#!/usr/bin/env python3
"""``run-team.py`` — R720 agent-team operator entry CLI (design §3.3.1, §7.1 P1).

This is the **entry CLI** named in the design (§2 "entry CLI ``run-team.py``";
§9 "operator CLI"). It is the small manual path over the durable
``pending_questions`` ledger that §3.3.1 ("Manual path") requires::

    A small CLI over the ledger lets an operator list ``open``/``parked``
    questions, re-deliver, force-expire, or answer on a task's behalf; a stuck
    task parks rather than spins. Destructive CLI actions (force-expire,
    answer-on-behalf, force-resume) are audit-logged and require an explicit
    confirmation flag.

It imports the committed FOUNDATION contracts verbatim — it does not redefine
them:

* :mod:`agent_team.db.schema` — :func:`connect`, :func:`init_db`,
  :func:`answer_question`, :func:`expire_question`, :func:`supersede_question`,
  :data:`QUESTION_STATES`.
* :mod:`agent_team.state_store` — :func:`atomic_write` for the append-only,
  crash-safe audit log of destructive actions (§6.7 discipline).

Per the build constraints this is **pre-deployment scaffolding**: it provisions
nothing, enables no live CI, and performs no network or rsync. It only reads and
mutates the local SQLite ledger and writes a local audit log.

Subcommands (P1 surface):

* ``init-db`` — create/upgrade the agent-team tables in the ledger DB
  (idempotent; wraps :func:`init_db`).
* ``list`` — list ``open`` (default) or any-status pending questions; with
  ``--parked`` it lists questions whose status is read as parked context. Pure
  read; no confirmation needed.
* ``show`` — print one question row by ``question_id``. Pure read.
* ``expire`` — force-expire an ``open`` question (DESTRUCTIVE: requires
  ``--confirm``; audit-logged). Maps to :func:`expire_question`.
* ``answer`` — answer a question on a task's behalf (DESTRUCTIVE: requires
  ``--confirm``; audit-logged). Maps to :func:`answer_question`.
* ``supersede`` — mark a stale question ``superseded`` (DESTRUCTIVE: requires
  ``--confirm``; audit-logged). Maps to :func:`supersede_question`.

Exit codes: ``0`` success, ``1`` operational failure (e.g. row not found, the
compare-and-set lost the race), ``2`` usage error (argparse).
"""

from __future__ import annotations

import argparse
import getpass
import json
import os
import sqlite3
import sys
from datetime import datetime, timezone
from pathlib import Path
from typing import Any, Sequence

# ``run-team.py`` lives in ``agent-team/`` next to the importable ``agent_team``
# package. The hyphenated filename cannot itself be imported, so when run as a
# script we make the sibling package importable without an editable install
# (mirrors tests/conftest.py).
_CLI_DIR = Path(__file__).resolve().parent
if str(_CLI_DIR) not in sys.path:
    sys.path.insert(0, str(_CLI_DIR))

from agent_team.db.schema import (  # noqa: E402  (path bootstrap must precede)
    QUESTION_STATES,
    answer_question,
    connect,
    expire_question,
    init_db,
    reopen_question,
    supersede_question,
)

__all__ = [
    "build_parser",
    "main",
]

# Default ledger DB location. Kept out of the repo (the package .gitignore
# excludes ``state/`` and ``*.sqlite``) so durable state is never committed.
_DEFAULT_DB = _CLI_DIR / "state" / "agent_team.sqlite"

# Default audit log for destructive actions, alongside the ledger DB.
_DEFAULT_AUDIT_LOG = _CLI_DIR / "state" / "audit.log.jsonl"

# Columns selected for list/show rendering, in display order.
_QUESTION_COLUMNS: tuple[str, ...] = (
    "question_id",
    "thread_id",
    "turn",
    "status",
    "transport",
    "channel_ref",
    "posted_at",
    "deadline_at",
    "answered_at",
    "answered_via",
)

