# SPDX-License-Identifier: AGPL-3.0-or-later
"""HTTP surface coverage for the canary worker.

We exercise the FastAPI app via Starlette's TestClient so the test
doesn't need a real socket. Asserts:

* ``GET /c/{slug}`` for a known slug returns 200 + image/gif, persists
  a trigger row, bumps the token's counters, and publishes
  ``canary.<token_id>.triggered`` on the bus.
* ``GET /c/{slug}`` for an unknown slug returns the same 200 (stealth)
  but persists nothing.
* The Server header is rewritten to a generic value (``nginx``).
* Bare root returns 404.
* X-Forwarded-For is honored.
"""
from __future__ import annotations

import asyncio
from typing import AsyncIterator

import pytest
import pytest_asyncio
from fastapi.testclient import TestClient

from decnet.bus import topics
from decnet.bus.fake import FakeBus
from decnet.canary.worker import _build_app
from decnet.web.db.sqlite.repository import SQLiteRepository
import decnet.web.db.models  # noqa: F401


@pytest_asyncio.fixture
async def repo(tmp_path) -> AsyncIterator[SQLiteRepository]:
    r = SQLiteRepository(str(tmp_path / "w.db"))
    await r.initialize()
    yield r


@pytest_asyncio.fixture
async def bus() -> AsyncIterator[FakeBus]:
    b = FakeBus()
    await b.connect()
    yield b
    await b.close()


@pytest.mark.asyncio
async def test_known_slug_records_trigger_and_publishes(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    await repo.create_canary_token({
        "uuid": "tok-w1", "kind": "http", "decky_name": "web1",
        "generator": "env_file", "placement_path": "/x",
        "callback_token": "slug-W1", "secret_seed": "s", "created_by": "u1",
    })
    sub = bus.subscribe("canary.>")
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        resp = client.get("/c/slug-W1", headers={"User-Agent": "curl/8.0"})
    assert resp.status_code == 200
    assert resp.headers["content-type"].startswith("image/gif")
    assert resp.headers.get("server") == "nginx"

    event = await asyncio.wait_for(sub.__anext__(), timeout=2.0)
    assert event.topic == topics.canary("tok-w1", topics.CANARY_TRIGGERED)
    assert event.payload["src_ip"]
    assert event.payload["user_agent"] == "curl/8.0"

    triggers = await repo.list_canary_triggers("tok-w1")
    assert len(triggers) == 1
    assert triggers[0]["request_path"] == "/c/slug-W1"

    tok = await repo.get_canary_token("tok-w1")
    assert tok["trigger_count"] == 1


@pytest.mark.asyncio
async def test_unknown_slug_returns_same_response_but_persists_nothing(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        resp = client.get("/c/unknown-slug")
    assert resp.status_code == 200
    assert resp.headers["content-type"].startswith("image/gif")
    # No tokens, no triggers, no nothing.
    assert await repo.list_canary_tokens() == []


@pytest.mark.asyncio
async def test_root_returns_404(repo: SQLiteRepository, bus: FakeBus) -> None:
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        resp = client.get("/")
    assert resp.status_code == 404


@pytest.mark.asyncio
async def test_xff_is_honored(repo: SQLiteRepository, bus: FakeBus) -> None:
    await repo.create_canary_token({
        "uuid": "tok-xff", "kind": "http", "decky_name": "web1",
        "generator": "env_file", "placement_path": "/x",
        "callback_token": "slug-xff", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get("/c/slug-xff", headers={"X-Forwarded-For": "9.9.9.9, 10.0.0.1"})
    triggers = await repo.list_canary_triggers("tok-xff")
    assert triggers[0]["src_ip"] == "9.9.9.9"


@pytest.mark.asyncio
async def test_fingerprint_query_param_decoded_into_raw_headers(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    """``?d=<b64url(json)>`` is decoded into raw_headers["_fp"] when valid."""
    import base64
    import json
    import uuid as _uuid

    _MINT_NS = _uuid.UUID("a3f7c821-9d1e-4b6a-8c2d-1e4f9a7b3c5d")
    mint_id = str(_uuid.uuid5(_MINT_NS, "slug-FP1"))
    await repo.create_canary_token({
        "uuid": "tok-fp1", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-FP1", "secret_seed": "s", "created_by": "u1",
    })
    # Token has no fingerprint_nonce → Layer A skipped; must satisfy B + C.
    fp = {
        "mint": mint_id,
        "nav": {"ua": "Test/1.0"}, "scr": {"w": 1920}, "tz": {"z": "UTC"},
        "id": "h" * 64,
    }
    blob = base64.urlsafe_b64encode(json.dumps(fp).encode()).rstrip(b"=").decode()
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get(f"/c/slug-FP1?d={blob}")
    triggers = await repo.list_canary_triggers("tok-fp1")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp"] == fp


@pytest.mark.asyncio
async def test_bare_open_beacon_records_fp_open_flag(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    import json
    await repo.create_canary_token({
        "uuid": "tok-fp2", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-FP2", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get("/c/slug-FP2?o=1")
    triggers = await repo.list_canary_triggers("tok-fp2")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_open"] == "1"


