(function () {
    'use strict';

    var REST_URL = (window.careiReservation && window.careiReservation.restUrl) || '/wp-json/carei/v1/';
    var NONCE = (window.careiReservation && window.careiReservation.nonce) || '';

    // ─── API Helpers ──────────────────────────────────────────────

    function apiGet(endpoint) {
        return fetch(REST_URL + endpoint, {
            method: 'GET',
            headers: {
                'X-WP-Nonce': NONCE,
                'Content-Type': 'application/json'
            }
        }).then(function (r) {
            if (!r.ok) throw new Error('API error: ' + r.status);
            return r.json();
        });
    }

    function apiPost(endpoint, data) {
        return fetch(REST_URL + endpoint, {
            method: 'POST',
            headers: {
                'X-WP-Nonce': NONCE,
                'Content-Type': 'application/json'
            },
            body: JSON.stringify(data)
        }).then(function (r) {
            if (!r.ok) throw new Error('API error: ' + r.status);
            return r.json();
        });
    }

    // ─── DOM Refs ─────────────────────────────────────────────────

    var overlay, form, segmentSelect, dateFrom, dateTo, daysCount;
    var pickupSelect, returnSelect, returnWrap, sameReturnCheck;
    var extrasContainer, errorSummary;

    function initRefs() {
        overlay = document.querySelector('[data-carei-modal]');
        form = document.getElementById('carei-reservation-form');
        segmentSelect = document.getElementById('carei-segment');
        dateFrom = document.getElementById('carei-date-from');
        dateTo = document.getElementById('carei-date-to');
        daysCount = document.getElementById('carei-days-count');
        pickupSelect = document.getElementById('carei-pickup-branch');
        returnSelect = document.getElementById('carei-return-branch');
        returnWrap = document.getElementById('carei-return-wrap');
        sameReturnCheck = document.getElementById('carei-same-return');
        extrasContainer = document.getElementById('carei-extras-container');
        errorSummary = document.getElementById('carei-error-summary');
    }

    // ─── Modal Open/Close ─────────────────────────────────────────

    function initModal() {
        var triggers = document.querySelectorAll('[data-carei-open-modal]');
        var closeBtns = document.querySelectorAll('[data-carei-close-modal]');

        triggers.forEach(function (btn) {
            btn.addEventListener('click', function (e) {
                e.preventDefault();
                openModal();
            });
        });

        closeBtns.forEach(function (btn) {
            btn.addEventListener('click', closeModal);
        });

        if (overlay) {
            overlay.addEventListener('click', function (e) {
                if (e.target === overlay) closeModal();
            });
        }

        document.addEventListener('keydown', function (e) {
            if (e.key === 'Escape' && overlay && overlay.classList.contains('is-open')) {
                closeModal();
            }
        });
    }

    var dataLoaded = false;

    function openModal() {
        if (!overlay) return;
        overlay.classList.add('is-open');
        document.body.style.overflow = 'hidden';

        if (!dataLoaded) {
            loadBranches();
            loadAllCarClasses();
            setDefaultDates();
            dataLoaded = true;
        }
    }

    function closeModal() {
        if (!overlay) return;
        overlay.classList.remove('is-open');
        document.body.style.overflow = '';
    }

    // ─── Default Dates ────────────────────────────────────────────

    function setDefaultDates() {
        if (!dateFrom || !dateTo) return;

        var tomorrow = new Date();
        tomorrow.setDate(tomorrow.getDate() + 1);
        tomorrow.setHours(10, 0, 0, 0);

        var dayAfter = new Date();
        dayAfter.setDate(dayAfter.getDate() + 2);
        dayAfter.setHours(10, 0, 0, 0);

        dateFrom.value = formatDatetimeLocal(tomorrow);
        dateTo.value = formatDatetimeLocal(dayAfter);

        updateDaysCount();
    }

    function formatDatetimeLocal(d) {
        var y = d.getFullYear();
        var m = String(d.getMonth() + 1).padStart(2, '0');
        var day = String(d.getDate()).padStart(2, '0');
        var h = String(d.getHours()).padStart(2, '0');
        var min = String(d.getMinutes()).padStart(2, '0');
        return y + '-' + m + '-' + day + 'T' + h + ':' + min;
    }

