데이터 사용량 기준점 입력 모달 추가

monitor.php

@@ -62,6 +62,21 @@ function db_ensure_data_usage_schema(PDO $pdo): void
         $pdo->exec("ALTER TABLE car_data_usage ADD COLUMN carrier_estimated_bytes INT UNSIGNED NOT NULL DEFAULT 0 AFTER total_bytes");
     }
 
+    $pdo->exec("CREATE TABLE IF NOT EXISTS car_usage_calibrations (
+        id INT UNSIGNED NOT NULL AUTO_INCREMENT,
+        month CHAR(7) NOT NULL,
+        anchor_ts DATETIME NOT NULL,
+        total_bytes BIGINT UNSIGNED NOT NULL,
+        meter_adjusted_bytes BIGINT UNSIGNED NOT NULL,
+        included_bytes BIGINT UNSIGNED NOT NULL DEFAULT 104857600,
+        source VARCHAR(32) NOT NULL DEFAULT 'manual',
+        note VARCHAR(255) NULL,
+        created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+        PRIMARY KEY (id),
+        UNIQUE KEY uniq_month_anchor (month, anchor_ts),
+        KEY idx_month_anchor (month, anchor_ts)
+    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci");
+
     $done = true;
 }
 
@@ -245,8 +260,8 @@ function monthly_data_usage(PDO $pdo): array
         $projectionStart = $monthStart->getTimestamp();
     }
     $measuredSeconds = max(1, $now->getTimestamp() - $projectionStart);
-    $currentBilling = current_billing_usage($monthStart->format('Y-m'));
-    $billingScaleInfo = billing_meter_scale_info($monthStart->format('Y-m'), $currentBilling);
+    $currentBilling = current_billing_usage($monthStart->format('Y-m'), $pdo);
+    $billingScaleInfo = billing_meter_scale_info($monthStart->format('Y-m'), $currentBilling, $pdo);
     $billingScale = $billingScaleInfo['scale'];
     $billingCurrentBytes = (int)round($carrierAdjustedTotalBytes * $billingScale);
     $projectedBytes = (int)round($carrierAdjustedTotalBytes / $measuredSeconds * $monthSeconds);
@@ -523,22 +538,61 @@ function calibrated_usage_range(PDO $pdo, DateTimeInterface $start, DateTimeInte
     ];
 }
 
-function current_billing_usage(string $month): ?array
+function billing_usage_row(array $row): array
 {
+    $totalBytes = (int)($row['total_bytes'] ?? 0);
+    $includedBytes = (int)($row['included_bytes'] ?? DATA_MONTHLY_INCLUDED_BYTES);
+
+    return [
+        'month' => (string)($row['month'] ?? ''),
+        'anchor_ts' => $row['anchor_ts'] ?? null,
+        'total_bytes' => $totalBytes,
+        'total_mb' => round(bytes_to_mb($totalBytes), 6),
+        'meter_adjusted_bytes' => (int)($row['meter_adjusted_bytes'] ?? 0),
+        'included_bytes' => $includedBytes,
+        'included_mb' => round(bytes_to_mb($includedBytes), 6),
+        'coupon_registered_at' => $row['coupon_registered_at'] ?? null,
+        'source' => (string)($row['source'] ?? 'manual'),
+        'note' => $row['note'] ?? null,
+        'created_at' => $row['created_at'] ?? null,
+    ];
+}
+
+function current_billing_usage(string $month, ?PDO $pdo = null): ?array
+{
+    if ($pdo instanceof PDO) {
+        try {
+            $stmt = $pdo->prepare("SELECT month, anchor_ts, total_bytes, meter_adjusted_bytes, included_bytes, source, note, created_at
+                FROM car_usage_calibrations
+                WHERE month = ?
+                ORDER BY anchor_ts DESC, id DESC
+                LIMIT 1");
+            $stmt->execute([$month]);
+            $row = $stmt->fetch(PDO::FETCH_ASSOC);
+            if (is_array($row)) {
+                return billing_usage_row($row);
+            }
+        } catch (Throwable $e) {
+            // 테이블 생성 전이거나 DB 권한 문제가 있으면 아래 상수 기준점을 사용한다.
+        }
+    }
+
     if (!isset(DATA_CURRENT_BILLING_USAGE_BYTES[$month])) {
         return null;
     }
 
