"""Post-update maintenance for ``hermes update``: pre-update backup snapshot, state-db verify/restore, curator/FTS notices, FHS path guard, completion summary, stale-module purge.

Split out of ``update_cmd.py``, which re-imports every name so ``hermes_cli.update_cmd.<name>``
still resolves/monkeypatches. Origin helpers are imported lazily per function (no cycle;
test patches on ``update_cmd`` stay effective).
"""

import logging
from contextlib import suppress
import os
import shutil
import subprocess
import sys
import time as _time
from pathlib import Path
from typing import Optional
from hermes_constants import venv_python_path

from hermes_cli.update_cmd_common import _best_effort

# Log-record parity with the origin module.
logger = logging.getLogger("hermes_cli.update_cmd")


_UPDATE_RUNTIME_RELOAD_MODULES = "hermes_constants", "tools.environments.local", "tools.lazy_deps"


#: Package prefixes whose cached modules go stale when the checkout changes under this
#: process; purged (not reloaded) so any LATER import chain resolves against fresh source.
_STALE_PURGE_PREFIXES = "hermes_cli", "gateway", "tools", "tui_gateway", "agent"


#: Modules EXECUTING the update survive the purge: evicting them buys nothing (running frames
#: keep them alive) and reloading them mid-flight is the one genuinely unsafe move.
_STALE_PURGE_PROTECTED = frozenset(
    {
        "hermes_cli",
        "hermes_cli.main",
        "hermes_cli.update_cmd",
        "hermes_cli.hermes_logging",
    }
    # The updater's own split modules are executing too.
    | {f"hermes_cli.update_cmd_{c}" for c in (
        "config", "deps", "fleet", "git", "maint", "stash", "windows", "zip",
    )}
)


def _purge_stale_hermes_modules() -> None:
    """Evict every cached Hermes module after the checkout changed in-place. Never raises.

    The update runs in the pre-pull process; later phases lazily import NEW source into an OLD
    ``sys.modules`` world and die when new code references a symbol missing from a cached
    module. Purging (unlike reload) only drops the ``sys.modules`` entry — running frames keep
    their module objects — so later imports rebuild a self-consistent graph from the new tree.
    """
    from hermes_cli.update_cmd import _m
    with _best_effort('Could not purge stale Hermes modules: %s'):
        import importlib

        importlib.invalidate_caches()
        purged = []
        for name in list(_m().sys.modules):
            if name in _STALE_PURGE_PROTECTED:
                continue
            if not name.startswith(_STALE_PURGE_PREFIXES):
                continue
            root = name.split(".", 1)[0]
            if root not in _STALE_PURGE_PREFIXES:
                # startswith() also matches unrelated packages like ``gateway_foo``.
                continue
            if _m().sys.modules.pop(name, None) is not None:
                purged.append(name)
        if purged:
            logger.debug("Purged %d stale Hermes module(s) after checkout update", len(purged))


def _reload_updated_runtime_modules() -> None:
    """Reload the modules used by lazy-backend refresh: the pre-pull process's cached modules
    can expose old symbols despite new source on disk."""
    from hermes_cli.update_cmd import _m
    with _best_effort('Could not refresh update runtime modules: %s'):
        import importlib

        importlib.invalidate_caches()
        for module_name in _UPDATE_RUNTIME_RELOAD_MODULES:
            module = _m().sys.modules.get(module_name)
            if module is None:
                continue
            try:
                importlib.reload(module)
            except Exception as exc:
                logger.debug("Could not reload updated module %s: %s", module_name, exc)


def _print_curator_first_run_notice() -> None:
    """Curator heads-up after update. Fires only when enabled AND never run — the window where
    the first pass (deferred one ``interval_hours``) is pending, so the user can preview or
    disable it first. Silent on steady state."""
    try:
        from agent import curator
    except Exception:
        return
    try:
        if not curator.is_enabled():
            return
        state = curator.load_state()
    except Exception:
        return
    if state.get("last_run_at"):
        return
    try:
        hours = curator.get_interval_hours()
    except Exception:
        hours = 24 * 7
    days = max(1, hours // 24)
    print()
    print("ℹ Skill curator")
    print(
        f"  Background skill maintenance is enabled. First pass is deferred "
        f"~{days}d after installation; only agent-created skills are in "
        f"scope and nothing is ever auto-deleted (archive is recoverable)."
    )
    print("  Preview now:  hermes curator run --dry-run")
    print("  Pause it:     hermes curator pause")
    print("  Docs:         https://hermes-agent.nousresearch.com/docs/user-guide/features/curator")


def _print_fts_optimize_available_notice() -> None:
    """Advertise the opt-in v23 FTS optimization when state.db is still on the legacy layout.