    // ─── Days Count ───────────────────────────────────────────────

    function updateDaysCount() {
        if (!dateFrom || !dateTo || !daysCount) return;

        var from = new Date(dateFrom.value);
        var to = new Date(dateTo.value);

        if (isNaN(from.getTime()) || isNaN(to.getTime()) || to <= from) {
            daysCount.innerHTML = 'Wybrano: <strong>0 dni</strong>';
            return;
        }

        var diff = Math.ceil((to - from) / (1000 * 60 * 60 * 24));
        var label = diff === 1 ? 'dzień' : 'dni';
        daysCount.innerHTML = 'Wybrano: <strong>' + diff + ' ' + label + '</strong>';
    }

    // ─── Load Branches ────────────────────────────────────────────

    function loadBranches() {
        if (!pickupSelect) return;

        setSelectLoading(pickupSelect, true);

        apiGet('branches')
            .then(function (branches) {
                if (!Array.isArray(branches)) {
                    branches = [];
                }

                populateSelect(pickupSelect, branches.map(function (b) {
                    var label = b.description || b.name;
                    if (b.city) label += ' — ' + b.city;
                    return { value: b.name, label: label };
                }), 'Miejsce odbioru');

                // Copy to return branch
                if (returnSelect) {
                    populateSelect(returnSelect, branches.map(function (b) {
                        var label = b.description || b.name;
                        if (b.city) label += ' — ' + b.city;
                        return { value: b.name, label: label };
                    }), 'Miejsce zwrotu');
                }

                setSelectLoading(pickupSelect, false);
            })
            .catch(function (err) {
                console.error('Failed to load branches:', err);
                setSelectLoading(pickupSelect, false);
            });
    }

    // ─── Load All Car Classes (on modal open) ────────────────────

    function loadAllCarClasses() {
        if (!segmentSelect) return;

        setSelectLoading(segmentSelect, true);

        apiGet('car-classes-all')
            .then(function (classes) {
                if (!Array.isArray(classes) || classes.length === 0) {
                    populateSelect(segmentSelect, [], 'Brak segmentów');
                    setSelectLoading(segmentSelect, false);
                    return;
                }

                populateSelect(segmentSelect, classes.map(function (c) {
                    var val = typeof c === 'string' ? c : (c.name || c);
                    var label = typeof c === 'string' ? ('Segment ' + c) : (c.description || c.name || c);
                    return { value: val, label: label };
                }), 'Wybierz segment pojazdu');

                setSelectLoading(segmentSelect, false);
            })
            .catch(function (err) {
                console.error('Failed to load car classes:', err);
                populateSelect(segmentSelect, [], 'Błąd ładowania');
                setSelectLoading(segmentSelect, false);
            });
    }

    // ─── Load Available Car Classes (filtered by dates+branch) ───

    function loadCarClasses() {
        if (!segmentSelect || !dateFrom || !dateTo || !pickupSelect) return;

        var fromVal = dateFrom.value;
        var toVal = dateTo.value;
        var branch = pickupSelect.value;

        if (!fromVal || !toVal || !branch) return;

        // Convert datetime-local to API format: YYYY-MM-DDTHH:MM:SS
        var apiFrom = fromVal.replace('T', 'T') + ':00';
        var apiTo = toVal.replace('T', 'T') + ':00';

        setSelectLoading(segmentSelect, true);

        apiPost('car-classes', {
            dateFrom: apiFrom,
            dateTo: apiTo,
            branchName: branch
        })
            .then(function (classes) {
                if (!Array.isArray(classes) || classes.length === 0) {
                    populateSelect(segmentSelect, [], 'Brak dostępnych klas');
                    setSelectLoading(segmentSelect, false);
                    return;
                }

                populateSelect(segmentSelect, classes.map(function (c) {
                    // classes might be strings or objects
                    var val = typeof c === 'string' ? c : (c.name || c);
                    var label = typeof c === 'string' ? ('Segment ' + c) : (c.description || c.name || c);
                    return { value: val, label: label };
                }), 'Wybierz segment pojazdu');

                setSelectLoading(segmentSelect, false);
            })
            .catch(function (err) {
                console.error('Failed to load car classes:', err);
                populateSelect(segmentSelect, [], 'Błąd ładowania');
                setSelectLoading(segmentSelect, false);
            });
    }

