/**
 * TPU Survey - Teacher Dashboard Logic
 */

let teacherSurveys = [];

async function initTeacher() {
    const loggedIn = await Auth.check();
    if (!loggedIn || !Auth.isTeacher()) {
        if (Auth.isAdmin()) {
            window.location.href = 'admin.html';
            return;
        }
        window.location.href = 'index.html';
        return;
    }

    document.getElementById('userName').textContent = Auth.user.full_name;
    document.getElementById('userRole').textContent = 'อาจารย์ / เจ้าของโครงการ';
    document.getElementById('userAvatar').textContent = Auth.user.full_name.charAt(0);

    showTeacherView('mySurveys');
}

function showTeacherView(view) {
    document.querySelectorAll('.view-section').forEach(s => s.classList.add('hidden'));
    document.getElementById(`view-${view}`)?.classList.remove('hidden');
    
    document.querySelectorAll('.nav-item').forEach(n => n.classList.remove('active'));
    document.querySelector(`.nav-item[data-view="${view}"]`)?.classList.add('active');

    const titles = { mySurveys: 'แบบสอบถามของฉัน', profile: 'ข้อมูลส่วนตัว' };
    document.getElementById('pageTitle').textContent = titles[view] || '';

    if (view === 'mySurveys') loadTeacherSurveys();
    else if (view === 'profile') loadProfile();
}

async function loadTeacherSurveys() {
    try {
        const data = await API.get('surveys.php?action=list');
        teacherSurveys = data.surveys || [];
        renderTeacherSurveys();
    } catch (err) {
        Toast.error(err.message);
    }
}

function renderTeacherSurveys() {
    const container = document.getElementById('teacherSurveysList') || document.getElementById('teacherSurveysBody');
    if (!container) return;

    if (teacherSurveys.length === 0) {
        const emptyHtml = `
            <div class="card-tapi p-8 text-center bg-white rounded-lg border border-slate-200">
                <i class="fas fa-clipboard-list text-4xl text-blue-300 mb-3 block"></i>
                <p class="text-gray-600 font-bold">ยังไม่มีแบบสอบถาม กดปุ่ม "สร้างแบบสอบถาม" เพื่อเริ่มต้น</p>
            </div>
        `;
        if (container.tagName === 'TBODY') {
            container.innerHTML = `<tr><td colspan="5" class="text-center text-muted" style="padding:40px">ยังไม่มีแบบสอบถาม กดปุ่ม "สร้างแบบสอบถาม" เพื่อเริ่มต้น</td></tr>`;
        } else {
            container.innerHTML = emptyHtml;
        }
        return;
    }

    const statusMap = {
        active: { label: 'เปิดใช้งาน', bg: 'bg-emerald-100 text-emerald-800 border-emerald-300' },
        draft: { label: 'ฉบับร่าง', bg: 'bg-amber-100 text-amber-800 border-amber-300' },
        closed: { label: 'ปิดแล้ว', bg: 'bg-rose-100 text-rose-800 border-rose-300' }
    };

    container.innerHTML = teacherSurveys.map(s => {
        const st = statusMap[s.status] || { label: s.status || 'เปิดใช้งาน', bg: 'bg-emerald-100 text-emerald-800 border-emerald-300' };