    ``sessions.fts_optimize_notice``: ``advise`` (default), ``require`` (firmer), ``off``.
    """
    mode = "advise"
    try:
        from hermes_cli.config import load_config

        mode = str(
            ((load_config() or {}).get("sessions") or {}).get(
                "fts_optimize_notice", "advise"
            )
        ).strip().lower()
    except Exception:
        mode = "advise"
    if mode == "off":
        return

    try:
        from hermes_constants import get_hermes_home
        from hermes_state import SessionDB
    except Exception:
        return
    db_path = get_hermes_home() / "state.db"
    if not db_path.exists():
        return
    try:
        size_gb = db_path.stat().st_size / (1024 ** 3)
    except OSError:
        return
    # Small DBs: the win isn't worth the nag.
    if size_gb < 0.5:
        return
    db = None
    interrupted = False
    try:
        db = SessionDB(db_path=db_path, read_only=True)
        # read_only opens skip schema init; probe the layout directly.
        row = db._conn.execute(
            "SELECT sql FROM sqlite_master "
            "WHERE type = 'table' AND name = 'messages_fts'"
        ).fetchone()
        # Interrupted optimize-storage: v23 table shape but backfill markers / trash
        # tables remain. Re-running resumes it, so offer the command again.
        interrupted = bool(
            db._conn.execute(
                "SELECT 1 FROM state_meta "
                "WHERE key = 'fts_rebuild_high_water' LIMIT 1"
            ).fetchone()
            or db._conn.execute(
                "SELECT 1 FROM sqlite_master WHERE type = 'table' "
                "AND name LIKE 'fts\\_v22\\_trash\\_%' ESCAPE '\\' LIMIT 1"
            ).fetchone()
            or db._conn.execute(
                "SELECT 1 FROM state_meta WHERE key IN "
                "('fts_cjk_rebuild_high_water', 'fts_cjk_stale') LIMIT 1"
            ).fetchone()
        )
    except Exception:
        return
    finally:
        if db is not None:
            with suppress(Exception):
                db.close()
    sql = (row[0] if row else "") or ""
    if not sql or ("tool_name" in sql and not interrupted):
        return

    if interrupted:
        print()
        print("◆ Session database optimization incomplete")
        print(
            "  A previous `hermes sessions optimize-storage` run was "
            "interrupted. Search still works; re-run the command to resume "
            "and finish reclaiming disk:"
        )
        print("    hermes sessions optimize-storage")
        return

    est_reclaim = size_gb * 0.6
    print()
    if mode == "require":
        print("◆ Session database upgrade required")
        print(
            f"  Your search index uses the OLD storage layout and should be "
            f"upgraded. The new layout typically frees ~60% of state.db "
            f"(≈{est_reclaim:.1f} GB of your current {size_gb:.1f} GB) and is "
            f"required for continued optimal operation."
        )
    else:
        print("◆ Reclaim ~60% of your session database disk")
        print(
            f"  Your search index uses the old storage layout. Upgrading it "
            f"typically frees ~60% of state.db — about {est_reclaim:.1f} GB "
            f"of your current {size_gb:.1f} GB."
        )
    print("  Run when convenient:  hermes sessions optimize-storage")
    print(
        "  It runs in the foreground with a progress bar, is safe to "
        "interrupt/re-run, and never changes your conversations."
    )


def _print_curator_recent_run_notice() -> None:
    """Print the latest background curator run summary (rename map) once, stamping
    ``last_run_summary_shown_at``. Silent when never run, already shown, or no rename info."""
    try:
        from agent import curator
    except Exception:
        return
    try:
        state = curator.load_state()
    except Exception:
        return

    last_run_at = state.get("last_run_at")
    if not last_run_at:
        return  # no curator run yet — first-run notice handles this case

    if state.get("last_run_summary_shown_at") == last_run_at:
        return  # already shown for this run

    summary = state.get("last_run_summary") or ""
    if not summary:
        return

    # Only a multi-line summary (rename map) is worth showing; still stamp it shown.
    if "\n" not in summary:
        with suppress(Exception):
            state["last_run_summary_shown_at"] = last_run_at
            curator.save_state(state)
        return

    when = _format_time_ago(last_run_at)
    print()
    print(f"ℹ Skill curator — last run {when}")
    for line in summary.splitlines():
        print(f"  {line}")
    print("  (This message shows once per curator run. View anytime: hermes curator status)")

    with suppress(Exception):
        state["last_run_summary_shown_at"] = last_run_at
        curator.save_state(state)


def _format_time_ago(iso_ts: str) -> str:
    """Render an ISO timestamp as `Xh ago` / `Xd ago` / `Xm ago`. Best effort."""
    try:
        from datetime import datetime, timezone
        ts = datetime.fromisoformat(iso_ts.replace("Z", "+00:00"))
        if ts.tzinfo is None:
            ts = ts.replace(tzinfo=timezone.utc)
        delta = datetime.now(timezone.utc) - ts
        secs = int(delta.total_seconds())
        if secs < 60:
            return "just now"
        if secs < 3600:
            return f"{secs // 60}m ago"
        if secs < 86400:
            return f"{secs // 3600}h ago"
        return f"{secs // 86400}d ago"
    except Exception:
        return "recently"


def _reload_process_scan_modules() -> None:
    """Reload the process-scan modules, dependency-first, so ``dashboard_procs`` binds against a
    fresh ``_subprocess_compat``: cleanup runs in the PRE-update process and a symbol the update
    added would otherwise ImportError after the code update succeeded. Called from the cleanup
    entry point so every caller (git path, ZIP fallback) is covered."""
    import importlib

    importlib.invalidate_caches()
    for mod_name in (
        "hermes_cli._subprocess_compat",
        "hermes_cli.dashboard_procs",
    ):
        mod = sys.modules.get(mod_name)
        if mod is not None:
            try:
                importlib.reload(mod)
            except Exception as exc:
                # warning, not debug: a failed reload surfaces as ImportError seconds later.
                logger.warning("Could not reload %s for post-update cleanup: %s", mod_name, exc)


def _finish_dashboard_update_cleanup(
    node_failures: list[str], already_restarted_units: "set[str] | None" = None
) -> None:
    """Refresh managed dashboards or stop stale manual ones after an update.