     $row = DATA_CURRENT_BILLING_USAGE_BYTES[$month];
-    return [
+    return billing_usage_row([
         'month' => $month,
+        'anchor_ts' => $row['anchor_ts'] ?? null,
         'total_bytes' => (int)($row['total_bytes'] ?? 0),
-        'total_mb' => round(bytes_to_mb((int)($row['total_bytes'] ?? 0)), 6),
         'meter_adjusted_bytes' => (int)($row['meter_adjusted_bytes'] ?? 0),
         'included_bytes' => (int)($row['included_bytes'] ?? DATA_MONTHLY_INCLUDED_BYTES),
-        'included_mb' => round(bytes_to_mb((int)($row['included_bytes'] ?? DATA_MONTHLY_INCLUDED_BYTES)), 6),
         'coupon_registered_at' => $row['coupon_registered_at'] ?? null,
-    ];
+        'source' => 'constant',
+        'note' => '코드 기준점',
+        'created_at' => null,
+    ]);
 }
 
 function billing_meter_scale(?array $currentBilling): float
@@ -555,7 +609,45 @@ function billing_meter_scale(?array $currentBilling): float
     return (int)($currentBilling['total_bytes'] ?? 0) / $meterAdjustedBytes;
 }
 
-function billing_meter_scale_info(string $month, ?array $currentBilling): array
+function previous_billing_usage(string $month, ?PDO $pdo = null): ?array
+{
+    $dbRow = null;
+    if ($pdo instanceof PDO) {
+        try {
+            $stmt = $pdo->prepare("SELECT month, anchor_ts, total_bytes, meter_adjusted_bytes, included_bytes, source, note, created_at
+                FROM car_usage_calibrations
+                WHERE month < ?
+                ORDER BY month DESC, anchor_ts DESC, id DESC
+                LIMIT 1");
+            $stmt->execute([$month]);
+            $row = $stmt->fetch(PDO::FETCH_ASSOC);
+            if (is_array($row)) {
+                $dbRow = billing_usage_row($row);
+            }
+        } catch (Throwable $e) {
+            $dbRow = null;
+        }
+    }
+
+    $constantMonth = null;
+    foreach (DATA_CURRENT_BILLING_USAGE_BYTES as $billingMonth => $row) {
+        if ($billingMonth >= $month || ($row['meter_adjusted_bytes'] ?? 0) <= 0) {
+            continue;
+        }
+        if ($constantMonth === null || $billingMonth > $constantMonth) {
+            $constantMonth = $billingMonth;
+        }
+    }
+    $constantRow = $constantMonth ? current_billing_usage($constantMonth, null) : null;
+
+    if ($dbRow && (!$constantRow || strcmp((string)$dbRow['month'], (string)$constantRow['month']) >= 0)) {
+        return $dbRow;
+    }
+
+    return $constantRow;
+}
+
+function billing_meter_scale_info(string $month, ?array $currentBilling, ?PDO $pdo = null): array
 {
     $currentScale = billing_meter_scale($currentBilling);
     if ($currentBilling && $currentScale > 0) {
@@ -567,24 +659,14 @@ function billing_meter_scale_info(string $month, ?array $currentBilling): array
         ];
     }
 
-    $fallbackMonth = null;
-    $fallbackBilling = null;
-    foreach (DATA_CURRENT_BILLING_USAGE_BYTES as $billingMonth => $row) {
-        if ($billingMonth >= $month || ($row['meter_adjusted_bytes'] ?? 0) <= 0) {
-            continue;
-        }
-        if ($fallbackMonth === null || $billingMonth > $fallbackMonth) {
-            $fallbackMonth = $billingMonth;
-            $fallbackBilling = current_billing_usage($billingMonth);
-        }
-    }
+    $fallbackBilling = previous_billing_usage($month, $pdo);
 
