import {
  Cpu,
  Wifi,
  WifiOff,
  Loader,
  Terminal,
  ChevronDown,
  LogOut,
  User,
} from "lucide-react";
import type { GpuInfo, MonitoringSample } from "../../types.js";
import { fmt } from "../../utils/units.js";
import { useCurveStore } from "../../store/curveStore.js";
import { useState, useRef, useEffect } from "react";

interface Props {
  gpuInfo: GpuInfo | null;
  wsStatus: "connecting" | "connected" | "disconnected";
  monitor: MonitoringSample | null;
  user?: string | null;
  onLogout?: () => void;
}

const statusIcon = {
  connected: <Wifi size={14} className="text-emerald-400" />,
  connecting: <Loader size={14} className="text-yellow-400 animate-spin" />,
  disconnected: <WifiOff size={14} className="text-red-400" />,
};

const statusText = {
  connected: "Connected",
  connecting: "Connecting…",
  disconnected: "Disconnected",
};

export function StatusBar({
  gpuInfo,
  wsStatus,
  monitor,
  user,
  onLogout,
}: Props) {
  const { availableGpus, selectedGpuIndex, setSelectedGpuIndex } =
    useCurveStore();
  const [isOpen, setIsOpen] = useState(false);
  const dropdownRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    function handleClickOutside(event: MouseEvent) {
      if (
        dropdownRef.current &&
        !dropdownRef.current.contains(event.target as Node)
      ) {
        setIsOpen(false);
      }
    }
    document.addEventListener("mousedown", handleClickOutside);
    return () => document.removeEventListener("mousedown", handleClickOutside);
  }, []);

  return (
    <header className="bg-zinc-900 border-b border-zinc-800 text-sm">
      <div className="flex items-center gap-4 px-4 py-2 w-full max-w-[1600px] mx-auto min-w-0">
        {/* Left: GPU name */}
        <div className="flex items-center gap-2 min-w-0 shrink-0">
          <img src="/logo.svg" alt="NVCurve" className="w-5 h-5 shrink-0" />
          <span className="font-bold text-transparent bg-clip-text bg-gradient-to-r from-violet-400 to-fuchsia-400 tracking-tight mr-1">
            NVCurve
          </span>
          <div className="w-px h-4 bg-zinc-700 mx-1 hidden sm:block"></div>

          {availableGpus.length > 1 ? (
            <div className="relative" ref={dropdownRef}>
              <button
                onClick={() => setIsOpen(!isOpen)}
                className="flex items-center gap-1.5 px-2 py-1 -ml-2 rounded hover:bg-zinc-800 transition-colors group"
              >
                <Cpu
                  size={14}
                  className="text-zinc-400 group-hover:text-zinc-300 transition-colors"
                />
                <span className="font-medium text-zinc-200 truncate group-hover:text-white transition-colors">
                  {gpuInfo?.name ?? "No Device"}
                </span>
                <ChevronDown
                  size={14}
                  className={`text-zinc-500 transition-transform ${isOpen ? "rotate-180" : ""}`}
                />
              </button>

              {isOpen && (
                <div className="absolute top-full left-0 mt-1 w-64 bg-zinc-800 border border-zinc-700 rounded-lg shadow-xl overflow-hidden z-50 py-1">
                  {availableGpus.map((gpu) => (
                    <button
                      key={gpu.index}
                      onClick={() => {
                        setSelectedGpuIndex(gpu.index);
                        setIsOpen(false);
                      }}
                      className={`w-full text-left px-3 py-2 text-sm flex items-center gap-2 hover:bg-zinc-700 transition-colors ${
                        gpu.index === selectedGpuIndex
                          ? "text-cyan-400 font-medium bg-zinc-700/50"
                          : "text-zinc-300"
                      }`}
                    >
                      <Cpu
                        size={14}
                        className={
                          gpu.index === selectedGpuIndex
                            ? "text-cyan-400"
                            : "text-zinc-500"
                        }
                      />
                      <span className="truncate flex-1">{gpu.name}</span>
                      <span className="text-xs text-zinc-500 font-mono">
                        GPU {gpu.index}
                      </span>
                    </button>
                  ))}
                </div>
              )}
            </div>
          ) : (
            <>
              <Cpu
                size={16}
                className="shrink-0 text-zinc-400 ml-1 hidden sm:block"
              />
              <span className="font-medium text-zinc-200 truncate">
                {gpuInfo?.name ?? "No Device"}
              </span>
            </>
          )}

          {gpuInfo?.driver_version && (
            <div className="flex items-center gap-1.5 text-zinc-400 shrink-0 hidden sm:flex bg-zinc-800/80 border border-zinc-700/50 px-2 py-0.5 rounded text-xs ml-2">
              <Terminal size={12} className="text-zinc-500" />
              <span>{gpuInfo.driver_version}</span>
            </div>
          )}
        </div>

        {/* Centre: live stats */}
        <div className="flex-1 flex items-center justify-center gap-5 min-w-0 hidden lg:flex">
          <StatPill
            label="Temp"
            value={fmt.celsius(monitor?.temp_c)}
            color="text-orange-400"
          />
          <StatPill
            label="Power"
            value={fmt.watts(monitor?.power_w)}
            color="text-pink-400"
          />
          <StatPill
            label="Fan"
            value={fmt.pct(monitor?.fan_pct)}
            color="text-blue-400"
          />
          <StatPill
            label="GPU Util"
            value={fmt.pct(monitor?.gpu_util_pct)}
            color="text-yellow-400"
          />
          <StatPill
            label="Mem Util"
            value={fmt.pct(monitor?.mem_util_pct)}
            color="text-sky-400"
          />
        </div>

        {/* Right: user + connection status */}
        <div className="flex items-center gap-3 shrink-0">
          {user && (
            <div className="flex items-center gap-1.5 text-zinc-400">
              <User size={14} className="text-zinc-500" />
              <span className="hidden sm:inline text-zinc-300">{user}</span>
              {onLogout && (
                <button
                  onClick={onLogout}
                  title="Sign out"
                  className="p-1 rounded hover:bg-zinc-800 hover:text-zinc-200 transition-colors"
                >
                  <LogOut size={14} />
                </button>
              )}
            </div>
          )}
          <div className="flex items-center gap-1.5 text-zinc-400">
            {statusIcon[wsStatus]}
            <span className="hidden sm:inline">{statusText[wsStatus]}</span>
          </div>
        </div>
      </div>
    </header>
  );
}

function StatPill({
  label,
  value,
  color,
}: {
  label: string;
  value: string;
  color: string;
}) {
  return (
    <div className="flex items-baseline gap-1">
      <span className="text-zinc-500 text-xs">{label}</span>
      <span className={`font-mono font-semibold text-sm ${color}`}>
        {value}
      </span>
    </div>
  );
}