'use client';

import { useState } from 'react';
import { useTranslations } from 'next-intl';
import { motion } from 'framer-motion';
import { MapPin, Phone, Mail, Send, Loader2, CheckCircle2, AlertTriangle } from 'lucide-react';
import Image from 'next/image';

interface FormData {
  name: string;
  email: string;
  message: string;
}

export function ContactForm() {
  const t = useTranslations('pages.contact');

  const MAX_MESSAGE_LENGTH = 1000;

  const [isSubmitting, setIsSubmitting] = useState(false);
  const [submitStatus, setSubmitStatus] = useState<'idle' | 'success' | 'error'>('idle');
  const [errorMessage, setErrorMessage] = useState<string>('');
  const [formData, setFormData] = useState<FormData>({
    name: '',
    email: '',
    message: ''
  });
  const [errors, setErrors] = useState<Partial<FormData>>({});
  const [remainingAttempts, setRemainingAttempts] = useState<number | null>(null);

  const messageLength = formData.message.length;

  const validateForm = () => {
    const newErrors: Partial<FormData> = {};

    if (!formData.name.trim()) {
      newErrors.name = t('contactForm.errors.nameRequired');
    }

    if (!formData.email.trim()) {
      newErrors.email = t('contactForm.errors.emailRequired');
    } else if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(formData.email)) {
      newErrors.email = t('contactForm.errors.emailInvalid');
    }

    if (!formData.message.trim()) {
      newErrors.message = t('contactForm.errors.messageRequired');
    }

    setErrors(newErrors);
    return Object.keys(newErrors).length === 0;
  };

  const handleChange = (
    e: React.ChangeEvent<HTMLInputElement | HTMLTextAreaElement>
  ) => {
    const { name, value } = e.target;
    setFormData(prev => ({ ...prev, [name]: value }));
    if (errors[name as keyof FormData]) {
      setErrors(prev => ({ ...prev, [name]: undefined }));
    }
  };

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();

    if (!validateForm()) return;

    setIsSubmitting(true);
    setSubmitStatus('idle');
    setErrorMessage('');

    try {
      const response = await fetch('/api/contact', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify(formData),
      });

      const data = await response.json();

      // Parse rate limit headers
      const rateLimitRemaining = response.headers.get('X-RateLimit-Remaining');
      if (rateLimitRemaining !== null) {
        setRemainingAttempts(parseInt(rateLimitRemaining, 10));
      }

      if (response.ok) {
        setSubmitStatus('success');
        setFormData({ name: '', email: '', message: '' });
      } else if (response.status === 429) {
        // Rate limit exceeded
        setSubmitStatus('error');
        setRemainingAttempts(0);
        const retryAfter = data.retryAfter || 0;
        const minutes = Math.ceil(retryAfter / 60);
        const hours = Math.floor(minutes / 60);
        const remainingMinutes = minutes % 60;

        let timeMessage = '';
        if (hours > 0) {
          timeMessage = `${hours} hour${hours > 1 ? 's' : ''}${remainingMinutes > 0 ? ` and ${remainingMinutes} minute${remainingMinutes > 1 ? 's' : ''}` : ''}`;
        } else {
          timeMessage = `${minutes} minute${minutes > 1 ? 's' : ''}`;
        }

        setErrorMessage(
          t('contactForm.rateLimit.error', { time: timeMessage })
        );
      } else {
        // Other errors (400, 500, etc.)
        setSubmitStatus('error');
        setErrorMessage(data.error || t('contactForm.errorMessage'));
      }
    } catch {
      setSubmitStatus('error');
      setErrorMessage(t('contactForm.errorMessage'));
    } finally {
      setIsSubmitting(false);
    }
  };

  return (
    <div className="min-h-screen">
      {/* Hero Section */}
      <div className="py-24 text-center">
        <motion.h1
          initial={{ opacity: 0, y: 20 }}
          animate={{ opacity: 1, y: 0 }}
          className="text-4xl md:text-5xl font-bold text-white mb-4"
        >
          {t('hero.title')}
        </motion.h1>
        <motion.p
          initial={{ opacity: 0, y: 20 }}
          animate={{ opacity: 1, y: 0 }}
          transition={{ delay: 0.1 }}
          className="text-lg text-zinc-400 max-w-2xl mx-auto px-4"
        >
          {t('hero.subtitle')}
        </motion.p>
      </div>