     $fallbackScale = billing_meter_scale($fallbackBilling);
     if ($fallbackBilling && $fallbackScale > 0) {
         return [
             'scale' => $fallbackScale,
             'source' => 'previous_month_anchor',
-            'source_month' => $fallbackMonth,
+            'source_month' => $fallbackBilling['month'] ?? null,
             'source_billing' => $fallbackBilling,
         ];
     }
@@ -625,6 +707,149 @@ function billing_calibration(?array $currentBilling, array $billingScaleInfo): a
     ];
 }
 
+function car_monitor_is_admin(): bool
+{
+    $session = car_monitor_launcher_session();
+    return !empty($session['admin']);
+}
+
+function car_monitor_require_admin(): void
+{
+    if (car_monitor_is_admin()) {
+        return;
+    }
+
+    json_response([
+        'status' => 'forbidden',
+        'message' => '관리자 권한이 필요합니다.',
+    ], 403);
+}
+
+function request_payload(): array
+{
+    $raw = file_get_contents('php://input');
+    if (is_string($raw) && trim($raw) !== '') {
+        $json = json_decode($raw, true);
+        if (is_array($json)) {
+            return $json;
+        }
+    }
+
+    return $_POST;
+}
+
+function parse_usage_bytes(mixed $value, string $unit): int
+{
+    $normalized = trim(str_replace(',', '', (string)$value));
+    if ($normalized === '' || !is_numeric($normalized)) {
+        throw new InvalidArgumentException('T world 사용량을 숫자로 입력해야 합니다.');
+    }
+
+    $amount = (float)$normalized;
+    if ($amount < 0) {
+        throw new InvalidArgumentException('T world 사용량은 0 이상이어야 합니다.');
+    }
+
+    return match (strtolower(trim($unit))) {
+        'b', 'byte', 'bytes' => (int)round($amount),
+        'kb', 'kib' => (int)round($amount * 1024),
+        'mb', 'mib' => (int)round($amount * 1024 * 1024),
+        default => throw new InvalidArgumentException('사용량 단위는 B, KB, MB 중 하나여야 합니다.'),
+    };
+}
+
+function parse_anchor_datetime(?string $value): DateTimeImmutable
+{
+    $timezone = new DateTimeZone(date_default_timezone_get());
+    $raw = trim((string)$value);
+    if ($raw === '') {
+        return new DateTimeImmutable('now', $timezone);
+    }
+
+    $normalized = str_replace('T', ' ', $raw);
+    if (preg_match('/^\d{4}-\d{2}-\d{2} \d{2}:\d{2}$/', $normalized)) {
+        $normalized .= ':00';
+    }
+
+    $dt = DateTimeImmutable::createFromFormat('Y-m-d H:i:s', $normalized, $timezone);
+    if (!$dt) {
+        throw new InvalidArgumentException('기준 시각 형식이 올바르지 않습니다.');
+    }
+
+    return $dt;
+}
+
+function save_usage_calibration(PDO $pdo, array $payload): array
+{
+    $anchor = parse_anchor_datetime($payload['anchor_ts'] ?? null);
+    $monthStart = $anchor->modify('first day of this month')->setTime(0, 0, 0);
