"""
Supervisor 多账号托管（宝塔插件兼容）

目标：
- 根据 account_id 自动生成一个 supervisor program 配置文件（.ini）
- 自动定位 supervisord.conf 的 include 目录（尽量不要求你手填路径）
- 提供 supervisorctl 的常用调用封装（reread/update/status/start/stop/restart）

重要说明：
- 本模块只写入“程序配置文件”，不包含任何 API Key/Secret
- trading_system 进程通过 ATS_ACCOUNT_ID 选择自己的账号配置
"""

from __future__ import annotations

import os
import re
import subprocess
import sys
from dataclasses import dataclass
from pathlib import Path
from typing import Optional, Tuple


DEFAULT_CANDIDATE_CONFS = [
    "/www/server/panel/plugin/supervisor/supervisord.conf",
    "/www/server/panel/plugin/supervisor/supervisor.conf",
    "/etc/supervisor/supervisord.conf",
    "/etc/supervisord.conf",
]

# 常见 supervisord 主日志路径候选（不同发行版/面板插件差异很大）
DEFAULT_SUPERVISORD_LOG_CANDIDATES = [
    # aaPanel / 宝塔 supervisor 插件常见
    "/www/server/panel/plugin/supervisor/log/supervisord.log",
    "/www/server/panel/plugin/supervisor/log/supervisor.log",
    "/www/server/panel/plugin/supervisor/supervisord.log",
    "/www/server/panel/plugin/supervisor/supervisor.log",
    # 系统 supervisor 常见
    "/var/log/supervisor/supervisord.log",
    "/var/log/supervisor/supervisor.log",
    "/var/log/supervisord.log",
    "/var/log/supervisord/supervisord.log",
    "/tmp/supervisord.log",
]


def _get_project_root() -> Path:
    # backend/api/supervisor_account.py -> api -> backend -> project_root
    # 期望得到：<project_root>（例如 /www/wwwroot/autosys_new）
    return Path(__file__).resolve().parents[2]


def _detect_supervisor_conf_path() -> Optional[Path]:
    p = (os.getenv("SUPERVISOR_CONF") or "").strip()
    if p:
        pp = Path(p)
        return pp if pp.exists() else pp  # 允许不存在时也返回，便于报错信息
    for cand in DEFAULT_CANDIDATE_CONFS:
        try:
            cp = Path(cand)
            if cp.exists():
                return cp
        except Exception:
            continue
    return None


def _parse_include_dir_from_conf(conf_path: Path) -> Optional[Path]:
    """
    尝试解析 supervisord.conf 的 [include] files=... 目录。
    常见格式：
      [include]
      files = /path/to/conf.d/*.ini
    """
    try:
        text = conf_path.read_text(encoding="utf-8", errors="ignore")
    except Exception:
        return None

    in_include = False
    for raw in text.splitlines():
        line = raw.strip()
        if not line or line.startswith(";") or line.startswith("#"):
            continue
        if re.match(r"^\[include\]\s*$", line, flags=re.I):
            in_include = True
            continue
        if in_include and line.startswith("[") and line.endswith("]"):
            break
        if not in_include:
            continue
        m = re.match(r"^files\s*=\s*(.+)$", line, flags=re.I)
        if not m:
            continue
        val = (m.group(1) or "").strip().strip('"').strip("'")
        if not val:
            continue
        # 只取第一个 pattern（即使写了多个用空格分隔）
        first = val.split()[0]
        p = Path(first)
        if not p.is_absolute():
            p = (conf_path.parent / p).resolve()
        return p.parent
    return None


def get_supervisor_program_dir() -> Path:
    """
    获取 supervisor program 配置目录（优先级）：
    1) SUPERVISOR_PROGRAM_DIR
    2) 从 supervisord.conf 的 [include] files= 解析
    3) 兜底：/www/server/panel/plugin/supervisor（你当前看到的目录）
    """
    env_dir = (os.getenv("SUPERVISOR_PROGRAM_DIR") or "").strip()
    if env_dir:
        return Path(env_dir)

    conf = _detect_supervisor_conf_path()
    if conf and conf.exists():
        inc = _parse_include_dir_from_conf(conf)
        if inc:
            return inc

    return Path("/www/server/panel/plugin/supervisor")


