"""Section 6.3 — Static asset caching and compression tests.

Covers:
- StaticCacheMiddleware injects correct Cache-Control headers
- Vendor JS files include ?v= query strings in base.html
- static_version is a non-empty 8-char hex string (content hash)
- Blocking sync I/O in objects.py is wrapped in asyncio.to_thread
- nginx gzip config present in nginx-cf.conf
"""
from __future__ import annotations

import hashlib
import inspect
import re
import ast
from pathlib import Path

import pytest
from musehub.muse_contracts.json_types import JSONObject


# ── paths ─────────────────────────────────────────────────────────────────────
_REPO = Path(__file__).resolve().parents[1]
_STATIC_DIR = _REPO / "musehub" / "templates" / "musehub" / "static"
_MIDDLEWARE = _REPO / "musehub" / "middleware" / "static_cache.py"
_TEMPLATES_PY = _REPO / "musehub" / "api" / "routes" / "musehub" / "_templates.py"
_BASE_HTML = _REPO / "musehub" / "templates" / "musehub" / "base.html"
_OBJECTS_PY = _REPO / "musehub" / "api" / "routes" / "musehub" / "objects.py"
_NGINX_CONF = _REPO / "deploy" / "nginx-cf.conf"
_MAIN_PY = _REPO / "musehub" / "main.py"


# ── StaticCacheMiddleware unit tests ──────────────────────────────────────────

class TestStaticCacheMiddleware:
    """Unit-test the pure ASGI middleware without spinning up FastAPI."""

    def _make_scope(self, path: str) -> JSONObject:
        return {"type": "http", "path": path, "method": "GET", "headers": []}

    async def _run(self, path: str) -> list[dict]:
        from musehub.middleware.static_cache import StaticCacheMiddleware

        messages: list[dict] = []

        async def _app(scope, receive, send):
            await send({
                "type": "http.response.start",
                "status": 200,
                "headers": [],
            })
            await send({"type": "http.response.body", "body": b"", "more_body": False})

        async def _capture(msg):
            messages.append(msg)

        async def _noop_receive():
            return {}

        mw = StaticCacheMiddleware(_app)
        await mw(self._make_scope(path), _noop_receive, _capture)
        return messages

    @pytest.mark.asyncio
    async def test_css_gets_far_future_cache(self):
        # ASGI scope["path"] never includes query string
        msgs = await self._run("/static/app.css")
        start = next(m for m in msgs if m["type"] == "http.response.start")
        headers = dict(start["headers"])
        assert headers[b"cache-control"] == b"public, max-age=31536000, immutable"

    @pytest.mark.asyncio
    async def test_js_gets_far_future_cache(self):
        msgs = await self._run("/static/app.js")
        start = next(m for m in msgs if m["type"] == "http.response.start")
        headers = dict(start["headers"])
        assert headers[b"cache-control"] == b"public, max-age=31536000, immutable"

    @pytest.mark.asyncio
    async def test_map_gets_far_future_cache(self):
        msgs = await self._run("/static/app.js.map")
        start = next(m for m in msgs if m["type"] == "http.response.start")
        headers = dict(start["headers"])
        assert headers[b"cache-control"] == b"public, max-age=31536000, immutable"

    @pytest.mark.asyncio
    async def test_favicon_gets_one_day_cache(self):
        msgs = await self._run("/static/favicon.svg")
        start = next(m for m in msgs if m["type"] == "http.response.start")
        headers = dict(start["headers"])
        assert headers[b"cache-control"] == b"public, max-age=86400"

    @pytest.mark.asyncio
    async def test_png_gets_one_day_cache(self):
        msgs = await self._run("/static/favicon-32.png")
        start = next(m for m in msgs if m["type"] == "http.response.start")
        headers = dict(start["headers"])
        assert headers[b"cache-control"] == b"public, max-age=86400"

    @pytest.mark.asyncio
    async def test_non_static_path_passes_through_unmodified(self):
        msgs = await self._run("/repos/abc/tree/main")
        start = next(m for m in msgs if m["type"] == "http.response.start")
        headers = dict(start["headers"])
        assert b"cache-control" not in headers

    @pytest.mark.asyncio
    async def test_existing_cache_control_not_overwritten(self):
        """If app already set Cache-Control, middleware must leave it alone."""
        from musehub.middleware.static_cache import StaticCacheMiddleware

        messages: list[dict] = []

        async def _app_with_cc(scope, receive, send):
            await send({
                "type": "http.response.start",
                "status": 200,
                "headers": [(b"cache-control", b"no-store")],
            })
            await send({"type": "http.response.body", "body": b""})

        async def _capture(msg):
            messages.append(msg)

        async def _noop_receive():
            return {}

        mw = StaticCacheMiddleware(_app_with_cc)
        await mw(self._make_scope("/static/app.css"), _noop_receive, _capture)

        start = next(m for m in messages if m["type"] == "http.response.start")
        cc_values = [v for k, v in start["headers"] if k == b"cache-control"]
        # exactly one value and it is the app's, not ours
        assert cc_values == [b"no-store"]

    @pytest.mark.asyncio
    async def test_websocket_scope_passes_through(self):
        """Non-HTTP scope must not be touched."""
        from musehub.middleware.static_cache import StaticCacheMiddleware

        called = []

        async def _app(scope, receive, send):
            called.append(scope["type"])

        async def _noop_receive():
            return {}

        async def _noop_send(msg):
            pass

        mw = StaticCacheMiddleware(_app)
        await mw({"type": "websocket", "path": "/static/app.css"}, _noop_receive, _noop_send)
        assert called == ["websocket"]


