#!/usr/bin/env python3
"""task-worktree — 多任务并行开发的空间管理（git worktree 生命周期）

执行体 = 本脚本（纯标准库）。规格见 docs/环境与部署/并行任务工作树方案.md，
用法与铁律见同目录 SKILL.md。

退出码：0=成功 / 1=操作失败 / 2=前置或环境错误 / 3=用法错误
"""

import argparse
import json
import os
import re
import subprocess
import sys
import tempfile
import time
from pathlib import Path

# 输出统一 UTF-8，避免被控制台代码页（cp936）转码破坏
for _stream in (sys.stdout, sys.stderr):
    try:
        _stream.reconfigure(encoding="utf-8")
    except Exception:
        pass

EXIT_OK, EXIT_FAIL, EXIT_ENV, EXIT_USAGE = 0, 1, 2, 3

BRANCH_PREFIX = "task/"
MAX_CONCURRENT = 3
LOCK_NAMES = ("build", "bench")
LOCK_TTL_HOURS = 6.0  # 超过此持有时间即视为陈旧锁，下次 acquire 自动接管
JUNCTION_SPECS = (
    (".venv", "Python 环境"),
    ("simulator/SDL2", "模拟器 SDL2 SDK"),
)
FILE_ATTRIBUTE_REPARSE_POINT = 0x400

ID_RE = re.compile(r"^[A-Za-z0-9][A-Za-z0-9_.-]*$")
SLUG_RE = re.compile(r"^[a-z0-9][a-z0-9-]*$")


class Fail(Exception):
    """操作失败（退出码 1）"""


class EnvError(Exception):
    """前置或环境错误（退出码 2）"""


# --------------------------------------------------------------------- 仓库定位


def _main_worktree_of(start: Path):
    """借 git 反查「主工作树」路径——脚本可能被从任务工作树里调用，不能只靠 __file__"""
    for extra in (["--path-format=absolute"], []):
        r = subprocess.run(
            ["git", "-C", str(start), "rev-parse", *extra, "--git-common-dir"],
            capture_output=True, text=True, encoding="utf-8", errors="replace",
            stdin=subprocess.DEVNULL,
        )
        if r.returncode == 0 and r.stdout.strip():
            common = Path(r.stdout.strip())
            if not common.is_absolute():
                common = (start / common).resolve()
            return common.parent if common.name == ".git" else common
    return None


_SCRIPT_ROOT = Path(__file__).resolve().parents[4]
REPO_ROOT = _main_worktree_of(_SCRIPT_ROOT) or _SCRIPT_ROOT
WT_ROOT = Path(os.environ.get("DTU_WT_ROOT") or (REPO_ROOT.parent / "_wt"))
BASE_BRANCH = os.environ.get("DTU_TASK_BASE", "v2-on-ui")

STATE_DIR = WT_ROOT / ".state"
LOCKS_DIR = STATE_DIR / "locks"


# --------------------------------------------------------------------- 基础工具


def git(*args, cwd=None, check=True, env=None):
    cmd = ["git"] + [str(a) for a in args]
    full_env = dict(os.environ)
    if env:
        full_env.update(env)
    r = subprocess.run(
        cmd, cwd=str(cwd or REPO_ROOT), capture_output=True, text=True,
        encoding="utf-8", errors="replace", stdin=subprocess.DEVNULL, env=full_env,
    )
    if check and r.returncode != 0:
        raise Fail("git {} 失败（rc={}）\n{}".format(
            " ".join(cmd[1:]), r.returncode, (r.stdout + r.stderr).strip()))
    return r


def git_out(*args, **kw):
    return git(*args, **kw).stdout.strip()


def worktree_entries():
    out = git_out("worktree", "list", "--porcelain")
    entries, cur = [], None
    for line in out.splitlines():
        if line.startswith("worktree "):
            if cur:
                entries.append(cur)
            cur = {"path": Path(line[len("worktree "):]), "branch": None}
        elif cur is None:
            continue
        elif line.startswith("branch refs/heads/"):
            cur["branch"] = line[len("branch refs/heads/"):]
    if cur:
        entries.append(cur)
    return entries


def main_worktree() -> Path:
    """集成点（合并发生的地方）。默认 = 主工作树；可用环境变量覆盖，便于演练/测试。"""
    override = os.environ.get("DTU_INTEGRATION_WORKTREE")
    if override:
        p = Path(override)
        if not p.is_absolute():
            p = (REPO_ROOT / p).resolve()
        if not p.is_dir():
            raise EnvError("DTU_INTEGRATION_WORKTREE 不存在：{}".format(p))
        return p
    entries = worktree_entries()
    if not entries:
        raise EnvError("无法解析 git worktree 列表")
    return entries[0]["path"]


def venv_python(tree: Path = None) -> Path:
    """优先用该工作树自己的 .venv（任务树里是指向主树的联接），否则退回主工作树"""
    for root in (tree, REPO_ROOT):
        if root is None:
            continue
        p = Path(root) / ".venv" / "Scripts" / "python.exe"
        if p.is_file():
            return p
    return Path(sys.executable)


def run_script(script: str, args, cwd: Path, label: str, tail: int = 40) -> bool:
    """跑项目脚本并回报。输出可能上千行，只回显尾部（结论与报错都在尾部）

