/* ============================================================================
   SoftSPM - obsługa formularzy
   Suwak antybotowy, zgoda marketingowa i wysyłka przez api/send.php.
   Czysty JavaScript, bez zależności.
   ========================================================================= */
(function () {
  'use strict';

  var DICT = {
    pl: {
      slide:       'Przesuń, aby zweryfikować',
      verified:    'Zweryfikowano',
      checking:    'Sprawdzanie...',
      needSlider:  'Najpierw przesuń suwak, aby potwierdzić, że nie jesteś robotem.',
      needConsent: 'Zaznacz zgodę na kontakt, aby wysłać zgłoszenie.',
      sending:     'Wysyłanie...',
      sendLabel:   'Wyślij',
      tokenError:  'Nie udało się przygotować formularza. Odśwież stronę.',
      network:     'Brak połączenia z serwerem. Spróbuj ponownie lub napisz na info@softspm.com.',
      generic:     'Nie udało się wysłać wiadomości. Napisz na info@softspm.com.',
      handleLabel: 'Przesuń suwak w prawo, aby potwierdzić, że nie jesteś robotem'
    },
    en: {
      slide:       'Slide to verify',
      verified:    'Verified',
      checking:    'Checking...',
      needSlider:  'Please slide the control first to confirm you are not a robot.',
      needConsent: 'Please tick the consent box to send the message.',
      sending:     'Sending...',
      sendLabel:   'Send',
      tokenError:  'The form could not be prepared. Please refresh the page.',
      network:     'No connection to the server. Try again or write to info@softspm.com.',
      generic:     'The message could not be sent. Please write to info@softspm.com.',
      handleLabel: 'Slide the control to the right to confirm you are not a robot'
    }
  };

  var lang = (document.documentElement.getAttribute('lang') || 'pl').slice(0, 2).toLowerCase();
  var t = DICT[lang] || DICT.pl;

  /* -- suwak weryfikacyjny -------------------------------------------------- */
  function Slider(root, onVerified) {
    var track  = root.querySelector('[data-verify-track]');
    var fill   = root.querySelector('[data-verify-fill]');
    var handle = root.querySelector('[data-verify-handle]');
    var hint   = root.querySelector('[data-verify-hint]');
    if (!track || !handle) { return null; }

    var pos = 0;
    var done = false;
    var busy = false;
    var pointerId = null;

    handle.setAttribute('aria-label', t.handleLabel);

    function limit() {
      return Math.max(0, track.clientWidth - handle.offsetWidth);
    }

    function place(x) {
      var max = limit();
      pos = Math.max(0, Math.min(max, x));
      handle.style.left = pos + 'px';
      if (fill) { fill.style.width = (pos + handle.offsetWidth) + 'px'; }
      handle.setAttribute('aria-valuenow', max > 0 ? String(Math.round((pos / max) * 100)) : '0');
    }

    function reset() {
      done = false;
      busy = false;
      root.classList.remove('is-verified');
      handle.setAttribute('aria-valuetext', t.slide);
      if (hint) { hint.textContent = t.slide; }
      place(0);
    }

    function complete() {
      if (done || busy) { return; }
      busy = true;
      place(limit());
      if (hint) { hint.textContent = t.checking; }
      onVerified(function (ok) {
        busy = false;
        if (ok) {
          done = true;
          root.classList.add('is-verified');
          handle.setAttribute('aria-valuetext', t.verified);
          if (hint) { hint.textContent = t.verified; }
        } else {
          reset();
        }
      });
    }

    handle.addEventListener('pointerdown', function (event) {
      if (done || busy) { return; }
      pointerId = event.pointerId;
      handle.setPointerCapture(pointerId);
      root.classList.add('is-dragging');
      var offset = event.clientX - handle.getBoundingClientRect().left;

      function move(moveEvent) {
        place(moveEvent.clientX - track.getBoundingClientRect().left - offset);
      }

      function up() {
        handle.removeEventListener('pointermove', move);
        handle.removeEventListener('pointerup', up);
        handle.removeEventListener('pointercancel', up);
        root.classList.remove('is-dragging');
        if (pointerId !== null && handle.hasPointerCapture && handle.hasPointerCapture(pointerId)) {
          handle.releasePointerCapture(pointerId);
        }
        pointerId = null;
        if (pos >= limit() - 2) { complete(); } else { place(0); }
      }

      handle.addEventListener('pointermove', move);
      handle.addEventListener('pointerup', up);
      handle.addEventListener('pointercancel', up);
      event.preventDefault();
    });

    // Obsługa klawiaturą - strzałkami do końca albo klawiszem End.
    handle.addEventListener('keydown', function (event) {
      if (done || busy) { return; }
      var step = limit() / 4;
      var key = event.key;
      if (key === 'ArrowRight' || key === 'ArrowUp') { place(pos + step); }
      else if (key === 'ArrowLeft' || key === 'ArrowDown') { place(pos - step); }
      else if (key === 'End') { place(limit()); }
      else if (key === 'Home') { place(0); }
      else { return; }
      event.preventDefault();
      if (pos >= limit() - 1) { complete(); }
    });

    window.addEventListener('resize', function () {
      place(done ? limit() : pos);
    });

    reset();

    return {
      isVerified: function () { return done; },
      focus: function () { handle.focus(); },
      reset: reset
    };
  }

