import os
import tempfile

import pytest
from fastapi.testclient import TestClient
from main import app, init_db


def setup_module(module):
    fd, path = tempfile.mkstemp(suffix=".db")
    os.close(fd)
    module.TEST_DB_PATH = path
    os.environ["DB_PATH"] = path
    init_db()


def teardown_module(module):
    path = getattr(module, "TEST_DB_PATH", None)
    if path and os.path.exists(path):
        os.remove(path)


client = TestClient(app)

def test_root():
    r = client.get("/")
    assert r.status_code == 200
    assert r.json() == {"message": "Shopping List API"}

def test_product_crud():
    # Create
    r = client.post("/products", json={"name": "Paper Plates", "sku": "PP-001"})
    assert r.status_code == 201
    product = r.json()
    assert product["name"] == "Paper Plates"
    assert product["sku"] == "PP-001"
    product_id = product["id"]

    # List
    r = client.get("/products")
    assert r.status_code == 200
    assert len(r.json()) >= 1
    assert any(p["id"] == product_id for p in r.json())

    # Get
    r = client.get(f"/products/{product_id}")
    assert r.status_code == 200
    assert r.json()["id"] == product_id

    # Delete
    r = client.delete(f"/products/{product_id}")
    assert r.status_code == 200
    assert r.json()["deleted"] == product_id

    # Get deleted -> 404
    r = client.get(f"/products/{product_id}")
    assert r.status_code == 404

def test_list_crud():
    # Create
    r = client.post("/lists", json={"name": "Picnic List"})
    assert r.status_code == 201
    lst = r.json()
    assert lst["name"] == "Picnic List"
    list_id = lst["id"]

    # List
    r = client.get("/lists")
    assert r.status_code == 200
    assert any(l["id"] == list_id for l in r.json())

    # Get empty items
    r = client.get(f"/lists/{list_id}")
    assert r.status_code == 200
    assert r.json()["items"] == []

    # Delete
    r = client.delete(f"/lists/{list_id}")
    assert r.status_code == 200
    assert r.json()["deleted"] == list_id

def test_list_items_flow():
    # Create two products
    r1 = client.post("/products", json={"name": "Paper Plates"})
    r2 = client.post("/products", json={"name": "Bread"})
    p1 = r1.json()
    p2 = r2.json()
    p1_id, p2_id = p1["id"], p2["id"]

    # Create a list
    r = client.post("/lists", json={"name": "Picnic List"})
    lst = r.json()
    list_id = lst["id"]

    # Add items
    r = client.post(f"/lists/{list_id}/items", json={"product_id": p1_id, "quantity": 2})
    assert r.status_code == 201
    item1 = r.json()
    assert item1["product_id"] == p1_id
    assert item1["quantity"] == 2

    r = client.post(f"/lists/{list_id}/items", json={"product_id": p2_id, "quantity": 1})
    item2 = r.json()
    assert r.status_code == 201
    assert item2["product_id"] == p2_id
    assert item2["quantity"] == 1

    # List items
    r = client.get(f"/lists/{list_id}/items")
    assert r.status_code == 200
    items = r.json()
    assert len(items) == 2
    qty_by_prod = {i["product_id"]: i["quantity"] for i in items}
    assert qty_by_prod[p1_id] == 2
    assert qty_by_prod[p2_id] == 1

    # Get list with items
    r = client.get(f"/lists/{list_id}")
    assert r.status_code == 200
    data = r.json()
    assert len(data["items"]) == 2
    assert any(i["product_name"] == "Paper Plates" for i in data["items"])

    # Update quantity
    r = client.patch(f"/lists/{list_id}/items/{item1['id']}", json={"quantity": 5})
    assert r.status_code == 200
    assert r.json()["quantity"] == 5

    # Delete item
    r = client.delete(f"/lists/{list_id}/items/{item2['id']}")
    assert r.status_code == 200

    # Verify item2 gone
    r = client.get(f"/lists/{list_id}/items")
    assert r.status_code == 200
    assert len(r.json()) == 1

    # Delete list cascades items
    r = client.delete(f"/lists/{list_id}")
    assert r.status_code == 200

    r = client.get(f"/lists/{list_id}")
    assert r.status_code == 404