"use client";

import { useState } from "react";
import { useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";
import { z } from "zod";
import { Loader2, ShieldCheck } from "lucide-react";
import { toast } from "sonner";
import { useRouter } from "next/navigation";
import { authClient } from "@/lib/auth-client";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import {
  Form,
  FormControl,
  FormField,
  FormItem,
  FormLabel,
  FormMessage,
} from "@/components/ui/form";
import { Checkbox } from "@/components/ui/checkbox";

const formSchema = z.object({
  code: z.string().length(6, "Code must be 6 digits").regex(/^\d+$/, "Code must be numeric"),
  trustDevice: z.boolean(),
});

type FormData = z.infer<typeof formSchema>;

interface TwoFactorFormProps {
  callbackURL?: string;
}

export function TwoFactorForm({ callbackURL = "/" }: TwoFactorFormProps) {
  const [isLoading, setIsLoading] = useState(false);
  const router = useRouter();

  const form = useForm<FormData>({
    resolver: zodResolver(formSchema),
    defaultValues: {
      code: "",
      trustDevice: true,
    },
  });

  async function onSubmit(data: FormData) {
    setIsLoading(true);
    try {
      const result = await authClient.twoFactor.verifyTotp({
        code: data.code,
        trustDevice: data.trustDevice,
      });

      if (result.error) {
        toast.error(result.error.message || "Invalid verification code");
        form.setError("code", { message: "Invalid code" });
        return;
      }

      toast.success("Verified successfully!");
      router.push(callbackURL);
    } catch (error) {
      toast.error("An unexpected error occurred");
      console.error("2FA verification error:", error);
    } finally {
      setIsLoading(false);
    }
  }

  return (
    <Form {...form}>
      <form onSubmit={form.handleSubmit(onSubmit)} className="space-y-6">
        <FormField
          control={form.control}
          name="code"
          render={({ field }) => (
            <FormItem>
              <FormLabel>Verification Code</FormLabel>
              <FormControl>
                <Input
                  placeholder="000000"
                  maxLength={6}
                  className="text-center text-2xl tracking-widest font-mono"
                  {...field}
                  disabled={isLoading}
                  autoComplete="one-time-code"
                  inputMode="numeric"
                />
              </FormControl>
              <FormMessage />
            </FormItem>
          )}
        />

        <FormField
          control={form.control}
          name="trustDevice"
          render={({ field }) => (
            <FormItem className="flex flex-row items-start space-x-3 space-y-0">
              <FormControl>
                <Checkbox
                  checked={field.value}
                  onCheckedChange={field.onChange}
                  disabled={isLoading}
                />
              </FormControl>
              <div className="space-y-1 leading-none">
                <FormLabel className="text-sm font-normal">
                  Trust this device for 30 days
                </FormLabel>
              </div>
            </FormItem>
          )}
        />

        <Button type="submit" className="w-full" disabled={isLoading}>
          {isLoading ? (
            <>
              <Loader2 className="mr-2 h-4 w-4 animate-spin" />
              Verifying...
            </>
          ) : (
            <>
              <ShieldCheck className="mr-2 h-4 w-4" />
              Verify
            </>
          )}
        </Button>
      </form>
    </Form>
  );
}