import gzip
import re
import shutil
from pathlib import Path

import httpx
import pytest

from src import main
from src.frontend_bundle import build_frontend
from src.views import dashboard, runtime_bundle, service_worker


FRONTEND = Path(__file__).resolve().parents[1] / "frontend"
PAGE_SCRIPT = re.compile(r'<script src="(static/[^"]+\.js)"></script>')


def test_page_runtime_is_one_deterministic_content_addressed_bundle(tmp_path):
    first = build_frontend(FRONTEND)
    second = build_frontend(FRONTEND)

    assert first.runtime_name == second.runtime_name
    assert first.runtime_bytes == second.runtime_bytes
    assert PAGE_SCRIPT.findall(first.dashboard_html) == []
    assert first.dashboard_html.count("<script src=") == 1
    assert f'<script src="{first.runtime_name}"></script>' in first.dashboard_html
    assert first.runtime_name.startswith("runtime-")
    assert first.runtime_name.endswith(".js")
    assert len(gzip.compress(first.runtime_bytes, mtime=0)) <= 100 * 1024

    changed_frontend = tmp_path / "frontend"
    shutil.copytree(FRONTEND, changed_frontend)
    (changed_frontend / "widgets.js").write_text(
        (changed_frontend / "widgets.js").read_text() + "\n// changed\n"
    )

    changed = build_frontend(changed_frontend)
    assert changed.runtime_name != first.runtime_name
    assert changed.runtime_bytes != first.runtime_bytes


@pytest.mark.anyio
async def test_runtime_is_transferred_as_gzip_when_the_client_accepts_it():
    transport = httpx.ASGITransport(app=main.app)

    async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
        response = await client.get(
            f"/{main.FRONTEND_BUILD.runtime_name}",
            headers={"Accept-Encoding": "gzip"},
        )

    assert response.status_code == 200
    assert response.headers["content-encoding"] == "gzip"
    assert response.headers["vary"] == "Accept-Encoding"
    assert int(response.headers["content-length"]) <= 100 * 1024
    assert response.content == main.FRONTEND_BUILD.runtime_bytes
    assert response.headers["cache-control"] == "public, max-age=31536000, immutable"


@pytest.mark.anyio
@pytest.mark.parametrize("accept_encoding", ["identity", "gzip;q=0, identity;q=1"])
async def test_runtime_stays_unencoded_when_the_client_declines_gzip(accept_encoding):
    transport = httpx.ASGITransport(app=main.app)

    async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
        response = await client.get(
            f"/{main.FRONTEND_BUILD.runtime_name}",
            headers={"Accept-Encoding": accept_encoding},
        )

    assert response.status_code == 200
    assert "content-encoding" not in response.headers
    assert int(response.headers["content-length"]) == len(main.FRONTEND_BUILD.runtime_bytes)
    assert response.content == main.FRONTEND_BUILD.runtime_bytes


@pytest.mark.anyio
async def test_dashboard_shell_is_compressed_without_losing_response_policies():
    transport = httpx.ASGITransport(app=main.app)

    async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
        page = await client.get("/", headers={"Accept-Encoding": "gzip"})
        stylesheet = await client.get(
            "/static/dashboard.css", headers={"Accept-Encoding": "gzip"}
        )
        health = await client.get("/healthz", headers={"Accept-Encoding": "gzip"})

    assert page.headers["content-encoding"] == "gzip"
    assert page.headers["cache-control"] == "no-cache"
    assert page.headers["content-security-policy"]
    assert main.FRONTEND_BUILD.runtime_name in page.text
    assert stylesheet.headers["content-encoding"] == "gzip"
    assert "mobile-task-dock" in stylesheet.text
    assert health.json() == {"service": "stackchain-dashboard", "status": "ok"}
    assert "content-encoding" not in health.headers


def test_offline_shell_precaches_exact_runtime_without_superseded_page_modules():
    build = build_frontend(FRONTEND)

    assert f"BASE + '{build.runtime_name}'" in build.service_worker_source
    for source in build.page_sources:
        if source == "static/background-issue-sync.js":
            continue
        assert f"BASE + '{source}'" not in build.service_worker_source


@pytest.mark.anyio
async def test_runtime_asset_is_immutable_while_html_and_worker_revalidate():
    build = build_frontend(FRONTEND)

    html = await dashboard()
    bundle = await runtime_bundle(build.runtime_digest)
    worker = await service_worker()

    assert build.runtime_name in html
    assert bundle.body == build.runtime_bytes
    assert bundle.headers["cache-control"] == "public, max-age=31536000, immutable"
    assert worker.headers["cache-control"] == "no-cache"
    assert build.runtime_name.encode() in worker.body