import asyncio
import subprocess
import re
import os
import shutil
import logging
import time
import threading
from typing import Optional
from fastapi import APIRouter
from fastapi.responses import JSONResponse

logger = logging.getLogger(__name__)
router = APIRouter()

_sshx_link = None
_sshx_pid = None
_sshx_log = "/tmp/sshx_link.log"

LINK_RE = re.compile(r"https://sshx\.io/s/[A-Za-z0-9_-]+")


def _ensure_sshx() -> bool:
    if shutil.which("sshx"):
        return True
    try:
        subprocess.run(
            ["sh", "-c", "curl -sSf https://sshx.io/get | sh"],
            capture_output=True, timeout=60,
        )
        return shutil.which("sshx") is not None
    except Exception as e:
        logger.error("sshx install failed: %s", e)
        return False


def _kill_sshx():
    global _sshx_pid, _sshx_link
    if _sshx_pid:
        try:
            os.kill(_sshx_pid, 15)
        except ProcessLookupError:
            pass
        _sshx_pid = None
    _sshx_link = None
    if os.path.exists(_sshx_log):
        os.remove(_sshx_log)


def _is_alive() -> bool:
    global _sshx_pid
    if not _sshx_pid:
        return False
    try:
        os.kill(_sshx_pid, 0)
        return True
    except ProcessLookupError:
        return False


def _start_sshx_background():
    global _sshx_pid, _sshx_link
    _kill_sshx()
    _sshx_link = None

    subprocess.Popen(
        ["nohup", "sshx", "--quiet"],
        stdout=open(_sshx_log, "w"),
        stderr=subprocess.DEVNULL,
        stdin=subprocess.DEVNULL,
        start_new_session=True,
    )

    for _ in range(30):
        time.sleep(1)
        if os.path.exists(_sshx_log) and os.path.getsize(_sshx_log) > 0:
            with open(_sshx_log) as f:
                content = f.read().strip()
            m = LINK_RE.search(content)
            if m:
                _sshx_link = m.group(0)
                try:
                    with open("/tmp/sshx_pid") as pf:
                        _sshx_pid = int(pf.read().strip())
                except Exception:
                    pass
                return True
    return False


@router.get("/start")
async def start_sshx():
    global _sshx_link, _sshx_pid

    if _is_alive() and _sshx_link:
        return {"status": "running", "link": _sshx_link}

    if not _ensure_sshx():
        return JSONResponse(status_code=500, content={"status": "error", "message": "Failed to install sshx"})

    loop = asyncio.get_event_loop()
    result = await loop.run_in_executor(None, _start_sshx_background)

    if result:
        return {"status": "running", "link": _sshx_link}
    return JSONResponse(status_code=504, content={"status": "error", "message": "sshx did not return a link in time"})


@router.get("/status")
async def sshx_status():
    global _sshx_link
    if _is_alive() and _sshx_link:
        return {"status": "running", "link": _sshx_link}
    return {"status": "stopped", "link": None}


@router.post("/stop")
async def stop_sshx():
    _kill_sshx()
    return {"status": "stopped"}


@router.post("/restart-dashboard")
async def restart_dashboard():
    try:
        subprocess.Popen(
            ["nohup", "bash", "-c", "sleep 1 && sudo systemctl restart hermes-dashboard"],
            stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL,
            start_new_session=True,
        )
        return {"status": "restarting"}
    except Exception as e:
        return JSONResponse(status_code=500, content={"status": "error", "message": str(e)})