    *already_restarted_units*: systemd unit names (no ``.service``) the fleet-restart loop
    already restarted, so a Serve-only install isn't restarted a second time here.
    """
    from hermes_cli.update_cmd import _m, _reload_process_scan_modules
    if node_failures:
        print()
        print("  ℹ Leaving running dashboard process(es) untouched because the")
        print("    Node.js dependency refresh did not complete.")
        return

    _reload_process_scan_modules()

    stop_result = _m()._kill_stale_dashboard_processes(
        restart_managed=True, already_restarted_units=already_restarted_units
    )
    if not stop_result.get("unrecovered"):
        return

    print()
    print(
        "⚠ A web dashboard/serve process was stopped during update and could "
        "not be auto-restarted."
    )
    print("  Re-launch it when you want the web UI back:")
    print("    hermes dashboard --port <port>")


def _print_update_completion(message: str) -> None:
    """Print the outcome (with branch @ sha so drift is visible) plus, when launched by the
    dashboard with an action id, a receipt line the Desktop matches after restart."""
    from hermes_cli.update_cmd import _branch_head_suffix
    print(f"{message}{_branch_head_suffix()}")
    action_id = os.environ.get("HERMES_ACTION_ID", "")
    if len(action_id) == 32 and all(char in "0123456789abcdef" for char in action_id):
        print(f"=== hermes-update completed {action_id} ===")


def _read_project_version() -> str | None:
    """``version`` from the checkout's pyproject.toml (not importlib.metadata, which still
    describes the OLD version after a pull). None on any failure — cosmetic, never breaks."""
    from hermes_cli.update_cmd import _m
    try:
        import tomllib

        with open(_m().PROJECT_ROOT / "pyproject.toml", "rb") as fh:  # windows-footgun: ok — binary mode, tomllib requires bytes
            version = tomllib.load(fh).get("project", {}).get("version")
        return str(version) if version else None
    except Exception:
        return None


def _update_complete_message(pre_version: str | None) -> str:
    """Completion line with ``vA → vB`` when known; plain when either side is unknown or
    the version did not change."""
    post_version = _read_project_version()
    if pre_version and post_version and pre_version != post_version:
        return f"✓ Update complete! (v{pre_version} → v{post_version})"
    if post_version:
        return f"✓ Update complete! (v{post_version})"
    return "✓ Update complete!"


def _post_update_sqlite_runtime_status():
    """Return whether the interpreter used after update has safe SQLite."""
    from hermes_cli.update_cmd import _m
    from hermes_constants import project_venv_dir
    from hermes_cli.sqlite_runtime import probe_sqlite_runtime

    venv_dir = project_venv_dir(_m().PROJECT_ROOT)
    python = (
        venv_python_path(venv_dir, windows=_m()._is_windows())
        if venv_dir is not None
        else Path(sys.executable)
    )
    info = probe_sqlite_runtime(python)
    return info is not None and not info.wal_reset_vulnerable, info


def _print_verified_update_completion(message: str) -> bool:
    """Print a success completion only after probing the next Hermes runtime."""
    from hermes_cli.update_cmd import _post_update_sqlite_runtime_status
    if not message.startswith("✓"):
        _print_update_completion(message)
        return False
    sqlite_runtime_ok, sqlite_info = _post_update_sqlite_runtime_status()
    if sqlite_info is None:
        # Grace path: an unprobeable interpreter (dev checkout, no probe subprocess) must not
        # fail the update — only a POSITIVE vulnerable probe withholds success.
        logger.debug("Post-update SQLite runtime probe unavailable; not blocking")
        _print_update_completion(message)
        return True
    if sqlite_runtime_ok:
        _print_update_completion(message)
        return True
    print()
    detail = (
        f"SQLite {sqlite_info.sqlite_version_string} still has the "
        "WAL-reset corruption bug"
    )
    print(f"⚠ Update partially complete — {detail}.")
    print(
        "  Rebuild the Hermes venv with a uv-managed Python, restart Hermes, "
        "then verify with `hermes doctor`."
    )
    return False


def _clear_stale_sqlite_sidecars(db_path: Path) -> None:
    """Delete -wal/-shm/-journal next to *db_path*, immediately before overwriting it with a
    snapshot image.