        return `
            <div class="card-tapi p-3.5 rounded-xl bg-white flex flex-col lg:flex-row justify-between items-start lg:items-center gap-3 transition-all hover:shadow-md border border-slate-200">
                <div class="flex flex-col sm:flex-row sm:items-center gap-2.5 flex-1 min-w-0">
                    <span class="px-2 py-0.5 text-[11px] font-extrabold rounded border whitespace-nowrap self-start sm:self-auto ${st.bg}">${st.label}</span>
                    <div class="space-y-0.5 flex-1 min-w-0">
                        <h4 class="font-bold text-xs sm:text-sm text-blue-950 truncate" title="${escapeHtml(s.title)}">
                            ${escapeHtml(s.title)}
                        </h4>
                        <div class="flex items-center gap-3 text-[11px] text-gray-500 font-semibold flex-wrap">
                            <span><i class="fas fa-comments text-blue-600 mr-1"></i> ${s.response_count || 0} คำตอบ</span>
                            <span><i class="fas fa-calendar-alt text-amber-600 mr-1"></i> ${formatDate(s.created_at)}</span>
                        </div>
                    </div>
                </div>
                <div class="flex flex-wrap lg:flex-nowrap gap-1.5 items-center flex-shrink-0 w-full lg:w-auto overflow-x-auto pb-1 lg:pb-0">
                    <button onclick="teacherEditSurvey(${s.id})" class="btn-action btn-action-edit" title="แก้ไขแบบสอบถาม">
                        <i class="fas fa-edit"></i> แก้ไข
                    </button>
                    <button onclick="teacherDuplicateSurvey(${s.id})" class="btn-action btn-action-copy" title="คัดลอกแบบสอบถาม">
                        <i class="fas fa-copy"></i> คัดลอก
                    </button>
                    <button onclick="teacherGenerateLink(${s.id})" class="btn-action btn-action-link" title="ลิงก์และ QR Code">
                        <i class="fas fa-link"></i> ลิงก์
                    </button>
                    <button onclick="showImportResponsesModal(${s.id}, '${escapeHtml(s.title)}')" class="btn-action btn-action-import" title="นำเข้าคำตอบจาก CSV">
                        <i class="fas fa-file-import"></i> นำเข้า
                    </button>
                    <button onclick="teacherViewStats(${s.id})" class="btn-action btn-action-stats" title="ผลสถิติ">
                        <i class="fas fa-chart-pie"></i> สถิติ
                    </button>
                    <button onclick="teacherDeleteSurvey(${s.id}, '${escapeHtml(s.title)}')" class="btn-action btn-action-delete" title="ลบแบบสอบถาม">
                        <i class="fas fa-trash-alt"></i> ลบ
                    </button>
                </div>
            </div>
        `;
    }).join('');
}

async function teacherDeleteSurvey(id, title) {
    if (!confirm(`คุณต้องการลบแบบสอบถาม "${title}" ใช่หรือไม่?`)) return;
    try {
        await API.get(`surveys.php?action=delete&id=${id}`);
        Toast.success('ลบแบบสอบถามเรียบร้อยแล้ว');
        loadTeacherSurveys();
    } catch (err) {
        Toast.error(err.message);
    }
}

function showTeacherCreateModal() {
    const html = `
        <form id="teacherSurveyForm">
            <div class="form-group">
                <label class="form-label">ชื่อแบบสอบถาม *</label>
                <input type="text" class="form-input" name="title" required placeholder="เช่น แบบประเมินความพึงพอใจโครงการ...">
            </div>
            <div class="form-group">
                <label class="form-label">รายละเอียด</label>
                <textarea class="form-input" name="description" placeholder="คำอธิบายเพิ่มเติม"></textarea>
            </div>
        </form>
    `;
    const footer = `
        <button class="btn btn-secondary" onclick="Modal.hide('tCreateModal');document.getElementById('tCreateModal').remove();">ยกเลิก</button>
        <button class="btn btn-primary" onclick="submitTeacherCreate()">สร้างแบบสอบถาม (ใช้ 3 ส่วนมาตรฐาน)</button>
    `;
    Modal.create('สร้างแบบสอบถามใหม่', html, footer);
    document.querySelector('.modal-overlay:last-child').id = 'tCreateModal';
}

async function submitTeacherCreate() {
    const form = document.getElementById('teacherSurveyForm');
    const fd = new FormData(form);
    const data = Object.fromEntries(fd);

    if (!data.title) { Toast.warning('กรุณากรอกชื่อ'); return; }

    // Pre-fill 3 sections
    data.sections = [
        {
            section_number: 1,
            title: 'ส่วนที่ ข้อมูลทั่วไป',
            category: 'general',
            questions: [
                { question_text: 'เพศ', question_type: 'radio', options: ['ชาย', 'หญิง'], is_required: 1 },
                { question_text: 'ช่วงอายุ', question_type: 'dropdown', options: ['18-25 ปี', '26-35 ปี', '36-45 ปี', '46-55 ปี', '56 ปีขึ้นไป'], is_required: 1 }
            ]
        },
        {
            section_number: 2,
            title: 'ส่วนที่ การประเมินความพึงพอใจ',
            category: 'rating',
            questions: [
                { question_text: 'ด้านเนื้อหาของการจัดโครงการ', question_type: 'radio', is_required: 1 },
                { question_text: 'ด้านวิทยากร / ผู้บรรยาย', question_type: 'radio', is_required: 1 }
            ]
        },
        {
            section_number: 3,
            title: 'ส่วนที่ ข้อเสนอแนะอื่นๆ',
            category: 'suggestions',
            questions: [
                { question_text: 'ข้อเสนอแนะเพิ่มเติม', question_type: 'text', is_required: 0 }
            ]
        }
    ];