+    $nextMonthStart = $monthStart->modify('first day of next month');
+    if ($anchor < $monthStart || $anchor >= $nextMonthStart) {
+        throw new InvalidArgumentException('기준 시각이 현재 월 범위를 벗어났습니다.');
+    }
+
+    $carrierBytes = parse_usage_bytes($payload['total_usage'] ?? '', (string)($payload['unit'] ?? 'KB'));
+    $rangeUsage = calibrated_usage_range($pdo, $monthStart, $anchor);
+    $meterBytes = (int)$rangeUsage['carrier_adjusted_total_bytes'];
+    if ($meterBytes <= 0) {
+        throw new RuntimeException('기준 시각까지의 로컬 통신사형 누적값이 없습니다.');
+    }
+
+    $month = $monthStart->format('Y-m');
+    $anchorText = $anchor->format('Y-m-d H:i:s');
+    $note = trim((string)($payload['note'] ?? ''));
+    if (function_exists('mb_strlen') && mb_strlen($note) > 255) {
+        $note = mb_substr($note, 0, 255);
+    } elseif (strlen($note) > 255) {
+        $note = substr($note, 0, 255);
+    }
+
+    $stmt = $pdo->prepare("INSERT INTO car_usage_calibrations
+        (month, anchor_ts, total_bytes, meter_adjusted_bytes, included_bytes, source, note)
+        VALUES (?, ?, ?, ?, ?, 'manual', ?)
+        ON DUPLICATE KEY UPDATE
+            total_bytes = VALUES(total_bytes),
+            meter_adjusted_bytes = VALUES(meter_adjusted_bytes),
+            included_bytes = VALUES(included_bytes),
+            source = VALUES(source),
+            note = VALUES(note),
+            created_at = CURRENT_TIMESTAMP");
+    $stmt->execute([
+        $month,
+        $anchorText,
+        $carrierBytes,
+        $meterBytes,
+        DATA_MONTHLY_INCLUDED_BYTES,
+        $note === '' ? null : $note,
+    ]);
+
+    return [
+        'month' => $month,
+        'anchor_ts' => $anchorText,
+        'total_bytes' => $carrierBytes,
+        'meter_adjusted_bytes' => $meterBytes,
+        'scale' => round($carrierBytes / $meterBytes, 6),
+        'note' => $note === '' ? null : $note,
+    ];
+}
+
+function usage_calibration_rows(PDO $pdo): array
+{
+    $stmt = $pdo->query("SELECT month, anchor_ts, total_bytes, meter_adjusted_bytes, included_bytes, source, note, created_at
+        FROM car_usage_calibrations
+        ORDER BY month DESC, anchor_ts DESC, id DESC
+        LIMIT 12");
+    $rows = [];
+    foreach ($stmt->fetchAll(PDO::FETCH_ASSOC) as $row) {
+        $billing = billing_usage_row($row);
+        $meter = max(1, (int)$billing['meter_adjusted_bytes']);
+        $billing['scale'] = round((int)$billing['total_bytes'] / $meter, 6);
+        $rows[] = $billing;
+    }
+
+    return $rows;
+}
+
 function json_response(array $payload, int $status = 200): void
 {
     http_response_code($status);
@@ -853,7 +1078,38 @@ if (isset($_GET['mode']) && $_GET['mode'] === 'usage') {
     }
 }
 