    Snapshots are checkpointed ``sqlite3.backup()`` images with no WAL; copying replaces only
    the main file, so a leftover WAL from the OLD database would be replayed over the fresh
    image on next open (passes integrity_check while serving old contents). Safe because the
    caller has already declared that database corrupt.
    """
    for suffix in ("-wal", "-shm", "-journal"):
        db_path.with_name(db_path.name + suffix).unlink(missing_ok=True)


def _print_update_summary(
    *,
    node_failures: list,
    desktop_build_ok: bool,
    pre_update_version: str | None,
) -> bool:
    """Final banner. A failed Desktop rebuild is non-fatal but must not print ``✓ Update complete!``."""
    from hermes_cli.update_cmd import _post_update_sqlite_runtime_status, _update_complete_message
    sqlite_runtime_ok, sqlite_info = _post_update_sqlite_runtime_status()
    if sqlite_info is None:
        # Grace path: only a POSITIVE vulnerable probe demotes success to partial.
        sqlite_runtime_ok = True
    print()
    if node_failures or not desktop_build_ok or not sqlite_runtime_ok:
        parts = []
        if node_failures:
            parts.append(f"Node.js dependencies for {', '.join(node_failures)} did not refresh")
        if not desktop_build_ok:
            parts.append("the desktop app was not rebuilt and is still on the previous build")
        if not sqlite_runtime_ok and sqlite_info is not None:
            parts.append(
                f"SQLite {sqlite_info.sqlite_version_string} still has the "
                "WAL-reset corruption bug"
            )
        print("⚠ Update partially complete — " + "; ".join(parts) + ".")
        if node_failures:
            print("  Code and Python deps are updated, but the dashboard/TUI may")
            print("  be in a mixed state until the Node deps are rebuilt.")
        if not desktop_build_ok:
            print("  Run `hermes desktop` to retry the desktop rebuild.")
        if not sqlite_runtime_ok:
            print(
                "  The Python runtime remediation did not complete. Run `hermes "
                "update` again; if SQLite is unchanged, rebuild the Hermes venv "
                "with a uv-managed Python, restart Hermes, then verify with "
                "`hermes doctor`."
            )
    else:
        _print_update_completion(_update_complete_message(pre_update_version))
    return desktop_build_ok and sqlite_runtime_ok


def _restore_state_db_from_snapshot(state_path: Path, snap_state: Path) -> bool:
    """Replace *state_path* with the snapshot image; True when the result passes integrity.

    Stale sidecars are cleared first so the corrupt DB's WAL can't replay over the image.
    Refuses (False) while another process — or a live connection in THIS process — holds the
    DB: copying over a live writer's inode desyncs its page cache and its next checkpoint
    clobbers pages. Holder scan ``None`` proceeds (gateways drained; refusing on unknown would
    disable auto-restore on non-Linux). Raises OSError if the copy fails.
    """
    from hermes_cli.backup import _foreign_db_holder_pids, verify_sqlite_integrity
    from hermes_cli.sqlite_safe_read import LiveConnectionError, offline_file_access

    holders = _foreign_db_holder_pids(state_path)
    if holders:
        print(
            f"  ✗ Auto-restore refused: process(es) {holders} still hold "
            "state.db or its WAL open. Stop them (hermes gateway stop), "
            "then restore manually with /snapshot restore."
        )
        return False
    # The foreign-pid scan excludes THIS process; an in-process SessionDB handle is just as
    # live (it would checkpoint through deleted-inode sidecars). offline_file_access fails
    # CLOSED on any tracked connection and holds the lock across clear + copy.
    try:
        with offline_file_access(state_path, what="restore a snapshot over"):
            _clear_stale_sqlite_sidecars(state_path)
            shutil.copy2(snap_state, state_path)
    except LiveConnectionError as exc:
        print(
            f"  ✗ Auto-restore refused: {exc} Close the in-process database "
            "handles (or restart Hermes) and retry."
        )
        return False
    restored = verify_sqlite_integrity(state_path, check_header=True, run_pragma=True)
    return bool(restored.get("valid"))


def _verify_and_restore_one_state_db(home: Path, *, label: str) -> None:
    """Integrity check + auto-restore for ONE home's state.db from its newest valid snapshot.
    Never raises: a guard that crashes the update tail is worse than what it detects."""
    try:
        from hermes_cli.backup import _quick_snapshot_root, verify_sqlite_integrity

        state_path = home / "state.db"
        if not state_path.exists():
            return
        ok = verify_sqlite_integrity(state_path, check_header=True, run_pragma=True)
        if ok.get("valid"):
            logger.debug("Post-update state.db integrity OK (%s): %s", label, ok.get("message"))
            return
        print()
        print(
            f"⚠ state.db is corrupted after update ({label}): "
            + ok.get("message", "unknown error")
        )
        snap_root = _quick_snapshot_root(home)
        if not snap_root.exists():
            print("  ⚠ No pre-update snapshot for this home")
            return
        for snap_dir in sorted(
            (d for d in snap_root.iterdir() if d.is_dir()), reverse=True
        ):
            snap_state = snap_dir / "state.db"
            if not snap_state.exists():
                continue
            snap_ok = verify_sqlite_integrity(snap_state, check_header=True, run_pragma=True)
            if not snap_ok.get("valid"):
                continue
            try:
                if _restore_state_db_from_snapshot(state_path, snap_state):
                    print(f"  ✓ Auto-restored from snapshot {snap_dir.name} ({label})")
                else:
                    print("  ✗ Auto-restore FAILED — restored copy also failed integrity")
            except OSError as exc:
                print(f"  ✗ Auto-restore file copy failed: {exc}")
            return
        print("  ⚠ No valid pre-update snapshot found for this home")
    except Exception as exc:
        logger.debug("Post-update state.db guard (%s) failed: %s", label, exc)


