// ============================================
// LEGEND - Legenden-Funktionen
// ============================================

// ========== LEGENDE AUSWAHL ==========
function toggleLegendSelection(id) {
    if (selectedSymbols.has(id)) {
        selectedSymbols.delete(id);
    } else {
        selectedSymbols.add(id);

        const item = findSymbol(id);
        if (item && !legendItems.find(l => l.id === id)) {
            legendItems.push({
                id: item.id,
                name: item.name,
                svg: item.svg,
                description: ''
            });
        }
    }

    renderSymbols();
    updateLegendCount();
    saveLegendToStorage();
}

function updateLegendCount() {
    const countEl = document.getElementById('legendCount');
    if (countEl) {
        countEl.textContent = legendItems.length;
    }
}

// ========== LEGENDE MODAL ==========
function openLegendModal() {
    const modal = document.getElementById('legendModal');
    modal.classList.add('active');
    renderLegendEditor();
    updateLegendPreview();
}

function closeLegendModal() {
    const modal = document.getElementById('legendModal');
    modal.classList.remove('active');
}

function renderLegendEditor() {
    const container = document.getElementById('legendItems');

    if (legendItems.length === 0) {
        container.innerHTML = '<div class="legend-empty">Keine Symbole in der Legende. Klicken Sie auf 📑 bei einem Symbol, um es hinzuzufügen.</div>';
        updateLegendPreview();
        return;
    }

    container.innerHTML = legendItems.map((item, index) => `
        <div class="legend-item" data-index="${index}">
            <div class="legend-item-preview">${item.svg}</div>
            <div class="legend-item-content">
                <input type="text" class="legend-item-name" value="${item.name}"
                    oninput="updateLegendItem(${index}, 'name', this.value)" placeholder="Name">
                <input type="text" class="legend-item-desc" value="${item.description || ''}"
                    oninput="updateLegendItem(${index}, 'description', this.value)" placeholder="Beschreibung (optional)">
            </div>
            <div class="legend-item-actions">
                <button type="button" onclick="moveLegendItem(${index}, -1)" title="Nach oben" ${index === 0 ? 'disabled' : ''}>▲</button>
                <button type="button" onclick="moveLegendItem(${index}, 1)" title="Nach unten" ${index === legendItems.length - 1 ? 'disabled' : ''}>▼</button>
                <button type="button" onclick="removeLegendItem(${index})" title="Entfernen" class="btn-remove">✕</button>
            </div>
        </div>
    `).join('');

    updateLegendPreview();
}

function updateLegendItem(index, field, value) {
    if (legendItems[index]) {
        legendItems[index][field] = value;
        saveLegendToStorage();
        updateLegendPreview();
    }
}

function moveLegendItem(index, direction) {
    const newIndex = index + direction;
    if (newIndex >= 0 && newIndex < legendItems.length) {
        const temp = legendItems[index];
        legendItems[index] = legendItems[newIndex];
        legendItems[newIndex] = temp;
        renderLegendEditor();
        saveLegendToStorage();
    }
}

function removeLegendItem(index) {
    const item = legendItems[index];
    if (item) {
        selectedSymbols.delete(item.id);
    }
    legendItems.splice(index, 1);
    renderLegendEditor();
    renderSymbols();
    updateLegendCount();
    saveLegendToStorage();
}

function clearLegend() {
    if (confirm('Möchten Sie die Legende wirklich leeren?')) {
        legendItems = [];
        selectedSymbols.clear();
        renderLegendEditor();
        renderSymbols();
        updateLegendCount();
        saveLegendToStorage();
    }
}

// ========== LEGENDE SPEICHERN/LADEN ==========
function saveLegendToStorage() {
    try {
        localStorage.setItem('gutachter_legende', JSON.stringify(legendItems));
        localStorage.setItem('gutachter_selected', JSON.stringify([...selectedSymbols]));
    } catch (e) {
        console.warn('LocalStorage nicht verfügbar');
    }
}

function loadLegendFromStorage() {
    try {
        const saved = localStorage.getItem('gutachter_legende');
        const savedSelected = localStorage.getItem('gutachter_selected');

        if (saved) {
            legendItems = JSON.parse(saved);
        }
        if (savedSelected) {
            selectedSymbols = new Set(JSON.parse(savedSelected));
        }

        updateLegendCount();
    } catch (e) {
        console.warn('Fehler beim Laden der Legende');
    }
}

// ========== LEGENDE VORSCHAU ==========
function generateLegendSVG() {
    if (legendItems.length === 0) return null;

    const itemHeight = 50;
    const width = 320;
    const height = legendItems.length * itemHeight + 60;

    let svg = `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 ${width} ${height}" width="${width}" height="${height}">
        <rect width="${width}" height="${height}" fill="white"/>
        <text x="20" y="30" font-family="Arial" font-size="18" font-weight="bold">Legende</text>
        <line x1="20" y1="40" x2="${width - 20}" y2="40" stroke="#ccc" stroke-width="1"/>`;

    legendItems.forEach((item, index) => {
        const y = 60 + index * itemHeight;
        svg += `<g transform="translate(20, ${y})">
            <g transform="scale(0.5)">${item.svg.replace(/<svg[^>]*>/, '').replace('</svg>', '')}</g>
            <text x="50" y="20" font-family="Arial" font-size="14" font-weight="bold">${escapeHtml(item.name)}</text>
            ${item.description ? `<text x="50" y="35" font-family="Arial" font-size="11" fill="#666">${escapeHtml(item.description)}</text>` : ''}
        </g>`;
    });

    svg += '</svg>';
    return svg;
}

function updateLegendPreview() {
    const previewBox = document.getElementById('legendPreviewBox');
    if (!previewBox) return;

    if (legendItems.length === 0) {
        previewBox.innerHTML = '<div class="legend-preview-empty">Keine Eintraege vorhanden</div>';
        return;
    }

    const svg = generateLegendSVG();
    if (svg) {
        previewBox.innerHTML = svg;
    }
}

async function copyLegendAsImage() {
    if (legendItems.length === 0) {
        showNotification('Legende ist leer', 'error');
        return;
    }

    const svg = generateLegendSVG();
    if (!svg) return;

    try {
        const canvas = document.createElement('canvas');
        const ctx = canvas.getContext('2d');
        const itemHeight = 50;
        const width = 320;
        const height = legendItems.length * itemHeight + 60;

        canvas.width = width * 2;
        canvas.height = height * 2;
        ctx.scale(2, 2);
        ctx.fillStyle = 'white';
        ctx.fillRect(0, 0, width, height);

        const img = new Image();
        const svgBlob = new Blob([svg], { type: 'image/svg+xml;charset=utf-8' });
        const url = URL.createObjectURL(svgBlob);

        await new Promise((resolve, reject) => {
            img.onload = resolve;
            img.onerror = reject;
            img.src = url;
        });

        ctx.drawImage(img, 0, 0, width, height);
        URL.revokeObjectURL(url);

        canvas.toBlob(async (blob) => {
            try {
                await navigator.clipboard.write([
                    new ClipboardItem({ 'image/png': blob })
                ]);
                showNotification('Legende in Zwischenablage kopiert!');
            } catch (err) {
                const link = document.createElement('a');
                link.href = URL.createObjectURL(blob);
                link.download = 'legende.png';
                link.click();
                showNotification('Legende als PNG heruntergeladen');
            }
        }, 'image/png');
    } catch (err) {
        console.error('Fehler beim Kopieren:', err);
        showNotification('Fehler beim Kopieren', 'error');
    }
}

// Export-Funktionen sind in legend-export.js