    // ─── Load Extras from Pricelist ───────────────────────────────

    function loadExtras() {
        if (!segmentSelect || !dateFrom || !dateTo || !pickupSelect || !extrasContainer) return;

        var category = segmentSelect.value;
        var fromVal = dateFrom.value;
        var toVal = dateTo.value;
        var branch = pickupSelect.value;

        if (!category || !fromVal || !toVal || !branch) return;

        var apiFrom = fromVal + ':00';
        var apiTo = toVal + ':00';

        apiPost('pricelist', {
            category: category,
            dateFrom: apiFrom,
            dateTo: apiTo,
            pickUpLocation: branch
        })
            .then(function (pricelists) {
                if (!Array.isArray(pricelists) || pricelists.length === 0) return;

                var pricelist = pricelists[0];
                var items = pricelist.additionalItems;

                if (!Array.isArray(items) || items.length === 0) return;

                extrasContainer.innerHTML = '';

                items.forEach(function (item) {
                    var price = parseFloat(item.price || item.minPrice || 0);
                    var priceLabel = price > 0 ? (price.toFixed(0) + ' zł') : 'Gratis';

                    var card = document.createElement('div');
                    card.className = 'carei-form__extra-card';
                    card.innerHTML =
                        '<label class="carei-form__checkbox-label carei-form__checkbox-label--card">' +
                        '<input type="checkbox" name="extras[]" value="' + escAttr(item.id || item.code) + '" data-price="' + price + '">' +
                        '<span class="carei-form__checkbox-box">' +
                        '<svg width="14" height="14" viewBox="0 0 14 14" fill="none"><path d="M2 7l3.5 3.5L12 4" stroke="#fff" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/></svg>' +
                        '</span>' +
                        '<span class="carei-form__extra-content">' +
                        '<strong>' + escHtml(item.name) + '</strong>' +
                        '<span class="carei-form__extra-price">' + escHtml(priceLabel) + '</span>' +
                        '</span>' +
                        '</label>';

                    extrasContainer.appendChild(card);
                });
            })
            .catch(function (err) {
                console.error('Failed to load pricelist:', err);
                // Keep static fallback extras
            });
    }

    // ─── Select Helpers ───────────────────────────────────────────

    function populateSelect(select, options, placeholder) {
        select.innerHTML = '';

        var ph = document.createElement('option');
        ph.value = '';
        ph.disabled = true;
        ph.selected = true;
        ph.textContent = placeholder || 'Wybierz...';
        select.appendChild(ph);

        options.forEach(function (opt) {
            var o = document.createElement('option');
            o.value = opt.value;
            o.textContent = opt.label;
            select.appendChild(o);
        });
    }

    function setSelectLoading(select, loading) {
        var wrap = select.closest('.carei-form__select-wrap');
        if (!wrap) return;
        if (loading) {
            wrap.classList.add('carei-form__select-wrap--loading');
        } else {
            wrap.classList.remove('carei-form__select-wrap--loading');
        }
    }

    // ─── Same Return Location ─────────────────────────────────────

    function initSameReturn() {
        if (!sameReturnCheck || !returnWrap) return;

        sameReturnCheck.addEventListener('change', function () {
            if (sameReturnCheck.checked) {
                returnWrap.classList.remove('is-visible');
            } else {
                returnWrap.classList.add('is-visible');
            }
        });
    }

