"use client";

import { Loader2, Shield } from "lucide-react";
import { useRouter } from "next/navigation";
import { useEffect, useState } from "react";
import { login } from "@/lib/api";

export default function LoginPage() {
  const [password, setPassword] = useState("");
  const [error, setError] = useState("");
  const [loading, setLoading] = useState(false);
  const [checking, setChecking] = useState(true);
  const router = useRouter();

  useEffect(() => {
    const stored = localStorage.getItem("admin-password");
    if (stored) {
      login(stored)
        .then((ok) => {
          if (ok) router.replace("/dashboard");
          else setChecking(false);
        })
        .catch(() => setChecking(false));
    } else {
      setChecking(false);
    }
  }, [router]);

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    setError("");
    setLoading(true);

    try {
      const ok = await login(password);
      if (ok) {
        localStorage.setItem("admin-password", password);
        router.push("/dashboard");
      } else {
        setError("Invalid password");
      }
    } catch {
      setError("Connection failed. Is the backend running?");
    } finally {
      setLoading(false);
    }
  };

  if (checking) {
    return (
      <div className="flex min-h-screen items-center justify-center bg-background">
        <Loader2 className="size-6 animate-spin text-muted-foreground" />
      </div>
    );
  }

  return (
    <div className="flex min-h-screen items-center justify-center bg-background p-4">
      <div className="w-full max-w-sm space-y-6">
        <div className="flex flex-col items-center gap-2 text-center">
          <div className="flex size-12 items-center justify-center rounded-full bg-primary/10">
            <Shield className="size-6 text-primary" />
          </div>
          <h1 className="text-2xl font-semibold tracking-tight">Bete</h1>
          <p className="text-sm text-muted-foreground">
            Discord Moderation Dashboard
          </p>
        </div>

        <form onSubmit={handleSubmit} className="space-y-4">
          <div className="space-y-2">
            <label
              htmlFor="password"
              className="text-sm font-medium leading-none"
            >
              Admin Password
            </label>
            <input
              id="password"
              type="password"
              value={password}
              onChange={(e) => setPassword(e.target.value)}
              placeholder="Enter admin password"
              className="flex h-9 w-full rounded-lg border border-input bg-background px-3 py-1 text-sm shadow-sm transition-colors placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:opacity-50"
              disabled={loading}
            />
          </div>

          {error && <p className="text-sm text-destructive">{error}</p>}

          <button
            type="submit"
            disabled={loading || !password}
            className="inline-flex w-full items-center justify-center rounded-lg bg-primary px-4 py-2 text-sm font-medium text-primary-foreground shadow-sm transition-colors hover:bg-primary/90 disabled:pointer-events-none disabled:opacity-50"
          >
            {loading ? <Loader2 className="mr-2 size-4 animate-spin" /> : null}
            {loading ? "Signing in…" : "Sign in"}
          </button>
        </form>
      </div>
    </div>
  );
}