    ⚠ 脚本必须取自 **cwd 那棵树**，不能固定用 REPO_ROOT：
    项目脚本普遍以 `__file__` 反推仓库根（如 `scripts/ci_local.py`、
    `scripts/check_registration.py`），若拿主树的脚本、却给集成树的 cwd，
    脚本仍会去校验主树——门禁就测错了对象（2026-10-12 实测踩到：
    报出主树才有的 iec104 未注册缺口，而集成树里根本没那些文件）。
    """
    script_path = Path(cwd) / script
    if not script_path.is_file():
        script_path = REPO_ROOT / script
    cmd = [str(venv_python(Path(cwd))), str(script_path)] + [str(x) for x in args]
    r = subprocess.run(
        cmd, cwd=str(cwd), capture_output=True, text=True,
        encoding="utf-8", errors="replace", stdin=subprocess.DEVNULL,
    )
    out = (r.stdout + r.stderr).strip()
    print("[{}] {}".format("ok" if r.returncode == 0 else "!!", label))
    if out:
        lines = out.splitlines()
        if len(lines) > tail:
            print("    …（前 {} 行略）".format(len(lines) - tail))
            lines = lines[-tail:]
        print("    " + "\n    ".join(lines))
    return r.returncode == 0


# --------------------------------------------------------------------- 台账


def state_file(task_id: str) -> Path:
    return STATE_DIR / (task_id + ".json")


def load_state(task_id: str) -> dict:
    p = state_file(task_id)
    if not p.is_file():
        raise EnvError("任务 {} 不存在（缺台账 {}）".format(task_id, p))
    return json.loads(p.read_text(encoding="utf-8"))


def save_state(st: dict) -> None:
    STATE_DIR.mkdir(parents=True, exist_ok=True)
    state_file(st["id"]).write_text(
        json.dumps(st, ensure_ascii=False, indent=2) + "\n", encoding="utf-8")


def all_states():
    if not STATE_DIR.is_dir():
        return []
    out = []
    for p in sorted(STATE_DIR.glob("*.json")):
        try:
            out.append(json.loads(p.read_text(encoding="utf-8")))
        except Exception:
            continue
    return out


# --------------------------------------------------------------------- 独占锁


def lock_age_hours(info) -> float:
    try:
        return max(0.0, (time.time() - float(info.get("epoch") or 0)) / 3600.0)
    except (TypeError, ValueError):
        return float("inf")


def lock_path(name: str) -> Path:
    return LOCKS_DIR / (name + ".lock")


def lock_read(name: str):
    p = lock_path(name)
    if not p.is_file():
        return None
    try:
        return json.loads(p.read_text(encoding="utf-8"))
    except Exception:
        return {"task": "?", "pid": 0, "epoch": 0, "at": "?"}


def lock_acquire(name: str, task: str, wait: int = 0, force: bool = False, note: str = ""):
    """抢占独占资源。

    ⚠ 锁**不**绑定进程存活：`lock acquire` 本身是短命进程，而用锁的烧录/构建
    在另一个进程里跑。因此判「陈旧」只看**时效**（超过 LOCK_TTL_HOURS），
    外加显式 `--force`；pid 仅作记录便于排障。
    """
    LOCKS_DIR.mkdir(parents=True, exist_ok=True)
    p = lock_path(name)
    deadline = time.time() + max(0, wait)
    while True:
        try:
            fd = os.open(str(p), os.O_CREAT | os.O_EXCL | os.O_WRONLY)
        except FileExistsError:
            info = lock_read(name) or {}
            if info.get("task") == task:
                return True, info
            age = lock_age_hours(info)
            if force or age > LOCK_TTL_HOURS:
                print("[lock] 接管 {} 锁（原持有者 {}，已持有 {:.1f} 小时{}）".format(
                    name, info.get("task"), age, "，--force" if force else "，视为陈旧"))
                try:
                    p.unlink()
                except OSError:
                    pass
                continue
            if time.time() >= deadline:
                return False, info
            print("[lock] {} 被 {} 占用（已持有 {:.1f} 小时），等待…".format(
                name, info.get("task"), age))
            time.sleep(2)
        else:
            now = time.time()
            payload = {
                "name": name, "task": task, "pid": os.getpid(),
                "host": os.environ.get("COMPUTERNAME", "?"),
                "epoch": now,
                "at": time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(now)),
                "note": note,
            }
            os.write(fd, (json.dumps(payload, ensure_ascii=False) + "\n").encode("utf-8"))
            os.close(fd)
            return True, payload