def _verify_and_restore_state_dbs_post_update() -> None:
    """Integrity guard for the ROOT state.db AND every sibling profile's (the snapshot covers
    siblings, so the guard must too or a corrupt profile DB goes undetected)."""
    from hermes_cli.update_cmd import get_hermes_home
    home = get_hermes_home()
    _verify_and_restore_one_state_db(home, label="default home")
    with _best_effort('Sibling-profile state.db guard sweep failed: %s'):
        from hermes_cli.backup import _sibling_profile_homes

        for name, profile_home in _sibling_profile_homes(home):
            _verify_and_restore_one_state_db(profile_home, label=f"profile {name}")


def _print_bundled_skills_sync_report() -> None:
    """Run ``sync_skills`` (copies new, updates changed, respects user deletions) and print its summary."""
    from tools.skills_sync import sync_skills

    result = sync_skills(quiet=True)
    if result["copied"]:
        print(f"  + {len(result['copied'])} new: {', '.join(result['copied'])}")
    if result.get("updated"):
        print(f"  ↑ {len(result['updated'])} updated: {', '.join(result['updated'])}")
    if result.get("user_modified"):
        print(f"  ~ {len(result['user_modified'])} user-modified (kept)")
        print("    → see them: hermes skills list-modified  (diff/reset to resume updates)")
    if result.get("cleaned"):
        print(f"  − {len(result['cleaned'])} removed from manifest")
    if result.get("relocated"):
        print(
            f"  → {len(result['relocated'])} moved to new upstream paths: "
            f"{', '.join(result['relocated'])}"
        )
    if not result["copied"] and not result.get("updated"):
        print("  ✓ Skills are up to date")


def _ensure_fhs_path_guard() -> None:
    """Ensure /usr/local/bin is on PATH for RHEL-family root non-login shells (su, sudo -s,
    tmux), where neither /etc/bashrc nor .bash_profile adds it. Mirrors install.sh. Idempotent;
    no-op on non-Linux/non-root/non-FHS or when ``bash -i -c 'command -v hermes'`` resolves."""
    from hermes_cli.update_cmd import _m
    if _m().sys.platform != "linux":
        return
    try:
        if os.geteuid() != 0:  # windows-footgun: ok — Linux FHS helper, guarded by sys.platform == "linux" above + AttributeError catch
            return
    except AttributeError:
        return
    # Only for FHS-layout installs (link at /usr/local/bin/hermes).
    fhs_link = Path("/usr/local/bin/hermes")
    if not fhs_link.is_symlink() and not fhs_link.exists():
        return

    # ``bash -i -c`` sources ~/.bashrc but NOT ~/.bash_profile or /etc/profile — the exact
    # scenario where RHEL root loses /usr/local/bin.
    home = os.environ.get("HOME") or "/root"
    try:
        probe = subprocess.run(
            [
                "env",
                "-i",
                f"HOME={home}",
                f"TERM={os.environ.get('TERM', 'dumb')}",
                "bash",
                "-i",
                "-c",
                "command -v hermes",
            ],
            capture_output=True,
            text=True, encoding="utf-8", errors="replace",
            timeout=10,
        )
    except (FileNotFoundError, subprocess.TimeoutExpired):
        return  # no bash or probe hung — don't block update on this
    if probe.returncode == 0:
        return  # already on PATH, nothing to do

    path_line = 'export PATH="/usr/local/bin:$PATH"'
    path_comment = "# Hermes Agent — ensure /usr/local/bin is on PATH (RHEL non-login shells)"
    wrote_any = False
    for candidate in (".bashrc", ".bash_profile"):
        cfg = Path(home) / candidate
        if not cfg.is_file():
            continue
        try:
            existing = cfg.read_text(errors="replace", encoding="utf-8")
        except OSError:
            continue
        # Idempotency: any uncommented PATH line referencing /usr/local/bin (install.sh grep).
        already_guarded = any(
            "/usr/local/bin" in line
            and "PATH" in line
            and not line.lstrip().startswith("#")
            for line in existing.splitlines()
        )
        if already_guarded:
            continue
        try:
            with cfg.open("a", encoding="utf-8") as f:
                f.write("\n" + path_comment + "\n" + path_line + "\n")
        except OSError as e:
            print(f"  ⚠ Could not update {cfg}: {e}")
            continue
        print(f"  ✓ Added /usr/local/bin to PATH in {cfg}")
        wrote_any = True
    if wrote_any:
        print("    (reload your shell or run 'source ~/.bashrc' to pick it up)")


def _ensure_acp_launcher() -> None:
    r"""Self-heal a ``hermes-acp`` launcher next to ``hermes`` (mirrors install.sh): ACP hosts
    resolve it on the login-shell PATH but the console script lives in the venv. The shim
    delegates to the sibling ``hermes acp``, correct for every layout.

