"""Teste US-009 (PRD 3.3): CSRF token per-sesiune + rate-limit signup."""

from __future__ import annotations

import pytest
from fastapi import FastAPI, Request
from fastapi.responses import HTMLResponse
from starlette.middleware.sessions import SessionMiddleware
from starlette.testclient import TestClient


# ---- App minimal pentru teste CSRF ----

def _make_csrf_app() -> FastAPI:
    mini = FastAPI()
    mini.add_middleware(
        SessionMiddleware,
        secret_key="csrf-test-secret",
        session_cookie="autopass_session",
        https_only=False,
        same_site="strict",
    )

    @mini.get("/login-sim")
    def login_sim(request: Request):
        """Simuleaza login: seteaza account_id in sesiune (ca set_session din US-003)."""
        from app.web.csrf import get_csrf_token
        request.session["account_id"] = 1
        return {"token": get_csrf_token(request)}

    @mini.get("/csrf-token")
    def get_token(request: Request):
        from app.web.csrf import get_csrf_token
        return {"token": get_csrf_token(request)}

    @mini.post("/verify-csrf")
    async def verify(request: Request):
        from app.web.csrf import verify_csrf
        form = await request.form()
        submitted = form.get("csrf_token")
        verify_csrf(request, submitted)
        return {"ok": True}

    from app.web.csrf import CsrfError

    @mini.exception_handler(CsrfError)
    async def csrf_handler(request: Request, exc: CsrfError):
        return HTMLResponse("CSRF invalid", status_code=403)

    return mini


@pytest.fixture()
def csrf_client():
    app = _make_csrf_app()
    with TestClient(app, follow_redirects=False) as c:
        yield c


def test_get_csrf_token_stabil_per_sesiune(csrf_client):
    """get_csrf_token intoarce acelasi token in cadrul aceleiasi sesiuni."""
    r1 = csrf_client.get("/csrf-token")
    token1 = r1.json()["token"]
    r2 = csrf_client.get("/csrf-token")
    token2 = r2.json()["token"]
    assert token1 == token2
    assert len(token1) > 16


def test_verify_csrf_corect(csrf_client):
    """Token corect -> verify_csrf trece, raspuns 200."""
    token = csrf_client.get("/csrf-token").json()["token"]
    resp = csrf_client.post("/verify-csrf", data={"csrf_token": token})
    assert resp.status_code == 200


def test_verify_csrf_gresit_ridica(csrf_client):
    """Token gresit -> CsrfError -> 403.

    CSRF se enforce doar cand exista sesiune autentificata (account_id in sesiune).
    login-sim seteaza account_id + csrf_token, ca login-ul real din US-003.
    """
    csrf_client.get("/login-sim")  # initializeaza sesiunea autentificata (account_id + csrf_token)
    resp = csrf_client.post("/verify-csrf", data={"csrf_token": "token-fals-xxxx"})
    assert resp.status_code == 403


def test_verify_csrf_lipsa_ridica(csrf_client):
    """Token lipsa (None) -> CsrfError -> 403."""
    csrf_client.get("/login-sim")  # initializeaza sesiunea autentificata
    resp = csrf_client.post("/verify-csrf", data={})
    assert resp.status_code == 403


def test_verify_csrf_enforce_in_prod_fara_login(monkeypatch):
    """web_auth_required=True -> CSRF enforce chiar fara account_id (login CSRF fix).

    In prod, POST /login si /signup NU au account_id in sesiune, dar CSRF trebuie
    enforced (login CSRF: atacatorul forteaza victima sa se logheze in contul lui).
    Verifica ca verify_csrf ridica CsrfError pe POST fara token, si trece cu token valid.
    """
    import tempfile, os
    tmp = tempfile.mkdtemp()
    monkeypatch.setenv("AUTOPASS_DB_PATH", os.path.join(tmp, "csrf_prod.db"))
    monkeypatch.setenv("AUTOPASS_WEB_AUTH_REQUIRED", "true")
    from app.config import get_settings
    get_settings.cache_clear()

    from fastapi import FastAPI, Request
    from fastapi.responses import HTMLResponse
    from starlette.middleware.sessions import SessionMiddleware
    from starlette.testclient import TestClient
    from app.web.csrf import CsrfError, get_csrf_token, verify_csrf

    mini = FastAPI()
    mini.add_middleware(SessionMiddleware, secret_key="prod-test-key",
                        session_cookie="autopass_session", https_only=False, same_site="strict")

    @mini.get("/form")
    def form(request: Request):
        return {"token": get_csrf_token(request)}

    @mini.post("/form")
    async def form_post(request: Request):
        form = await request.form()
        verify_csrf(request, form.get("csrf_token"))
        return {"ok": True}

    @mini.exception_handler(CsrfError)
    async def csrf_handler(request: Request, exc: CsrfError):
        return HTMLResponse("CSRF invalid", status_code=403)

    with TestClient(mini, follow_redirects=False) as c:
        # GET initializeaza token in sesiune (fara account_id, ca /login GET)
        tok = c.get("/form").json()["token"]

        # POST fara token -> 403 in prod (login CSRF protectie)
        r_bad = c.post("/form", data={})
        assert r_bad.status_code == 403, f"asteptat 403, primit {r_bad.status_code}"

        # POST cu token valid -> 200
        r_ok = c.post("/form", data={"csrf_token": tok})
        assert r_ok.status_code == 200, f"asteptat 200, primit {r_ok.status_code}"

    get_settings.cache_clear()


# ---- Teste rate-limit ----

def test_rate_limit_permite_sub_prag():
    """check_rate_limit permite N cereri sub prag."""
    from app.web.ratelimit import check_rate_limit
    key = "ip_test_sub_prag_unic"
    for _ in range(3):
        assert check_rate_limit(key, max_hits=5, window_s=3600) is True


def test_rate_limit_blocheaza_peste_prag():
    """check_rate_limit blocheaza la a (max_hits+1)-a cerere."""
    from app.web.ratelimit import check_rate_limit
    key = "ip_test_bloc_unic"
    for _ in range(3):
        check_rate_limit(key, max_hits=3, window_s=3600)
    # A 4-a cerere -> False
    assert check_rate_limit(key, max_hits=3, window_s=3600) is False


def test_rate_limit_fereastra_glisanta():
    """Dupa expirarea ferestrei, limiterul permite din nou."""
    import time
    from app.web.ratelimit import check_rate_limit
    key = "ip_test_fereastra_unic"
    # Umple fereastra cu window_s=0 (toate timestamp-urile expira imediat)
    check_rate_limit(key, max_hits=1, window_s=0)
    check_rate_limit(key, max_hits=1, window_s=0)
    # Cu window_s=0 toate sunt expirate -> urmatoarea e permisa
    assert check_rate_limit(key, max_hits=1, window_s=0) is True