    try {
        const result = await API.post('surveys.php?action=create', data);
        Toast.success('สร้างแบบสอบถามสำเร็จ');
        Modal.hide('tCreateModal');
        document.getElementById('tCreateModal').remove();
        loadTeacherSurveys();
        setTimeout(() => teacherEditSurvey(result.id), 500);
    } catch (err) {
        Toast.error(err.message);
    }
}

function teacherEditSurvey(id) {
    window.open(`edit.html?id=${id}`, '_blank');
}

function buildTeacherQEditor(si, qi, q = {}) {
    const qType = q.question_type || 'radio';
    const qText = q.question_text || '';
    const qOptions = Array.isArray(q.options) ? q.options.join('\n') : '';
    const showOptions = ['radio', 'checkbox', 'dropdown'].includes(qType);

    const qDescription = q.description || '';
    
    return `
        <div class="question-builder">
            <div class="qb-header">
                <span class="qb-handle">⋮⋮</span>
                <span class="text-sm fw-600 q-number-label">คำถาม</span>
                <div class="qb-actions">
                    <button type="button" class="btn btn-ghost btn-sm" onclick="addTeacherQ(${si}, this.closest('.question-builder'))" title="แทรกคำถามใต้ข้อนี้">➕ แทรก</button>
                    <button type="button" class="btn btn-ghost btn-sm text-danger" onclick="removeTeacherQ(this, ${si})" title="ลบคำถาม">🗑️ ลบ</button>
                </div>
            </div>
            <div class="form-group">
                <label class="form-label">คำถาม / ข้อความ</label>
                <input type="text" class="form-input q-text-input" value="${escapeHtml(qText)}" placeholder="พิมพ์คำถาม...">
            </div>
            <div class="form-group">
                <label class="form-label">รายละเอียดเพิ่มเติม (คำใบ้/คำอธิบาย - ไม่บังคับ)</label>
                <input type="text" class="form-input q-desc-input" value="${escapeHtml(qDescription)}" placeholder="เช่น กรุณาระบุเป็นภาษาไทย">
            </div>
            <div class="form-group">
                <label class="form-label">ประเภทคำถาม</label>
                <select class="form-input q-type-select" onchange="toggleTeacherOptions(this)">
                    <option value="radio" ${qType==='radio'?'selected':''}>📊 ระดับ 1-5</option>
                    <option value="text" ${qType==='text'?'selected':''}>📝 ข้อความ</option>
                    <option value="dropdown" ${qType==='dropdown'?'selected':''}>📋 Dropdown</option>
                    <option value="checkbox" ${qType==='checkbox'?'selected':''}>☑️ Checkbox</option>
                </select>
            </div>
            <div class="form-group q-options-group" style="${showOptions ? '' : 'display:none;'}">
                <label class="form-label">ตัวเลือก (1 รายการต่อบรรทัด)</label>
                <textarea class="form-input q-options-input" placeholder="ตัวเลือกที่ 1\nตัวเลือกที่ 2" rows="3">${escapeHtml(qOptions)}</textarea>
                <small class="text-muted">เว้นว่างสำหรับระดับ 1-5 (Radio)</small>
            </div>
        </div>
    `;
}

function addTeacherSection() {
    const container = document.getElementById('additionalTeacherSections');
    if (!container) return;
    const si = document.querySelectorAll('.card[data-section]').length;
    
    const html = `
        <div class="card mb-24" data-section="${si}">
            <div class="card-header d-flex justify-between items-center">
                <input type="text" class="form-input" style="font-weight:700;font-size:16px;border:none;padding:4px 0;background:transparent;" 
                       value="ส่วนที่ ข้อมูลเพิ่มเติม" data-field="section-title-${si}">
                <button type="button" class="btn btn-ghost btn-sm text-danger" onclick="this.closest('.card').remove()">🗑️ ลบส่วนนี้</button>
            </div>
            <div class="card-body">
                <div id="t-questions-${si}"></div>
                <button type="button" class="btn btn-secondary btn-sm mt-16" onclick="addTeacherQ(${si})">+ เพิ่มคำถาม</button>
            </div>
        </div>
    `;
    container.insertAdjacentHTML('beforeend', html);
    // Add one initial question to the new section
    addTeacherQ(si);
}

function toggleTeacherOptions(select) {
    const group = select.closest('.question-builder').querySelector('.q-options-group');
    if (['radio', 'checkbox', 'dropdown'].includes(select.value)) {
        group.style.display = 'block';
    } else {
        group.style.display = 'none';
    }
}

function addTeacherQ(si, afterEl = null) {
    const container = document.getElementById(`t-questions-${si}`);
    if (!container) return;
    
