"""
pipeline_service/deploy_account.py - 应用部署主机逻辑账号系统

每个平台用户默认拥有一个逻辑部署账号（ag_ 前缀），实现：
1. 隔离部署目录（零 root，不建真实 Linux 账号）
2. 免密访问（部署进程直接文件系统读写，无需 SSH/密码）
3. bwrap 沙箱执行（user namespace 隔离文件/进程/IPC/UTS）
4. 特权能力（沙箱内 root-like 映射，受 user namespace 约束）

全程零 root：运行时不 sudo、不 useradd，仅依赖 bwrap（unprivileged user namespaces）。
"""

import os
import re
import json
import shutil
import asyncio
import logging

logger = logging.getLogger("pipeline.deploy_account")

# 部署账号根目录
DEPLOY_ENV_BASE = "/d/pipeline/deploy_envs"

# bwrap 可执行文件（未安装时为 None，降级为目录隔离）
# 检测顺序：系统 PATH → 环境变量 → 已知安装位置
BWRAP = shutil.which("bwrap")
for _p in (
    os.environ.get("BWRAP_PATH", ""),
    "/d/pipeline/bin/bwrap",
    "/d/pipeline/pipeline-app/bin/bwrap",
):
    if not BWRAP and _p and os.path.exists(_p):
        BWRAP = _p

# 账号名合法字符（目录安全，防路径穿越）
_SAFE_RE = re.compile(r"[^a-zA-Z0-9_-]")


def sanitize_username(username: str) -> str:
    """把用户 username 清洗成安全的账号名片段。"""
    s = _SAFE_RE.sub("_", username or "").strip("_")
    return s or "user"


def account_name_for(username: str) -> str:
    """生成账号名：ag_<username>。"""
    return f"ag_{sanitize_username(username)}"


def deploy_dir_for(account_name: str) -> str:
    """账号隔离目录。"""
    return os.path.join(DEPLOY_ENV_BASE, account_name)


def _ensure_account_dirs(account_name: str) -> str:
    """创建账号目录结构，返回 deploy_dir。幂等。"""
    d = deploy_dir_for(account_name)
    for sub in ("", "home", "workspace", "data", "logs"):
        os.makedirs(os.path.join(d, sub), exist_ok=True)
    return d


def _resolve_deploy_dir(sor, account_name):
    """从 DB 查 deploy_dir，无记录则返回 None。"""
    return deploy_dir_for(account_name)


def _is_safe_relpath(relpath: str) -> bool:
    """防路径穿越：相对路径不得包含 .. 或绝对路径。"""
    if not relpath:
        return True
    if relpath.startswith("/") or relpath.startswith("\\"):
        return False
    if ".." in relpath.split("/"):
        return False
    return True


# ═══════════════════════════════════════════════════════════
# 账号管理
# ═══════════════════════════════════════════════════════════

async def ensure_account(sor, user_id: str, username: str) -> dict:
    """确保用户拥有逻辑部署账号。幂等：已存在则返回现有记录。

    Returns: {"account_name": str, "deploy_dir": str, "created": bool}
    """
    account_name = account_name_for(username)

    # 查现有记录
    recs = await sor.sqlExe(
        "SELECT id, account_name, deploy_dir, status FROM sd_deploy_accounts "
        "WHERE user_id=${uid}$ LIMIT 1", {"uid": user_id})
    if recs:
        r = recs[0]
        deploy_dir = getattr(r, "deploy_dir", "") or deploy_dir_for(account_name)
        _ensure_account_dirs(account_name)
        return {
            "account_name": getattr(r, "account_name", account_name),
            "deploy_dir": deploy_dir,
            "created": False,
        }

