import json
from typing import Any

from services.runner import run_cmd


def _format_uptime(seconds: int | float | None) -> str:
    if seconds is None:
        return "unknown"
    total = int(seconds)
    days, rem = divmod(total, 86400)
    hours, rem = divmod(rem, 3600)
    minutes, _ = divmod(rem, 60)
    if days > 0:
        return f"{days}d {hours:02d}:{minutes:02d}"
    return f"{hours:02d}:{minutes:02d}"


def _format_load(load: list[Any] | None) -> str:
    if not load or not isinstance(load, list):
        return "unknown"
    values = []
    for raw in load[:3]:
        try:
            values.append(float(raw) / 65536.0)
        except (TypeError, ValueError):
            values.append(0.0)
    return " ".join(f"{val:.2f}" for val in values)


def _format_rate(rate: Any) -> str:
    try:
        val = float(rate)
    except (TypeError, ValueError):
        return "?"
    if val <= 0:
        return "?"
    return f"{val / 1000:.1f}M"


def _extract_wan_ip(wan: dict[str, Any]) -> str | None:
    if not isinstance(wan, dict):
        return None
    addrs = wan.get("ipv4-address") or []
    if isinstance(addrs, list):
        for item in addrs:
            if isinstance(item, dict):
                ip = item.get("address")
                if ip:
                    return str(ip)
    return None


def _extract_wifi_clients(wireless: dict[str, Any]) -> list[str]:
    clients: list[str] = []
    if not isinstance(wireless, dict):
        return clients
    for radio in wireless.values():
        if not isinstance(radio, dict):
            continue
        for iface in radio.get("interfaces", []) or []:
            if not isinstance(iface, dict):
                continue
            ifname = iface.get("ifname") or "wifi"
            assoclist = iface.get("assoclist") or {}
            if not isinstance(assoclist, dict):
                continue
            for mac, meta in assoclist.items():
                if not isinstance(meta, dict):
                    continue
                signal = meta.get("signal")
                rx = _format_rate((meta.get("rx") or {}).get("rate"))
                tx = _format_rate((meta.get("tx") or {}).get("rate"))
                sig = f"{signal}dBm" if isinstance(signal, (int, float)) else "?"
                clients.append(f"{ifname} {mac} {sig} rx:{rx} tx:{tx}")
    return clients


def _extract_leases(leases: dict[str, Any]) -> list[str]:
    items = leases.get("leases") if isinstance(leases, dict) else None
    if not isinstance(items, list):
        return []
    out = []
    for lease in items:
        if not isinstance(lease, dict):
            continue
        ipaddr = lease.get("ipaddr") or "?"
        host = lease.get("hostname") or "unknown"
        mac = lease.get("macaddr") or "?"
        out.append(f"{ipaddr} {host} ({mac})")
    return out


async def get_openwrt_status(cfg: dict[str, Any]) -> str:
    ow_cfg = cfg.get("openwrt", {})
    host = ow_cfg.get("host")
    user = ow_cfg.get("user", "root")
    port = ow_cfg.get("port", 22)
    identity_file = ow_cfg.get("identity_file")
    timeout_sec = ow_cfg.get("timeout_sec", 8)
    strict = ow_cfg.get("strict_host_key_checking", True)

    if not host:
        return "⚠️ OpenWrt host not configured"

    ssh_cmd = [
        "ssh",
        "-o",
        "BatchMode=yes",
        "-o",
        f"ConnectTimeout={timeout_sec}",
    ]
    if not strict:
        ssh_cmd += ["-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null"]
    if identity_file:
        ssh_cmd += ["-i", str(identity_file)]
    ssh_cmd += ["-p", str(port), f"{user}@{host}"]

    remote = (
        "ubus call system info; echo __SEP__;"
        "ubus call network.interface.wan status; echo __SEP__;"
        "ubus call network.wireless status; echo __SEP__;"
        "ubus call dhcp ipv4leases"
    )
    cmd = ssh_cmd + ["sh", "-c", remote]
    rc, out = await run_cmd(cmd, timeout=timeout_sec + 5)
    if rc != 0:
        return f"⚠️ OpenWrt SSH error: {out.strip() or 'unknown error'}"

    parts = [p.strip() for p in out.split("__SEP__")]
    if len(parts) < 4:
        return "⚠️ OpenWrt response incomplete"

    try:
        sys_info = json.loads(parts[0])
        wan_status = json.loads(parts[1])
        wireless = json.loads(parts[2])
        leases = json.loads(parts[3])
    except json.JSONDecodeError:
        return "⚠️ OpenWrt response parse error"

    uptime = _format_uptime(sys_info.get("uptime") if isinstance(sys_info, dict) else None)
    load = _format_load(sys_info.get("load") if isinstance(sys_info, dict) else None)
    wan_ip = _extract_wan_ip(wan_status) or "unknown"
    wan_up = wan_status.get("up") if isinstance(wan_status, dict) else None
    wan_state = "up" if wan_up else "down"

    wifi_clients = _extract_wifi_clients(wireless)
    leases_list = _extract_leases(leases)

    lines = [
        "📡 OpenWrt",
        f"🕒 Uptime: {uptime}",
        f"⚙️ Load: {load}",
        f"🌐 WAN: {wan_ip} ({wan_state})",
        "",
        f"📶 Wi-Fi clients: {len(wifi_clients)}",
    ]
    if wifi_clients:
        for line in wifi_clients[:20]:
            lines.append(f"  - {line}")
        if len(wifi_clients) > 20:
            lines.append(f"  … and {len(wifi_clients) - 20} more")
    else:
        lines.append("  (none)")

    lines += ["", f"🧾 DHCP leases: {len(leases_list)}"]
    if leases_list:
        for line in leases_list[:20]:
            lines.append(f"  - {line}")
        if len(leases_list) > 20:
            lines.append(f"  … and {len(leases_list) - 20} more")
    else:
        lines.append("  (none)")

    return "\n".join(lines)