    // Create temporary div to parse HTML
    const tempDiv = document.createElement('div');
    tempDiv.innerHTML = buildTeacherQEditor(si, 0); 
    const newQ = tempDiv.firstElementChild;
    
    if (afterEl) {
        afterEl.after(newQ);
    } else {
        container.appendChild(newQ);
    }
    
    reindexTeacherQuestions(si);
}

function removeTeacherQ(btn, si) {
    if (!confirm('ยืนยันลบคำถามนี้?')) return;
    btn.closest('.question-builder').remove();
    reindexTeacherQuestions(si);
}

function reindexTeacherQuestions(si) {
    const container = document.getElementById(`t-questions-${si}`);
    if (!container) return;
    container.querySelectorAll('.question-builder').forEach((qEl, idx) => {
        const label = qEl.querySelector('.q-number-label');
        if (label) label.textContent = `คำถาม`;
    });
}

async function submitTeacherEdit() {
    const form = document.getElementById('tEditForm');
    const id = form.querySelector('[name="id"]').value;
    const title = form.querySelector('[name="title"]').value;
    const description = form.querySelector('[name="description"]').value;

    const sections = [];
    form.querySelectorAll('.card[data-section]').forEach((sectionEl, si) => {
        const sTitleInput = sectionEl.querySelector('input[data-field^="section-title"]');
        const sCategorySelect = sectionEl.querySelector('select[data-field^="section-category"]');
        const sTitle = sTitleInput ? sTitleInput.value : `ส่วนที่ ${si+1}`;
        const sCategory = sCategorySelect ? sCategorySelect.value : 'rating';
        const questions = [];
        
        sectionEl.querySelectorAll('.question-builder').forEach((qEl, qi) => {
            const qTextInput = qEl.querySelector('.q-text-input');
            const qDescInput = qEl.querySelector('.q-desc-input');
            const qTypeSelect = qEl.querySelector('.q-type-select');
            const qOptionsArea = qEl.querySelector('.q-options-input');
            
            const qText = qTextInput ? qTextInput.value : '';
            const qDescription = qDescInput ? qDescInput.value : '';
            const qType = qTypeSelect ? qTypeSelect.value : 'radio';
            const qOptionsRaw = qOptionsArea ? qOptionsArea.value : '';
            
            const options = qOptionsRaw.split('\n').map(o => o.trim()).filter(o => o !== '');

            if (qText.trim()) {
                questions.push({ 
                    question_text: qText.trim(), 
                    description: qDescription.trim() || null,
                    question_type: qType, 
                    order_num: qi, 
                    is_required: 1,
                    options: options.length > 0 ? options : null
                });
            }
        });

        sections.push({ section_number: si + 1, title: sTitle, category: sCategory, questions });
    });

    try {
        await API.post('surveys.php?action=update', { id: parseInt(id), title, description, sections });
        Toast.success('บันทึกสำเร็จ');
        Modal.hide('tEditModal');
        document.getElementById('tEditModal').remove();
        loadTeacherSurveys();
    } catch (err) {
        Toast.error(err.message);
    }
}

async function teacherDuplicateSurvey(id) {
    if (!confirm('ยืนยันสร้างสำเนาแบบสอบถามนี้?')) return;
    try {
        await API.post('surveys.php?action=duplicate', { id });
        Toast.success('คัดลอกสำเร็จ');
        loadTeacherSurveys();
    } catch (err) {
        Toast.error(err.message);
    }
}

async function teacherGenerateLink(id) {
    try {
        const data = await API.post('surveys.php?action=generateLink', { id });
        const basePath = window.location.pathname.includes('/survey') ? '/survey' : '';
        const fullUrl = data.full_url || `${window.location.origin}${basePath}/respond.php?link=${data.unique_link}`;