def program_name_for_account(account_id: int) -> str:
    tmpl = (os.getenv("SUPERVISOR_TRADING_PROGRAM_TEMPLATE") or "auto_sys_acc{account_id}").strip()
    try:
        return tmpl.format(account_id=int(account_id))
    except Exception:
        return f"auto_sys_acc{int(account_id)}"


def ini_filename_for_program(program_name: str) -> str:
    safe = re.sub(r"[^a-zA-Z0-9_\-:.]+", "_", program_name).strip("_") or "auto_sys"
    return f"{safe}.ini"


def render_program_ini(account_id: int, program_name: str) -> str:
    project_root = _get_project_root()
    # Python 可执行文件：
    # - 优先使用 TRADING_PYTHON_BIN（线上可显式指定 trading_system 的 venv）
    # - 否则尝试多种候选路径（避免 backend venv 未安装交易依赖导致启动失败）
    python_bin_env = (os.getenv("TRADING_PYTHON_BIN") or "").strip()
    candidates = []
    if python_bin_env:
        candidates.append(python_bin_env)
    # 当前进程 python（backend venv）
    candidates.append(sys.executable)
    # 常见 venv 位置
    candidates += [
        str(project_root / "backend" / ".venv" / "bin" / "python"),
        str(project_root / ".venv" / "bin" / "python"),
        str(project_root / "trading_system" / ".venv" / "bin" / "python"),
        "/usr/bin/python3",
        "/usr/local/bin/python3",
    ]
    python_bin = None
    for c in candidates:
        try:
            p = Path(c)
            if p.exists() and os.access(str(p), os.X_OK):
                python_bin = str(p)
                break
        except Exception:
            continue
    if not python_bin:
        # 最后兜底：写 sys.executable，让错误能在日志里体现
        python_bin = sys.executable

    # 日志目录可通过环境变量覆盖
    log_dir, out_log, err_log = expected_trading_log_paths(project_root, int(account_id))
    # supervisor 在 reread/update 时会校验 logfile 目录是否存在；这里提前创建避免 CANT_REREAD
    try:
        log_dir.mkdir(parents=True, exist_ok=True)
    except Exception:
        # 最后兜底到 /tmp，确保一定存在
        log_dir = Path("/tmp") / "autosys_logs"
        log_dir.mkdir(parents=True, exist_ok=True)
        out_log = log_dir / f"trading_{int(account_id)}.out.log"
        err_log = log_dir / f"trading_{int(account_id)}.err.log"

    # 默认不自动启动，避免“创建账号=立刻下单”
    autostart = (os.getenv("TRADING_AUTOSTART_DEFAULT", "false") or "false").lower() == "true"
    run_user = (os.getenv("SUPERVISOR_RUN_USER") or "").strip()

    return "\n".join(
        [
            f"[program:{program_name}]",
            f"directory={project_root}",
            f"command={python_bin} -m trading_system.main",
            "autostart=" + ("true" if autostart else "false"),
            # 更合理：仅在“非0退出”时重启；0 退出视为“正常结束”，不进入 FATAL 反复拉起
            "autorestart=unexpected",
            # 兼容：0/2 都视为“预期退出”（例如配置不完整/前置检查失败时主动退出）
            "exitcodes=0,2",
            "startsecs=0",
            "stopasgroup=true",
            "killasgroup=true",
            "stopsignal=TERM",
            "",
            # 关键：PYTHONPATH 指向项目根，确保 -m trading_system.main 可导入
            f'environment=ATS_ACCOUNT_ID="{int(account_id)}",PYTHONUNBUFFERED="1",PYTHONPATH="{project_root}"',
            (f"user={run_user}" if run_user else "").rstrip(),
            "",
            f"stdout_logfile={out_log}",
            f"stderr_logfile={err_log}",
            "stdout_logfile_maxbytes=20MB",
            "stdout_logfile_backups=5",
            "stderr_logfile_maxbytes=20MB",
            "stderr_logfile_backups=5",
            "",
        ]
    )


def write_program_ini(program_dir: Path, filename: str, content: str) -> Path:
    program_dir.mkdir(parents=True, exist_ok=True)
    target = program_dir / filename
    tmp = program_dir / (filename + ".tmp")
    tmp.write_text(content, encoding="utf-8")
    os.replace(str(tmp), str(target))
    return target


def _build_supervisorctl_cmd(args: list[str]) -> list[str]:
    supervisorctl_path = os.getenv("SUPERVISORCTL_PATH", "supervisorctl")
    supervisor_conf = (os.getenv("SUPERVISOR_CONF") or "").strip()
    use_sudo = (os.getenv("SUPERVISOR_USE_SUDO", "false") or "false").lower() == "true"

