(() => {
    'use strict';

    const PTA = window.PTA;
    if (!PTA) throw new Error('PTA core doit être chargé avant vacation-calendar.js');

    const { escapeHtml, readJsonResponse, apiErrorMessage, formatDate } = PTA.utils;
    let previewPeriods = [];

    const elements = () => ({
        academy: document.querySelector('#vacation-academy'),
        calendarYear: document.querySelector('#vacation-calendar-year'),
        previewButton: document.querySelector('#preview-vacations'),
        previewMessage: document.querySelector('#vacation-preview-message'),
        previewPanel: document.querySelector('#vacation-preview-panel'),
        previewBody: document.querySelector('#vacation-preview-body'),
        selectAll: document.querySelector('#vacation-select-all'),
        saveSelected: document.querySelector('#save-selected-vacations'),
        savedBody: document.querySelector('#vacation-saved-body'),
        savedMessage: document.querySelector('#vacation-saved-message'),
        refresh: document.querySelector('#refresh-vacations'),
        manualForm: document.querySelector('#manual-vacation-form'),
        manualMessage: document.querySelector('#manual-vacation-message'),
    });

    function setMessage(element, text = '', type = 'info') {
        if (!element) return;
        element.className = text ? `message message-${type}` : 'message';
        element.textContent = text;
    }

    function sourceLabel(source) {
        return source === 'DATA_GOUV' ? 'API officielle' : 'Saisie manuelle';
    }

    function renderPreview() {
        const el = elements();
        if (!el.previewBody || !el.previewPanel) return;

        if (!previewPeriods.length) {
            el.previewBody.innerHTML = '<tr><td colspan="5"><div class="empty-state">Aucune période proposée.</div></td></tr>';
            el.previewPanel.hidden = false;
            return;
        }

        el.previewBody.innerHTML = previewPeriods.map((period, index) => `
            <tr class="vacation-preview-row" data-index="${index}">
                <td><input class="vacation-import-check" type="checkbox" aria-label="Importer ${escapeHtml(period.libelle)}"></td>
                <td>
                    <input class="vacation-preview-label" type="text" maxlength="150" value="${escapeHtml(period.libelle)}">
                    <small>${escapeHtml(period.annee_scolaire || '')}</small>
                </td>
                <td><input class="vacation-preview-start" type="date" value="${escapeHtml(period.date_debut)}"></td>
                <td>
                    <input class="vacation-preview-end" type="date" value="${escapeHtml(period.date_fin)}">
                    ${period.date_reprise_api ? `<small>Reprise API : ${escapeHtml(formatDate(period.date_reprise_api))}</small>` : ''}
                </td>
                <td>${escapeHtml([period.zone, period.academie].filter(Boolean).join(' · ') || 'Non précisé')}</td>
            </tr>
        `).join('');
        el.previewPanel.hidden = false;
        if (el.selectAll) el.selectAll.checked = false;
    }

    async function preview() {
        const el = elements();
        const academy = el.academy?.value.trim() || '';
        const calendarYear = String(el.calendarYear?.value || '').trim();
        if (!academy || !/^\d{4}$/.test(calendarYear)) {
            setMessage(el.previewMessage, 'Renseignez une académie et une année civile au format 2026.', 'warning');
            return;
        }

        el.previewButton.disabled = true;
        setMessage(el.previewMessage, 'Consultation de l’API officielle en cours…', 'info');
        if (el.previewPanel) el.previewPanel.hidden = true;

        try {
            const params = new URLSearchParams({ academy, year: calendarYear });
            const response = await fetch(`api/preview_school_holidays.php?${params.toString()}`);
            const data = await readJsonResponse(response);
            if (!response.ok) throw new Error(apiErrorMessage(data, 'Impossible de consulter le calendrier scolaire.'));

            previewPeriods = Array.isArray(data.periods) ? data.periods : [];
            renderPreview();
            const warnings = Array.isArray(data.warnings) ? data.warnings.filter(Boolean) : [];
            const baseMessage = data.message || `${previewPeriods.length} période(s) proposée(s). Aucune donnée n’a encore été enregistrée.`;
            const fullMessage = warnings.length ? `${baseMessage} Attention : ${warnings.join(' ')}` : baseMessage;
            setMessage(el.previewMessage, fullMessage, warnings.length ? 'warning' : (previewPeriods.length ? 'success' : 'warning'));
        } catch (error) {
            previewPeriods = [];
            setMessage(el.previewMessage, error.message, 'error');
        } finally {
            el.previewButton.disabled = false;
        }
    }

    function selectedPreviewPeriods() {
        const el = elements();
        return Array.from(el.previewBody?.querySelectorAll('.vacation-preview-row') || [])
            .filter((row) => row.querySelector('.vacation-import-check')?.checked)
            .map((row) => {
                const source = previewPeriods[Number(row.dataset.index)] || {};
                return {
                    libelle: row.querySelector('.vacation-preview-label')?.value.trim() || '',
                    date_debut: row.querySelector('.vacation-preview-start')?.value || '',
                    date_fin: row.querySelector('.vacation-preview-end')?.value || '',
                    annee_scolaire: source.annee_scolaire || '',
                    academie: source.academie || elements().academy?.value.trim() || '',
                    zone: source.zone || '',
                    source: 'DATA_GOUV',
                };
            });
    }

