/**
 * Barrierefreiheits-Manager: Panel mit 4 Schaltern (Kontrast, Focus, Schrift, Animationen).
 *
 * Liegt seit 2026-07-21 in einer eigenen Datei, weil ihn beide Oberflaechen brauchen,
 * das klassische Dashboard (.header-right) und die Studio-Ansicht (.studio-top-right).
 * Vorher steckte er in app.js und fehlte im Studio deshalb komplett.
 */
const A11yManager = {
    _key: 'osint_a11y',
    _isOpen: false,
    _settings: { contrast: false, focus: false, fontsize: false, motion: false },

    init() {
        // Einstellungen aus localStorage laden
        try {
            const saved = JSON.parse(localStorage.getItem(this._key) || '{}');
            Object.keys(this._settings).forEach(k => {
                if (typeof saved[k] === 'boolean') this._settings[k] = saved[k];
            });
        } catch (e) { /* Ungültige Daten ignorieren */ }

        // Button + Panel dynamisch in die Kopfzeile einfügen (vor Theme-Toggle).
        // Beide Oberflaechen benennen ihren rechten Kopfzeilen-Block anders.
        const headerRight = document.querySelector('.header-right, .studio-top-right');
        const themeToggle = document.getElementById('theme-toggle');
        if (!headerRight) return;
        if (document.getElementById('a11y-btn')) return;   // schon vorhanden

        const container = document.createElement('div');
        container.className = 'a11y-center';
        container.innerHTML = `
            <button class="a11y-btn" id="a11y-btn" title="Barrierefreiheit"
                    aria-label="Barrierefreiheit" aria-expanded="false" aria-haspopup="true">
                <svg width="18" height="18" viewBox="0 0 24 24" fill="currentColor" aria-hidden="true">
                    <circle cx="12" cy="4" r="2"/>
                    <path d="M12 8c-3.3 0-6 .5-6 .5v2s2.7-.5 5-.5v3l-3 7h2.5l2.5-5.5 2.5 5.5h2.5l-3-7v-3c2.3 0 5 .5 5 .5v-2S15.3 8 12 8z"/>
                </svg>
            </button>
            <div class="a11y-panel" id="a11y-panel" role="group" aria-label="Barrierefreiheits-Einstellungen" style="display:none;">
                <div class="a11y-panel-title">Barrierefreiheit</div>
                <label class="a11y-option">
                    <input type="checkbox" id="a11y-contrast">
                    <span class="toggle-switch"></span>
                    <span>Hoher Kontrast</span>
                </label>
                <label class="a11y-option">
                    <input type="checkbox" id="a11y-focus">
                    <span class="toggle-switch"></span>
                    <span>Verstärkte Focus-Anzeige</span>
                </label>
                <label class="a11y-option">
                    <input type="checkbox" id="a11y-fontsize">
                    <span class="toggle-switch"></span>
                    <span>Größere Schrift</span>
                </label>
                <label class="a11y-option">
                    <input type="checkbox" id="a11y-motion">
                    <span class="toggle-switch"></span>
                    <span>Animationen aus</span>
                </label>
            </div>
        `;

        if (themeToggle && themeToggle.parentNode === headerRight) {
            headerRight.insertBefore(container, themeToggle);
        } else {
            headerRight.prepend(container);
        }

        // Toggle-Event-Listener
        ['contrast', 'focus', 'fontsize', 'motion'].forEach(key => {
            document.getElementById('a11y-' + key).addEventListener('change', () => this.toggle(key));
        });

        // Button öffnet/schließt Panel
        document.getElementById('a11y-btn').addEventListener('click', (e) => {
            e.stopPropagation();
            this._isOpen ? this._closePanel() : this._openPanel();
        });

        // Klick außerhalb schließt Panel
        document.addEventListener('click', (e) => {
            if (this._isOpen && !container.contains(e.target)) {
                this._closePanel();
            }
        });

        // Keyboard: Esc schließt, Pfeiltasten navigieren
        container.addEventListener('keydown', (e) => {
            if (e.key === 'Escape' && this._isOpen) {
                e.stopPropagation();
                this._closePanel();
                return;
            }
            if (!this._isOpen) return;
            if (e.key === 'ArrowDown' || e.key === 'ArrowUp') {
                e.preventDefault();
                const options = Array.from(document.querySelectorAll('.a11y-option input[type="checkbox"]'));
                const idx = options.indexOf(document.activeElement);
                let next;
                if (e.key === 'ArrowDown') {
                    next = idx < options.length - 1 ? idx + 1 : 0;
                } else {
                    next = idx > 0 ? idx - 1 : options.length - 1;
                }
                options[next].focus();
            }
        });

        // Einstellungen anwenden + Checkboxen synchronisieren
        this._apply();
        this._syncUI();
    },

    toggle(key) {
        this._settings[key] = !this._settings[key];
        this._apply();
        this._syncUI();
        this._save();
    },

    _apply() {
        const root = document.documentElement;
        Object.keys(this._settings).forEach(k => {
            if (this._settings[k]) {
                root.setAttribute('data-a11y-' + k, 'true');
            } else {
                root.removeAttribute('data-a11y-' + k);
            }
        });
    },

    _syncUI() {
        Object.keys(this._settings).forEach(k => {
            const cb = document.getElementById('a11y-' + k);
            if (cb) cb.checked = this._settings[k];
        });
    },

    _save() {
        localStorage.setItem(this._key, JSON.stringify(this._settings));
    },

    _openPanel() {
        this._isOpen = true;
        document.getElementById('a11y-panel').style.display = '';
        document.getElementById('a11y-btn').setAttribute('aria-expanded', 'true');
        // Fokus auf erste Option setzen
        requestAnimationFrame(() => {
            const first = document.querySelector('.a11y-option input[type="checkbox"]');
            if (first) first.focus();
        });
    },

    _closePanel() {
        this._isOpen = false;
        document.getElementById('a11y-panel').style.display = 'none';
        const btn = document.getElementById('a11y-btn');
        btn.setAttribute('aria-expanded', 'false');
        btn.focus();
    }
};