#!/usr/bin/env python3
"""chat-state-check.py — one-shot CDP chat-state probe for a single node.

Runs INSIDE the node's netns (CDP listens on 127.0.0.1 there).

Usage: chat-state-check.py <cdp_port> <mode> [name]
  modes: main | list | sidechat <name>

Prints one JSON object to stdout.

Honest limits (see CHATSTATE_SPEC.md): only the DOM-visible message window
is captured (React virtualization); author attribution is best-effort and
may be null; checked_at is the report time, not per-message times.
"""
import base64
import json
import sys
import time
import urllib.request

import websocket

MSG_N = 10
MSG_WIDTH = 500


def connect(port):
    with urllib.request.urlopen(
            "http://127.0.0.1:%s/json/list" % port, timeout=5) as r:
        targets = json.load(r)
    pages = [t for t in targets if t.get("type") == "page"]
    if not pages:
        return None
    return websocket.create_connection(
        pages[0]["webSocketDebuggerUrl"], timeout=15)


def ev1(ws, expr, await_p=False, reads=30):
    """Runtime.evaluate that skips CDP event chatter while awaiting ours."""
    ws.send(json.dumps({
        "id": 1, "method": "Runtime.evaluate",
        "params": {"expression": expr, "returnByValue": True,
                   "awaitPromise": await_p}}))
    for _ in range(reads):
        resp = json.loads(ws.recv())
        if resp.get("id") != 1:
            continue
        if "error" in resp:
            raise RuntimeError("CDP evaluate failed: %s" % resp["error"])
        res = resp.get("result", {}).get("result", {})
        return res.get("value")
    raise RuntimeError("CDP evaluate: no response")


def read_current(ws):
    title = ev1(ws, "document.title") or ""
    url = ev1(ws, "window.location.href") or ""
    msgs = ev1(ws, """(() => {
      const ps = [...document.querySelectorAll('p')].slice(-%d)
        .map(p => (p.innerText||'').slice(0,%d)).filter(t => t.trim());
      return ps;
    })()""" % (MSG_N, MSG_WIDTH)) or []
    return {"title": title, "url": url,
            "messages": [{"text": t} for t in msgs]}


def _wait_for(ws, expr, timeout_s=12):
    """Poll a JS truthiness expression until true or timeout."""
    deadline = time.time() + timeout_s
    while time.time() < deadline:
        try:
            if ev1(ws, expr):
                return True
        except Exception:  # noqa: BLE001
            pass
        time.sleep(1)
    return False


def ensure_sidebar_open(ws):
    """The toggle closes an open sidebar — only click when closed.

    Detected structurally via the 'New side chat' button (text matching
    'Side chats' is unreliable: main-chat messages can contain the phrase).
    Waits for React to render the panel after opening.
    """
    is_open = ev1(ws, """(() => {
      return !!document.querySelector('button[aria-label="New side chat"]');
    })()""")
    if not is_open:
        ev1(ws, """(() => {
          const btn = [...document.querySelectorAll('button')].find(b =>
            (b.textContent||'').includes('Open chat and side chats'));
          if (btn) btn.click();
        })()""")
        _wait_for(ws, """(() => {
          return !!document.querySelector(
            'button[aria-label="New side chat"]');
        })()""")
    # The row list renders a beat after the panel; wait for it.
    _wait_for(ws, """(() => {
      return document.querySelectorAll(
        'button[aria-label="More thread actions"]').length > 0;
    })()""", timeout_s=10)


_SIDEBAR_JS = """(() => {
  const anchor = document.querySelector('button[aria-label="New side chat"]');
  if (!anchor) return 'NOANCHOR';
  let sec = anchor.parentElement;
  for (let i = 0; i < 8 && sec; i++) {
    if (sec.querySelectorAll(
        'button[aria-label="More thread actions"]').length) break;
    sec = sec.parentElement;
  }
  if (!sec) return 'NOSEC';
  return JSON.stringify({ok: true});
})()"""


def _sidebar_section(ws):
    """Return True when the side-chat list section is addressable."""
    raw = ev1(ws, _SIDEBAR_JS)
    try:
        return json.loads(raw or "").get("ok", False)
    except (ValueError, TypeError):
        return False


