import urllib.request
import urllib.error
import json

def run_test(name, payload):
    url = "http://127.0.0.1:8000/api/meal/calculate"
    login_url = "http://127.0.0.1:8000/api/login"
    register_url = "http://127.0.0.1:8000/api/register"
    
    print(f"\n--- Testing: {name} ---")
    
    auth_data = json.dumps({"username": "testuser", "password": "password"}).encode('utf-8')
    
    # Try to register first (ignore error if already exists)
    req_reg = urllib.request.Request(register_url, data=auth_data, headers={'Content-Type': 'application/json'})
    try:
        urllib.request.urlopen(req_reg)
    except Exception:
        pass
        
    # Login
    req = urllib.request.Request(login_url, data=auth_data, headers={'Content-Type': 'application/json'})
    try:
        with urllib.request.urlopen(req) as response:
            token = json.loads(response.read().decode()).get("token")
    except Exception as e:
        print(f"Login failed: {e}")
        return

    headers = {"Authorization": f"Bearer {token}", "Content-Type": "application/json"}
    data = json.dumps(payload).encode('utf-8')
    req = urllib.request.Request(url, data=data, headers=headers)
    
    try:
        with urllib.request.urlopen(req) as response:
            print(f"Status: {response.getcode()}")
            print(f"Body: {response.read().decode()}")
    except urllib.error.HTTPError as e:
        print(f"Status: {e.code}")
        print(f"Error Body: {e.read().decode()}")

if __name__ == "__main__":
    # Case 1: amount_g is 0
    run_test("Zero Quantity", {"items": [{"food_id": 1, "amount_g": 0}]})
    
    # Case 2: amount_g is negative
    run_test("Negative Quantity", {"items": [{"food_id": 1, "amount_g": -50}]})
    
    # Case 3: Invalid food_id
    run_test("Invalid Food ID", {"items": [{"food_id": 999999, "amount_g": 100}]})
    
    # Case 4: Mixed valid and invalid IDs
    run_test("Mixed Valid/Invalid IDs", {"items": [
        {"food_id": 1, "amount_g": 100},
        {"food_id": 888888, "amount_g": 200}
    ]})

    # Case 5: Valid request
    run_test("Valid Request", {"items": [{"food_id": 1, "amount_g": 150}]})