    if not supervisor_conf:
        conf = _detect_supervisor_conf_path()
        supervisor_conf = str(conf) if conf else ""

    cmd: list[str] = []
    if use_sudo:
        cmd += ["sudo", "-n"]
    cmd += [supervisorctl_path]
    if supervisor_conf:
        cmd += ["-c", supervisor_conf]
    cmd += args
    return cmd


def run_supervisorctl(args: list[str], timeout_sec: int = 10) -> str:
    cmd = _build_supervisorctl_cmd(args)
    try:
        res = subprocess.run(cmd, capture_output=True, text=True, timeout=int(timeout_sec))
    except subprocess.TimeoutExpired:
        raise RuntimeError("supervisorctl 超时")

    out = (res.stdout or "").strip()
    err = (res.stderr or "").strip()
    combined = "\n".join([s for s in [out, err] if s]).strip()
    # supervisorctl: status 在存在 STOPPED 等进程时可能返回 exit=3，但输出仍然有效
    ok_rc = {0}
    if args and args[0] == "status":
        ok_rc.add(3)
    if res.returncode not in ok_rc:
        raise RuntimeError(combined or f"supervisorctl failed (exit={res.returncode})")
    return combined or out


def parse_supervisor_status(raw: str) -> Tuple[bool, Optional[int], str]:
    if "RUNNING" in raw:
        m = re.search(r"\bpid\s+(\d+)\b", raw)
        pid = int(m.group(1)) if m else None
        return True, pid, "RUNNING"
    for state in ["STOPPED", "FATAL", "EXITED", "BACKOFF", "STARTING", "UNKNOWN"]:
        if state in raw:
            return False, None, state
    return False, None, "UNKNOWN"


def tail_supervisor(program: str, stream: str = "stderr", lines: int = 120) -> str:
    """
    读取 supervisor 进程最近日志（stdout/stderr）。
    supervisorctl tail -<n> <program> [stdout|stderr]
    """
    s = (stream or "stderr").strip().lower()
    if s not in {"stdout", "stderr"}:
        s = "stderr"
    n = int(lines or 120)
    if n < 20:
        n = 20
    if n > 500:
        n = 500
    return run_supervisorctl(["tail", f"-{n}", str(program), s])


def _tail_text_file(path: Path, lines: int = 200, max_bytes: int = 64 * 1024) -> str:
    """
    读取文本文件末尾（用于 supervisor spawn error 等场景，program stderr 可能为空）。
    尽量只读最后 max_bytes，避免大文件占用内存。
    """
    try:
        p = Path(path)
        if not p.exists():
            return ""
        size = p.stat().st_size
        read_size = min(int(max_bytes), int(size))
        with p.open("rb") as f:
            if size > read_size:
                f.seek(-read_size, os.SEEK_END)
            data = f.read()
        text = data.decode("utf-8", errors="ignore")
        # 仅保留最后 N 行
        parts = text.splitlines()
        if not parts:
            return ""
        n = int(lines or 200)
        if n < 20:
            n = 20
        if n > 500:
            n = 500
        return "\n".join(parts[-n:]).strip()
    except Exception:
        # 兜底：若启用 sudo（通常 backend 自己无权读 root 日志），尝试 sudo tail
        try:
            use_sudo = (os.getenv("SUPERVISOR_USE_SUDO", "false") or "false").lower() == "true"
            if not use_sudo:
                return ""
            n = int(lines or 200)
            if n < 20:
                n = 20
            if n > 500:
                n = 500
            res = subprocess.run(
                ["sudo", "-n", "tail", "-n", str(n), str(path)],
                capture_output=True,
                text=True,
                timeout=5,
            )
            out = (res.stdout or "").strip()
            err = (res.stderr or "").strip()
            # 不强行报错：宁可空，也不要影响主流程
            return (out or err or "").strip()
        except Exception:
            return ""