_LIST_JS = """(() => {
  const T = (el) => (el.innerText || '').trim();
  const TS =
    /^(\\d+[smhd]|just now|Yesterday|Today|[A-Z][a-z]{2} \\d{1,2}.*)$/;
  const Y = (el) => el.getBoundingClientRect().top;
  const h3s = [...document.querySelectorAll('h3')];
  const head = h3s.find(h => h.textContent.trim() === 'Side chats');
  if (!head) return '[]';
  // Scroll the list to top so the section's rows sit above the next
  // (sticky) header; without this, rows below the fold are missed.
  let sc = head.parentElement;
  for (let i = 0; i < 8 && sc; i++) {
    if (sc.scrollHeight > sc.clientHeight + 10) break;
    sc = sc.parentElement;
  }
  if (sc) sc.scrollTop = 0;
  const y0 = Y(head);
  const isStopText = (t) => t === 'Unread updates' || t === 'Chats' ||
    t === 'Unread chats';
  let stopY = null;
  for (const h of h3s) {
    const y = Y(h);
    if (y > y0 + 5 && (stopY === null || y < stopY)) stopY = y;
  }
  // Non-H3 section headers ("Unread updates", ...) also bound the list.
  for (const el of document.querySelectorAll('*')) {
    if (el.children.length !== 0) continue;
    if (!isStopText((el.textContent || '').trim())) continue;
    const y = Y(el);
    if (y > y0 + 5 && (stopY === null || y < stopY)) stopY = y;
  }
  const names = [];
  for (const el of document.querySelectorAll('div')) {
    const cn = (el.className || '').toString();
    if (cn.indexOf('nav-row') === -1) continue;
    const y = Y(el);
    if (y <= y0 + 5) continue;
    if (stopY !== null && y >= stopY - 5) continue;
    const m = T(el).match(/^([^\\n]+)\\n\\n(.+)$/);
    if (m && TS.test(m[2].trim()) && names.indexOf(m[1].trim()) === -1) {
      names.push(m[1].trim());
      if (names.length >= 8) break;
    }
  }
  return JSON.stringify(names);
})()"""


def _list_once(ws):
    raw = ev1(ws, _LIST_JS)
    try:
        return json.loads(raw or "[]")
    except (ValueError, TypeError):
        return []


def list_sidechats(ws):
    ensure_sidebar_open(ws)
    if not _sidebar_section(ws):
        return []
    # React renders rows progressively after navigation; poll until the
    # list stabilizes instead of trusting the first paint.
    prev = None
    for _ in range(4):
        names = _list_once(ws)
        if names and names == prev:
            return names
        prev = names
        time.sleep(2)
    return prev or []


def open_sidechat(ws, name):
    """Open the side chat by clicking its row div inside the sidebar section.

    Clicking the row (not a text search over the whole document) avoids
    hitting message text that happens to contain the chat name.
    """
    ensure_sidebar_open(ws)
    b64 = base64.b64encode(name.encode()).decode()
    return ev1(ws, """(async () => {
      const nm = atob('%s');
      const T = (el) => (el.innerText || '').trim();
      const target = [...document.querySelectorAll('div')].find(el => {
        const cn = (el.className || '').toString();
        if (cn.indexOf('nav-row') === -1) return false;
        const m = T(el).match(/^([^\\n]+)\\n\\n(.+)$/);
        return m && m[1].trim() === nm;
      });
      if (!target) return 'NOTFOUND';
      target.click();
      await new Promise(r => setTimeout(r, 4000));
      const href = window.location.href;
      if (href.indexOf('/thread/') === -1) return 'NOTFOUND';
      return href;
    })()""" % b64, await_p=True)


def navigate_main(ws):
    ws.send(json.dumps({"id": 2, "method": "Page.navigate",
                        "params": {"url": "https://muse.ai/"}}))
    for _ in range(20):
        resp = json.loads(ws.recv())
        if resp.get("id") == 2:
            break
    time.sleep(6)


def main():
    if len(sys.argv) < 3:
        print(json.dumps({"ok": False, "error": "usage"}))
        sys.exit(1)
    port, mode = sys.argv[1], sys.argv[2]
    name = sys.argv[3] if len(sys.argv) > 3 else ""
    try:
        ws = connect(port)
    except Exception as e:  # noqa: BLE001
        print(json.dumps({"ok": False, "error": "cdp_connect_failed",
                          "detail": str(e)[:120]}))
        return
    if ws is None:
        print(json.dumps({"ok": False, "error": "no_page"}))
        return
    try:
        if mode == "list":
            print(json.dumps({"ok": True,
                              "sidechats": list_sidechats(ws)}))
        elif mode == "sidechat":
            href = open_sidechat(ws, name)
            if href == "NOTFOUND":
                print(json.dumps({"ok": False, "error": "sidechat_not_found",
                                  "name": name}))
            else:
                cur = read_current(ws)
                cur.update({"ok": True, "context": "sidechat", "name": name})
                print(json.dumps(cur))
        else:
            navigate_main(ws)
            cur = read_current(ws)
            cur.update({"ok": True, "context": "main", "name": "Main chat"})
            print(json.dumps(cur))
    except Exception as e:  # noqa: BLE001
        print(json.dumps({"ok": False, "error": "probe_failed",
                          "detail": str(e)[:200]}))
    finally:
        try:
            ws.close()
        except Exception:  # noqa: BLE001
            pass


main()