(function () {

    // ── Status section collapse toggle ────────────────────────────────
    var toggleBtn  = document.getElementById('sys-status-toggle');
    var statusBody = document.getElementById('sys-status-body');
    if (toggleBtn && statusBody) {
        toggleBtn.addEventListener('click', function () {
            var collapsed = statusBody.hidden;
            statusBody.hidden = !collapsed;
            toggleBtn.setAttribute('aria-expanded', collapsed ? 'true' : 'false');
            toggleBtn.textContent = collapsed ? '▲ Réduire' : '▼ Développer';
            try { localStorage.setItem('sys_status_collapsed', collapsed ? '0' : '1'); } catch(e) {}
        });
        try {
            if (localStorage.getItem('sys_status_collapsed') === '1') {
                statusBody.hidden = true;
                toggleBtn.setAttribute('aria-expanded', 'false');
                toggleBtn.textContent = '▼ Développer';
            }
        } catch(e) {}
    }

    // ── fetch()-based tab panel loading ───────────────────────────────
    var panel   = document.getElementById('sys-tab-panel');
    var tabNav  = document.querySelector('.sys-tabs');
    if (!panel || !tabNav || !window.fetch) return;

    var currentTab = panel.dataset.tab;
    var currentN   = panel.dataset.n;

    function loadPanel(tab, n, pushState) {
        var url     = new URL(window.location.href);
        var fragUrl = new URL('/admin/system-fragment.php', window.location.origin);
        fragUrl.searchParams.set('tab', tab);
        fragUrl.searchParams.set('n',   n);

        // Mark the panel as loading
        panel.classList.add('sys-panel-loading');

        fetch(fragUrl.toString(), { credentials: 'same-origin' })
            .then(function (r) {
                if (!r.ok) throw new Error('HTTP ' + r.status);
                return r.text();
            })
            .then(function (html) {
                panel.innerHTML = html;
                panel.dataset.tab = tab;
                panel.dataset.n   = n;
                currentTab = tab;
                currentN   = n;
                panel.classList.remove('sys-panel-loading');

                // Update active tab indicators
                tabNav.querySelectorAll('.sys-tab').forEach(function (a) {
                    var isActive = a.dataset.tab === tab;
                    a.classList.toggle('active', isActive);
                    if (isActive) {
                        a.setAttribute('aria-current', 'page');
                    } else {
                        a.removeAttribute('aria-current');
                    }
                });

                // Re-bind inner controls (lines-select, copy btn)
                bindPanelControls();

                // Update browser URL without reloading
                if (pushState) {
                    url.searchParams.set('tab', tab);
                    url.searchParams.set('n',   n);
                    history.pushState({ tab: tab, n: n }, '', url.toString());
                }
            })
            .catch(function () {
                // Graceful degradation: fall back to full page load
                panel.classList.remove('sys-panel-loading');
                url.searchParams.set('tab', tab);
                url.searchParams.set('n',   n);
                window.location.href = url.toString();
            });
    }

    // Wire tab links
    tabNav.querySelectorAll('.sys-tab').forEach(function (a) {
        a.addEventListener('click', function (e) {
            e.preventDefault();
            var tab = a.dataset.tab;
            if (tab && tab !== currentTab) {
                loadPanel(tab, currentN, true);
            }
        });
    });

    // Handle browser back/forward
    window.addEventListener('popstate', function (e) {
        if (e.state && e.state.tab) {
            loadPanel(e.state.tab, e.state.n || 100, false);
        }
    });

    function bindPanelControls() {
        // Lines-select
        var sel = panel.querySelector('#lines-select');
        if (sel) {
            sel.addEventListener('change', function () {
                loadPanel(currentTab, parseInt(this.value, 10), true);
            });
        }
        // Copy button
        var copyBtn = panel.querySelector('#log-copy-btn');
        var logOut  = panel.querySelector('#log-output');
        if (copyBtn && logOut) {
            copyBtn.addEventListener('click', function () {
                var text = Array.from(logOut.querySelectorAll('.log-line'))
                    .map(function (el) { return el.textContent; })
                    .join('\n');
                if (navigator.clipboard && navigator.clipboard.writeText) {
                    navigator.clipboard.writeText(text).then(function () {
                        copyBtn.textContent = '✓ Copié';
                        copyBtn.classList.add('copied');
                        setTimeout(function () {
                            copyBtn.textContent = 'Copier';
                            copyBtn.classList.remove('copied');
                        }, 2000);
                    }).catch(function () { fallbackCopy(text); });
                } else {
                    fallbackCopy(text);
                }
            });
        }
    }

    // Bind controls already present on first load
    bindPanelControls();

    function fallbackCopy(text) {
        var ta = document.createElement('textarea');
        ta.value = text;
        ta.style.cssText = 'position:fixed;opacity:0;top:0;left:0';
        document.body.appendChild(ta);
        ta.select();
        try { document.execCommand('copy'); } catch (e) {}
        document.body.removeChild(ta);
    }

})();