"""LocalNav 部署脚本公共工具。"""

from __future__ import annotations

import json
import os
import platform
import shutil
import socket
import subprocess
import urllib.error
import urllib.request
from pathlib import Path

DEFAULT_REPO = "https://git.bz121.com/dekun/LocalNav.git"
MIN_PYTHON = (3, 10)
APP_NAME = "nav-site"


def config_path() -> Path:
    if platform.system() == "Windows":
        base = Path(os.environ.get("USERPROFILE", Path.home())) / ".localnav"
    else:
        base = Path(os.environ.get("XDG_CONFIG_HOME", Path.home() / ".config")) / "localnav"
    base.mkdir(parents=True, exist_ok=True)
    return base / "install.json"


def load_install_config() -> dict:
    path = config_path()
    if not path.is_file():
        return {}
    try:
        return json.loads(path.read_text(encoding="utf-8"))
    except (json.JSONDecodeError, OSError):
        return {}


def save_install_config(project_dir: Path, repo: str) -> None:
    data = {
        "dir": str(project_dir.resolve()),
        "repo": repo.strip(),
    }
    config_path().write_text(json.dumps(data, indent=2) + "\n", encoding="utf-8")


def default_install_dir() -> Path:
    cfg = load_install_config()
    if cfg.get("dir"):
        return Path(cfg["dir"]).expanduser()
    if os.environ.get("NAV_INSTALL_DIR"):
        return Path(os.environ["NAV_INSTALL_DIR"]).expanduser()
    if platform.system() == "Windows":
        return Path.cwd() / "LocalNav"
    return Path("/opt/LocalNav")


def default_repo() -> str:
    cfg = load_install_config()
    return (cfg.get("repo") or os.environ.get("NAV_INSTALL_REPO") or DEFAULT_REPO).strip()


def is_localnav_project(path: Path) -> bool:
    return (path / "app.py").is_file() and (path / "scripts" / "deploy.py").is_file()


def resolve_project_dir(explicit: str | None = None) -> Path | None:
    if explicit and explicit.strip():
        p = Path(explicit.strip()).expanduser().resolve()
        return p if is_localnav_project(p) else None
    cfg_dir = load_install_config().get("dir", "").strip()
    if cfg_dir and is_localnav_project(Path(cfg_dir)):
        return Path(cfg_dir).resolve()
    here = Path.cwd()
    if is_localnav_project(here):
        return here.resolve()
    return None


def pid_file_path(project_dir: Path) -> Path:
    return project_dir / "logs" / "nav-site.pid"


def get_nav_port(project_dir: Path | None = None) -> str:
    if project_dir:
        env_file = project_dir / ".env"
        if env_file.is_file():
            for line in env_file.read_text(encoding="utf-8-sig").splitlines():
                s = line.strip()
                if s.startswith("NAV_PORT="):
                    val = s.split("=", 1)[1].strip().strip("\"'")
                    if val:
                        return val
    return os.environ.get("NAV_PORT", "5070")


def http_ready(port: str, timeout: float = 2.0) -> bool:
    url = f"http://127.0.0.1:{port}/login"
    try:
        with urllib.request.urlopen(url, timeout=timeout) as resp:
            return resp.status == 200
    except (urllib.error.URLError, TimeoutError, OSError):
        return False


def port_open(port: str) -> bool:
    try:
        p = int(port)
    except ValueError:
        return False
    try:
        with socket.create_connection(("127.0.0.1", p), timeout=1.5):
            return True
    except OSError:
        return False


def read_background_pid(project_dir: Path) -> int | None:
    path = pid_file_path(project_dir)
    if not path.is_file():
        return None
    try:
        return int(path.read_text(encoding="utf-8").strip())
    except (ValueError, OSError):
        return None


def is_process_running(pid: int) -> bool:
    if pid <= 0:
        return False
    if platform.system() == "Windows":
        try:
            proc = subprocess.run(
                ["tasklist", "/FI", f"PID eq {pid}"],
                capture_output=True,
                text=True,
                check=False,
            )
            return str(pid) in (proc.stdout or "")
        except OSError:
            return False
    try:
        os.kill(pid, 0)
        return True
    except OSError:
        return False