        // Find survey title
        const survey = teacherSurveys.find(s => s.id == id);
        const surveyTitle = survey ? survey.title : 'แบบสอบถาม';

        const html = `
            <div class="qr-link-container">
                <div class="qr-link-section">
                    <div class="qr-link-label">🔗 ลิงก์แบบสอบถาม</div>
                    <div class="link-display" onclick="copyTeacherLink(this.querySelector('.copy-btn'))" style="cursor:pointer;" title="คลิกเพื่อคัดลอกลิงก์">
                        <span class="flex-1 select-all" id="surveyLinkText">${fullUrl}</span>
                        <button class="copy-btn" onclick="event.stopPropagation(); copyTeacherLink(this)">📋 คัดลอก</button>
                    </div>
                </div>
                <div class="qr-code-section">
                    <div class="qr-link-label">📱 QR Code สำหรับตอบแบบสอบถาม</div>
                    <div class="qr-code-wrapper" id="qrCodeWrapper">
                        <div id="qrCodeContainer"></div>
                    </div>
                    <p class="qr-survey-title" id="qrSurveyTitle">${escapeHtml(surveyTitle)}</p>
                    <div class="qr-actions">
                        <button class="btn btn-primary btn-sm" onclick="teacherDownloadQR()">📥 ดาวน์โหลด QR</button>
                        <button class="btn btn-secondary btn-sm" onclick="teacherPrintQR()">🖨️ พิมพ์ QR</button>
                    </div>
                </div>
                <p class="mt-16 text-sm text-muted" style="text-align:center;">⚡ แบบสอบถามถูกเปิดใช้งานอัตโนมัติเมื่อสร้างลิงก์</p>
            </div>
        `;
        Modal.create('🔗 ลิงก์และ QR Code', html, '', 'modal-lg');

        // Generate QR Code using QRCodeJS
        setTimeout(() => {
            const container = document.getElementById('qrCodeContainer');
            if (container && typeof QRCode !== 'undefined') {
                new QRCode(container, {
                    text: fullUrl,
                    width: 280,
                    height: 280,
                    colorDark: '#1e3a8a',
                    colorLight: '#ffffff',
                    correctLevel: QRCode.CorrectLevel.H
                });
            }
        }, 100);
    } catch (err) {
        Toast.error(err.message);
    }
}

function copyTeacherLink(btnEl) {
    const text = document.getElementById('surveyLinkText')?.textContent?.trim();
    if (text) {
        const btn = btnEl || document.querySelector('.link-display .copy-btn');
        copyTextToClipboard(text, btn);
    }
}

function getTeacherQRImage() {
    const container = document.getElementById('qrCodeContainer');
    if (!container) return null;
    return container.querySelector('canvas') || container.querySelector('img');
}

function teacherDownloadQR() {
    const qrEl = getTeacherQRImage();
    const title = document.getElementById('qrSurveyTitle')?.textContent || 'survey';
    if (!qrEl) return;

    let qrDataUrl;
    if (qrEl.tagName === 'CANVAS') {
        qrDataUrl = qrEl.toDataURL('image/png');
    } else {
        qrDataUrl = qrEl.src;
    }

    const exportCanvas = document.createElement('canvas');
    const qrSize = 280;
    const padding = 40;
    const titleHeight = 60;
    const footerHeight = 40;
    exportCanvas.width = qrSize + padding * 2;
    exportCanvas.height = qrSize + padding * 2 + titleHeight + footerHeight;

    const ctx = exportCanvas.getContext('2d');
    ctx.fillStyle = '#ffffff';
    ctx.fillRect(0, 0, exportCanvas.width, exportCanvas.height);

    ctx.fillStyle = '#1a1a2e';
    ctx.font = 'bold 16px sans-serif';
    ctx.textAlign = 'center';
    const maxTitleWidth = exportCanvas.width - 40;
    let displayTitle = title;
    if (ctx.measureText(displayTitle).width > maxTitleWidth) {
        while (ctx.measureText(displayTitle + '...').width > maxTitleWidth && displayTitle.length > 0) {
            displayTitle = displayTitle.slice(0, -1);
        }
        displayTitle += '...';
    }
    ctx.fillText(displayTitle, exportCanvas.width / 2, padding + 20);

    const img = new Image();
    img.onload = function() {
        ctx.drawImage(img, padding, padding + titleHeight, qrSize, qrSize);
        ctx.fillStyle = '#6b7280';
        ctx.font = '12px sans-serif';
        ctx.fillText('สแกนเพื่อตอบแบบสอบถาม — TPU Survey', exportCanvas.width / 2, exportCanvas.height - 16);

        const link = document.createElement('a');
        const safeName = title.replace(/[^a-zA-Z0-9ก-๙]/g, '_').substring(0, 50);
        link.download = `QR_${safeName}.png`;
        link.href = exportCanvas.toDataURL('image/png');
        link.click();
        Toast.success('ดาวน์โหลด QR Code สำเร็จ');
    };
    img.src = qrDataUrl;
}