    // ─── Validation ───────────────────────────────────────────────

    var requiredFields = [
        { id: 'carei-segment', type: 'select', msg: 'Wybierz segment pojazdu' },
        { id: 'carei-date-from', type: 'input', msg: 'Podaj datę rozpoczęcia' },
        { id: 'carei-date-to', type: 'input', msg: 'Podaj datę zakończenia' },
        { id: 'carei-pickup-branch', type: 'select', msg: 'Wybierz miejsce odbioru' },
        { id: 'carei-firstname', type: 'input', msg: 'Podaj imię' },
        { id: 'carei-lastname', type: 'input', msg: 'Podaj nazwisko' },
        { id: 'carei-email', type: 'email', msg: 'Podaj poprawny adres e-mail' },
        { id: 'carei-phone', type: 'phone', msg: 'Podaj numer telefonu (min. 9 cyfr)' },
        { id: 'carei-privacy', type: 'checkbox', msg: 'Wymagana zgoda na Politykę Prywatności' }
    ];

    function validateForm() {
        var valid = true;

        // Clear previous errors
        form.querySelectorAll('.carei-form__field--error').forEach(function (el) {
            el.classList.remove('carei-form__field--error');
        });
        form.querySelectorAll('.carei-form__checkbox-label--error').forEach(function (el) {
            el.classList.remove('carei-form__checkbox-label--error');
        });
        form.querySelectorAll('.carei-form__error-msg').forEach(function (el) {
            el.remove();
        });

        requiredFields.forEach(function (f) {
            var el = document.getElementById(f.id);
            if (!el) return;

            var hasError = false;

            if (f.type === 'checkbox') {
                if (!el.checked) hasError = true;
            } else if (f.type === 'email') {
                var emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
                if (!el.value.trim() || !emailRegex.test(el.value.trim())) hasError = true;
            } else if (f.type === 'phone') {
                var digits = el.value.replace(/\D/g, '');
                if (digits.length < 9) hasError = true;
            } else if (f.type === 'select') {
                if (!el.value) hasError = true;
            } else {
                if (!el.value.trim()) hasError = true;
            }

            if (hasError) {
                valid = false;
                markFieldError(el, f.msg, f.type);
            }
        });

        // Check dateTo > dateFrom
        if (dateFrom && dateTo && dateFrom.value && dateTo.value) {
            if (new Date(dateTo.value) <= new Date(dateFrom.value)) {
                valid = false;
                markFieldError(dateTo, 'Data zakończenia musi być po dacie rozpoczęcia', 'input');
            }
        }

        // Return branch required if different location
        if (sameReturnCheck && !sameReturnCheck.checked && returnSelect) {
            if (!returnSelect.value) {
                valid = false;
                markFieldError(returnSelect, 'Wybierz miejsce zwrotu', 'select');
            }
        }

        if (errorSummary) {
            errorSummary.style.display = valid ? 'none' : 'block';
        }

        return valid;
    }

    function markFieldError(el, msg, type) {
        if (type === 'checkbox') {
            var label = el.closest('.carei-form__checkbox-label');
            if (label) label.classList.add('carei-form__checkbox-label--error');
        } else {
            var field = el.closest('.carei-form__field');
            if (!field) {
                // For phone in wrap
                field = el.closest('.carei-form__phone-wrap');
                if (field) field = field.closest('.carei-form__field');
            }
            if (field) {
                field.classList.add('carei-form__field--error');
                var errEl = document.createElement('span');
                errEl.className = 'carei-form__error-msg';
                errEl.textContent = msg;
                field.appendChild(errEl);
            }
        }
    }

    function initClearErrors() {
        if (!form) return;
        form.addEventListener('focusin', function (e) {
            var field = e.target.closest('.carei-form__field');
            if (field && field.classList.contains('carei-form__field--error')) {
                field.classList.remove('carei-form__field--error');
                var errMsg = field.querySelector('.carei-form__error-msg');
                if (errMsg) errMsg.remove();
            }
            // Checkbox
            var label = e.target.closest('.carei-form__checkbox-label');
            if (label) label.classList.remove('carei-form__checkbox-label--error');
        });
        // Also on change for checkboxes
        form.addEventListener('change', function (e) {
            if (e.target.type === 'checkbox') {
                var label = e.target.closest('.carei-form__checkbox-label');
                if (label) label.classList.remove('carei-form__checkbox-label--error');
            }
        });
    }