# Destructive subcommands that require ``--confirm`` and are audit-logged.
# ``force-resume`` is the design-named operator verb (§3.3.1/§6.6); ``supersede``
# is kept as its lower-level alias. ``redeliver`` is NOT here — it is idempotent
# and non-destructive (it only clears a delivery ref), though it is still
# audit-logged for provenance.
_DESTRUCTIVE_ACTIONS: frozenset[str] = frozenset(
    {"expire", "answer", "supersede", "force-resume"}
)


def _utc_now_iso() -> str:
    """Return the current UTC time as an ISO-8601 string (audit timestamps)."""
    return datetime.now(timezone.utc).isoformat()


def _default_operator() -> str:
    """Best-effort OS login for audit attribution (never an empty string).

    A previous empty default left destructive actions non-attributable (the
    audit record named no one). Defaulting to the OS login keeps the §3.3.1
    "audit-logged AND attributable" guarantee even when --operator is omitted;
    falls back to "unknown" only if the login cannot be resolved.
    """
    try:
        user = getpass.getuser()
    except Exception:  # noqa: BLE001 - getuser can raise on odd environments
        return "unknown"
    return user or "unknown"


def _row_to_dict(row: sqlite3.Row) -> dict[str, Any]:
    """Project a ``pending_questions`` row to a plain dict for display."""
    return {col: row[col] for col in _QUESTION_COLUMNS if col in row.keys()}


def _append_audit(audit_log: Path, entry: dict[str, Any]) -> None:
    """Append one JSON audit record with an atomic ``O_APPEND`` single write.

    Destructive actions (§3.3.1) must leave an attributable trail. A previous
    read-modify-rewrite design lost records under concurrent operators (two
    processes each read the same bytes and the last rewrite wins). Instead each
    record is one line written with ``O_APPEND``: the kernel serializes the
    append and a write below ``PIPE_BUF`` is atomic on POSIX, so concurrent
    appends never clobber each other. The file is created mode ``0600``
    (operator identity / action content is sensitive) and re-chmod'd in case it
    pre-existed wider. A failure here raises ``OSError`` BEFORE any ledger
    mutation, preserving the audit-before-mutate guarantee.
    """
    audit_log = Path(audit_log)
    audit_log.parent.mkdir(parents=True, exist_ok=True)
    line = (json.dumps(entry, sort_keys=True) + "\n").encode("utf-8")
    fd = os.open(str(audit_log), os.O_WRONLY | os.O_CREAT | os.O_APPEND, 0o600)
    try:
        os.write(fd, line)
    finally:
        os.close(fd)
    os.chmod(audit_log, 0o600)


def _audit_attempt(
    audit_log: Path,
    action: str,
    *,
    question_id: str,
    operator: str,
    detail: dict[str, Any] | None = None,
) -> None:
    """Record the *intent* to perform a destructive action BEFORE it mutates.

    §3.3.1 requires every destructive action to be audit-logged. Writing the
    attempt before the ledger mutation closes the "mutation applied with no
    audit record" gap: if this append fails (e.g. an unwritable audit path) it
    raises before any ledger row is touched, so the action aborts cleanly with
    nothing changed. The matching :func:`_audit_outcome` records what happened.
    """
    _append_audit(
        audit_log,
        {
            "ts": _utc_now_iso(),
            "action": action,
            "phase": "attempt",
            "question_id": question_id,
            "operator": operator,
            **(detail or {}),
        },
    )


def _audit_outcome(
    audit_log: Path,
    action: str,
    *,
    question_id: str,
    operator: str,
    applied: bool,
    detail: dict[str, Any] | None = None,
) -> None:
    """Record the *result* of a destructive action AFTER it ran.

    Carries ``applied`` (did the compare-and-set change a row). Pairs with the
    :func:`_audit_attempt` record written before the mutation, so even if this
    outcome append fails the attempt already proves the action was made.
    """
    _append_audit(
        audit_log,
        {
            "ts": _utc_now_iso(),
            "action": action,
            "phase": "outcome",
            "question_id": question_id,
            "operator": operator,
            "applied": applied,
            **(detail or {}),
        },
    )


def _require_confirm(action: str, *, confirm: bool) -> None:
    """Raise unless a destructive ``action`` was explicitly confirmed.