function teacherPrintQR() {
    const qrEl = getTeacherQRImage();
    const title = document.getElementById('qrSurveyTitle')?.textContent || 'แบบสอบถาม';
    const linkText = document.getElementById('surveyLinkText')?.textContent || '';
    if (!qrEl) return;

    let qrDataUrl;
    if (qrEl.tagName === 'CANVAS') {
        qrDataUrl = qrEl.toDataURL('image/png');
    } else {
        qrDataUrl = qrEl.src;
    }

    const printWindow = window.open('', '_blank');
    printWindow.document.write(`
        <!DOCTYPE html><html><head><title>พิมพ์ QR Code</title>
        <style>
            body { font-family: 'Sarabun', sans-serif; text-align: center; padding: 40px; }
            h2 { color: #1a1a2e; margin-bottom: 8px; }
            .subtitle { color: #6b7280; font-size: 14px; margin-bottom: 24px; }
            img { border: 2px solid #e5e7eb; border-radius: 12px; padding: 8px; }
            .link { color: #6b7280; font-size: 11px; word-break: break-all; margin-top: 16px; }
            .footer { margin-top: 32px; color: #9ca3af; font-size: 12px; }
        </style></head>
        <body>
            <h2>${title}</h2>
            <p class="subtitle">สแกน QR Code เพื่อตอบแบบสอบถาม</p>
            <img src="${qrDataUrl}" width="300" height="300">
            <p class="link">${linkText}</p>
            <p class="footer">TPU Survey — มหาวิทยาลัยตาปี</p>
            <script>window.onload = function() { window.print(); }<\/script>
        </body></html>
    `);
    printWindow.document.close();
}

function teacherViewStats(surveyId) {
    window.open(`stats.html?survey_id=${surveyId}`, '_blank');
}

// ============================================================
// Profile Management
// ============================================================
async function loadProfile() {
    try {
        const data = await API.get('profile.php?action=get');
        const u = data.user;

        // Fill the form
        document.getElementById('profileCode').value = u.personnel_code || u.username || '-';
        document.getElementById('profileName').value = u.full_name || '';
        document.getElementById('profileEmail').value = u.email || '';
        document.getElementById('profileSubject').value = u.subject_area || '';
        document.getElementById('profileBranch').value = u.branch_code || '';
        document.getElementById('profilePassword').value = '';
        document.getElementById('profilePasswordConfirm').value = '';

        // Fill the sidebar card
        document.getElementById('profileDisplayName').textContent = u.full_name || '-';
        document.getElementById('profileDisplayRole').textContent = u.role === 'admin' ? 'ผู้ดูแลระบบ' : 'อาจารย์ / เจ้าของโครงการ';
        document.getElementById('profileAvatar').textContent = (u.full_name || 'T').charAt(0).toUpperCase();
        document.getElementById('profilePersonnelCode').textContent = u.personnel_code || u.username || '-';

        const badge = document.getElementById('profileBadge');
        if (badge) {
            badge.textContent = u.role === 'admin' ? '👑 ผู้ดูแลระบบ' : '🎓 อาจารย์';
            badge.className = `user-card-badge ${u.role}`;
        }
    } catch (err) {
        Toast.error(err.message);
    }
}

async function saveProfile() {
    const fullName = document.getElementById('profileName').value.trim();
    const email = document.getElementById('profileEmail').value.trim();
    const subjectArea = document.getElementById('profileSubject').value.trim();
    const branchCode = document.getElementById('profileBranch').value.trim();
    const password = document.getElementById('profilePassword').value;
    const passwordConfirm = document.getElementById('profilePasswordConfirm').value;

    if (!fullName) {
        Toast.warning('กรุณากรอกชื่อ-นามสกุล');
        return;
    }

    if (password && password.length < 4) {
        Toast.warning('รหัสผ่านต้องมีอย่างน้อย 4 ตัวอักษร');
        return;
    }

    if (password && password !== passwordConfirm) {
        Toast.warning('รหัสผ่านไม่ตรงกัน');
        return;
    }

    const payload = {
        full_name: fullName,
        email: email,
        subject_area: subjectArea,
        branch_code: branchCode
    };

    if (password) {
        payload.password = password;
    }

    try {
        await API.post('profile.php?action=update', payload);
        Toast.success('บันทึกข้อมูลส่วนตัวสำเร็จ');

        // Update sidebar display
        document.getElementById('userName').textContent = fullName;
        document.getElementById('userAvatar').textContent = fullName.charAt(0).toUpperCase();