      {/* Main Content */}
      <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 pb-24">
        <div className="grid grid-cols-1 md:grid-cols-2 gap-12">
          {/* Contact Info */}
          <motion.div
            initial={{ opacity: 0, x: -20 }}
            animate={{ opacity: 1, x: 0 }}
            transition={{ delay: 0.2 }}
            className="space-y-8"
          >
            {/* Headshot */}
            <div className="flex items-center gap-6">
              <div className="relative w-24 h-24 rounded-full overflow-hidden border-2 border-zinc-700 flex-shrink-0">
                <Image
                  src="/images/headshot.webp"
                  alt="Damjan Savić - Full-Stack Web Developer"
                  fill
                  sizes="96px"
                  className="object-cover"
                />
              </div>
              <div>
                <h2 className="text-2xl font-bold text-white mb-1">
                  {t('contactInfo.title')}
                </h2>
                <p className="text-zinc-400">
                  {t('contactInfo.description')}
                </p>
              </div>
            </div>

            <div className="space-y-6">
              <motion.div
                initial={{ opacity: 0, y: 10 }}
                animate={{ opacity: 1, y: 0 }}
                transition={{ delay: 0.3 }}
                className="flex items-start gap-4"
              >
                <div className="p-3 bg-zinc-800/50 rounded-lg">
                  <MapPin className="h-6 w-6 text-zinc-400" aria-hidden="true" />
                </div>
                <div>
                  <h3 className="text-sm font-medium text-zinc-300 mb-1">
                    {t('contactInfo.address.label')}
                  </h3>
                  <p className="text-zinc-400">
                    {t('contactInfo.address.value')}
                  </p>
                </div>
              </motion.div>

              <motion.div
                initial={{ opacity: 0, y: 10 }}
                animate={{ opacity: 1, y: 0 }}
                transition={{ delay: 0.4 }}
                className="flex items-start gap-4"
              >
                <div className="p-3 bg-zinc-800/50 rounded-lg">
                  <Phone className="h-6 w-6 text-zinc-400" aria-hidden="true" />
                </div>
                <div>
                  <h3 className="text-sm font-medium text-zinc-300 mb-1">
                    {t('contactInfo.phone.label')}
                  </h3>
                  <a
                    href="tel:+491756950979"
                    className="text-zinc-400 hover:text-white transition-colors"
                  >
                    {t('contactInfo.phone.value')}
                  </a>
                </div>
              </motion.div>

              <motion.div
                initial={{ opacity: 0, y: 10 }}
                animate={{ opacity: 1, y: 0 }}
                transition={{ delay: 0.5 }}
                className="flex items-start gap-4"
              >
                <div className="p-3 bg-zinc-800/50 rounded-lg">
                  <Mail className="h-6 w-6 text-zinc-400" aria-hidden="true" />
                </div>
                <div>
                  <h3 className="text-sm font-medium text-zinc-300 mb-1">
                    {t('contactInfo.email.label')}
                  </h3>
                  <a
                    href="mailto:info@damjan-savic.com"
                    className="text-zinc-400 hover:text-white transition-colors"
                  >
                    {t('contactInfo.email.value')}
                  </a>
                </div>
              </motion.div>
            </div>

            <motion.p
              initial={{ opacity: 0 }}
              animate={{ opacity: 1 }}
              transition={{ delay: 0.6 }}
              className="text-sm text-zinc-500"
            >
              {t('contactInfo.availabilityNote')}
            </motion.p>
          </motion.div>

          {/* Contact Form */}
          <motion.div
            initial={{ opacity: 0, x: 20 }}
            animate={{ opacity: 1, x: 0 }}
            transition={{ delay: 0.3 }}
          >
            <div className="bg-zinc-800/30 border border-zinc-800 rounded-xl p-6 md:p-8">
              <div className="flex items-center gap-2 mb-2">
                <Mail className="h-5 w-5 text-zinc-400" aria-hidden="true" />
                <h2 className="text-xl font-semibold text-white">
                  {t('contactForm.title')}
                </h2>
              </div>
              <p className="text-zinc-400 mb-6">
                {t('contactForm.description')}
              </p>

              <form onSubmit={handleSubmit} className="space-y-6">
                <div className="space-y-4">
                  <div className="space-y-2">
                    <label htmlFor="name" className="block text-sm text-zinc-300">
                      {t('contactForm.name.label')}
                    </label>
                    <input
                      id="name"
                      name="name"
                      type="text"
                      value={formData.name}
                      onChange={handleChange}
                      placeholder={t('contactForm.name.placeholder')}
                      disabled={isSubmitting}
                      aria-required="true"
                      aria-invalid={!!errors.name}
                      aria-describedby={errors.name ? 'name-error' : undefined}
                      className="w-full h-12 px-4 bg-zinc-900/50 border border-zinc-800 rounded-lg text-white placeholder:text-zinc-500 focus:outline-none focus:ring-2 focus:ring-zinc-600 disabled:opacity-50"
                    />
                    {errors.name && (
                      <p id="name-error" role="alert" className="text-sm text-red-400">{errors.name}</p>
                    )}
                  </div>