    Mirrors the §3.3.1 rule: force-expire, answer-on-behalf, and force-resume
    are audit-logged AND require an explicit confirmation flag. Failing closed
    here means a typo can never silently mutate a live task's ledger row.
    """
    if action in _DESTRUCTIVE_ACTIONS and not confirm:
        raise PermissionError(
            f"refusing destructive action '{action}' without --confirm "
            f"(force-expire / answer-on-behalf / supersede are gated, §3.3.1)"
        )


def _fetch_question(conn: sqlite3.Connection, question_id: str) -> sqlite3.Row | None:
    """Return the ledger row for ``question_id`` or ``None`` if absent."""
    return conn.execute(
        "SELECT * FROM pending_questions WHERE question_id = ?",
        (question_id,),
    ).fetchone()


# --------------------------------------------------------------------------- #
# Subcommand handlers. Each returns a process exit code (0 ok, 1 op failure).
# --------------------------------------------------------------------------- #


def _cmd_init_db(args: argparse.Namespace, *, out: Any) -> int:
    """Create/upgrade the agent-team tables (idempotent)."""
    init_db(args.db)
    print(f"initialized ledger DB at {args.db}", file=out)
    return 0


def _cmd_list(args: argparse.Namespace, *, out: Any) -> int:
    """List pending questions, optionally filtered by status.

    Default lists ``open`` questions (the operator's "what is waiting" view).
    ``--status STATE`` narrows to one lifecycle state; ``--all`` lists every
    state. ``--parked`` is a convenience alias that surfaces the parked-task
    context an operator chases: questions that are no longer ``open`` (answered
    but never resumed, expired, or superseded) and so may back a parked task.
    """
    conn = connect(args.db)
    try:
        if args.all:
            rows = conn.execute(
                "SELECT * FROM pending_questions ORDER BY thread_id, turn"
            ).fetchall()
        elif args.parked:
            placeholders = ",".join("?" for _ in _PARKED_STATES)
            rows = conn.execute(
                f"SELECT * FROM pending_questions WHERE status IN ({placeholders}) "
                "ORDER BY thread_id, turn",
                tuple(_PARKED_STATES),
            ).fetchall()
        else:
            rows = conn.execute(
                "SELECT * FROM pending_questions WHERE status = ? "
                "ORDER BY thread_id, turn",
                (args.status,),
            ).fetchall()
    finally:
        conn.close()

    payload = [_row_to_dict(row) for row in rows]
    print(json.dumps(payload, indent=2, sort_keys=True), file=out)
    return 0


def _cmd_show(args: argparse.Namespace, *, out: Any) -> int:
    """Print one question row by ``question_id`` (pure read)."""
    conn = connect(args.db)
    try:
        row = _fetch_question(conn, args.question_id)
    finally:
        conn.close()
    if row is None:
        print(f"no such question: {args.question_id}", file=sys.stderr)
        return 1
    print(json.dumps(_row_to_dict(row), indent=2, sort_keys=True), file=out)
    return 0


def _cmd_expire(args: argparse.Namespace, *, out: Any) -> int:
    """Force-expire an ``open`` question (destructive; audit-logged).

    Audits the attempt BEFORE mutating so a mutation can never land without a
    trail (§3.3.1); records the outcome after.
    """
    _require_confirm("expire", confirm=args.confirm)
    _audit_attempt(
        args.audit_log, "expire", question_id=args.question_id, operator=args.operator
    )
    conn = connect(args.db)
    try:
        changed = expire_question(conn, question_id=args.question_id)
    finally:
        conn.close()
    _audit_outcome(
        args.audit_log,
        "expire",
        question_id=args.question_id,
        operator=args.operator,
        applied=changed,
    )
    if not changed:
        print(
            f"expire no-op: question {args.question_id} was not 'open' "
            "(already answered/expired/superseded or absent)",
            file=sys.stderr,
        )
        return 1
    print(f"expired question {args.question_id}", file=out)
    return 0


def _cmd_redeliver(args: argparse.Namespace, *, out: Any) -> int:
    """Clear an ``open`` question's ``channel_ref`` so it is re-posted (§3.3.1).