    # 新建
    from appPublic.uniqueID import getID
    deploy_dir = _ensure_account_dirs(account_name)
    rec_id = getID()
    await sor.C("sd_deploy_accounts", {
        "id": rec_id,
        "user_id": user_id,
        "account_name": account_name,
        "deploy_dir": deploy_dir,
        "status": "active",
        "sandbox_config": json.dumps({"network": "shared", "readonly_system": True}),
    })
    logger.info("deploy account created: %s (%s)", account_name, user_id)
    return {"account_name": account_name, "deploy_dir": deploy_dir, "created": True}


async def remove_account(sor, account_name: str) -> dict:
    """删除逻辑账号（DB 记录 + 目录）。"""
    account_name = sanitize_username(account_name)
    if not account_name.startswith("ag_"):
        return {"ok": False, "error": "非法账号名"}

    recs = await sor.sqlExe(
        "SELECT deploy_dir FROM sd_deploy_accounts WHERE account_name=${n}$ LIMIT 1",
        {"n": account_name})
    if not recs:
        return {"ok": False, "error": "账号不存在"}

    deploy_dir = getattr(recs[0], "deploy_dir", "") or deploy_dir_for(account_name)

    # 删目录（限定在 DEPLOY_ENV_BASE 内，防误删）
    if deploy_dir.startswith(DEPLOY_ENV_BASE + "/") and os.path.isdir(deploy_dir):
        shutil.rmtree(deploy_dir, ignore_errors=True)

    await sor.sqlExe(
        "DELETE FROM sd_deploy_accounts WHERE account_name=${n}$", {"n": account_name})
    logger.info("deploy account removed: %s", account_name)
    return {"ok": True, "account_name": account_name}


async def list_accounts(sor, user_id: str = "") -> list:
    """列出部署账号。user_id 为空则列全部。"""
    if user_id:
        recs = await sor.sqlExe(
            "SELECT account_name, user_id, deploy_dir, status, created_at "
            "FROM sd_deploy_accounts WHERE user_id=${uid}$ ORDER BY created_at DESC",
            {"uid": user_id})
    else:
        recs = await sor.sqlExe(
            "SELECT account_name, user_id, deploy_dir, status, created_at "
            "FROM sd_deploy_accounts ORDER BY created_at DESC")
    out = []
    for r in recs:
        out.append({
            "account_name": getattr(r, "account_name", ""),
            "user_id": getattr(r, "user_id", ""),
            "deploy_dir": getattr(r, "deploy_dir", ""),
            "status": getattr(r, "status", ""),
            "created_at": str(getattr(r, "created_at", "")),
        })
    return out


# ═══════════════════════════════════════════════════════════
# 免密目录访问（部署进程直接读写，无需认证）
# ═══════════════════════════════════════════════════════════

async def write_file(sor, account_name: str, relpath: str, content: str) -> dict:
    """部署进程免密写入文件到账号目录。"""
    if not _is_safe_relpath(relpath):
        return {"ok": False, "error": "非法路径"}
    deploy_dir = _resolve_deploy_dir(sor, account_name)
    full = os.path.abspath(os.path.join(deploy_dir, relpath))
    if not full.startswith(deploy_dir + "/"):
        return {"ok": False, "error": "路径越界"}
    try:
        os.makedirs(os.path.dirname(full), exist_ok=True)
        with open(full, "w", encoding="utf-8") as f:
            f.write(content or "")
        return {"ok": True, "path": full}
    except Exception as e:
        return {"ok": False, "error": str(e)}


async def read_file(sor, account_name: str, relpath: str, limit: int = 20000) -> dict:
    """免密读取账号目录文件。"""
    if not _is_safe_relpath(relpath):
        return {"ok": False, "error": "非法路径"}
    deploy_dir = _resolve_deploy_dir(sor, account_name)
    full = os.path.abspath(os.path.join(deploy_dir, relpath))
    if not full.startswith(deploy_dir + "/"):
        return {"ok": False, "error": "路径越界"}
    try:
        with open(full, "r", encoding="utf-8", errors="replace") as f:
            content = f.read(limit)
        return {"ok": True, "content": content}
    except Exception as e:
        return {"ok": False, "error": str(e)}


async def list_dir(sor, account_name: str, relpath: str = "") -> dict:
    """免密列出账号目录。"""
    if not _is_safe_relpath(relpath):
        return {"ok": False, "error": "非法路径"}
    deploy_dir = _resolve_deploy_dir(sor, account_name)
    full = os.path.abspath(os.path.join(deploy_dir, relpath)) if relpath else deploy_dir
    if not full.startswith(deploy_dir + "/") and full != deploy_dir:
        return {"ok": False, "error": "路径越界"}
    try:
        entries = []
        for name in sorted(os.listdir(full)):
            p = os.path.join(full, name)
            entries.append({
                "name": name,
                "is_dir": os.path.isdir(p),
                "size": os.path.getsize(p) if os.path.isfile(p) else 0,
            })
        return {"ok": True, "entries": entries}
    except Exception as e:
        return {"ok": False, "error": str(e)}


