import { useEffect, useState } from "react";
import { useTheme } from "next-themes";
import { Sun, Moon, Monitor } from "lucide-react";
import { Button } from "@/components/ui/button";
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu";

interface ThemeToggleProps {
  className?: string;
}

const themeLabels: Record<string, string> = {
  light: "Hell",
  dark: "Dunkel",
  system: "System",
};

export function ThemeToggle({ className }: ThemeToggleProps) {
  const { theme, setTheme, resolvedTheme } = useTheme();
  const [mounted, setMounted] = useState(false);

  useEffect(() => {
    setMounted(true);
  }, []);

  const currentLabel = themeLabels[theme ?? "system"] ?? "System";

  const icon = !mounted ? (
    <Monitor className="h-4 w-4" />
  ) : theme === "system" ? (
    <Monitor className="h-4 w-4" />
  ) : resolvedTheme === "dark" ? (
    <Moon className="h-4 w-4" />
  ) : (
    <Sun className="h-4 w-4" />
  );

  return (
    <DropdownMenu>
      <DropdownMenuTrigger asChild>
        <Button
          variant="ghost"
          size="icon"
          className={className}
          aria-label={`Theme wechseln, aktuell: ${currentLabel}`}
        >
          {icon}
          <span className="sr-only">Theme wechseln</span>
        </Button>
      </DropdownMenuTrigger>
      <DropdownMenuContent align="end">
        <DropdownMenuItem onClick={() => setTheme("light")}>
          <Sun className="mr-2 h-4 w-4" />
          Hell
        </DropdownMenuItem>
        <DropdownMenuItem onClick={() => setTheme("dark")}>
          <Moon className="mr-2 h-4 w-4" />
          Dunkel
        </DropdownMenuItem>
        <DropdownMenuItem onClick={() => setTheme("system")}>
          <Monitor className="mr-2 h-4 w-4" />
          System
        </DropdownMenuItem>
      </DropdownMenuContent>
    </DropdownMenu>
  );
}