    The design's "re-deliver" operator action. Re-delivery itself is performed
    by the transport reconcile loop; clearing ``channel_ref`` makes that loop
    re-post and record a fresh ref. Idempotent and non-destructive (the question
    stays ``open``), so it needs no ``--confirm`` — but it is audit-logged for
    provenance. Returns ``1`` if the question is absent or not ``open``.
    """
    _audit_attempt(
        args.audit_log,
        "redeliver",
        question_id=args.question_id,
        operator=args.operator,
    )
    conn = connect(args.db)
    try:
        row = _fetch_question(conn, args.question_id)
        if row is None:
            applied = False
            prior_ref = None
            status = None
        elif row["status"] != "open":
            applied = False
            prior_ref = row["channel_ref"]
            status = row["status"]
        else:
            prior_ref = row["channel_ref"]
            status = "open"
            conn.execute(
                "UPDATE pending_questions SET channel_ref=NULL WHERE question_id=?",
                (args.question_id,),
            )
            applied = True
    finally:
        conn.close()
    _audit_outcome(
        args.audit_log,
        "redeliver",
        question_id=args.question_id,
        operator=args.operator,
        applied=applied,
        detail={"prior_channel_ref": prior_ref},
    )
    if not applied:
        reason = "absent" if status is None else f"status={status}, not open"
        print(
            f"redeliver no-op: question {args.question_id} ({reason}); "
            "nothing to re-post",
            file=sys.stderr,
        )
        return 1
    print(
        f"cleared channel_ref for {args.question_id}; reconcile loop will re-post",
        file=out,
    )
    return 0


def _cmd_answer(args: argparse.Namespace, *, out: Any) -> int:
    """Answer a question on a task's behalf (destructive; audit-logged).

    Uses the foundation first-answer-wins compare-and-set: succeeds only if the
    question is still ``open``. ``--answer`` is stored verbatim as the answer
    payload string; ``--via`` records the answering identity for the audit
    trail. The audit log records the operator regardless of outcome.
    """
    _require_confirm("answer", confirm=args.confirm)
    via = args.via or f"cli:{args.operator}"
    _audit_attempt(
        args.audit_log,
        "answer",
        question_id=args.question_id,
        operator=args.operator,
        detail={"answered_via": via},
    )
    conn = connect(args.db)
    try:
        changed = answer_question(
            conn,
            question_id=args.question_id,
            answer_json=args.answer,
            answered_via=via,
        )
    finally:
        conn.close()
    _audit_outcome(
        args.audit_log,
        "answer",
        question_id=args.question_id,
        operator=args.operator,
        applied=changed,
        detail={"answered_via": via},
    )
    if not changed:
        print(
            f"answer no-op: question {args.question_id} was not 'open' "
            "(already answered/expired/superseded or absent)",
            file=sys.stderr,
        )
        return 1
    print(f"answered question {args.question_id} (via {via})", file=out)
    return 0


def _cmd_supersede(args: argparse.Namespace, *, out: Any) -> int:
    """Mark a stale ``open``/``answered`` question ``superseded`` (destructive)."""
    _require_confirm("supersede", confirm=args.confirm)
    _audit_attempt(
        args.audit_log,
        "supersede",
        question_id=args.question_id,
        operator=args.operator,
    )
    conn = connect(args.db)
    try:
        changed = supersede_question(conn, question_id=args.question_id)
    finally:
        conn.close()
    _audit_outcome(
        args.audit_log,
        "supersede",
        question_id=args.question_id,
        operator=args.operator,
        applied=changed,
    )
    if not changed:
        print(
            f"supersede no-op: question {args.question_id} was not "
            "'open'/'answered' (already expired/superseded or absent)",
            file=sys.stderr,
        )
        return 1
    print(f"superseded question {args.question_id}", file=out)
    return 0


def _cmd_force_resume(args: argparse.Namespace, *, out: Any) -> int:
    """Force-resume a parked task's question (destructive; audit-logged).