    No-op on Windows (install.ps1 stages launchers into ``$HermesHome\bin``, never
    ``venv\Scripts`` which would shadow the user's python) and where it already exists.
    Unwritable dirs are skipped. Idempotent.
    """
    from hermes_cli.update_cmd import _m
    if _m().sys.platform == "win32":
        # Windows launcher repair lives in _install_repair, not here.
        return
    for bin_dir in (Path.home() / ".local" / "bin", Path("/usr/local/bin")):
        hermes_cmd = bin_dir / "hermes"
        acp_cmd = bin_dir / "hermes-acp"
        try:
            if not (hermes_cmd.is_file() or hermes_cmd.is_symlink()):
                continue
            # is_symlink() catches broken symlinks exists() misses; never follow-and-overwrite.
            if acp_cmd.exists() or acp_cmd.is_symlink():
                continue
            shim = (
                "#!/usr/bin/env bash\n"
                "# Hermes Agent — ACP launcher (written by `hermes update`).\n"
                "# ACP hosts (Zed, JetBrains, Buzz) resolve the agent by this\n"
                "# command name on the login-shell PATH.\n"
                f'exec "{hermes_cmd}" acp "$@"\n'
            )
            acp_cmd.write_text(shim, encoding="utf-8")
            acp_cmd.chmod(acp_cmd.stat().st_mode | 0o755)
        except OSError:
            continue
        print(f"  ✓ Installed hermes-acp launcher → {acp_cmd}")


_PRE_UPDATE_SNAPSHOT_KEEP = 1


# Per-file cap for the quick snapshot (larger files skipped with a warning): it protects
# small hard-to-regenerate state, not a multi-GB state.db (24 GB cost ~60s + 24 GB/update).
_PRE_UPDATE_SNAPSHOT_MAX_FILE_SIZE = 1 << 30  # 1 GiB


def _resolve_pre_update_backup_mode(args) -> str:
    """Backup mode ``off``/``quick``/``full``. CLI flags win (``--no-backup`` beats ``--backup``);
    config accepts mode strings plus legacy booleans (true→full, false→off, which also disables
    the quick snapshot). Default ``quick``."""
    if getattr(args, "no_backup", False):
        return "off"
    if getattr(args, "backup", False):
        return "full"

    try:
        from hermes_cli.config import load_config

        cfg = load_config()
    except Exception as exc:
        logger.debug("Could not load config for pre-update backup: %s", exc)
        cfg = {}

    updates_cfg = cfg.get("updates", {}) if isinstance(cfg, dict) else {}
    raw = updates_cfg.get("pre_update_backup", "quick")

    if raw is True:
        return "full"
    if raw is False:
        return "off"
    mode = str(raw).strip().lower()
    if mode in ("off", "false", "none", "disabled"):
        return "off"
    if mode in ("full", "zip", "true"):
        return "full"
    if mode == "quick":
        return "quick"
    logger.warning("Unknown updates.pre_update_backup value %r — using 'quick'", raw)
    return "quick"


def _run_pre_update_backup(args) -> Optional[str]:
    """Run the pre-update backup; return the quick-snapshot id (None when off/failed). Never raises.

    ``off`` — nothing. ``quick`` (default) — snapshot of critical small files under
    ``state-snapshots/``, files over 1 GiB skipped so a bloated state.db can't stall the update.
    ``full`` — quick snapshot PLUS a zip of HERMES_HOME under ``backups/`` (``hermes import``).
    """
    from hermes_cli.update_cmd import _record_update_step
    mode = _resolve_pre_update_backup_mode(args)

    if mode == "off":
        if getattr(args, "no_backup", False):
            print("◆ Pre-update backup: skipped (--no-backup)")
            print()
        # Config-level off is silent: the user opted out.
        return None

    snapshot_id = None
    with _best_effort('Pre-update snapshot failed: %s'):
        from hermes_cli.backup import (
            _quick_snapshot_root,
            create_quick_snapshot,
            verify_sqlite_integrity,
        )

        # A later `from hermes_constants import get_hermes_home` in this function makes that
        # name function-local (unbound here), so alias explicitly.
        from hermes_cli.config import get_hermes_home as _get_home

        snapshot_id = create_quick_snapshot(
            label="pre-update",
            keep=_PRE_UPDATE_SNAPSHOT_KEEP,
            max_file_size=_PRE_UPDATE_SNAPSHOT_MAX_FILE_SIZE,
        )

        # Verify live state.db after the snapshot: a concurrent process (antivirus, killed
        # gateway, Windows filter driver) can corrupt it and we'd otherwise exit 0 silently.
        if snapshot_id:
            _src_path = _get_home() / "state.db"
            if _src_path.exists():
                _integrity = verify_sqlite_integrity(
                    _src_path,
                    check_header=True,
                    run_pragma=True,
                    max_bytes=_PRE_UPDATE_SNAPSHOT_MAX_FILE_SIZE,
                )
                if not _integrity.get("valid"):
                    _msg = _integrity.get("message", "unknown error")
                    print(f"  ⚠ state.db integrity check FAILED after snapshot: {_msg}")
                    _snap_root = _quick_snapshot_root(_get_home())
                    _snap_state = _snap_root / snapshot_id / "state.db"
                    if _snap_state.exists():
                        _snap_ok = verify_sqlite_integrity(
                            _snap_state, check_header=True, run_pragma=True
                        )
                        if _snap_ok.get("valid"):
                            print("  ✓ Snapshot copy is valid — continuing update.")
                            print("    If state.db is lost after update it will be auto-restored.")
                        else:
                            print(
                                "  ✗ Snapshot copy ALSO failed integrity — "
                                "the source was already corrupted before the backup."
                            )
                    else:
                        print("  ⚠ Snapshot does not contain state.db (was skipped or too large).")
                    print()
        if snapshot_id:
            print(f"◆ Pre-update snapshot: {snapshot_id}")