def lock_release(name: str, task=None, force: bool = False):
    p = lock_path(name)
    if not p.is_file():
        return True, "锁 {} 未被持有".format(name)
    info = lock_read(name) or {}
    if not force and task and info.get("task") not in (task, None):
        return False, "锁 {} 由 {} 持有，与 {} 不符；强制释放请加 --force".format(
            name, info.get("task"), task)
    try:
        p.unlink()
    except OSError as e:
        return False, "释放锁 {} 失败：{}".format(name, e)
    return True, "已释放锁 {}（原持有者 {}）".format(name, info.get("task"))


# --------------------------------------------------------------------- 目录联接


def is_reparse(p: Path) -> bool:
    try:
        st = os.lstat(str(p))
    except OSError:
        return False
    return bool(getattr(st, "st_file_attributes", 0) & FILE_ATTRIBUTE_REPARSE_POINT)


def make_junction(link: Path, target: Path) -> None:
    """创建 Windows 目录联接（不需要管理员权限，也不是符号链接）

    走 `mklink /J`——这是唯一不需要 SeCreateSymbolicLinkPrivilege 的目录链接形式。
    ⚠ 实测（2026-10-12）：直接用 ctypes 调 `DeviceIoControl(FSCTL_SET_REPARSE_POINT)`
    会被系统拒绝（Win32 4392 / ERROR_REPARSE_TAG_INVALID，缓冲区经 hexdump 核对无误），
    而 `mklink /J` 正常，故采用后者。参数以**列表**交给 subprocess，
    含空格的路径（本项目 `DTU Code`）由 subprocess 自动加引号，不经手写引号。
    """
    if os.name != "nt":
        raise EnvError("目录联接是 Windows 专属能力；当前平台 {}".format(os.name))
    if os.path.lexists(str(link)):
        raise Fail("联接位置已被占用：{}".format(link))
    if not target.exists():
        raise Fail("联接源不存在：{}".format(target))
    link.parent.mkdir(parents=True, exist_ok=True)
    r = subprocess.run(
        ["cmd", "/c", "mklink", "/J", str(link), str(target)],
        capture_output=True, stdin=subprocess.DEVNULL,
    )
    if r.returncode != 0 or not is_reparse(link):
        detail = (r.stdout or b"").decode("mbcs", "replace").strip()
        raise Fail("创建目录联接失败：{} -> {}\n  rc={}  {}".format(
            link, target, r.returncode, detail))


def remove_junction(link: Path) -> bool:
    """只摘掉联接本身，绝不触碰目标内容（os.rmdir = RemoveDirectoryW）"""
    if not is_reparse(link):
        return False
    try:
        os.rmdir(str(link))
        return True
    except OSError as e:
        print("[warn] 摘除联接失败 {}：{}".format(link, e))
        return False


def bootstrap(wt: Path):
    """建立共享联接。单个联接失败只告警不中止——避免留下半成品任务空间"""
    made, failed = [], []
    for rel, desc in JUNCTION_SPECS:
        target = REPO_ROOT / rel
        if not target.exists():
            print("[skip] {}（{}）不存在，跳过联接".format(rel, desc))
            continue
        try:
            make_junction(wt / rel, target)
        except (Fail, EnvError) as e:
            failed.append(rel)
            print("[WARN] {} 联接失败：{}".format(rel, e))
            continue
        made.append(rel)
        print("[ok]   联接 {} -> {}".format(rel, target))
    if failed:
        print()
        print("!! {} 个共享联接未建成；该任务里跑 `.venv\\Scripts\\python.exe` 会找不到解释器。".format(len(failed)))
        for rel in failed:
            print("   手工补：cmd /c mklink /J \"{}\\{}\" \"{}\\{}\"".format(wt, rel, REPO_ROOT, rel))
    return made


