"use client";

import { Suspense, useState } from "react";
import { signIn } from "next-auth/react";
import { useRouter, useSearchParams } from "next/navigation";
import Link from "next/link";
import { Code2, CheckCircle, Loader2 } from "lucide-react";
import { cn } from "@/lib/utils";

export default function LoginPage() {
  return (
    <Suspense>
      <LoginForm />
    </Suspense>
  );
}

function LoginForm() {
  const router = useRouter();
  const searchParams = useSearchParams();
  const verified = searchParams.get("verified") === "true";
  const [email, setEmail] = useState("");
  const [password, setPassword] = useState("");
  const [error, setError] = useState("");
  const [loading, setLoading] = useState(false);

  const emailValid = /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
  const passwordValid = password.length >= 8;

  async function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    setError("");
    if (!emailValid) { setError("Please enter a valid email address"); return; }
    if (!passwordValid) { setError("Password must be at least 8 characters"); return; }
    setLoading(true);
    const result = await signIn("credentials", { email, password, redirect: false });
    if (result?.error) { setError("Invalid email or password"); setLoading(false); return; }
    router.push("/dashboard");
    router.refresh();
  }

  return (
    <div className="space-y-8">
      <div className="flex flex-col items-center gap-4">
        <div className="w-12 h-12 rounded-xl bg-gradient-to-br from-blue-400 to-blue-600 flex items-center justify-center shadow-lg shadow-blue-500/20">
          <Code2 className="w-6 h-6 text-white" />
        </div>
        <div className="text-center">
          <h1 className="text-2xl font-bold text-neutral-100">Welcome back</h1>
          <p className="mt-1 text-sm text-neutral-400">Sign in to your CodeBoard account</p>
        </div>
      </div>

      {verified && (
        <div className="rounded-lg bg-blue-500/10 border border-blue-500/20 px-4 py-3 flex items-center gap-2">
          <CheckCircle className="w-4 h-4 text-blue-400 shrink-0" />
          <p className="text-sm text-blue-400">Email verified! You can now sign in.</p>
        </div>
      )}

      <form onSubmit={handleSubmit} className="space-y-5">
        <div className="rounded-xl bg-neutral-900 border border-neutral-800 p-6 space-y-4">
          <div className="space-y-2">
            <label htmlFor="email" className="block text-sm font-medium text-neutral-300">Email</label>
            <input id="email" type="email" autoComplete="email" required value={email} onChange={(e) => setEmail(e.target.value)} placeholder="you@example.com"
              className={cn("w-full px-3 py-2.5 bg-neutral-950 border rounded-lg text-sm text-neutral-100 placeholder-neutral-500 outline-none transition-colors", email && !emailValid ? "border-red-500/50 focus:border-red-500" : "border-neutral-800 focus:border-blue-500")} />
            {email && !emailValid && <p className="text-xs text-red-400">Please enter a valid email address</p>}
          </div>
          <div className="space-y-2">
            <label htmlFor="password" className="block text-sm font-medium text-neutral-300">Password</label>
            <input id="password" type="password" autoComplete="current-password" required value={password} onChange={(e) => setPassword(e.target.value)} placeholder="••••••••"
              className={cn("w-full px-3 py-2.5 bg-neutral-950 border rounded-lg text-sm text-neutral-100 placeholder-neutral-500 outline-none transition-colors", password && !passwordValid ? "border-red-500/50 focus:border-red-500" : "border-neutral-800 focus:border-blue-500")} />
            {password && !passwordValid && <p className="text-xs text-red-400">Password must be at least 8 characters</p>}
          </div>
        </div>
        <div className="flex justify-end">
          <Link href="/forgot-password" className="text-sm text-neutral-500 hover:text-blue-400 transition-colors">Forgot password?</Link>
        </div>
        {error && (<div className="rounded-lg bg-red-500/10 border border-red-500/20 px-4 py-3"><p className="text-sm text-red-400">{error}</p></div>)}
        <button type="submit" disabled={loading}
          className={cn("w-full flex items-center justify-center gap-2 px-4 py-2.5 rounded-lg text-sm font-semibold transition-colors", loading ? "bg-blue-500/50 text-white/50 cursor-not-allowed" : "bg-blue-500 hover:bg-blue-400 text-white")}>
          {loading && <Loader2 className="w-4 h-4 animate-spin" />}
          {loading ? "Signing in…" : "Sign in"}
        </button>
      </form>
      <p className="text-center text-sm text-neutral-400">Don&apos;t have an account?{" "}<Link href="/register" className="text-blue-400 hover:text-blue-300 font-medium transition-colors">Create one</Link></p>
    </div>
  );
}