        // Reload profile card
        loadProfile();
    } catch (err) {
        Toast.error(err.message);
    }
}

// ============================================================
// Google Forms Import Modals & Functions
// ============================================================
function showImportGoogleFormModal() {
    const html = `
        <div style="margin-bottom:16px;">
            <div style="display:flex;gap:12px;margin-bottom:16px;border-bottom:1px solid #e5e7eb;padding-bottom:10px;">
                <button id="tabUrlBtn" type="button" class="btn btn-sm btn-primary" onclick="switchImportTab('url')">🌐 วาง URL / Link</button>
                <button id="tabJsonBtn" type="button" class="btn btn-sm btn-secondary" onclick="switchImportTab('json')">📄 อัปโหลดไฟล์ JSON</button>
            </div>

            <!-- Tab 1: URL -->
            <div id="importTabUrl">
                <div class="form-group">
                    <label class="form-label">Google Form URL / Link *</label>
                    <input type="url" class="form-input" id="googleFormUrl" placeholder="https://docs.google.com/forms/d/e/1FAIpQLS.../viewform">
                    <small class="text-muted mt-8" style="display:block;">วางลิงก์แบบสอบถาม Google Forms ที่เปิดสาธารณะ (Public)</small>
                </div>
            </div>

            <!-- Tab 2: JSON -->
            <div id="importTabJson" style="display:none;">
                <div class="form-group">
                    <label class="form-label">เลือกไฟล์ JSON โครงสร้างฟอร์ม *</label>
                    <input type="file" class="form-input" id="googleFormJsonFile" accept=".json">
                </div>
                <div class="form-group">
                    <label class="form-label">หรือวางข้อมูล JSON ตรงนี้</label>
                    <textarea class="form-input" id="googleFormJsonText" rows="4" placeholder='{"title": "แบบสอบถาม...", "sections": [...]}'></textarea>
                </div>
            </div>
        </div>
    `;
    const footer = `
        <button class="btn btn-secondary" onclick="Modal.hide('importGFormModal');document.getElementById('importGFormModal')?.remove();">ยกเลิก</button>
        <button class="btn btn-primary" id="btnSubmitImportGForm" onclick="submitImportGoogleForm()">📥 นำเข้าแบบสอบถาม</button>
    `;
    const modalId = Modal.create('📥 นำเข้าแบบสอบถามจาก Google Forms', html, footer);
    const modalEl = document.getElementById(modalId);
    if (modalEl) modalEl.id = 'importGFormModal';
}

function switchImportTab(tab) {
    const urlTab = document.getElementById('importTabUrl');
    const jsonTab = document.getElementById('importTabJson');
    const urlBtn = document.getElementById('tabUrlBtn');
    const jsonBtn = document.getElementById('tabJsonBtn');

    if (tab === 'url') {
        if (urlTab) urlTab.style.display = 'block';
        if (jsonTab) jsonTab.style.display = 'none';
        if (urlBtn) urlBtn.className = 'btn btn-sm btn-primary';
        if (jsonBtn) jsonBtn.className = 'btn btn-sm btn-secondary';
    } else {
        if (urlTab) urlTab.style.display = 'none';
        if (jsonTab) jsonTab.style.display = 'block';
        if (urlBtn) urlBtn.className = 'btn btn-sm btn-secondary';
        if (jsonBtn) jsonBtn.className = 'btn btn-sm btn-primary';
    }
}

async function submitImportGoogleForm() {
    const urlTab = document.getElementById('importTabUrl');
    const btn = document.getElementById('btnSubmitImportGForm');

    if (btn) {
        btn.disabled = true;
        btn.textContent = '⏳ กำลังนำเข้าข้อมูล...';
    }

    try {
        if (urlTab && urlTab.style.display !== 'none') {
            const url = document.getElementById('googleFormUrl')?.value?.trim();
            if (!url) {
                Toast.warning('กรุณาระบุ Google Form URL');
                if (btn) { btn.disabled = false; btn.textContent = '📥 นำเข้าแบบสอบถาม'; }
                return;
            }

            const res = await API.post('import_google_form.php?action=importFromUrl', { url });
            Toast.success(res.message || 'นำเข้าแบบสอบถามสำเร็จ!');
            Modal.hide('importGFormModal');
            document.getElementById('importGFormModal')?.remove();
            if (typeof loadSurveys === 'function') loadSurveys();
            if (typeof loadTeacherSurveys === 'function') loadTeacherSurveys();
        } else {
            const fileInput = document.getElementById('googleFormJsonFile');
            const jsonText = document.getElementById('googleFormJsonText')?.value?.trim();