    The design-named operator verb (§3.3.1 / §6.6 "an operator can force-resume
    ... a parked task via the CLI"). A task parks when its clarifier question
    EXPIRES with no answer, so the un-park action is to RE-OPEN that expired
    question (:func:`agent_team.db.schema.reopen_question`) so the normal
    delivery → answer → resume flow can proceed.

    Crucially this does NOT ``supersede`` the row: superseding an ``answered``
    row would flip it out of the state the recovery sweep resumes from, making a
    stuck-but-answered task permanently un-resumable — the opposite of
    force-resume. So:

    * ``expired`` (the parked case) → reopened; returns 0.
    * ``answered`` (answered but not yet resumed) → already eligible for the
      recovery resume sweep; intent is recorded and we report that, no mutation.
    * ``open`` / ``superseded`` / absent → nothing to force; reported as a no-op.
    """
    _require_confirm("force-resume", confirm=args.confirm)
    _audit_attempt(
        args.audit_log,
        "force-resume",
        question_id=args.question_id,
        operator=args.operator,
        detail={"resume_requested": True},
    )
    conn = connect(args.db)
    try:
        row = _fetch_question(conn, args.question_id)
        status = None if row is None else row["status"]
        reopened = False
        if status == "expired":
            reopened = reopen_question(conn, question_id=args.question_id)
    finally:
        conn.close()
    _audit_outcome(
        args.audit_log,
        "force-resume",
        question_id=args.question_id,
        operator=args.operator,
        applied=reopened,
        detail={"resume_requested": True, "prior_status": status},
    )
    if reopened:
        print(
            f"force-resume: reopened expired question {args.question_id}; "
            "it will be re-delivered for an answer",
            file=out,
        )
        return 0
    if status == "answered":
        print(
            f"force-resume: question {args.question_id} is answered and pending "
            "resume; the recovery sweep will resume it (intent recorded)",
            file=out,
        )
        return 0
    print(
        f"force-resume no-op: question {args.question_id} "
        f"({'absent' if status is None else f'status={status}'}) is not parked",
        file=sys.stderr,
    )
    return 1


# Statuses an operator treats as "parked context": a task whose only pending
# question is no longer open may be parked (answered-but-unresumed, expired, or
# superseded). ``open`` is excluded — that is the live-waiting view (default
# ``list``). Derived from the foundation QUESTION_STATES so it stays in sync.
_PARKED_STATES: tuple[str, ...] = tuple(s for s in QUESTION_STATES if s != "open")


def build_parser() -> argparse.ArgumentParser:
    """Construct the argparse parser for ``run-team.py`` (no side effects)."""
    parser = argparse.ArgumentParser(
        prog="run-team.py",
        description=(
            "R720 agent-team operator CLI — manual path over the durable "
            "pending_questions ledger (design §3.3.1)."
        ),
    )
    parser.add_argument(
        "--db",
        type=Path,
        default=_DEFAULT_DB,
        help=f"path to the agent-team SQLite ledger (default: {_DEFAULT_DB})",
    )
    parser.add_argument(
        "--audit-log",
        type=Path,
        default=_DEFAULT_AUDIT_LOG,
        dest="audit_log",
        help=(
            "append-only JSONL audit log for destructive actions "
            f"(default: {_DEFAULT_AUDIT_LOG})"
        ),
    )
    parser.add_argument(
        "--operator",
        default=_default_operator(),
        help="operator identity recorded in the audit log for destructive actions "
        "(defaults to the OS login so the trail is always attributable)",
    )

    sub = parser.add_subparsers(dest="command", required=True)

    p_init = sub.add_parser("init-db", help="create/upgrade the ledger tables")
    p_init.set_defaults(func=_cmd_init_db)

