'use client';

import React, { useState } from 'react';

const SUPPORT_EMAIL = 'support@motorsignal.app';

const CATEGORIES = [
  'Account & sign-in',
  'Subscription & billing',
  'Group rides',
  'Clubs',
  'Telemetry & ride data',
  'Bug report',
  'Something else',
] as const;

type Errors = { name?: string; email?: string; message?: string };

// Public support contact. There is no public ticket backend, so this never claims a
// ticket was filed: it validates input and opens the visitor's own email client with a
// prefilled message. Email remains the real, working support channel.
export function SupportContactForm() {
  const [name, setName] = useState('');
  const [email, setEmail] = useState('');
  const [category, setCategory] = useState<(typeof CATEGORIES)[number]>(CATEGORIES[0]);
  const [message, setMessage] = useState('');
  const [errors, setErrors] = useState<Errors>({});
  const [opened, setOpened] = useState(false);

  function validate(): Errors {
    const next: Errors = {};
    if (!name.trim()) next.name = 'Please tell us your name.';
    // Pragmatic email check: a single @ with a dot in the domain.
    if (!/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email.trim())) {
      next.email = 'Enter a valid email address so we can reply.';
    }
    if (message.trim().length < 10) {
      next.message = 'Add a few more details (at least 10 characters).';
    }
    return next;
  }

  function handleSubmit(e: React.FormEvent) {
    e.preventDefault();
    const found = validate();
    setErrors(found);
    if (Object.keys(found).length > 0) {
      setOpened(false);
      return;
    }

    const subject = `[${category}] Support request from ${name.trim()}`;
    const body =
      `Name: ${name.trim()}\n` +
      `Email: ${email.trim()}\n` +
      `Category: ${category}\n\n` +
      `${message.trim()}\n`;
    const mailto = `mailto:${SUPPORT_EMAIL}?subject=${encodeURIComponent(subject)}&body=${encodeURIComponent(body)}`;

    // Open the visitor's email client. We do not and cannot confirm delivery here.
    if (typeof window !== 'undefined') {
      window.location.href = mailto;
    }
    setOpened(true);
  }

  const inputClass =
    'w-full px-3.5 py-2.5 rounded-xl bg-surface-container-low border border-outline-variant/40 focus:border-primary-container focus:ring-1 focus:ring-primary-container text-white text-sm outline-none transition placeholder:text-slate-500';

  return (
    <form className="space-y-4 text-left" onSubmit={handleSubmit} noValidate>
      <div className="grid grid-cols-1 sm:grid-cols-2 gap-4">
        <div className="space-y-1.5">
          <label htmlFor="support-name" className="block text-xs font-mono tracking-wide text-on-surface-variant">
            Your name
          </label>
          <input
            id="support-name"
            type="text"
            value={name}
            onChange={(e) => setName(e.target.value)}
            className={inputClass}
            placeholder="Alex Rider"
            aria-invalid={Boolean(errors.name)}
          />
          {errors.name && <p className="form-error" role="alert">{errors.name}</p>}
        </div>

        <div className="space-y-1.5">
          <label htmlFor="support-email" className="block text-xs font-mono tracking-wide text-on-surface-variant">
            Email
          </label>
          <input
            id="support-email"
            type="email"
            value={email}
            onChange={(e) => setEmail(e.target.value)}
            className={inputClass}
            placeholder="you@example.com"
            aria-invalid={Boolean(errors.email)}
          />
          {errors.email && <p className="form-error" role="alert">{errors.email}</p>}
        </div>
      </div>

      <div className="space-y-1.5">
        <label htmlFor="support-category" className="block text-xs font-mono tracking-wide text-on-surface-variant">
          Topic
        </label>
        <select
          id="support-category"
          value={category}
          onChange={(e) => setCategory(e.target.value as (typeof CATEGORIES)[number])}
          className={inputClass}
        >
          {CATEGORIES.map((c) => (
            <option key={c} value={c}>{c}</option>
          ))}
        </select>
      </div>

      <div className="space-y-1.5">
        <label htmlFor="support-message" className="block text-xs font-mono tracking-wide text-on-surface-variant">
          How can we help?
        </label>
        <textarea
          id="support-message"
          value={message}
          onChange={(e) => setMessage(e.target.value)}
          rows={5}
          className={inputClass}
          placeholder="Describe what you ran into, including your device and app version if relevant."
          aria-invalid={Boolean(errors.message)}
        />
        {errors.message && <p className="form-error" role="alert">{errors.message}</p>}
      </div>

      <button type="submit" className="button">Compose support email</button>

      {opened && (
        <p className="form-message" role="status">
          Your email app should have opened with the details filled in. If nothing happened, email{' '}
          <a className="underline" href={`mailto:${SUPPORT_EMAIL}`}>{SUPPORT_EMAIL}</a> directly.
        </p>
      )}

      <p className="form-divider">
        This opens your own email app — we don&rsquo;t submit a ticket on your behalf, so your message
        isn&rsquo;t sent until you send it.
      </p>
    </form>
  );
}