#!/usr/bin/env python3
"""Render every route in a real browser and check it actually works.

WHY THIS EXISTS
---------------
The unit suites have been green through defects that made the app unusable.
The sharpest example: `new THREE.WebGLRenderer()` throws on a device without
WebGL, the exception escaped its effect, and React unmounted the entire root
— every page a blank screen, no modes, no ask field, nothing. 432 frontend
tests passed the whole time, because jsdom never builds a WebGL context and
nothing exercised the real page in a real browser.

The same blind spot covers the layout bugs this project keeps hitting: a
panel that forces horizontal scroll on a phone, an input under 16px that
makes iOS zoom in and never back out, a page that renders nothing because a
component threw during mount. None of those are visible to a test that
renders one component into jsdom.

So this checks the four things that are cheap to verify, impossible to fake,
and have each actually gone wrong here:

  * the page RENDERS  — #root has children and the body has real text
  * no HORIZONTAL SCROLL — scrollWidth must not exceed the viewport
  * no INPUT below 16px — iOS zooms on focus below that and never zooms back
  * no UNCAUGHT JS ERROR during load

It drives Chrome over the DevTools Protocol directly, so it needs no test
framework and no npm dependency — just a Chrome running with
`--remote-debugging-port`.

USAGE
-----
    python3 scripts/smoke.py                       # phone width, live site
    python3 scripts/smoke.py --width 1440          # desktop width
    python3 scripts/smoke.py --base http://127.0.0.1:7777

Exits non-zero if any route fails, so it can gate a deploy.
"""

import argparse
import asyncio
import json
import sys
import urllib.request

try:
    import websockets
except ImportError:  # pragma: no cover - environment guidance, not logic
    sys.exit("needs `websockets` (backend/venv has it: backend/venv/bin/python scripts/smoke.py)")

# Every route in frontend/src/App.tsx that can be opened directly. Parameterised
# detail routes are covered by their index pages; `*` is the catch-all.
ROUTES = [
    "/", "/enter", "/seance", "/log", "/codex", "/shop", "/inventory",
    "/devices", "/doctrine", "/profile", "/hunters", "/messages", "/secret",
]

# How long to let a route settle before measuring. The séance opens a
# websocket, waits on the veil/conditions fetch and mounts a 3D scene, so it
# is materially slower than a static page — measuring too early reports a
# blank screen that is really just an unfinished one. That exact mistake cost
# a round of false alarms while writing this.
SETTLE_SECONDS = 9

PROBE = """
JSON.stringify({
  kids: document.getElementById('root')?.children.length ?? -1,
  text: (document.body.innerText || '').trim().length,
  scrollW: document.documentElement.scrollWidth,
  // documentElement.clientWidth, NOT window.innerWidth. Under Chrome's
  // mobile emulation innerWidth expands to the CONTENT width when a page
  // overflows (measured: 1200 on a 390px viewport), so comparing against it
  // yields 0 for every page and the check silently never fires. Caught by
  // pointing this script at a deliberately 1200px-wide page and watching it
  // report "ok" — clientWidth stays at the real 390.
  inner: document.documentElement.clientWidth,
  tiny: [...document.querySelectorAll('input,textarea')]
          .filter(e => parseFloat(getComputedStyle(e).fontSize) < 16)
          .map(e => e.className || e.type || 'input')
})
"""


def cdp(endpoint: str, path: str, method: str = "GET") -> dict:
    # Chrome 149 requires PUT for /json/new and answers GET with 405.
    req = urllib.request.Request(endpoint + path, method=method)
    body = urllib.request.urlopen(req, timeout=10).read()
    return json.loads(body) if body.strip().startswith(b"{") else {}


async def check(endpoint: str, base: str, path: str, width: int, height: int) -> dict:
    target = cdp(endpoint, "/json/new?about:blank", method="PUT")
    errors: list[str] = []
    counter = 0
    try:
        async with websockets.connect(target["webSocketDebuggerUrl"], max_size=40_000_000) as ws:
            async def cmd(method: str, params: dict | None = None) -> dict:
                nonlocal counter
                counter += 1
                await ws.send(json.dumps({"id": counter, "method": method, "params": params or {}}))
                while True:
                    msg = json.loads(await ws.recv())
                    if msg.get("method") == "Runtime.exceptionThrown":
                        errors.append(str(msg["params"]["exceptionDetails"].get("text", ""))[:160])
                    if msg.get("id") == counter:
                        return msg.get("result", {})

            await cmd("Emulation.setDeviceMetricsOverride", {
                "width": width, "height": height,
                "deviceScaleFactor": 2, "mobile": width < 800,
            })
            await cmd("Runtime.enable")
            await cmd("Page.enable")
            await cmd("Page.navigate", {"url": base + path})
            await asyncio.sleep(SETTLE_SECONDS)
            result = await cmd("Runtime.evaluate", {"expression": PROBE, "returnByValue": True})
            data = json.loads(result["result"]["value"])
    finally:
        cdp(endpoint, f"/json/close/{target['id']}")

    # A scrollWidth SMALLER than the viewport is normal (that is the
    # scrollbar); only an excess is a horizontal-scroll bug.
    overflow = max(0, data["scrollW"] - data["inner"])
    problems = []
    if data["kids"] <= 0 or data["text"] < 20:
        problems.append("BLANK")
    if overflow:
        problems.append(f"H-SCROLL +{overflow}px")
    if data["tiny"]:
        problems.append(f"INPUT<16px ({', '.join(data['tiny'][:3])})")
    if errors:
        problems.append(f"JS-ERROR {errors[0]}")
    return {"path": path, "overflow": overflow, "problems": problems, **data}


async def main() -> int:
    ap = argparse.ArgumentParser()
    ap.add_argument("--base", default="https://spirit.thetempleofdoom.com")
    ap.add_argument("--endpoint", default="http://127.0.0.1:9222", help="Chrome DevTools endpoint")
    ap.add_argument("--width", type=int, default=390)
    ap.add_argument("--height", type=int, default=844)
    args = ap.parse_args()

    try:
        cdp(args.endpoint, "/json/version")
    except Exception as exc:
        sys.exit(
            f"no Chrome at {args.endpoint} ({exc}).\n"
            "start one with: chrome --headless --remote-debugging-port=9222"
        )

    print(f"{args.base} @ {args.width}x{args.height}\n")
    print(f"{'route':<12} {'kids':>4} {'text':>6}  status")
    failed = []
    for path in ROUTES:
        r = await check(args.endpoint, args.base, path, args.width, args.height)
        status = "ok" if not r["problems"] else " · ".join(r["problems"])
        print(f"{path:<12} {r['kids']:>4} {r['text']:>6}  {status}")
        if r["problems"]:
            failed.append(r)

    if failed:
        print(f"\n{len(failed)} route(s) failed:")
        for r in failed:
            print(f"  {r['path']}: {' · '.join(r['problems'])}")
        return 1
    print(f"\nall {len(ROUTES)} routes render, no horizontal scroll, "
          "no sub-16px inputs, no uncaught errors")
    return 0


if __name__ == "__main__":
    raise SystemExit(asyncio.run(main()))