# ═══════════════════════════════════════════════════════════
# bwrap 沙箱执行
# ═══════════════════════════════════════════════════════════

def _build_bwrap_cmd(deploy_dir: str, command: str, workdir: str = "", network: str = "shared") -> list:
    """构建 bwrap 命令。

    - 隔离 user/pid/ipc/uts namespace（保留网络，部署应用通常需要）
    - 只读挂载系统目录，可写挂载 deploy_dir
    - tmpfs /tmp（会话内隔离）
    """
    parts = [
        BWRAP,
        "--unshare-user", "--unshare-pid", "--unshare-ipc", "--unshare-uts",
        "--die-with-parent",
        "--ro-bind", "/usr", "/usr",
        "--ro-bind", "/bin", "/bin",
        "--ro-bind", "/sbin", "/sbin",
        "--ro-bind", "/lib", "/lib",
        "--ro-bind", "/lib64", "/lib64",
        "--ro-bind", "/etc", "/etc",
        "--proc", "/proc",
        "--dev", "/dev",
        "--tmpfs", "/tmp",
        "--bind", deploy_dir, "/home",
        "--setenv", "HOME", "/home",
    ]
    if network == "isolated":
        parts.insert(1, "--unshare-net")

    chdir = "/home"
    if workdir and _is_safe_relpath(workdir):
        chdir = "/home/" + workdir.strip("/")
    parts += ["--chdir", chdir, "--", "bash", "-c", command]
    return parts


async def run_in_sandbox(sor, account_name: str, command: str,
                         workdir: str = "", timeout: int = 120,
                         network: str = "shared") -> dict:
    """在账号沙箱内执行命令。返回 {rc, stdout, stderr, sandbox}。"""
    if not command:
        return {"rc": -1, "stdout": "", "stderr": "缺少命令", "sandbox": bool(BWRAP)}

    deploy_dir = _resolve_deploy_dir(sor, account_name)
    if not os.path.isdir(deploy_dir):
        return {"rc": -1, "stdout": "", "stderr": f"账号目录不存在: {deploy_dir}", "sandbox": bool(BWRAP)}

    if BWRAP:
        cmd = _build_bwrap_cmd(deploy_dir, command, workdir, network)
        # bwrap 用列表直接执行（非 shell，防注入）
        proc = await asyncio.create_subprocess_exec(
            *cmd, stdout=asyncio.subprocess.PIPE, stderr=asyncio.subprocess.PIPE)
    else:
        # 降级：无 bwrap，目录 + chdir 弱隔离
        cwd = os.path.join(deploy_dir, workdir) if workdir and _is_safe_relpath(workdir) else deploy_dir
        if not cwd.startswith(deploy_dir + "/") and cwd != deploy_dir:
            return {"rc": -1, "stdout": "", "stderr": "路径越界", "sandbox": False}
        proc = await asyncio.create_subprocess_shell(
            command, stdout=asyncio.subprocess.PIPE, stderr=asyncio.subprocess.PIPE, cwd=cwd)

    try:
        stdout, stderr = await asyncio.wait_for(proc.communicate(), timeout=timeout)
    except asyncio.TimeoutError:
        proc.kill()
        await proc.wait()
        return {"rc": -1, "stdout": "", "stderr": f"命令超时（{timeout}s）", "sandbox": bool(BWRAP)}

    return {
        "rc": proc.returncode or 0,
        "stdout": stdout.decode("utf-8", "replace")[-8000:],
        "stderr": stderr.decode("utf-8", "replace")[-4000:],
        "sandbox": bool(BWRAP),
    }