        # The code swap + fleet restart touch EVERY profile, so each gets the same snapshot
        # under its own state-snapshots/. Best-effort per profile.
        with _best_effort('Sibling profile snapshots failed: %s'):
            from hermes_cli.backup import create_pre_update_snapshots_all_profiles

            _sibling_snaps = create_pre_update_snapshots_all_profiles(
                keep=_PRE_UPDATE_SNAPSHOT_KEEP,
                max_file_size=_PRE_UPDATE_SNAPSHOT_MAX_FILE_SIZE,
            )
            if _sibling_snaps:
                print(f"◆ Sibling profile snapshot(s): " + ", ".join(sorted(_sibling_snaps)))
                _record_update_step(
                    "sibling_profile_snapshots",
                    True,
                    ", ".join(
                        f"{k}={v}" for k, v in sorted(_sibling_snaps.items())
                    ),
                )
                import hermes_cli.update_cmd_config as _cfg

                # The reader lives in update_cmd_config; write ITS module global, not ours.
                _cfg._LAST_SIBLING_SNAPSHOTS = _sibling_snaps

    if mode != "full":
        if snapshot_id:
            print()
        return snapshot_id

    try:
        from hermes_cli.backup import create_pre_update_backup
    except Exception as exc:
        print(f"⚠ Pre-update backup: could not load backup module ({exc}); continuing update.")
        print()
        return snapshot_id

    try:
        from hermes_cli.config import load_config

        _keep = (load_config() or {}).get("updates", {}).get("backup_keep", 5)
    except Exception:
        _keep = 5

    print("◆ Creating pre-update backup...")
    t0 = _time.monotonic()
    try:
        out_path = create_pre_update_backup(keep=int(_keep))
    except Exception as exc:  # defensive — helper already swallows, but just in case
        print(f"  ⚠ Backup failed: {exc}")
        print("  Continuing with update.")
        print()
        return snapshot_id

    elapsed = _time.monotonic() - t0

    if out_path is None:
        print("  ⚠ Backup skipped (no files found or write failed); continuing update.")
        print()
        return snapshot_id

    try:
        size_bytes = out_path.stat().st_size
    except OSError:
        size_bytes = 0

    from hermes_cli.sizefmt import format_bytes

    size_str = format_bytes(size_bytes)

    # display_hermes_home so the user sees ~/.hermes/...
    try:
        from hermes_constants import get_hermes_home, display_hermes_home

        home = get_hermes_home()
        try:
            display_path = f"{display_hermes_home()}/{out_path.relative_to(home)}"
        except ValueError:
            display_path = str(out_path)
    except Exception:
        display_path = str(out_path)

    print(f"  Saved:    {display_path} ({size_str}, {elapsed:.1f}s)")
    print(f"  Restore:  hermes import {out_path}")
    print("  Disable:  set updates.pre_update_backup: quick (or off) in config.yaml")
    print()
    return snapshot_id


def _sweep_bytecode_after_update(branch: str) -> None:
    """Clear stale ``__pycache__`` (else gateway restart ImportErrors on names absent from old
    bytecode), re-stamp the fingerprint, refresh the bootstrap cache scripts."""
    from hermes_cli.update_cmd import _m
    removed = _m()._clear_bytecode_cache(_m().PROJECT_ROOT)
    if removed:
        print(f"  ✓ Cleared {removed} stale __pycache__ director{'y' if removed == 1 else 'ies'}")
    _m()._record_bytecode_fingerprint()
    _m()._refresh_bootstrap_cache_scripts(branch)


def _sync_profiles_after_update() -> None:
    """Best-effort per-profile syncs: bundled skills, ``.env`` backfill, Honcho profiles."""
    # All profiles incl. the active one: seed_profile_skills() subprocesses with an explicit
    # HERMES_HOME, so sync_skills()'s module-level HERMES_HOME cache can't skew it.
    with suppress(Exception):
        from hermes_cli.profiles import (
            list_profiles,
            seed_profile_skills,
        )

        all_profiles = list_profiles()
        if all_profiles:
            print()
            print("→ Syncing bundled skills to all profiles...")
            for p in all_profiles:
                try:
                    r = seed_profile_skills(p.path, quiet=True)
                    if r and r.get("skipped_opt_out"):
                        status = "opted out (--no-skills)"
                    elif r:
                        copied = len(r.get("copied", []))
                        updated = len(r.get("updated", []))
                        modified = len(r.get("user_modified", []))
                        parts = []
                        if copied:
                            parts.append(f"+{copied} new")
                        if updated:
                            parts.append(f"↑{updated} updated")
                        if modified:
                            parts.append(f"~{modified} user-modified")
                        status = ", ".join(parts) if parts else "up to date"
                    else:
                        status = "sync failed"
                    print(f"  {p.name}: {status}")
                except Exception as pe:
                    print(f"  {p.name}: error ({pe})")