+if (isset($_GET['mode']) && $_GET['mode'] === 'usage-calibration') {
+    car_monitor_require_access(true);
+    car_monitor_require_admin();
+
+    try {
+        $pdo = car_db();
+        if ($_SERVER['REQUEST_METHOD'] === 'POST') {
+            $saved = save_usage_calibration($pdo, request_payload());
+            json_response([
+                'status' => 'success',
+                'saved' => $saved,
+                'usage' => monthly_data_usage($pdo),
+                'calibrations' => usage_calibration_rows($pdo),
+            ]);
+        }
+
+        json_response([
+            'status' => 'success',
+            'usage' => monthly_data_usage($pdo),
+            'calibrations' => usage_calibration_rows($pdo),
+            'server_time' => time(),
+        ]);
+    } catch (Throwable $e) {
+        json_response([
+            'status' => 'error',
+            'message' => $e->getMessage(),
+        ], 400);
+    }
+}
+
 car_monitor_require_access(false);
+$carMonitorSession = car_monitor_launcher_session();
 ?>
 <!DOCTYPE html>
 <html lang="ko" data-bs-theme="light">
@@ -1191,6 +1447,132 @@ car_monitor_require_access(false);
             border-color: rgba(34, 197, 94, 0.45);
             color: var(--accent-green);
         }
+        .admin-settings-btn.d-none {
+            display: none !important;
+        }
+        .custom-modal-overlay {
+            position: fixed;
+            inset: 0;
+            z-index: 1080;
+            display: flex;
+            align-items: center;
+            justify-content: center;
+            padding: 18px;
+            background: rgba(15, 23, 42, 0.36);
+            backdrop-filter: blur(8px);
+            -webkit-backdrop-filter: blur(8px);
+        }
+        .custom-modal-overlay[hidden] {
+            display: none !important;
+        }
+        .custom-modal-panel {
+            width: min(560px, 100%);
+            max-height: min(760px, calc(100vh - 36px));
+            overflow: auto;
+            border-radius: 20px;
+            background: var(--card-bg);
+            border: 1px solid var(--card-border);
+            box-shadow: 0 24px 80px rgba(15, 23, 42, 0.28);
+            color: var(--text-primary);
+        }
+        .custom-modal-header,
+        .custom-modal-footer {
+            display: flex;
+            align-items: center;
+            justify-content: space-between;
+            gap: 12px;
+            padding: 18px 20px;
+        }
+        .custom-modal-header {
+            border-bottom: 1px solid var(--card-border);
+        }
+        .custom-modal-footer {
+            border-top: 1px solid var(--card-border);
+            justify-content: flex-end;
+        }
+        .custom-modal-body {
+            padding: 18px 20px 20px;
+        }
+        .calibration-grid {
+            display: grid;
+            grid-template-columns: 1fr 120px;
+            gap: 12px;
+        }
+        .calibration-field {
+            display: flex;
+            flex-direction: column;
+            gap: 6px;
+            margin-bottom: 14px;
+        }
+        .calibration-field label {
+            font-size: 0.78rem;
+            font-weight: 700;
+            color: var(--text-secondary);
+        }
+        .calibration-field input,
+        .calibration-field select {
+            width: 100%;
+            border: 1px solid var(--card-border);
+            border-radius: 12px;
+            background: rgba(255, 255, 255, 0.78);
+            color: #0f172a;
+            padding: 10px 12px;
+            font: inherit;
+            outline: none;
+        }
+        [data-bs-theme="dark"] .calibration-field input,
+        [data-bs-theme="dark"] .calibration-field select {
+            background: rgba(15, 23, 42, 0.86);
+            color: var(--text-primary);
+        }
+        .calibration-summary {
+            display: grid;
+            grid-template-columns: repeat(2, minmax(0, 1fr));
+            gap: 8px;
+            margin: 14px 0;
+        }
+        .calibration-summary-item {
+            border-radius: 12px;
+            background: rgba(148, 163, 184, 0.12);
+            padding: 10px 12px;
+        }
+        .calibration-history {
+            margin-top: 14px;
+            border-radius: 12px;
+            overflow: hidden;
+            border: 1px solid var(--card-border);
+        }
+        .calibration-history-row {
+            display: grid;
+            grid-template-columns: 92px 1fr 78px;
+            gap: 8px;
+            padding: 9px 10px;
+            font-size: 0.78rem;
+            border-bottom: 1px solid var(--card-border);
+        }
+        .calibration-history-row:last-child {
+            border-bottom: 0;
+        }
+        .calibration-message {
+            min-height: 22px;
+            font-size: 0.82rem;
+        }
+        @media (max-width: 575px) {
+            .custom-modal-overlay {
+                align-items: stretch;
+                padding: 10px;
+            }
+            .custom-modal-panel {
+                max-height: calc(100vh - 20px);
+            }
+            .calibration-grid,
+            .calibration-summary {
+                grid-template-columns: 1fr;
+            }
+            .calibration-history-row {
+                grid-template-columns: 1fr;
+            }
+        }
 