    // ─── Form Submit ──────────────────────────────────────────────

    function initSubmit() {
        if (!form) return;

        form.addEventListener('submit', function (e) {
            e.preventDefault();

            if (!validateForm()) return;

            var formData = collectFormData();
            console.log('Carei Reservation — Form data:', formData);

            // Phase 3 will handle actual API submission
            var submitBtn = form.querySelector('.carei-form__submit');
            if (submitBtn) {
                submitBtn.disabled = true;
                submitBtn.innerHTML =
                    '<svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor"><path d="M2.01 21L23 12 2.01 3 2 10l15 2-15 2z"/></svg> Wysyłanie...';

                // Re-enable after 2s (temporary — Phase 3 will handle properly)
                setTimeout(function () {
                    submitBtn.disabled = false;
                    submitBtn.innerHTML =
                        '<svg width="16" height="16" viewBox="0 0 24 24" fill="currentColor"><path d="M2.01 21L23 12 2.01 3 2 10l15 2-15 2z"/></svg> Wyślij';
                }, 2000);
            }
        });
    }

    function collectFormData() {
        var extras = [];
        form.querySelectorAll('input[name="extras[]"]:checked').forEach(function (cb) {
            extras.push({
                id: cb.value,
                price: parseFloat(cb.getAttribute('data-price') || 0)
            });
        });

        return {
            segment: segmentSelect ? segmentSelect.value : '',
            dateFrom: dateFrom ? dateFrom.value : '',
            dateTo: dateTo ? dateTo.value : '',
            pickupBranch: pickupSelect ? pickupSelect.value : '',
            sameReturn: sameReturnCheck ? sameReturnCheck.checked : true,
            returnBranch: (sameReturnCheck && !sameReturnCheck.checked && returnSelect) ? returnSelect.value : '',
            extras: extras,
            firstName: val('carei-firstname'),
            lastName: val('carei-lastname'),
            email: val('carei-email'),
            phone: '+48' + (document.getElementById('carei-phone') ? document.getElementById('carei-phone').value.replace(/\D/g, '') : ''),
            message: val('carei-message'),
            privacy: document.getElementById('carei-privacy') ? document.getElementById('carei-privacy').checked : false
        };
    }

    function val(id) {
        var el = document.getElementById(id);
        return el ? el.value.trim() : '';
    }

    // ─── Event Listeners for Dynamic Loading ──────────────────────

    function initDynamicLoading() {
        // Date change → update days count
        if (dateFrom) dateFrom.addEventListener('change', updateDaysCount);
        if (dateTo) dateTo.addEventListener('change', updateDaysCount);

        // When segment + dates + branch all set → load extras from pricelist
        if (segmentSelect) segmentSelect.addEventListener('change', loadExtras);
        if (pickupSelect) pickupSelect.addEventListener('change', loadExtras);
        if (dateFrom) dateFrom.addEventListener('change', loadExtras);
        if (dateTo) dateTo.addEventListener('change', loadExtras);
    }

    // ─── HTML Escape Helpers ──────────────────────────────────────

    function escHtml(str) {
        var div = document.createElement('div');
        div.textContent = str || '';
        return div.innerHTML;
    }

    function escAttr(str) {
        return (str || '').replace(/&/g, '&amp;').replace(/"/g, '&quot;').replace(/'/g, '&#39;').replace(/</g, '&lt;').replace(/>/g, '&gt;');
    }

    // ─── Init ─────────────────────────────────────────────────────

    function init() {
        initRefs();
        if (!overlay || !form) return;
        initModal();
        initSameReturn();
        initDynamicLoading();
        initClearErrors();
        initSubmit();
    }

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