    # Backfill .env for profiles created before .env seeding (copy the default's) so they
    # keep the credentials they were effectively using.
    with suppress(Exception):
        from hermes_cli.profiles import backfill_profile_envs

        backfilled = backfill_profile_envs(quiet=True)
        if backfilled:
            print()
            print(
                f"→ Seeded .env for {len(backfilled)} profile(s) "
                f"(copied from default): {', '.join(backfilled)}"
            )

    with suppress(Exception):
        from plugins.memory.honcho.cli import sync_honcho_profiles_quiet

        synced = sync_honcho_profiles_quiet()
        if synced:
            print(f"\n-> Honcho: synced {synced} profile(s)")


def _print_post_update_notices_and_self_heals() -> None:
    """Best-effort notices (FTS optimize, curator) and self-heals (FHS PATH, ACP launcher,
    Windows bin launchers, cua-driver refresh) that run after the summary."""
    from hermes_cli.update_cmd import _m, _print_curator_first_run_notice, _print_curator_recent_run_notice

    # v23 FTS layout is opt-in (existing indexes untouched); surface the command here.
    with _best_effort('FTS optimize notice failed: %s'):
        _print_fts_optimize_available_notice()

    with _best_effort('Curator first-run notice failed: %s'):
        _print_curator_first_run_notice()

    with _best_effort('Curator recent-run notice failed: %s'):
        _print_curator_recent_run_notice()

    with _best_effort('FHS PATH guard check failed: %s'):
        _ensure_fhs_path_guard()

    with _best_effort('hermes-acp launcher self-heal failed: %s'):
        _ensure_acp_launcher()

    # Windows launchers into the managed bin dir: in-checkout launchers were swept by the
    # autostash (--include-untracked) and updates never run install.ps1. No-op on POSIX.
    with _best_effort('Windows bin launcher migration failed: %s'):
        from hermes_cli._install_repair import migrate_windows_bin_path

        migrate_windows_bin_path(_m().PROJECT_ROOT)

    # cua-driver refresh, no-op unless on PATH; tied to update for a predictable cadence
    # without a per-launch GitHub API call.
    with _best_effort('cua-driver refresh failed: %s'):
        refresh_cua_driver = True
        with _best_effort('Could not read updates.refresh_cua_driver: %s'):
            from hermes_cli.config import load_config

            _update_cfg = (load_config() or {}).get("updates", {})
            if isinstance(_update_cfg, dict):
                refresh_cua_driver = bool(_update_cfg.get("refresh_cua_driver", True))

        if (
            refresh_cua_driver
            and sys.platform in ("darwin", "win32", "linux")
            and shutil.which("cua-driver")
        ):
            from hermes_cli.tools_config import install_cua_driver

            print()
            print("→ Refreshing cua-driver (Computer Use)...")
            # require_confirmed_update: install only when check-update positively reports a
            # newer release (update must stay fast; `computer-use install --upgrade` forces).
            # Windows defers even confirmed updates (installer may need console/UAC consent).
            install_cua_driver(
                upgrade=True,
                require_confirmed_update=True,
                show_installer_progress=False,
            )


def _run_post_update_maintenance(
    *,
    assume_yes,
    gateway_mode,
    pre_update_snapshot_id,
    had_desktop_app_before_update,
    node_failures,
    desktop_build_ok,
    pre_update_version,
) -> bool:
    """Post-pull housekeeping: state.db restore, catalog/skills/profile syncs, config migration,
    the update summary (verdict returned), and best-effort notices/self-heals. Every step is
    isolated so none can fail the update."""
    from hermes_cli.update_cmd import _check_and_apply_config_migration, _m

    # macOS TCC: Desktop bundles are re-signed each update, so old grants can go stale
    # (toggle ON, yet macOS re-prompts with no Allow button). Tell users how to re-grant.
    if sys.platform == "darwin" and had_desktop_app_before_update:
        print()
        print(
            "  ℹ macOS: if Hermes re-prompts for permissions you already "
            "granted (toggle shows ON), the stored grant is stale — run "
            "`tccutil reset ScreenCapture com.nousresearch.hermes` (repeat "
            "per affected service), toggle it ON in System Settings, then "
            "fully quit & relaunch once."
        )

    # macOS TCC interpreter anchor; boot-gated — a failed probe leaves the venv untouched.
    try:
        from hermes_cli.macos_tcc_anchor import ensure_tcc_anchor

        ensure_tcc_anchor()
    except Exception:
        logger.debug("macOS TCC anchor refresh skipped", exc_info=True)

    # state.db integrity guard for root home AND every profile; restore from own snapshot.
    with _best_effort('Post-update state.db integrity check failed: %s'):
        _verify_and_restore_state_dbs_post_update()

    # Seed the model-catalog cache from the checkout instead of a bot-gated, flaky fetch.
    with _best_effort('Model catalog seed during update failed: %s'):
        from hermes_cli.model_catalog import seed_cache_from_checkout

        if seed_cache_from_checkout(_m().PROJECT_ROOT):
            print("  ✓ Model catalog cache refreshed from checkout")

    with _best_effort('Skills sync during update failed: %s'):
        print()
        print("→ Syncing bundled skills...")
        _print_bundled_skills_sync_report()

    _sync_profiles_after_update()

    _check_and_apply_config_migration(
        assume_yes=assume_yes,
        gateway_mode=gateway_mode,
        pre_update_snapshot_id=pre_update_snapshot_id,
    )

    update_complete = _print_update_summary(
        node_failures=node_failures,
        desktop_build_ok=desktop_build_ok,
        pre_update_version=pre_update_version,
    )

    _print_post_update_notices_and_self_heals()
    return update_complete