@pytest.mark.asyncio
async def test_chunked_fingerprint_stores_metadata(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    import json
    await repo.create_canary_token({
        "uuid": "tok-fp3", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-FP3", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get("/c/slug-FP3?s=abc&i=0&n=2&d=Zm9vYmFy")
    triggers = await repo.list_canary_triggers("tok-fp3")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_sid"] == "abc"
    assert headers["_fp_idx"] == "0"
    assert headers["_fp_total"] == "2"
    assert headers["_fp_chunk"] == "Zm9vYmFy"
    # Single-shot decode should NOT have run for a chunked payload.
    assert "_fp" not in headers


@pytest.mark.asyncio
async def test_malformed_fingerprint_records_decode_error(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    import json
    await repo.create_canary_token({
        "uuid": "tok-fp4", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-FP4", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        # base64-decodable but not JSON
        client.get("/c/slug-FP4?d=Zm9vYmFy")  # "foobar"
    triggers = await repo.list_canary_triggers("tok-fp4")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_decode_error"] == "1"
    assert "_fp" not in headers


@pytest.mark.asyncio
async def test_oversize_fingerprint_dropped(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    import json
    await repo.create_canary_token({
        "uuid": "tok-fp5", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-FP5", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        # 9KB blob exceeds the 8KB per-chunk cap
        client.get("/c/slug-FP5?d=" + "A" * (9 * 1024))
    triggers = await repo.list_canary_triggers("tok-fp5")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_oversize"] == "1"
    assert "_fp" not in headers


def _make_fp_blob(slug: str, extra_keys: int = 3) -> tuple[str, str]:
    """Return (b64url_blob, mint_uuid) for a fingerprint matching *slug*."""
    import base64
    import json
    import uuid as _uuid

    _MINT_NS = _uuid.UUID("a3f7c821-9d1e-4b6a-8c2d-1e4f9a7b3c5d")
    mint_id = str(_uuid.uuid5(_MINT_NS, slug))
    base_keys = ["nav", "scr", "tz", "cv", "gl"]
    fp: dict = {"mint": mint_id}
    for k in base_keys[:extra_keys]:
        fp[k] = {"ok": True}
    fp["id"] = "a" * 64
    blob = base64.urlsafe_b64encode(json.dumps(fp).encode()).rstrip(b"=").decode()
    return blob, mint_id


@pytest.mark.asyncio
async def test_fp_valid_nonce_persists(repo: SQLiteRepository, bus: FakeBus) -> None:
    """Valid nonce + valid shape + correct mint UUID → ``_fp`` is persisted."""
    import json

    blob, _ = _make_fp_blob("slug-NONCE1")
    await repo.create_canary_token({
        "uuid": "tok-n1", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-NONCE1", "secret_seed": "s", "created_by": "u1",
        "fingerprint_nonce": "deadbeef01234567",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get(f"/c/slug-NONCE1?d={blob}&k=deadbeef01234567")
    triggers = await repo.list_canary_triggers("tok-n1")
    headers = json.loads(triggers[0]["raw_headers"])
    assert "_fp" in headers
    assert "_fp_invalid_nonce" not in headers
    # Valid fingerprint → token auto-revoked.
    tok = await repo.get_canary_token("tok-n1")
    assert tok["state"] == "revoked"


@pytest.mark.asyncio
async def test_fp_invalid_nonce_rejected(repo: SQLiteRepository, bus: FakeBus) -> None:
    """Wrong ``?k=`` value → ``_fp_invalid_nonce=1``, no ``_fp``."""
    import json

    blob, _ = _make_fp_blob("slug-NONCE2")
    await repo.create_canary_token({
        "uuid": "tok-n2", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-NONCE2", "secret_seed": "s", "created_by": "u1",
        "fingerprint_nonce": "deadbeef01234567",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get(f"/c/slug-NONCE2?d={blob}&k=wrongnonce000000")
    triggers = await repo.list_canary_triggers("tok-n2")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_invalid_nonce"] == "1"
    assert "_fp" not in headers


@pytest.mark.asyncio
async def test_fp_invalid_shape_rejected(repo: SQLiteRepository, bus: FakeBus) -> None:
    """Fewer than 3 known dict keys → ``_fp_invalid_shape=1``, no ``_fp``."""
    import base64
    import json
    import uuid as _uuid

    _MINT_NS = _uuid.UUID("a3f7c821-9d1e-4b6a-8c2d-1e4f9a7b3c5d")
    mint_id = str(_uuid.uuid5(_MINT_NS, "slug-SHAPE1"))
    fp = {"mint": mint_id, "nav": {"ua": "x"}}  # only 1 known dict key
    blob = base64.urlsafe_b64encode(json.dumps(fp).encode()).rstrip(b"=").decode()
    await repo.create_canary_token({
        "uuid": "tok-sh1", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-SHAPE1", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get(f"/c/slug-SHAPE1?d={blob}")
    triggers = await repo.list_canary_triggers("tok-sh1")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_invalid_shape"] == "1"
    assert "_fp" not in headers


