/* ===== Training Management (안전교육 실시 - 관리자) ===== */
let pendingRequests = [];
let completedTrainings = [];
let trainingRequestId = null;

/* Signature canvas state */
let sigCanvas, sigCtx;
let isDrawing = false;
let hasSignature = false;

/* ===== Load approved requests needing training ===== */
async function loadPendingTraining() {
    try {
        const res = await api('/visit-requests/requests?status=approved');
        pendingRequests = res.data || [];
        renderPendingTraining();
    } catch (e) {
        showToast('대기 목록 로드 실패: ' + e.message, 'error');
    }
}

function renderPendingTraining() {
    const tbody = document.getElementById('pendingTrainingBody');
    if (!pendingRequests.length) {
        tbody.innerHTML = '<tr><td colspan="7" class="text-center text-gray-400 py-8">교육 대기 중인 신청이 없습니다</td></tr>';
        return;
    }
    tbody.innerHTML = pendingRequests.map(r => `<tr>
        <td>${escapeHtml(r.visitor_company)}</td>
        <td class="text-center">${r.visitor_count}</td>
        <td>${escapeHtml(r.workplace_name || '-')}</td>
        <td>${formatDate(r.visit_date)}</td>
        <td class="hide-mobile">${r.visit_time ? String(r.visit_time).substring(0, 5) : '-'}</td>
        <td>${escapeHtml(r.purpose_name || '-')}</td>
        <td class="text-right">
            <button onclick="openTrainingModal(${r.request_id})" class="text-blue-600 hover:text-blue-800 text-xs px-2 py-1 border border-blue-200 rounded hover:bg-blue-50">
                <i class="fas fa-chalkboard-teacher mr-1"></i>교육실시
            </button>
        </td>
    </tr>`).join('');
}

/* ===== Load completed training records ===== */
async function loadCompletedTraining() {
    try {
        const res = await api('/visit-requests/training');
        completedTrainings = res.data || [];
        renderCompletedTraining();
    } catch (e) {
        showToast('이력 로드 실패: ' + e.message, 'error');
    }
}

function renderCompletedTraining() {
    const tbody = document.getElementById('completedTrainingBody');
    if (!completedTrainings.length) {
        tbody.innerHTML = '<tr><td colspan="7" class="text-center text-gray-400 py-8">교육 완료 이력이 없습니다</td></tr>';
        return;
    }
    tbody.innerHTML = completedTrainings.map(t => {
        const timeRange = t.training_start_time
            ? String(t.training_start_time).substring(0, 5) + (t.training_end_time ? ' ~ ' + String(t.training_end_time).substring(0, 5) : '')
            : '-';
        return `<tr>
            <td>${formatDate(t.training_date)}</td>
            <td>${escapeHtml(t.visitor_company || '-')}</td>
            <td class="text-center">${t.visitor_count || '-'}</td>
            <td>${timeRange}</td>
            <td class="hide-mobile">${escapeHtml(t.training_topics || '-')}</td>
            <td>${escapeHtml(t.trainer_full_name || t.trainer_name || '-')}</td>
            <td class="text-right">
                ${t.completed_at ? '<span class="badge badge-green">완료</span>' : '<span class="badge badge-amber">진행중</span>'}
            </td>
        </tr>`;
    }).join('');
}

/* ===== Training Modal ===== */
function openTrainingModal(requestId) {
    const r = pendingRequests.find(x => x.request_id === requestId);
    if (!r) return;
    trainingRequestId = requestId;

    document.getElementById('trainingRequestInfo').innerHTML = `
        <div class="grid grid-cols-2 gap-2">
            <div><span class="text-gray-500">업체:</span> <strong>${escapeHtml(r.visitor_company)}</strong></div>
            <div><span class="text-gray-500">인원:</span> <strong>${r.visitor_count}명</strong></div>
            <div><span class="text-gray-500">작업장:</span> <strong>${escapeHtml(r.workplace_name || '-')}</strong></div>
            <div><span class="text-gray-500">방문일:</span> <strong>${formatDate(r.visit_date)}</strong></div>
        </div>
    `;

    // Set defaults
    const today = new Date().toISOString().substring(0, 10);
    const now = new Date().toTimeString().substring(0, 5);
    document.getElementById('trainingDate').value = today;
    document.getElementById('trainingStartTime').value = now;
    document.getElementById('trainingEndTime').value = '';
    document.getElementById('trainingTopics').value = '';