    async function savePeriods(periods, messageElement) {
        const response = await fetch('api/save_vacation_periods.php', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({
                csrf_token: window.PTA_CONFIG.csrfToken,
                periods,
            }),
        });
        const data = await readJsonResponse(response);
        if (!response.ok) throw new Error(apiErrorMessage(data, 'Impossible d’enregistrer les périodes.'));
        setMessage(messageElement, data.message, 'success');
        await loadSaved();
        return data;
    }

    async function saveSelected() {
        const el = elements();
        const periods = selectedPreviewPeriods();
        if (!periods.length) {
            setMessage(el.previewMessage, 'Cochez au moins une période avant de l’enregistrer.', 'warning');
            return;
        }

        el.saveSelected.disabled = true;
        try {
            await savePeriods(periods, el.previewMessage);
            el.previewBody?.querySelectorAll('.vacation-import-check').forEach((checkbox) => { checkbox.checked = false; });
            if (el.selectAll) el.selectAll.checked = false;
        } catch (error) {
            setMessage(el.previewMessage, error.message, 'error');
        } finally {
            el.saveSelected.disabled = false;
        }
    }

    async function saveManual(event) {
        event.preventDefault();
        const el = elements();
        const submit = el.manualForm?.querySelector('button[type="submit"]');
        const period = {
            libelle: document.querySelector('#manual-vacation-label')?.value.trim() || '',
            date_debut: document.querySelector('#manual-vacation-start')?.value || '',
            date_fin: document.querySelector('#manual-vacation-end')?.value || '',
            annee_scolaire: document.querySelector('#manual-vacation-school-year')?.value.trim() || '',
            academie: document.querySelector('#manual-vacation-academy')?.value.trim() || '',
            zone: document.querySelector('#manual-vacation-zone')?.value.trim() || '',
            source: 'MANUEL',
        };

        if (period.date_debut && period.date_fin && period.date_fin < period.date_debut) {
            setMessage(el.manualMessage, 'La date de fin doit être postérieure ou égale à la date de début.', 'warning');
            return;
        }

        if (submit) submit.disabled = true;
        try {
            await savePeriods([period], el.manualMessage);
            document.querySelector('#manual-vacation-label').value = '';
            document.querySelector('#manual-vacation-start').value = '';
            document.querySelector('#manual-vacation-end').value = '';
            document.querySelector('#manual-vacation-zone').value = '';
        } catch (error) {
            setMessage(el.manualMessage, error.message, 'error');
        } finally {
            if (submit) submit.disabled = false;
        }
    }

    function renderSaved(periods) {
        const el = elements();
        if (!el.savedBody) return;
        if (!periods.length) {
            el.savedBody.innerHTML = '<tr><td colspan="6"><div class="empty-state">Aucune période de vacances n’est encore enregistrée.</div></td></tr>';
            return;
        }

        el.savedBody.innerHTML = periods.map((period) => `
            <tr data-period-id="${Number(period.id_periode)}">
                <td><strong>${escapeHtml(period.libelle)}</strong></td>
                <td>${escapeHtml(formatDate(period.date_debut))} → ${escapeHtml(formatDate(period.date_fin))}</td>
                <td>${escapeHtml(period.annee_scolaire || '')}</td>
                <td>${escapeHtml([period.academie, period.zone].filter(Boolean).join(' · ') || 'Non précisé')}</td>
                <td><span class="vacation-source-badge">${escapeHtml(sourceLabel(period.source))}</span></td>
                <td><button type="button" class="button button-danger delete-vacation-period">Supprimer</button></td>
            </tr>
        `).join('');
    }

    async function loadSaved() {
        const el = elements();
        try {
            const response = await fetch('api/vacation_periods.php');
            const data = await readJsonResponse(response);
            if (!response.ok) throw new Error(apiErrorMessage(data, 'Impossible de charger les périodes enregistrées.'));
            renderSaved(Array.isArray(data.periods) ? data.periods : []);
            setMessage(el.savedMessage, '', 'info');
        } catch (error) {
            setMessage(el.savedMessage, error.message, 'error');
        }
    }

    async function deletePeriod(button) {
        const row = button.closest('tr[data-period-id]');
        const id = Number(row?.dataset.periodId || 0);
        if (!id || !confirm('Supprimer cette période de vacances ? Les journées concernées seront à nouveau considérées comme périscolaires.')) return;

        button.disabled = true;
        try {
            const response = await fetch('api/delete_vacation_period.php', {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify({
                    csrf_token: window.PTA_CONFIG.csrfToken,
                    period_id: id,
                }),
            });
            const data = await readJsonResponse(response);
            if (!response.ok) throw new Error(apiErrorMessage(data, 'Suppression impossible.'));
            setMessage(elements().savedMessage, data.message, 'success');
            await loadSaved();
        } catch (error) {
            setMessage(elements().savedMessage, error.message, 'error');
            button.disabled = false;
        }
    }

    function init() {
        const el = elements();
        el.previewButton?.addEventListener('click', preview);
        el.saveSelected?.addEventListener('click', saveSelected);
        el.refresh?.addEventListener('click', loadSaved);
        el.manualForm?.addEventListener('submit', saveManual);
        el.selectAll?.addEventListener('change', () => {
            el.previewBody?.querySelectorAll('.vacation-import-check').forEach((checkbox) => {
                checkbox.checked = el.selectAll.checked;
            });
        });
        el.savedBody?.addEventListener('click', (event) => {
            const button = event.target.closest('.delete-vacation-period');
            if (button) deletePeriod(button);
        });

        loadSaved();
    }

    PTA.modules.vacationCalendar = { init, loadSaved, preview };
})();