@pytest.mark.asyncio
async def test_fp_invalid_mint_rejected(repo: SQLiteRepository, bus: FakeBus) -> None:
    """Wrong mint UUID in payload → ``_fp_invalid_mint=1``, no ``_fp``."""
    import base64
    import json

    fp = {
        "mint": "wrong-uuid-entirely",
        "nav": {"x": 1}, "scr": {"x": 1}, "tz": {"x": 1},
        "id": "a" * 64,
    }
    blob = base64.urlsafe_b64encode(json.dumps(fp).encode()).rstrip(b"=").decode()
    await repo.create_canary_token({
        "uuid": "tok-mint1", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-MINT1", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get(f"/c/slug-MINT1?d={blob}")
    triggers = await repo.list_canary_triggers("tok-mint1")
    headers = json.loads(triggers[0]["raw_headers"])
    assert headers["_fp_invalid_mint"] == "1"
    assert "_fp" not in headers


@pytest.mark.asyncio
async def test_fp_rate_limited_on_excess_submissions(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    """31st rapid-fire submission → ``_fp_rate_limited=1``, no ``_fp``."""
    import json
    import decnet.canary.worker as _worker

    # Reset the rate bucket so other tests don't bleed in.
    _worker._fp_rate_buckets.clear()

    blob, _ = _make_fp_blob("slug-RATE1")
    await repo.create_canary_token({
        "uuid": "tok-rate1", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-RATE1", "secret_seed": "s", "created_by": "u1",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        for _ in range(31):
            client.get(
                f"/c/slug-RATE1?d={blob}",
                headers={"X-Forwarded-For": "1.2.3.4"},
            )
    triggers = await repo.list_canary_triggers("tok-rate1")
    # list_canary_triggers orders DESC (newest first) — index 0 is the 31st hit.
    newest_headers = json.loads(triggers[0]["raw_headers"])
    assert newest_headers["_fp_rate_limited"] == "1"
    assert "_fp" not in newest_headers
    # Oldest (30th or earlier) should be clean.
    oldest_headers = json.loads(triggers[-1]["raw_headers"])
    assert "_fp_rate_limited" not in oldest_headers
    assert "_fp" in oldest_headers

    _worker._fp_rate_buckets.clear()


@pytest.mark.asyncio
async def test_fp_deregisters_slug_after_valid_hit(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    """After a valid fingerprint beacon the slug goes dark — second hit records nothing."""
    import json

    blob, _ = _make_fp_blob("slug-DEREG1")
    await repo.create_canary_token({
        "uuid": "tok-dereg1", "kind": "http", "decky_name": "web1",
        "generator": "fingerprint_html", "placement_path": "/x",
        "callback_token": "slug-DEREG1", "secret_seed": "s", "created_by": "u1",
        "fingerprint_nonce": "deadbeef01234567",
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        # First hit — valid FP, deregisters slug.
        client.get(f"/c/slug-DEREG1?d={blob}&k=deadbeef01234567")
        # Second hit — slug is revoked, stealth 200 but nothing persisted.
        client.get(f"/c/slug-DEREG1?d={blob}&k=deadbeef01234567")
    triggers = await repo.list_canary_triggers("tok-dereg1")
    assert len(triggers) == 1  # only the first hit landed


@pytest.mark.asyncio
async def test_plain_http_canary_not_deregistered(
    repo: SQLiteRepository, bus: FakeBus,
) -> None:
    """Plain HTTP canaries (no fingerprint_nonce) are NOT auto-revoked on a hit."""
    await repo.create_canary_token({
        "uuid": "tok-plain1", "kind": "http", "decky_name": "web1",
        "generator": "env_file", "placement_path": "/x",
        "callback_token": "slug-PLAIN1", "secret_seed": "s", "created_by": "u1",
        # fingerprint_nonce intentionally absent / NULL
    })
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        client.get("/c/slug-PLAIN1")
        client.get("/c/slug-PLAIN1")
    triggers = await repo.list_canary_triggers("tok-plain1")
    assert len(triggers) == 2  # both hits recorded — no deregistration
    tok = await repo.get_canary_token("tok-plain1")
    assert tok["state"] == "planted"


@pytest.mark.asyncio
async def test_no_decnet_strings_in_response(repo: SQLiteRepository, bus: FakeBus) -> None:
    """Stealth posture: nothing in the HTTP surface mentions DECNET."""
    app = _build_app(repo, bus)
    with TestClient(app) as client:
        resp = client.get("/c/anything")
        body = resp.content.lower()
        for v in resp.headers.values():
            assert b"decnet" not in v.lower().encode()
        assert b"decnet" not in body
        # Docs / openapi / redoc are disabled.
        assert client.get("/docs").status_code == 404
        assert client.get("/openapi.json").status_code == 404
        assert client.get("/redoc").status_code == 404