculate", json=payload, headers={
                "Authorization": f"Bearer {self.TOKEN}"
            })
            self.assertEqual(res.status_code, 200)
            data = res.json()
            
            # Check macros
            self.assertEqual(data["macros"]["calories"], self.FOOD_1_DATA["calories"])
            self.assertEqual(data["macros"]["protein_g"], self.FOOD_1_DATA["protein_g"])

    def test_half_portion_50g(self):
        """Verify that 50g returns exactly 50% of the database values."""
        payload = {"items": [{"food_id": self.FOOD_ID_1, "amount_g": 50}]}
        with httpx.Client(timeout=30.0) as client:
            res = client.post(f"{self.BASE_URL}/meal/calculate", json=payload, headers={
                "Authorization": f"Bearer {self.TOKEN}"
            })
            self.assertEqual(res.status_code, 200)
            data = res.json()
            
            expected_cal = round(self.FOOD_1_DATA["calories"] * 0.5, 2)
            expected_pro = round(self.FOOD_1_DATA["protein_g"] * 0.5, 2)
            
            self.assertEqual(data["macros"]["calories"], expected_cal)
            self.assertEqual(data["macros"]["protein_g"], expected_pro)

    def test_irregular_portion_237g(self):
        """Verify that 237g correctly applies the ratio (2.37x)."""
        payload = {"items": [{"food_id": self.FOOD_ID_1, "amount_g": 237}]}
        with httpx.Client(timeout=30.0) as client:
            res = client.post(f"{self.BASE_URL}/meal/calculate", json=payload, headers={
                "Authorization": f"Bearer {self.TOKEN}"
            })
            self.assertEqual(res.status_code, 200)
            data = res.json()
            
            ratio = 2.37
            expected_cal = round(self.FOOD_1_DATA["calories"] * ratio, 2)
            
            self.assertEqual(data["macros"]["calories"], expected_cal)

    def test_multi_item_aggregation(self):
        """Verify that two items sum up correctly."""
        with httpx.Client(timeout=30.0) as client:
            # Get a second food
            search_res = client.get(f"{self.BASE_URL}/food/search?q=Rice", headers={
                "Authorization": f"Bearer {self.TOKEN}"
            })
            food2 = search_res.json()[0]
            
            payload = {
                "items": [
                    {"food_id": self.FOOD_ID_1, "amount_g": 100},
                    {"food_id": food2["id"], "amount_g": 200}
                ]
            }
            res = client.post(f"{self.BASE_URL}/meal/calculate", json=payload, headers={
                "Authorization": f"Bearer {self.TOKEN}"
            })
            self.assertEqual(res.status_code, 200)
            data = res.json()
            
            expected_cal = round(self.FOOD_1_DATA["calories"] + (food2["calories"] * 2.0), 2)
            expected_weight = 100 + 200
            
            self.assertEqual(data["macros"]["calories"], expected_cal)
            self.assertEqual(data["total_weight_g"], expected_weight)

if __name__ == "__main__":
    unittest.main()