# ── base.html vendor versioning ───────────────────────────────────────────────

class TestBaseHtmlVersioning:
    _src = _BASE_HTML.read_text()

    def test_alpinejs_has_version_param(self):
        assert re.search(r"alpinejs\.min\.js\?v=\{\{", self._src)

    def test_htmx_has_version_param(self):
        assert re.search(r"htmx\.min\.js\?v=\{\{", self._src)

    def test_json_enc_has_version_param(self):
        assert re.search(r"json-enc\.js\?v=\{\{", self._src)

    def test_response_targets_has_version_param(self):
        assert re.search(r"response-targets\.js\?v=\{\{", self._src)

    def test_app_css_has_version_param(self):
        assert re.search(r"app\.css\?v=\{\{", self._src)

    def test_app_js_has_version_param(self):
        assert re.search(r"app\.js\?v=\{\{", self._src)


# ── static_version content hash ───────────────────────────────────────────────

class TestStaticVersion:
    def test_static_version_is_8_hex_chars_when_assets_exist(self, tmp_path):
        """_compute_static_version returns 8 lowercase hex chars when CSS+JS present."""
        css = tmp_path / "app.css"
        js = tmp_path / "app.js"
        css.write_bytes(b"body{color:red}")
        js.write_bytes(b"console.log(1)")

        import hashlib
        h = hashlib.sha256()
        h.update(css.read_bytes())
        h.update(js.read_bytes())
        expected = h.hexdigest()[:8]

        # Not the empty-input sentinel
        assert expected != "e3b0c442"
        assert re.fullmatch(r"[0-9a-f]{8}", expected)

    def test_static_version_falls_back_to_cache_id_when_assets_missing(self, tmp_path, monkeypatch):
        """When app.css and app.js are absent, falls back to .cache-id."""
        import importlib
        import musehub.api.routes.musehub._templates as tpl_mod

        # Patch the static dir to tmp_path (no CSS/JS)
        cache_id = tmp_path / ".cache-id"
        cache_id.write_text("cafebabe")

        monkeypatch.setattr(tpl_mod, "_STATIC_DIR", tmp_path)
        monkeypatch.setattr(tpl_mod, "_cache_id_path", cache_id)

        result = tpl_mod._compute_static_version()
        assert result == "cafebabe"

    def test_static_version_empty_when_nothing_available(self, tmp_path, monkeypatch):
        import musehub.api.routes.musehub._templates as tpl_mod

        monkeypatch.setattr(tpl_mod, "_STATIC_DIR", tmp_path)
        monkeypatch.setattr(tpl_mod, "_cache_id_path", tmp_path / ".cache-id")

        result = tpl_mod._compute_static_version()
        assert result == ""


# ── objects.py: no blocking sync I/O ─────────────────────────────────────────

class TestObjectsNoBlockingIO:
    _src = _OBJECTS_PY.read_text()

    def test_asyncio_imported(self):
        assert "import asyncio" in self._src

    def test_open_wrapped_in_to_thread(self):
        """Any open() call inside an async function must be inside asyncio.to_thread."""
        # Check that asyncio.to_thread appears and a bare open() call outside a nested
        # def/lambda does not appear as a direct await.
        assert "asyncio.to_thread" in self._src

    def test_no_bare_open_in_async_handler(self):
        """
        Parse the AST to ensure no `open(...)` call appears as a direct statement
        (not inside a nested sync function) within an async function body.
        """
        tree = ast.parse(self._src)

        violations: list[int] = []

        class _Visitor(ast.NodeVisitor):
            def __init__(self):
                self._in_async = 0
                self._in_sync_nested = 0

            def visit_AsyncFunctionDef(self, node):
                self._in_async += 1
                self.generic_visit(node)
                self._in_async -= 1

            def visit_FunctionDef(self, node):
                if self._in_async > 0:
                    self._in_sync_nested += 1
                    self.generic_visit(node)
                    self._in_sync_nested -= 1
                else:
                    self.generic_visit(node)

            def visit_Call(self, node):
                if (
                    self._in_async > 0
                    and self._in_sync_nested == 0
                    and isinstance(node.func, ast.Name)
                    and node.func.id == "open"
                ):
                    violations.append(node.lineno)
                self.generic_visit(node)

        _Visitor().visit(tree)
        assert violations == [], f"Bare open() in async handler at lines {violations}"


# ── nginx gzip config ─────────────────────────────────────────────────────────

class TestNginxGzip:
    _src = _NGINX_CONF.read_text()

    def test_gzip_on(self):
        assert re.search(r"^\s*gzip\s+on\s*;", self._src, re.MULTILINE)

    def test_gzip_comp_level(self):
        assert re.search(r"gzip_comp_level\s+[1-9]", self._src)

    def test_gzip_types_includes_css(self):
        assert "text/css" in self._src

    def test_gzip_types_includes_js(self):
        assert re.search(r"(text/javascript|application/javascript)", self._src)

    def test_gzip_types_includes_json(self):
        assert "application/json" in self._src

    def test_gzip_vary_on(self):
        assert re.search(r"gzip_vary\s+on\s*;", self._src)


# ── StaticCacheMiddleware registered in main.py ───────────────────────────────

class TestMiddlewareRegistration:
    _src = _MAIN_PY.read_text()

    def test_static_cache_middleware_imported(self):
        assert "StaticCacheMiddleware" in self._src

    def test_static_cache_middleware_added(self):
        assert "add_middleware(StaticCacheMiddleware)" in self._src