# --------------------------------------------------------------------- 子进程脚本


def regen(cwd: Path) -> None:
    run_script("scripts/gen_task_table.py", ["--write"], cwd, "重生成 FreeRTOS 任务表")
    if list((Path(cwd) / "MDK-ARM").glob("**/*.map")):
        run_script("scripts/check_mem_numbers.py", ["--write"], cwd, "同步内存/Flash 快照")
    else:
        print("[skip] 未找到 .map，跳过内存快照同步（需先 @build）")


def run_gates(cwd: Path, skip_build: bool) -> bool:
    ok = run_script("scripts/ci_local.py", [], cwd, "L0 + L0.5 本地等价 CI")
    if skip_build:
        print("[skip] 按 --skip-build 跳过 @build")
        return ok
    got, info = lock_acquire("build", "__done__", wait=900)
    if not got:
        print("!! build 锁被 {} 占用（UV4 不能并发构建），跳过 @build".format(info.get("task")))
        return False
    try:
        if not run_script(".dsh/skills/keil-build/scripts/keil_build.py", [], cwd,
                          "@build（0 错 0 警）"):
            ok = False
    finally:
        lock_release("build", "__done__", force=True)
    return ok


# --------------------------------------------------------------------- 合并辅助


def write_merge_message(st: dict, base: str, cwd: Path) -> Path:
    raw = git_out("log", "--format=%s", "{}..{}".format(base, st["branch"]), cwd=cwd)
    subjects = [s.strip() for s in raw.splitlines() if s.strip()]
    title = "merge: {} 合入 {}".format(st["branch"], base)
    if len(title) > 100:
        title = title[:97] + "..."
    lines = [title, "", "任务 {}（{} 个提交）经 task-worktree 回收：".format(st["id"], len(subjects))]
    for s in subjects:
        lines.append("- " + (s[:73] + "..." if len(s) > 76 else s))
    if st.get("note"):
        note = st["note"]
        lines.append("")
        lines.append("备注：" + (note[:73] + "..." if len(note) > 76 else note))
    fd, path = tempfile.mkstemp(prefix="taskwt-merge-", suffix=".txt")
    os.close(fd)
    Path(path).write_text("\n".join(lines) + "\n", encoding="utf-8", newline="\n")
    return Path(path)


def audit_residue(base_before: str, branch: str, cwd: Path) -> None:
    """并集合并残留审计：双方都改过的文件会被 git 自动并成并集"""
    mb = git_out("merge-base", base_before, branch, cwd=cwd)
    task_files = set(filter(None, git_out("diff", "--name-only", mb, branch, cwd=cwd).splitlines()))
    base_files = set(filter(None, git_out("diff", "--name-only", mb, base_before, cwd=cwd).splitlines()))
    both = sorted(task_files & base_files)
    if not both:
        print("[ok] 没有「双方都改过」的文件，无并集残留风险")
        return
    print("以下 {} 个文件双方都改过，git 会自动并成并集，需人工核对：".format(len(both)))
    for f in both[:30]:
        print("  - " + f)
    if len(both) > 30:
        print("  …（其余 {} 个略）".format(len(both) - 30))
    hits = []
    for f in both:
        p = cwd / f
        if not p.is_file():
            continue
        try:
            lines = p.read_text(encoding="utf-8", errors="replace").splitlines()
        except OSError:
            continue
        dups = [i + 1 for i in range(1, len(lines))
                if lines[i] == lines[i - 1] and lines[i].strip()]
        if dups:
            hits.append((f, dups))
    if hits:
        print()
        print("!! 连续重复行（并集合并残留嫌疑）：")
        for f, dups in hits:
            print("  - {} 第 {} 行".format(f, ", ".join(str(d) for d in dups[:8])))
    else:
        print("[ok] 未检测到连续重复行")
    print("提示：权威判据是 base / 两个 tip 三方对比（git show <ref>:<file>），别只看结果文件。")


def harvest_memory(st: dict) -> None:
    """任务工作树会被删除，先把它自己的记忆归并回主工作树，避免丢上下文"""
    src = Path(st["path"]) / ".workbuddy-ai" / "memory"
    if not src.is_dir():
        return
    dst_dir = REPO_ROOT / ".workbuddy-ai" / "memory"
    dst_dir.mkdir(parents=True, exist_ok=True)
    for f in sorted(src.glob("*.md")):
        text = f.read_text(encoding="utf-8", errors="replace").strip()
        if not text:
            continue
        dst = dst_dir / f.name
        marker = "## [task-worktree 归并自任务 {} / {}]".format(st["id"], st["slug"])
        with dst.open("a", encoding="utf-8", newline="\n") as fh:
            fh.write("\n" + marker + "\n\n" + text + "\n")
        print("[ok]   记忆归并 {} -> {}".format(f.name, dst))