def stop_background_process(project_dir: Path) -> bool:
    pid = read_background_pid(project_dir)
    if not pid or not is_process_running(pid):
        pid_file_path(project_dir).unlink(missing_ok=True)
        return False
    try:
        if platform.system() == "Windows":
            subprocess.run(["taskkill", "/PID", str(pid), "/F"], check=False)
        else:
            os.kill(pid, 15)
    except OSError:
        pass
    pid_file_path(project_dir).unlink(missing_ok=True)
    return True


def pm2_available() -> str | None:
    return shutil.which("pm2")


def pm2_has_app(name: str = APP_NAME) -> bool:
    pm2 = pm2_available()
    if not pm2:
        return False
    try:
        proc = subprocess.run(
            [pm2, "jlist"],
            check=True,
            capture_output=True,
            text=True,
        )
        apps = json.loads(proc.stdout or "[]")
        return any(app.get("name") == name for app in apps)
    except (subprocess.CalledProcessError, json.JSONDecodeError, OSError):
        return False


def pm2_app_status(name: str = APP_NAME) -> str | None:
    pm2 = pm2_available()
    if not pm2:
        return None
    try:
        proc = subprocess.run(
            [pm2, "jlist"],
            check=True,
            capture_output=True,
            text=True,
        )
        for app in json.loads(proc.stdout or "[]"):
            if app.get("name") == name:
                return str(app.get("pm2_env", {}).get("status") or "unknown")
    except (subprocess.CalledProcessError, json.JSONDecodeError, OSError):
        return None
    return None


def systemd_unit_ready(name: str = APP_NAME) -> bool:
    systemctl = shutil.which("systemctl")
    if not systemctl:
        return False
    try:
        proc = subprocess.run(
            [systemctl, "list-unit-files", f"{name}.service", "--no-pager", "--no-legend"],
            check=True,
            capture_output=True,
            text=True,
        )
        return bool((proc.stdout or "").strip())
    except (subprocess.CalledProcessError, OSError):
        return False


def systemd_active(name: str = APP_NAME) -> bool:
    systemctl = shutil.which("systemctl")
    if not systemctl:
        return False
    try:
        proc = subprocess.run(
            [systemctl, "is-active", f"{name}.service"],
            check=True,
            capture_output=True,
            text=True,
        )
        return (proc.stdout or "").strip() == "active"
    except (subprocess.CalledProcessError, OSError):
        return False


def service_status_text(project_dir: Path | None) -> str:
    if not project_dir:
        return "未安装"

    port = get_nav_port(project_dir)
    if http_ready(port):
        pm2_state = pm2_app_status()
        if pm2_state:
            return f"运行中 · pm2 {pm2_state} · :{port}"
        if systemd_unit_ready() and systemd_active():
            return f"运行中 · systemd · :{port}"
        pid = read_background_pid(project_dir)
        if pid and is_process_running(pid):
            return f"运行中 · 后台 pid {pid} · :{port}"
        return f"运行中 · 端口 {port}"

    pm2_state = pm2_app_status()
    if pm2_state:
        return f"pm2 {pm2_state}（未响应 :{port}）"
    if systemd_unit_ready() and systemd_active():
        return f"systemd active（未响应 :{port}）"
    if systemd_unit_ready():
        return "systemd 已配置但未运行"
    pid = read_background_pid(project_dir)
    if pid and is_process_running(pid):
        return f"后台 pid {pid}（未响应 :{port}）"
    if port_open(port):
        return f"端口 {port} 已占用（进程未知）"
    return "未运行"


def stop_service(project_dir: Path | None = None) -> list[str]:
    """停止并移除进程管理中的 nav-site，返回已执行操作说明。"""
    actions: list[str] = []
    pm2 = pm2_available()
    if pm2 and pm2_has_app():
        subprocess.run([pm2, "stop", APP_NAME], check=False)
        subprocess.run([pm2, "delete", APP_NAME], check=False)
        subprocess.run([pm2, "save"], check=False)
        actions.append("pm2 stop/delete nav-site")

    systemctl = shutil.which("systemctl")
    if systemctl and systemd_unit_ready():
        subprocess.run([systemctl, "stop", f"{APP_NAME}.service"], check=False)
        subprocess.run([systemctl, "disable", f"{APP_NAME}.service"], check=False)
        actions.append("systemctl stop/disable nav-site")

    if project_dir and stop_background_process(project_dir):
        actions.append("已停止后台 nav-site 进程")

    return actions