"""§6.4 /api/products/* endpoint scenarios (PUC-2/3/3a/4/5/5a/8 + gates)."""
import io
import re
from contextlib import contextmanager

from fastapi.testclient import TestClient

from app.main import create_app

GOOD_CSV = b"Handle,Title,Vendor,Variant Price\nmoon-mug,Moon Mug,Acme,18.00\n"


@contextmanager
def _merchant_client(fresh_db_url, email="m@example.com"):
    with TestClient(create_app(database_url=fresh_db_url)) as client:
        client.post("/api/auth/request-code", json={"email": email})
        code = re.search(r"\b(\d{6})\b", client.app.state.mailer.outbox[-1].body).group(1)
        client.post("/api/auth/verify", json={"email": email, "code": code})
        client.post("/api/storefronts", json={})
        yield client


def _upload(client, data=GOOD_CSV, name="cat.csv"):
    return client.post("/api/products/imports", files={"file": (name, io.BytesIO(data), "text/csv")})


def test_upload_returns_201_draft(fresh_db_url):
    with _merchant_client(fresh_db_url) as client:
        resp = _upload(client)
        assert resp.status_code == 201
        body = resp.json()
        assert body["summary"]["adds"] == 1 and body["dialect"] == "canonical"


def test_upload_rejections_carry_codes(fresh_db_url):
    with _merchant_client(fresh_db_url) as client:
        resp = _upload(client, b"Vendor\nAcme\n")
        assert resp.status_code == 400
        assert resp.json()["error"]["code"] == "missing_required_column"
        resp = _upload(client, b"Handle,Title\n" + b"x" * (10 * 1024 * 1024 + 1))
        assert resp.status_code == 413


def test_unauthenticated_401_and_no_storefront_404(fresh_db_url):
    with TestClient(create_app(database_url=fresh_db_url)) as client:
        assert _upload(client).status_code == 401
        client.post("/api/auth/request-code", json={"email": "x@example.com"})
        code = re.search(r"\b(\d{6})\b", client.app.state.mailer.outbox[-1].body).group(1)
        client.post("/api/auth/verify", json={"email": "x@example.com", "code": code})
        assert _upload(client).status_code == 404


def test_preview_confirm_run_flow(fresh_db_url):
    with _merchant_client(fresh_db_url) as client:
        draft = _upload(client).json()
        recs = client.get(f"/api/products/imports/drafts/{draft['id']}/records").json()["records"]
        assert recs[0]["kind"] == "add"
        run_id = client.post(f"/api/products/imports/drafts/{draft['id']}/confirm").json()["run_id"]
        run = client.get(f"/api/products/imports/runs/{run_id}").json()
        assert run["products_added"] == 1 and run["by"] == "m@example.com"
        assert client.get("/api/products/summary").json()["product_count"] == 1
        assert client.get("/api/products/imports/runs").json()["runs"][0]["id"] == run_id


def test_cancel_no_trace_puc3a(fresh_db_url):
    with _merchant_client(fresh_db_url) as client:
        draft = _upload(client).json()
        assert client.delete(f"/api/products/imports/drafts/{draft['id']}").status_code == 204
        assert client.get(f"/api/products/imports/drafts/{draft['id']}").status_code == 404
        assert client.get("/api/products/imports/runs").json()["runs"] == []


def test_confirm_conflicts(fresh_db_url):
    with _merchant_client(fresh_db_url) as client:
        d1 = _upload(client).json()
        client.post(f"/api/products/imports/drafts/{d1['id']}/confirm")
        d2 = _upload(client).json()
        resp = client.post(f"/api/products/imports/drafts/{d2['id']}/confirm")
        assert resp.status_code == 409 and resp.json()["error"]["code"] == "nothing_to_apply"


def test_sample_csv_served(fresh_db_url):
    with TestClient(create_app(database_url=fresh_db_url)) as client:
        resp = client.get("/api/products/sample.csv")
        assert resp.status_code == 200
        assert resp.headers["content-type"].startswith("text/csv")
        assert resp.text.startswith("Handle,Title,")


def test_sample_csv_imports_clean(fresh_db_url):
    """DOC-3 honesty: our own sample must validate with zero errors."""
    with _merchant_client(fresh_db_url) as client:
        sample = client.get("/api/products/sample.csv").content
        body = _upload(client, sample, "sample.csv").json()
        assert body["summary"]["errors"] == 0 and body["summary"]["adds"] == 2