def teardown_worktree(st: dict, force: bool = False, base: str = None) -> None:
    wt = Path(st["path"])
    base = base or st.get("base")
    # 1) 先摘联接——绝不能让 git 递归进联接去删目标内容（.venv / SDL2 会被一起删掉）
    for rel in st.get("junctions", []):
        if remove_junction(wt / rel):
            print("[ok]   已摘除联接 {}".format(rel))
    # 2) 归并任务侧记忆
    if wt.is_dir():
        harvest_memory(st)
    # 3) 移除工作树
    r = git("worktree", "remove", *(["--force"] if force else []), str(wt), check=False)
    if r.returncode != 0:
        raise Fail("移除工作树失败：{}\n（提示：先处理未跟踪文件，或加 --force）".format(
            (r.stdout + r.stderr).strip()))
    # 4) 删分支。⚠ 不用 `git branch -d`——它按**环境 HEAD** 判断是否已合并，
    #    集成点被 DTU_INTEGRATION_WORKTREE 改走时会误判。改为显式核对 base。
    if force or git("merge-base", "--is-ancestor", st["branch"], base,
                    check=False).returncode == 0:
        r = git("branch", "-D", st["branch"], check=False)
        if r.returncode != 0:
            print("[warn] 删除分支 {} 失败：{}".format(
                st["branch"], (r.stdout + r.stderr).strip()))
        else:
            print("[ok]   已删除分支 {}".format(st["branch"]))
    else:
        print("[warn] 分支 {} 未并入 {}，保留不删（确认可弃再 `git branch -D {}`）".format(
            st["branch"], base, st["branch"]))
    state_file(st["id"]).unlink(missing_ok=True)


# --------------------------------------------------------------------- 子命令


def cmd_new(a) -> int:
    if not ID_RE.match(a.task_id):
        raise EnvError("任务 ID 非法：{}（字母数字开头，可用 . _ -）".format(a.task_id))
    if not SLUG_RE.match(a.slug):
        raise EnvError("slug 非法：{}（小写字母数字与连字符）".format(a.slug))
    branch = "{}{}-{}".format(BRANCH_PREFIX, a.task_id, a.slug)
    wt = WT_ROOT / "{}-{}".format(a.task_id, a.slug)

    if state_file(a.task_id).is_file():
        raise EnvError("任务 {} 已存在（{}）".format(a.task_id, state_file(a.task_id)))
    if os.path.lexists(str(wt)):
        raise EnvError("目录已存在：{}".format(wt))
    if git("rev-parse", "--verify", "--quiet", "refs/heads/" + branch, check=False).returncode == 0:
        raise EnvError("分支已存在：{}".format(branch))
    if git("rev-parse", "--verify", "--quiet", a.base, check=False).returncode != 0:
        raise EnvError("基线分支不存在：{}".format(a.base))

    active = [s for s in all_states() if Path(s["path"]).is_dir()]
    if len(active) >= MAX_CONCURRENT and not a.force:
        raise EnvError("已有 {} 个活跃任务（上限 {}）；先 done/abort，或加 --force".format(
            len(active), MAX_CONCURRENT))

    WT_ROOT.mkdir(parents=True, exist_ok=True)
    print("[1/3] 建工作树（分支 {}，基线 {}{}）…".format(
        branch, a.base, "，跳过 LFS smudge" if a.lean else ""))
    git("worktree", "add", "-b", branch, str(wt), a.base,
        env={"GIT_LFS_SKIP_SMUDGE": "1"} if a.lean else None)

    print("[2/3] 建立共享联接…")
    junctions = [] if a.no_bootstrap else bootstrap(wt)

    st = {
        "id": a.task_id, "slug": a.slug, "branch": branch, "path": str(wt),
        "base": a.base, "created_at": time.strftime("%Y-%m-%d %H:%M:%S"),
        "junctions": junctions, "needs_bench": bool(a.needs_bench),
        "bench_pass": False, "note": a.note or "", "lean": bool(a.lean),
    }
    save_state(st)
    print("[3/3] 台账已写入 {}".format(state_file(a.task_id)))
    print()
    print("下一步：把新会话的工作目录切到")
    print("  " + str(wt))
    print("在该目录里干活、跑 @build 与 ci_local.py（并行安全）；")
    print("要动台架先 `lock acquire bench --task {}`，完事 `lock release bench --task {} --bench-pass`。".format(
        a.task_id, a.task_id))
    print("回收用 `done {}`（**必须在主工作树执行**）。".format(a.task_id))
    return EXIT_OK


