"use client";

import { useState } from "react";
import { signIn } from "next-auth/react";
import { useRouter } from "next/navigation";
import { useForm } from "react-hook-form";
import { zodResolver } from "@hookform/resolvers/zod";
import Link from "next/link";
import { Eye, EyeOff, TrendingUp } from "lucide-react";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
import { loginSchema, type LoginInput } from "@/lib/validations/auth";

export default function LoginPage() {
  const router = useRouter();
  const [showPassword, setShowPassword] = useState(false);
  const [error, setError] = useState<string | null>(null);

  const {
    register,
    handleSubmit,
    formState: { errors, isSubmitting },
  } = useForm<LoginInput>({ resolver: zodResolver(loginSchema) });

  async function onSubmit(data: LoginInput) {
    setError(null);
    const result = await signIn("credentials", {
      email: data.email,
      password: data.password,
      redirect: false,
    });

    if (result?.error) {
      setError("Invalid email or password");
      return;
    }

    router.push("/dashboard");
  }

  return (
    <div className="min-h-screen flex items-center justify-center bg-gradient-to-br from-slate-900 via-slate-800 to-slate-900 p-4">
      <div className="w-full max-w-md">
        <div className="flex items-center justify-center gap-2 mb-8">
          <div className="rounded-xl bg-emerald-500 p-2">
            <TrendingUp className="h-6 w-6 text-white" />
          </div>
          <span className="text-2xl font-bold text-white">FinPulse</span>
        </div>

        <Card className="border-slate-700 bg-slate-800/50 backdrop-blur">
          <CardHeader className="space-y-1">
            <CardTitle className="text-2xl text-white">Welcome back</CardTitle>
            <CardDescription className="text-slate-400">
              Sign in to your account to continue
            </CardDescription>
          </CardHeader>
          <CardContent>
            <form onSubmit={handleSubmit(onSubmit)} className="space-y-4">
              {error && (
                <div className="rounded-lg bg-red-500/10 border border-red-500/20 px-4 py-3 text-sm text-red-400">
                  {error}
                </div>
              )}

              <div className="space-y-2">
                <Label htmlFor="email" className="text-slate-300">Email</Label>
                <Input
                  id="email"
                  type="email"
                  placeholder="you@example.com"
                  className="bg-slate-700/50 border-slate-600 text-white placeholder:text-slate-500"
                  {...register("email")}
                />
                {errors.email && (
                  <p className="text-xs text-red-400">{errors.email.message}</p>
                )}
              </div>

              <div className="space-y-2">
                <Label htmlFor="password" className="text-slate-300">Password</Label>
                <div className="relative">
                  <Input
                    id="password"
                    type={showPassword ? "text" : "password"}
                    placeholder="••••••••"
                    className="bg-slate-700/50 border-slate-600 text-white placeholder:text-slate-500 pr-10"
                    {...register("password")}
                  />
                  <button
                    type="button"
                    onClick={() => setShowPassword((v) => !v)}
                    className="absolute right-3 top-1/2 -translate-y-1/2 text-slate-400 hover:text-slate-300"
                  >
                    {showPassword ? <EyeOff className="h-4 w-4" /> : <Eye className="h-4 w-4" />}
                  </button>
                </div>
                {errors.password && (
                  <p className="text-xs text-red-400">{errors.password.message}</p>
                )}
              </div>

              <Button
                type="submit"
                className="w-full bg-emerald-600 hover:bg-emerald-500 text-white"
                disabled={isSubmitting}
              >
                {isSubmitting ? "Signing in…" : "Sign in"}
              </Button>
            </form>

            <div className="mt-6 text-center text-sm text-slate-400">
              Don&apos;t have an account?{" "}
              <Link href="/register" className="text-emerald-400 hover:text-emerald-300 font-medium">
                Create one
              </Link>
            </div>
          </CardContent>
        </Card>
      </div>
    </div>
  );
}