def _parse_supervisord_logfile_from_conf(conf_path: Path) -> Optional[Path]:
    """
    解析 supervisord.conf 中 [supervisord] 的 logfile= 路径。
    """
    try:
        text = conf_path.read_text(encoding="utf-8", errors="ignore")
    except Exception:
        return None
    in_section = False
    for raw in text.splitlines():
        line = raw.strip()
        if not line or line.startswith(";") or line.startswith("#"):
            continue
        if re.match(r"^\[supervisord\]\s*$", line, flags=re.I):
            in_section = True
            continue
        if in_section and line.startswith("[") and line.endswith("]"):
            break
        if not in_section:
            continue
        m = re.match(r"^logfile\s*=\s*(.+)$", line, flags=re.I)
        if not m:
            continue
        val = (m.group(1) or "").strip().strip('"').strip("'")
        if not val:
            continue
        p = Path(val)
        if not p.is_absolute():
            p = (conf_path.parent / p).resolve()
        return p
    return None


def tail_supervisord_log(lines: int = 200) -> str:
    """
    读取 supervisord 主日志尾部（spawn error 的根因经常在这里）。
    可通过环境变量 SUPERVISOR_LOGFILE 指定。
    """
    env_p = (os.getenv("SUPERVISOR_LOGFILE") or "").strip()
    if env_p:
        return _tail_text_file(Path(env_p), lines=lines)
    conf = _detect_supervisor_conf_path()
    if conf and conf.exists():
        lp = _parse_supervisord_logfile_from_conf(conf)
        if lp:
            return _tail_text_file(lp, lines=lines)
    # 最后兜底：尝试常见路径
    for cand in DEFAULT_SUPERVISORD_LOG_CANDIDATES:
        try:
            p = Path(cand)
            if p.exists():
                text = _tail_text_file(p, lines=lines)
                if text:
                    return text
        except Exception:
            continue
    return ""


def expected_trading_log_paths(project_root: Path, account_id: int) -> Tuple[Path, Path, Path]:
    """
    计算 trading program 的 stdout/stderr logfile 路径（需与 render_program_ini 保持一致）。
    返回 (log_dir, out_log, err_log)
    """
    log_dir = Path(os.getenv("TRADING_LOG_DIR", str(project_root / "logs"))).expanduser()
    out_log = log_dir / f"trading_{int(account_id)}.out.log"
    err_log = log_dir / f"trading_{int(account_id)}.err.log"
    return log_dir, out_log, err_log


def tail_trading_log_files(account_id: int, lines: int = 200) -> Dict[str, Any]:
    """
    直接读取该账号 trading 进程的 stdout/stderr logfile 尾部（不依赖 supervisorctl tail）。
    返回 {out_log, err_log, stdout_tail, stderr_tail}
    """
    project_root = _get_project_root()
    log_dir, out_log, err_log = expected_trading_log_paths(project_root, int(account_id))
    return {
        "log_dir": str(log_dir),
        "out_log": str(out_log),
        "err_log": str(err_log),
        "stdout_tail_file": _tail_text_file(out_log, lines=lines),
        "stderr_tail_file": _tail_text_file(err_log, lines=lines),
    }


@dataclass
class EnsureProgramResult:
    ok: bool
    program: str
    ini_path: str
    program_dir: str
    supervisor_conf: str
    reread: str = ""
    update: str = ""
    error: str = ""


def ensure_account_program(account_id: int) -> EnsureProgramResult:
    aid = int(account_id)
    program = program_name_for_account(aid)
    program_dir = get_supervisor_program_dir()
    ini_name = ini_filename_for_program(program)
    ini_text = render_program_ini(aid, program)
    conf = _detect_supervisor_conf_path()
    conf_s = str(conf) if conf else (os.getenv("SUPERVISOR_CONF") or "")

    try:
        path = write_program_ini(program_dir, ini_name, ini_text)
        reread_out = ""
        update_out = ""
        try:
            reread_out = run_supervisorctl(["reread"])
            update_out = run_supervisorctl(["update"])
        except Exception as e:
            # 写文件成功但 supervisorctl 失败也要给出可诊断信息
            return EnsureProgramResult(
                ok=False,
                program=program,
                ini_path=str(path),
                program_dir=str(program_dir),
                supervisor_conf=conf_s,
                reread=reread_out,
                update=update_out,
                error=f"写入配置成功，但执行 supervisorctl reread/update 失败: {e}",
            )

        return EnsureProgramResult(
            ok=True,
            program=program,
            ini_path=str(path),
            program_dir=str(program_dir),
            supervisor_conf=conf_s,
            reread=reread_out,
            update=update_out,
        )
    except Exception as e:
        return EnsureProgramResult(
            ok=False,
            program=program,
            ini_path="",
            program_dir=str(program_dir),
            supervisor_conf=conf_s,
            error=str(e),
        )