def cmd_list(a) -> int:
    states = all_states()
    if not states:
        print("（没有任务空间。用 `new <ID> <slug>` 建一个）")
        return EXIT_OK
    print("{:<12} {:<32} {:>5} {:>5} {:>4}  {}".format(
        "任务", "分支", "落后", "领先", "脏", "台架"))
    for st in states:
        wt = Path(st["path"])
        if not wt.is_dir():
            print("{:<12} {:<32} {:>5} {:>5} {:>4}  {}".format(
                st["id"], st["branch"], "-", "-", "-", "[工作树缺失]"))
            continue
        ab = git_out("rev-list", "--left-right", "--count",
                     "{}...{}".format(st["base"], st["branch"]), cwd=wt, check=False).split()
        behind, ahead = (ab[0], ab[1]) if len(ab) == 2 else ("?", "?")
        dirty = len(git_out("status", "--porcelain", cwd=wt, check=False).splitlines())
        bench = "PASS" if st.get("bench_pass") else ("需测" if st.get("needs_bench") else "-")
        print("{:<12} {:<32} {:>5} {:>5} {:>4}  {}".format(
            st["id"], st["branch"], behind, ahead, dirty, bench))
    print()
    for n in LOCK_NAMES:
        info = lock_read(n)
        if not info:
            print("锁 {:<6} 空闲".format(n))
        else:
            print("锁 {:<6} {} 持有（已 {:.1f} 小时，于 {}）".format(
                n, info.get("task"), lock_age_hours(info), info.get("at")))
    return EXIT_OK


def cmd_status(a) -> int:
    st = load_state(a.task_id)
    wt = Path(st["path"])
    print("任务      {}  ({})".format(st["id"], st["slug"]))
    print("分支      {}  ←  基线 {}".format(st["branch"], st["base"]))
    print("工作树    {}{}".format(wt, "" if wt.is_dir() else "   [缺失]"))
    print("建立于    {}".format(st.get("created_at")))
    if st.get("note"):
        print("备注      {}".format(st["note"]))
    if wt.is_dir():
        dirty = git_out("status", "--porcelain", cwd=wt, check=False).splitlines()
        print("未提交    {} 项".format(len(dirty)))
        for line in dirty[:10]:
            print("            " + line)
        ab = git_out("rev-list", "--left-right", "--count",
                     "{}...{}".format(st["base"], st["branch"]), cwd=wt, check=False).split()
        if len(ab) == 2:
            print("相对基线  落后 {} / 领先 {} 个提交".format(ab[0], ab[1]))
    print("台架      {}{}".format(
        "需要，" if st.get("needs_bench") else "不涉及，",
        "已记录 PASS" if st.get("bench_pass") else "尚无 PASS 记录"))
    if st.get("junctions"):
        print("联接      {}".format(", ".join(st["junctions"])))
    return EXIT_OK


def cmd_sync(a) -> int:
    st = load_state(a.task_id)
    wt = Path(st["path"])
    base = a.base or st["base"]
    if not wt.is_dir():
        raise EnvError("工作树不存在：{}".format(wt))
    if git_out("status", "--porcelain", cwd=wt, check=False):
        raise Fail("任务工作树有未提交改动，先提交或 stash 再 sync")
    r = git("rebase", base, cwd=wt, check=False)
    if r.returncode != 0:
        print((r.stdout + r.stderr).strip())
        raise Fail("rebase 有冲突：在 {} 里解决后 `git rebase --continue`，放弃用 `git rebase --abort`".format(wt))
    print("[ok] 任务 {} 已 rebase 到 {}".format(st["id"], base))
    return EXIT_OK


def cmd_lock(a) -> int:
    if a.action == "status":
        for n in LOCK_NAMES:
            info = lock_read(n)
            if not info:
                print("{:<6} 空闲".format(n))
            else:
                age = lock_age_hours(info)
                mark = "  [陈旧，可被自动接管]" if age > LOCK_TTL_HOURS else ""
                print("{:<6} {} 持有（pid={}，于 {}，已 {:.1f} 小时，备注 {}）{}".format(
                    n, info.get("task"), info.get("pid"), info.get("at"), age,
                    info.get("note") or "-", mark))
        return EXIT_OK

    if a.name not in LOCK_NAMES:
        raise EnvError("未知资源 {}（可用：{}）".format(a.name, " / ".join(LOCK_NAMES)))

    if a.action == "acquire":
        if not a.task:
            raise EnvError("acquire 需要 --task <ID>")
        got, info = lock_acquire(a.name, a.task, wait=a.wait, force=a.force, note=a.note or "")
        if not got:
            print("获取失败：{} 被 {} 占用（pid={}，于 {}）".format(
                a.name, info.get("task"), info.get("pid"), info.get("at")))
            return EXIT_FAIL
        print("已获取 {} 锁（task={} pid={}）".format(a.name, a.task, os.getpid()))
        return EXIT_OK