    // Reset signature
    clearSignature();

    document.getElementById('trainingModal').classList.remove('hidden');
}

function closeTrainingModal() {
    document.getElementById('trainingModal').classList.add('hidden');
    trainingRequestId = null;
}

/* ===== Submit Training ===== */
async function submitTraining(e) {
    e.preventDefault();
    if (!trainingRequestId) return;

    const data = {
        request_id: trainingRequestId,
        training_date: document.getElementById('trainingDate').value,
        training_start_time: document.getElementById('trainingStartTime').value,
        training_end_time: document.getElementById('trainingEndTime').value || null,
        training_topics: document.getElementById('trainingTopics').value.trim() || null
    };

    if (!data.training_date) { showToast('교육일을 선택해주세요', 'error'); return; }
    if (!data.training_start_time) { showToast('시작시간을 입력해주세요', 'error'); return; }

    try {
        // 1. Create training record
        const createRes = await api('/visit-requests/training', {
            method: 'POST', body: JSON.stringify(data)
        });
        const trainingId = createRes.data?.training_id || createRes.data?.insertId;

        // 2. Complete with signature if exists
        if (trainingId && hasSignature) {
            const signatureData = sigCanvas.toDataURL('image/png');
            await api('/visit-requests/training/' + trainingId + '/complete', {
                method: 'PUT', body: JSON.stringify({ signature_data: signatureData })
            });
        }

        showToast('안전교육이 완료되었습니다');
        closeTrainingModal();
        await Promise.all([loadPendingTraining(), loadCompletedTraining()]);
    } catch (e) {
        showToast(e.message, 'error');
    }
}

/* ===== Signature Pad ===== */
function initSignaturePad() {
    sigCanvas = document.getElementById('signatureCanvas');
    if (!sigCanvas) return;
    sigCtx = sigCanvas.getContext('2d');

    // Adjust canvas resolution for retina displays
    const rect = sigCanvas.getBoundingClientRect();
    const dpr = window.devicePixelRatio || 1;
    sigCanvas.width = rect.width * dpr;
    sigCanvas.height = rect.height * dpr;
    sigCtx.scale(dpr, dpr);
    sigCtx.lineCap = 'round';
    sigCtx.lineJoin = 'round';
    sigCtx.lineWidth = 2;
    sigCtx.strokeStyle = '#1f2937';

    // Mouse events
    sigCanvas.addEventListener('mousedown', startDraw);
    sigCanvas.addEventListener('mousemove', draw);
    sigCanvas.addEventListener('mouseup', stopDraw);
    sigCanvas.addEventListener('mouseleave', stopDraw);

    // Touch events
    sigCanvas.addEventListener('touchstart', function(e) {
        e.preventDefault();
        const touch = e.touches[0];
        startDraw(touchToMouse(touch));
    });
    sigCanvas.addEventListener('touchmove', function(e) {
        e.preventDefault();
        const touch = e.touches[0];
        draw(touchToMouse(touch));
    });
    sigCanvas.addEventListener('touchend', function(e) {
        e.preventDefault();
        stopDraw();
    });
}

function touchToMouse(touch) {
    const rect = sigCanvas.getBoundingClientRect();
    return { offsetX: touch.clientX - rect.left, offsetY: touch.clientY - rect.top };
}

function startDraw(e) {
    isDrawing = true;
    sigCtx.beginPath();
    sigCtx.moveTo(e.offsetX, e.offsetY);
}

function draw(e) {
    if (!isDrawing) return;
    hasSignature = true;
    sigCtx.lineTo(e.offsetX, e.offsetY);
    sigCtx.stroke();
}

function stopDraw() {
    isDrawing = false;
}

function clearSignature() {
    if (!sigCanvas || !sigCtx) return;
    const rect = sigCanvas.getBoundingClientRect();
    sigCtx.clearRect(0, 0, rect.width, rect.height);
    hasSignature = false;
}

/* ===== Init ===== */
function initTrainingPage() {
    if (!initAuth()) return;

    // Check admin
    const isAdmin = currentUser && ['admin', 'system'].includes(currentUser.role);
    if (!isAdmin) {
        document.querySelector('.flex-1.min-w-0').innerHTML = `
            <div class="bg-white rounded-xl shadow-sm p-10 text-center">
                <i class="fas fa-lock text-4xl text-gray-300 mb-4"></i>
                <p class="text-gray-500">관리자 권한이 필요합니다</p>
            </div>`;
        return;
    }

    document.getElementById('trainingForm').addEventListener('submit', submitTraining);
    initSignaturePad();
    loadPendingTraining();
    loadCompletedTraining();
}