'use client';

import { Suspense, useEffect, useState } from 'react';
import Link from 'next/link';
import { useRouter, useSearchParams } from 'next/navigation';
import { Lock, Eye, EyeOff, ArrowRight, CheckCircle2, Shield } from 'lucide-react';
import { Card, CardHeader, CardTitle, CardDescription, CardContent, CardFooter } from '@/components/ui/card';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { authService } from '@/services/auth.service';
import { getErrorMessage } from '@/lib/errors';
import { useSystemConfig } from '@/hooks/useSystemConfig';

export default function ResetPasswordPage() {
  return (
    <Suspense fallback={<div className="min-h-screen" />}>
      <ResetInner />
    </Suspense>
  );
}

function ResetInner() {
  const router = useRouter();
  const sysConfig = useSystemConfig();
  const searchParams = useSearchParams();
  const [token, setToken] = useState('');
  const [password, setPassword] = useState('');
  const [confirm, setConfirm] = useState('');
  const [showPassword, setShowPassword] = useState(false);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [done, setDone] = useState(false);

  useEffect(() => {
    const t = searchParams.get('token');
    if (t) setToken(t);
  }, [searchParams]);

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    setError(null);
    if (password !== confirm) {
      setError('Passwords do not match.');
      return;
    }
    if (password.length < sysConfig.minPasswordLength) {
      setError(`Password must be at least ${sysConfig.minPasswordLength} characters long.`);
      return;
    }
    setLoading(true);
    try {
      await authService.resetPassword({ token, newPassword: password });
      setDone(true);
      setTimeout(() => router.replace('/login'), 2000);
    } catch (err) {
      setError(getErrorMessage(err));
      setLoading(false);
    }
  };

  return (
    <div className="relative flex min-h-screen items-center justify-center overflow-hidden bg-surface-sunken px-4 py-10">
      <div className="pointer-events-none absolute inset-0">
        <div className="absolute -left-40 -top-40 h-96 w-96 rounded-full bg-primary-500/20 blur-3xl" />
        <div className="absolute -bottom-40 -right-40 h-96 w-96 rounded-full bg-indigo-500/20 blur-3xl" />
        <div className="absolute inset-0 bg-grid opacity-40" />
      </div>

      <div className="relative mx-auto w-full max-w-md">
        <div className="mb-6 text-center">
          <Link href="/" className="inline-flex items-center gap-2 mb-4">
            <div className="flex h-10 w-10 items-center justify-center rounded-xl bg-gradient-to-br from-primary-500 to-indigo-600 text-white">
              <Shield className="h-5 w-5" />
            </div>
            <span className="text-xl font-bold text-ink">{sysConfig.projectName}</span>
          </Link>
        </div>

        <Card className="card-hover">
          <CardHeader>
            <CardTitle className="text-2xl">Set a new password</CardTitle>
            <CardDescription className="mt-2">Choose a strong, unique password for your account.</CardDescription>
          </CardHeader>

          {error && (
            <div className="mx-5 mb-3 flex items-start gap-2 rounded-xl border border-red-500/30 bg-red-500/10 p-3 text-sm text-red-600 dark:text-red-300">
              <span>{error}</span>
            </div>
          )}

          {done ? (
            <CardContent>
              <div className="flex items-start gap-3 rounded-xl border border-emerald-500/30 bg-emerald-500/10 p-4 text-sm text-emerald-600 dark:text-emerald-300">
                <CheckCircle2 className="mt-0.5 h-5 w-5 shrink-0" />
                <div>
                  <p className="font-medium">Password updated</p>
                  <p className="mt-1 text-emerald-600/80 dark:text-emerald-300/80">
                    Redirecting you to sign in...
                  </p>
                </div>
              </div>
            </CardContent>
          ) : (
            <form onSubmit={handleSubmit}>
              <CardContent className="space-y-4">
                <div>
                  <label htmlFor="password" className="mb-1.5 block text-sm font-medium text-ink">New Password</label>
                  <div className="relative">
                    <Input
                      id="password"
                      type={showPassword ? 'text' : 'password'}
                      placeholder={`Min. ${sysConfig.minPasswordLength} characters`}
                      icon={<Lock className="h-4 w-4" />}
                      value={password}
                      onChange={(e) => setPassword(e.target.value)}
                      required
                      autoComplete="new-password"
                      className="pr-10"
                    />
                    <button
                      type="button"
                      onClick={() => setShowPassword((v) => !v)}
                      className="absolute right-3 top-1/2 -translate-y-1/2 text-ink-faint hover:text-ink"
                      aria-label={showPassword ? 'Hide password' : 'Show password'}
                    >
                      {showPassword ? <EyeOff className="h-4 w-4" /> : <Eye className="h-4 w-4" />}
                    </button>
                  </div>
                </div>
                <div>
                  <label htmlFor="confirm" className="mb-1.5 block text-sm font-medium text-ink">Confirm Password</label>
                  <div className="relative">
                    <Input
                      id="confirm"
                      type={showPassword ? 'text' : 'password'}
                      placeholder="Repeat your password"
                      icon={<Lock className="h-4 w-4" />}
                      value={confirm}
                      onChange={(e) => setConfirm(e.target.value)}
                      required
                      autoComplete="new-password"
                      className="pr-10"
                    />
                  </div>
                  {confirm && password !== confirm && (
                    <p className="mt-1.5 text-xs text-red-500">Passwords do not match.</p>
                  )}
                </div>
                <Button type="submit" className="w-full" loading={loading}>
                  {loading ? 'Updating...' : 'Update Password'}
                  {!loading && <ArrowRight className="h-4 w-4" />}
                </Button>
              </CardContent>
            </form>
          )}

          <CardFooter className="justify-center">
            <p className="text-sm text-ink-muted">
              <Link href="/login" className="font-semibold text-primary-600 hover:underline">Back to sign in</Link>
            </p>
          </CardFooter>
        </Card>
      </div>
    </div>
  );
}