    if a.bench_pass:
        if not a.task:
            raise EnvError("--bench-pass 需要 --task <ID>")
        st = load_state(a.task)
        st["bench_pass"] = True
        save_state(st)
        print("[ok] 已为任务 {} 记录台架 PASS".format(a.task))
    ok, msg = lock_release(a.name, a.task, force=a.force)
    print(msg)
    return EXIT_OK if ok else EXIT_FAIL


def cmd_done(a) -> int:
    st = load_state(a.task_id)
    wt = Path(st["path"])
    branch = st["branch"]
    base = a.base or st["base"]
    main = main_worktree()

    print("=== 前置检查 ===")
    if not wt.is_dir():
        raise EnvError("工作树不存在：{}".format(wt))
    if git_out("status", "--porcelain", cwd=wt, check=False):
        raise Fail("任务工作树有未提交改动，先提交")
    if git_out("status", "--porcelain", cwd=main, check=False):
        raise Fail("主工作树不干净（{}）——合并会把未提交改动卷进来".format(main))
    cur = git_out("rev-parse", "--abbrev-ref", "HEAD", cwd=main)
    if cur != base:
        raise Fail("主工作树当前在 {}，不是集成分支 {}；先切过去再 done".format(cur, base))
    for n in LOCK_NAMES:
        info = lock_read(n)
        if info:
            raise Fail("独占资源 {} 仍被 {} 占用（已 {:.1f} 小时），先 release".format(
                n, info.get("task"), lock_age_hours(info)))

    ahead = int(git_out("rev-list", "--count", "{}..{}".format(base, branch), cwd=wt) or "0")
    already = git("merge-base", "--is-ancestor", branch, base, cwd=main, check=False).returncode == 0
    if ahead == 0 and not already:
        raise Fail("任务分支相对 {} 没有新提交，无需合并".format(base))
    if already and ahead == 0:
        print("[i] {} 已合入 {}，跳过合并，直接清场".format(branch, base))
        print("=== 清场 ===")
        teardown_worktree(st, force=a.force, base=base)
        print("\n完成（分支此前已合入）。")
        return EXIT_OK

    if st.get("needs_bench") and not st.get("bench_pass"):
        raise Fail("任务标记 --needs-bench 但无台架 PASS 记录；跑完 @test 后执行 "
                   "`lock release bench --task {} --bench-pass`".format(st["id"]))
    print("[ok] 前置检查通过（领先 {} 共 {} 个提交）".format(base, ahead))

    print("=== 合并预演（git merge-tree，不改动任何东西）===")
    r = git("merge-tree", "--write-tree", base, branch, cwd=main, check=False)
    if r.returncode != 0:
        print((r.stdout + r.stderr).strip())
        raise Fail("预演发现冲突：到任务工作树里 `git merge {}` 解决并提交后重跑 done".format(base))
    tree = (r.stdout.splitlines() or ["?"])[0].strip()
    print("[ok] 无冲突，预演结果树 {}".format(tree))
    if a.dry_run:
        print()
        print("--dry-run：到此为止，未做任何改动。")
        return EXIT_OK

    print("=== 合入主干（{}，--no-ff）===".format(main))
    base_before = git_out("rev-parse", "HEAD", cwd=main)
    msgfile = write_merge_message(st, base, wt)
    r = git("merge", "--no-ff", "--no-edit", branch, "-F", str(msgfile), cwd=main, check=False)
    msgfile.unlink(missing_ok=True)
    if r.returncode != 0:
        raise Fail("合并失败：\n{}".format((r.stdout + r.stderr).strip()))
    print((r.stdout or "").strip())
    base_after = git_out("rev-parse", "HEAD", cwd=main)

    print("=== 合并残留审计 ===")
    audit_residue(base_before, branch, cwd=main)

    print("=== 重生成受管产物 ===")
    regen(main)

    if a.skip_gates:
        print("=== 门禁（--skip-gates 已跳过）===")
        gates_ok = True
    else:
        print("=== 门禁 ===")
        gates_ok = run_gates(main, skip_build=a.skip_build)

    if not gates_ok:
        print()
        print("!! 门禁未全绿：工作树与分支**保留**，未清场。")
        print("   主干已含合并提交 {}".format(base_after[:12]))
        print("   可选：a) 在主工作树修正后追加提交（推荐）")
        print("         b) 回退本次合并：git -C \"{}\" reset --hard {}".format(main, base_before[:12]))
        return EXIT_FAIL