                  <div className="space-y-2">
                    <label htmlFor="email" className="block text-sm text-zinc-300">
                      {t('contactForm.email.label')}
                    </label>
                    <input
                      id="email"
                      name="email"
                      type="email"
                      value={formData.email}
                      onChange={handleChange}
                      placeholder={t('contactForm.email.placeholder')}
                      disabled={isSubmitting}
                      aria-required="true"
                      aria-invalid={!!errors.email}
                      aria-describedby={errors.email ? 'email-error' : undefined}
                      className="w-full h-12 px-4 bg-zinc-900/50 border border-zinc-800 rounded-lg text-white placeholder:text-zinc-500 focus:outline-none focus:ring-2 focus:ring-zinc-600 disabled:opacity-50"
                    />
                    {errors.email && (
                      <p id="email-error" role="alert" className="text-sm text-red-400">{errors.email}</p>
                    )}
                  </div>

                  <div className="space-y-2">
                    <label htmlFor="message" className="block text-sm text-zinc-300">
                      {t('contactForm.message.label')}
                    </label>
                    <textarea
                      id="message"
                      name="message"
                      value={formData.message}
                      onChange={handleChange}
                      placeholder={t('contactForm.message.placeholder')}
                      rows={6}
                      maxLength={MAX_MESSAGE_LENGTH}
                      disabled={isSubmitting}
                      aria-required="true"
                      aria-invalid={!!errors.message}
                      aria-describedby={errors.message ? 'message-error' : undefined}
                      className="w-full px-4 py-3 bg-zinc-900/50 border border-zinc-800 rounded-lg text-white placeholder:text-zinc-500 focus:outline-none focus:ring-2 focus:ring-zinc-600 disabled:opacity-50 resize-none"
                    />
                    {errors.message && (
                      <p id="message-error" role="alert" className="text-sm text-red-400">{errors.message}</p>
                    )}
                    <div className="flex justify-end">
                      <p
                        className={`text-xs transition-colors ${
                          messageLength > MAX_MESSAGE_LENGTH
                            ? 'text-red-500'
                            : messageLength >= MAX_MESSAGE_LENGTH * 0.8
                            ? 'text-yellow-500'
                            : 'text-zinc-500'
                        }`}
                      >
                        {t('contactForm.characterCounter', { current: messageLength, max: MAX_MESSAGE_LENGTH })}
                      </p>
                    </div>
                  </div>
                </div>

                {/* Rate limit warning - show when attempts are low */}
                {remainingAttempts !== null && remainingAttempts > 0 && remainingAttempts <= 2 && (
                  <motion.div
                    initial={{ opacity: 0, y: 10 }}
                    animate={{ opacity: 1, y: 0 }}
                    className="flex items-center gap-2 p-3 bg-yellow-900/20 border border-yellow-900/50 rounded-lg"
                  >
                    <AlertTriangle className="h-4 w-4 text-yellow-500 flex-shrink-0" />
                    <p className="text-yellow-400 text-sm">
                      {t('contactForm.rateLimit.warning', { count: remainingAttempts })}
                    </p>
                  </motion.div>
                )}

                {submitStatus === 'success' && (
                  <motion.div
                    initial={{ opacity: 0, y: 10 }}
                    animate={{ opacity: 1, y: 0 }}
                    role="alert"
                    aria-live="polite"
                    className="flex items-center gap-2 p-3 bg-green-900/20 border border-green-900/50 rounded-lg"
                  >
                    <CheckCircle2 className="h-4 w-4 text-green-500" aria-hidden="true" />
                    <p className="text-green-400 text-sm">
                      {t('contactForm.successMessage')}
                    </p>
                  </motion.div>
                )}

                {submitStatus === 'error' && (
                  <motion.div
                    initial={{ opacity: 0, y: 10 }}
                    animate={{ opacity: 1, y: 0 }}
                    role="alert"
                    aria-live="assertive"
                    className="p-3 bg-red-900/20 border border-red-900/50 rounded-lg"
                  >
                    <p className="text-red-400 text-sm">
                      {errorMessage || t('contactForm.errorMessage')}
                    </p>
                  </motion.div>
                )}

                <button
                  type="submit"
                  disabled={isSubmitting}
                  aria-busy={isSubmitting}
                  aria-label={isSubmitting ? t('contactForm.submitting') : undefined}
                  className="w-full h-12 bg-zinc-100 hover:bg-white text-zinc-900 font-medium rounded-lg transition-colors duration-300 flex items-center justify-center gap-2 disabled:opacity-50 disabled:cursor-not-allowed"
                >
                  {isSubmitting ? (
                    <Loader2 className="h-5 w-5 animate-spin" aria-hidden="true" />
                  ) : (
                    <>
                      <Send className="h-5 w-5" aria-hidden="true" />
                      {t('contactForm.submit')}
                    </>
                  )}
                </button>
              </form>
            </div>
          </motion.div>
        </div>
      </div>
    </div>
  );
}