    p_list = sub.add_parser("list", help="list pending questions (read-only)")
    list_filter = p_list.add_mutually_exclusive_group()
    list_filter.add_argument(
        "--status",
        choices=QUESTION_STATES,
        default="open",
        help="lifecycle status to list (default: open)",
    )
    list_filter.add_argument(
        "--all",
        action="store_true",
        help="list questions in every lifecycle status",
    )
    list_filter.add_argument(
        "--parked",
        action="store_true",
        help="list non-open questions (parked-task context)",
    )
    p_list.set_defaults(func=_cmd_list)

    p_show = sub.add_parser("show", help="print one question row (read-only)")
    p_show.add_argument("question_id", help="the question_id to show")
    p_show.set_defaults(func=_cmd_show)

    p_redeliver = sub.add_parser(
        "redeliver",
        help="clear an open question's channel_ref so it is re-posted",
    )
    p_redeliver.add_argument("question_id", help="the question_id to re-deliver")
    p_redeliver.set_defaults(func=_cmd_redeliver)

    p_expire = sub.add_parser(
        "expire", help="force-expire an open question (destructive)"
    )
    p_expire.add_argument("question_id", help="the question_id to expire")
    p_expire.add_argument(
        "--confirm",
        action="store_true",
        help="required: confirm this destructive, audit-logged action",
    )
    p_expire.set_defaults(func=_cmd_expire)

    p_answer = sub.add_parser(
        "answer", help="answer a question on a task's behalf (destructive)"
    )
    p_answer.add_argument("question_id", help="the question_id to answer")
    p_answer.add_argument(
        "--answer",
        required=True,
        help="the answer payload (stored verbatim as answer_json)",
    )
    p_answer.add_argument(
        "--via",
        default="",
        help="answering identity for answered_via (default: cli:<operator>)",
    )
    p_answer.add_argument(
        "--confirm",
        action="store_true",
        help="required: confirm this destructive, audit-logged action",
    )
    p_answer.set_defaults(func=_cmd_answer)

    p_supersede = sub.add_parser(
        "supersede", help="mark a stale question superseded (destructive)"
    )
    p_supersede.add_argument("question_id", help="the question_id to supersede")
    p_supersede.add_argument(
        "--confirm",
        action="store_true",
        help="required: confirm this destructive, audit-logged action",
    )
    p_supersede.set_defaults(func=_cmd_supersede)

    p_resume = sub.add_parser(
        "force-resume",
        help="force-resume a parked task's question (destructive)",
    )
    p_resume.add_argument("question_id", help="the question_id to force-resume")
    p_resume.add_argument(
        "--confirm",
        action="store_true",
        help="required: confirm this destructive, audit-logged action",
    )
    p_resume.set_defaults(func=_cmd_force_resume)

    return parser


def main(argv: Sequence[str] | None = None, *, out: Any = None) -> int:
    """CLI entry point. Returns a process exit code.

    ``argv`` defaults to ``sys.argv[1:]``; ``out`` defaults to ``sys.stdout``
    (injectable for tests). Operational failures return ``1``; a missing
    ``--confirm`` on a destructive action raises :class:`PermissionError`,
    surfaced as exit code ``1`` with a stderr message.
    """
    out = out if out is not None else sys.stdout
    parser = build_parser()
    args = parser.parse_args(argv)
    try:
        return int(args.func(args, out=out))
    except PermissionError as exc:
        # A refused destructive action (no --confirm) or an unwritable audit
        # path. The attempt-before-mutate ordering means nothing was mutated.
        print(f"error: {exc}", file=sys.stderr)
        return 1
    except OSError as exc:
        # Any other audit-log / filesystem failure (e.g. the audit append could
        # not be written). Surfaced cleanly instead of as an uncaught traceback;
        # if the attempt record was written, the action is on the trail.
        print(f"error: audit/IO failure: {exc}", file=sys.stderr)
        return 1


if __name__ == "__main__":  # pragma: no cover
    raise SystemExit(main())