    print("=== 清场 ===")
    teardown_worktree(st, force=a.force, base=base)
    print()
    print("完成。主干 {} 现为 {}。".format(base, base_after[:12]))
    print("push 需人工许可，本次未推送。")
    return EXIT_OK


def cmd_abort(a) -> int:
    st = load_state(a.task_id)
    wt = Path(st["path"])
    if wt.is_dir():
        dirty = git_out("status", "--porcelain", cwd=wt, check=False).splitlines()
        ahead = int(git_out("rev-list", "--count",
                            "{}..{}".format(st["base"], st["branch"]), cwd=wt,
                            check=False) or "0")
        if (dirty or ahead) and not a.force:
            print("任务 {} 有 {} 项未提交改动、{} 个未合并提交，abort 会**永久丢弃**：".format(
                st["id"], len(dirty), ahead))
            for line in dirty[:20]:
                print("  " + line)
            raise Fail("确认丢弃请加 --force")
    teardown_worktree(st, force=True)
    print("\n已放弃任务 {}（工作树与分支均已删除）".format(st["id"]))
    return EXIT_OK


# --------------------------------------------------------------------- 入口


def build_parser():
    ap = argparse.ArgumentParser(
        prog="task_worktree.py",
        description="多任务并行开发的空间管理（git worktree 生命周期）")
    sub = ap.add_subparsers(dest="cmd")

    p = sub.add_parser("new", help="新建任务空间")
    p.add_argument("task_id")
    p.add_argument("slug")
    p.add_argument("--base", default=BASE_BRANCH, help="基线分支（默认 %(default)s）")
    p.add_argument("--lean", action="store_true",
                   help="跳过 Git LFS smudge（省约 38MB，参考图变成指针文件）")
    p.add_argument("--no-bootstrap", action="store_true", help="不建共享联接")
    p.add_argument("--needs-bench", action="store_true",
                   help="需台架验证；无 PASS 记录则 done 拒绝合并")
    p.add_argument("--note", default="")
    p.add_argument("--force", action="store_true", help="忽略并发上限")
    p.set_defaults(func=cmd_new)

    p = sub.add_parser("list", help="列出所有任务空间")
    p.set_defaults(func=cmd_list)

    p = sub.add_parser("status", help="单个任务详情")
    p.add_argument("task_id")
    p.set_defaults(func=cmd_status)

    p = sub.add_parser("sync", help="rebase 追平主干")
    p.add_argument("task_id")
    p.add_argument("--base", default=None)
    p.set_defaults(func=cmd_sync)

    p = sub.add_parser("lock", help="独占资源锁（build / bench）")
    p.add_argument("action", choices=["acquire", "release", "status"])
    p.add_argument("name", nargs="?", choices=list(LOCK_NAMES))
    p.add_argument("--task", default=None)
    p.add_argument("--wait", type=int, default=0, help="等待秒数（0=不等待）")
    p.add_argument("--force", action="store_true")
    p.add_argument("--note", default="")
    p.add_argument("--bench-pass", action="store_true",
                   help="release bench 时顺带为该任务记录台架 PASS")
    p.set_defaults(func=cmd_lock)

    p = sub.add_parser("done", help="回收：预演 → 合入主干 → 审计 → 重生成 → 门禁 → 清场")
    p.add_argument("task_id")
    p.add_argument("--base", default=None)
    p.add_argument("--dry-run", action="store_true", help="只预演，不做任何改动")
    p.add_argument("--skip-build", action="store_true", help="跳过 @build")
    p.add_argument("--skip-gates", action="store_true", help="跳过全部门禁")
    p.add_argument("--force", action="store_true", help="清场时强制移除工作树")
    p.set_defaults(func=cmd_done)

    p = sub.add_parser("abort", help="放弃任务（不合并）")
    p.add_argument("task_id")
    p.add_argument("--force", action="store_true")
    p.set_defaults(func=cmd_abort)
    return ap


def main(argv=None) -> int:
    ap = build_parser()
    a = ap.parse_args(argv)
    if not getattr(a, "func", None):
        ap.print_help()
        return EXIT_USAGE
    if not (REPO_ROOT / ".git").exists():
        print("!! 无法定位仓库根（推导为 {}）".format(REPO_ROOT), file=sys.stderr)
        return EXIT_ENV
    try:
        return a.func(a)
    except EnvError as e:
        print("前置/环境错误：{}".format(e), file=sys.stderr)
        return EXIT_ENV
    except Fail as e:
        print("失败：{}".format(e), file=sys.stderr)
        return EXIT_FAIL
    except KeyboardInterrupt:
        print("已中断", file=sys.stderr)
        return EXIT_FAIL


if __name__ == "__main__":
    sys.exit(main())