            let surveyData = null;

            if (fileInput && fileInput.files.length > 0) {
                const text = await fileInput.files[0].text();
                surveyData = JSON.parse(text);
            } else if (jsonText) {
                surveyData = JSON.parse(jsonText);
            }

            if (!surveyData) {
                Toast.warning('กรุณาเลือกไฟล์ JSON หรือระบุข้อความ JSON');
                if (btn) { btn.disabled = false; btn.textContent = '📥 นำเข้าแบบสอบถาม'; }
                return;
            }

            const res = await API.post('import_google_form.php?action=importFromJson', { survey_data: surveyData });
            Toast.success(res.message || 'นำเข้าแบบสอบถามสำเร็จ!');
            Modal.hide('importGFormModal');
            document.getElementById('importGFormModal')?.remove();
            if (typeof loadSurveys === 'function') loadSurveys();
            if (typeof loadTeacherSurveys === 'function') loadTeacherSurveys();
        }
    } catch (err) {
        Toast.error(err.message || 'เกิดข้อผิดพลาดในการนำเข้าแบบสอบถาม');
    } finally {
        if (btn) {
            btn.disabled = false;
            btn.textContent = '📥 นำเข้าแบบสอบถาม';
        }
    }
}

function showImportResponsesModal(surveyId, surveyTitle) {
    const html = `
        <form id="importRespForm">
            <input type="hidden" name="survey_id" value="${surveyId}">
            <div class="form-group">
                <label class="form-label">แบบสอบถาม:</label>
                <div style="font-weight:600;font-size:15px;color:var(--navy-600);">${escapeHtml(surveyTitle)}</div>
            </div>
            <div class="form-group">
                <label class="form-label">เลือกไฟล์ CSV ข้อมูลคำตอบจาก Google Forms *</label>
                <input type="file" class="form-input" name="csv_file" accept=".csv" required>
                <small class="text-muted mt-8" style="display:block;">ไฟล์ .csv ที่ Export มาจาก Google Sheets / Google Forms (แถวแรกเป็นชื่อคำถาม)</small>
            </div>
        </form>
    `;
    const footer = `
        <button class="btn btn-secondary" onclick="Modal.hide('importRespModal');document.getElementById('importRespModal')?.remove();">ยกเลิก</button>
        <button class="btn btn-primary" id="btnSubmitImportResp" onclick="submitImportResponses(${surveyId})">📥 นำเข้าคำตอบลงระบบ</button>
    `;
    const modalId = Modal.create('📥 นำเข้าคำตอบจาก Google Forms (CSV)', html, footer);
    const modalEl = document.getElementById(modalId);
    if (modalEl) modalEl.id = 'importRespModal';
}

async function submitImportResponses(surveyId) {
    const form = document.getElementById('importRespForm');
    const fileInput = form?.querySelector('input[name="csv_file"]');
    if (!fileInput || fileInput.files.length === 0) {
        Toast.warning('กรุณาเลือกไฟล์ CSV คำตอบ');
        return;
    }

    const btn = document.getElementById('btnSubmitImportResp');
    if (btn) {
        btn.disabled = true;
        btn.textContent = '⏳ กำลังนำเข้าคำตอบ...';
    }

    const fd = new FormData(form);

    try {
        const res = await API.upload('import_responses.php', fd);
        Toast.success(res.message || 'นำเข้าคำตอบสำเร็จ!');
        Modal.hide('importRespModal');
        document.getElementById('importRespModal')?.remove();
        if (typeof loadSurveys === 'function') loadSurveys();
        if (typeof loadTeacherSurveys === 'function') loadTeacherSurveys();
    } catch (err) {
        Toast.error(err.message || 'เกิดข้อผิดพลาดในการนำเข้าคำตอบ');
    } finally {
        if (btn) {
            btn.disabled = false;
            btn.textContent = '📥 นำเข้าคำตอบลงระบบ';
        }
    }
}

// Global Window bindings
window.showImportGoogleFormModal = showImportGoogleFormModal;
window.switchImportTab = switchImportTab;
window.submitImportGoogleForm = submitImportGoogleForm;
window.showImportResponsesModal = showImportResponsesModal;
window.submitImportResponses = submitImportResponses;

document.addEventListener('DOMContentLoaded', initTeacher);