  /* -- pojedynczy formularz ------------------------------------------------- */
  function initForm(form) {
    var id = form.getAttribute('data-form');
    var endpoint = form.getAttribute('data-endpoint') || 'api/send.php';
    var status = form.querySelector('[data-form-status]');
    var button = form.querySelector('button[type="submit"]');
    var consent = form.querySelector('[data-consent]');
    var verifyRoot = form.querySelector('[data-verify]');
    var buttonLabel = button ? button.textContent : t.sendLabel;

    var token = null;
    var proof = null;
    var sending = false;

    function setStatus(text, kind) {
      if (!status) { return; }
      status.textContent = text || '';
      status.className = 'form-status' + (kind ? ' is-' + kind : '');
    }

    function request(params, done) {
      var url = endpoint + '?' + params;
      var xhrDone = false;
      fetch(url, { credentials: 'same-origin', headers: { 'Accept': 'application/json' } })
        .then(function (response) { return response.json().catch(function () { return {}; }); })
        .then(function (data) { xhrDone = true; done(data && data.ok ? data : null); })
        .catch(function () { if (!xhrDone) { done(null); } });
    }

    // Token pobieramy dopiero, gdy ktoś zacznie korzystać z formularza.
    // Dzięki temu serwer mierzy realny czas wypełniania.
    //
    // Kolejka pending jest istotna: zdarzenie na suwaku potrafi zawołać tę
    // funkcję dwa razy w tej samej chwili. Bez niej powstałyby dwa tokeny,
    // a potwierdzenie dotyczyłoby innego niż ten wysłany razem z formularzem.
    var pending = null;

    function ensureToken(done) {
      if (token) { done(true); return; }
      if (pending) { pending.push(done); return; }
      pending = [done];
      request('action=token&form=' + encodeURIComponent(id), function (data) {
        var queue = pending;
        pending = null;
        if (data && data.token) { token = data.token; }
        for (var i = 0; i < queue.length; i++) { queue[i](!!token); }
      });
    }

    var slider = verifyRoot ? Slider(verifyRoot, function (finish) {
      ensureToken(function (ok) {
        if (!ok) { setStatus(t.tokenError, 'error'); finish(false); return; }
        request('action=confirm&form=' + encodeURIComponent(id) + '&token=' + encodeURIComponent(token), function (data) {
          if (data && data.proof) {
            proof = data.proof;
            setStatus('', null);
            finish(true);
          } else {
            setStatus(t.tokenError, 'error');
            finish(false);
          }
        });
      });
    }) : null;

    // Token bierzemy przy pierwszym dotknięciu formularza - wtedy serwer mierzy
    // realny czas wypełniania, a nie moment przesunięcia suwaka.
    var wake = function () { ensureToken(function () {}); };
    form.addEventListener('focusin', wake);
    if (verifyRoot) {
      verifyRoot.addEventListener('pointerdown', wake);
      verifyRoot.addEventListener('keydown', wake);
    }

    form.addEventListener('submit', function (event) {
      event.preventDefault();
      if (sending) { return; }

      if (slider && !slider.isVerified()) {
        setStatus(t.needSlider, 'error');
        slider.focus();
        return;
      }
      if (consent && !consent.checked) {
        setStatus(t.needConsent, 'error');
        consent.focus();
        return;
      }
      if (!token || !proof) {
        setStatus(t.tokenError, 'error');
        return;
      }

      var payload = {
        form: id,
        token: token,
        proof: proof,
        zgoda: true,
        page: window.location.href
      };
      var fields = form.querySelectorAll('input[name], select[name], textarea[name]');
      for (var i = 0; i < fields.length; i++) {
        var field = fields[i];
        if (field.type === 'checkbox' || field.type === 'radio' || field.type === 'submit') { continue; }
        payload[field.name] = field.value;
      }

      sending = true;
      setStatus(t.sending, 'busy');
      if (button) { button.disabled = true; button.textContent = t.sending; }

      fetch(endpoint, {
        method: 'POST',
        credentials: 'same-origin',
        headers: { 'Content-Type': 'application/json', 'Accept': 'application/json' },
        body: JSON.stringify(payload)
      })
        .then(function (response) {
          return response.json()
            .catch(function () { return { ok: false }; })
            .then(function (data) { return { status: response.status, data: data }; });
        })
        .then(function (result) {
          sending = false;
          if (button) { button.disabled = false; button.textContent = buttonLabel; }
          if (result.data && result.data.ok) {
            form.reset();
            token = null;
            proof = null;
            if (slider) { slider.reset(); }
            setStatus(result.data.message || '', 'ok');
          } else {
            setStatus((result.data && result.data.message) || t.generic, 'error');
            // Token jest jednorazowy i serwer mógł go już zużyć, więc po każdym
            // błędzie bierzemy nowy i prosimy o ponowne przesunięcie suwaka.
            token = null;
            proof = null;
            if (slider) { slider.reset(); }
          }
        })
        .catch(function () {
          sending = false;
          if (button) { button.disabled = false; button.textContent = buttonLabel; }
          setStatus(t.network, 'error');
        });
    });
  }

  function boot() {
    var forms = document.querySelectorAll('form[data-form]');
    for (var i = 0; i < forms.length; i++) { initForm(forms[i]); }
  }

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', boot);
  } else {
    boot();
  }
})();