         @keyframes pulse-ring {
             0% { box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.7); }
@@ -1449,6 +1831,9 @@ car_monitor_require_access(false);
             <button class="btn-icon-toggle shadow-sm" id="theme-btn" onclick="toggleTheme()">
                 <i class="fas fa-moon"></i>
             </button>
+            <button class="btn-icon-toggle shadow-sm admin-settings-btn d-none" id="settings-btn" type="button" title="설정">
+                <i class="fas fa-gear"></i>
+            </button>
         </div>
     </div>
 
@@ -1859,6 +2244,7 @@ car_monitor_require_access(false);
 
     let currentLang = 'ko';
     const DEFAULT_USAGE_REFRESH_INTERVAL_SEC = 10;
+    const CAR_MONITOR_SESSION = <?php echo json_encode($carMonitorSession, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES); ?>;
 
     const CMD_MAP = {
         se: { label: 'cmdStatus', icon: 'fa-search', bg: 'var(--box-bg-blue)', color: 'var(--accent-blue)' },
@@ -1880,6 +2266,9 @@ car_monitor_require_access(false);
     let wakeLockWanted = false;
     let latestDashboardData = null;
     let latestDashboardMeta = null;
+    let latestUsageData = null;
+    let calibrationModalOpen = false;
+    let calibrationSaveInFlight = false;
     const FALLBACK_BACK_TARGET = 'https://chaegeon.com/';
     const BACK_LINK_PATH_TITLE = {
         '/': '채건닷컴',
@@ -1892,6 +2281,7 @@ car_monitor_require_access(false);
         initLanguage();
         initTheme();
         initWakeLock();
+        initCalibrationSettings();
         initChart();
         fetchData();
         refreshTimer = setInterval(fetchData, 1000);
@@ -2299,6 +2689,7 @@ car_monitor_require_access(false);
 
     function updateUsage(usage) {
         if (!usage) return;
+        latestUsageData = usage;
 
         const total = Number(usage.total_bytes || 0);
         const billingTotal = Number(usage.billing_estimated_current_bytes ?? total);
@@ -2328,6 +2719,191 @@ car_monitor_require_access(false);
 
         fill.style.width = percent.toFixed(2) + '%';
         fill.classList.toggle('warning', overBytes > 0 || projectedOverBytes > 0 || percent >= 85);
+        if (calibrationModalOpen) {
+            renderCalibrationSummary(usage);
+        }
+    }
+
+    function initCalibrationSettings() {
+        const btn = document.getElementById('settings-btn');
+        if (!btn || !CAR_MONITOR_SESSION?.admin) return;
+
+        btn.classList.remove('d-none');
+        btn.addEventListener('click', openCalibrationModal);
+
+        document.getElementById('calibration-close-btn')?.addEventListener('click', closeCalibrationModal);
+        document.getElementById('calibration-cancel-btn')?.addEventListener('click', closeCalibrationModal);
+        document.getElementById('calibration-save-btn')?.addEventListener('click', saveCalibration);
+        ['calibration-total-usage', 'calibration-unit'].forEach(id => {
+            document.getElementById(id)?.addEventListener('input', updateCalibrationPreview);
+            document.getElementById(id)?.addEventListener('change', updateCalibrationPreview);
+        });
+    }
+
+    function openCalibrationModal() {
+        const overlay = document.getElementById('calibration-overlay');
+        if (!overlay) return;
+
+        calibrationModalOpen = true;
+        overlay.hidden = false;
+        document.body.style.overflow = 'hidden';
+        const anchorInput = document.getElementById('calibration-anchor-ts');
+        if (anchorInput && !anchorInput.value) {
+            anchorInput.value = formatDateTimeLocal(new Date());
+        }
+        setCalibrationMessage('T world 사용량을 입력하면 현재 월 기준점으로 저장합니다.', 'muted');
+        renderCalibrationSummary(latestUsageData);
+        fetchCalibrationState();
+        setTimeout(() => document.getElementById('calibration-total-usage')?.focus(), 80);
+    }
+
+    function closeCalibrationModal() {
+        const overlay = document.getElementById('calibration-overlay');
+        if (!overlay) return;
+
+        calibrationModalOpen = false;
+        overlay.hidden = true;
+        document.body.style.overflow = '';
+    }
+
+    function fetchCalibrationState() {
+        fetch('?mode=usage-calibration', { cache: 'no-store' })
+            .then(res => res.json())
+            .then(payload => {
+                if (payload.status !== 'success') {
+                    setCalibrationMessage(payload.message || '기준점 조회 실패', 'danger');
+                    return;
+                }
+                if (payload.usage) {
+                    latestUsageData = payload.usage;
+                    updateUsage(payload.usage);
+                }
+                renderCalibrationHistory(payload.calibrations || []);
+            })
+            .catch(() => setCalibrationMessage('기준점 조회 실패', 'danger'));
+    }
+
+    function saveCalibration() {
+        if (calibrationSaveInFlight) return;
+
+        const totalInput = document.getElementById('calibration-total-usage');
+        const unitInput = document.getElementById('calibration-unit');
+        const anchorInput = document.getElementById('calibration-anchor-ts');
+        const noteInput = document.getElementById('calibration-note');
+        const totalUsage = totalInput?.value?.trim() || '';
+        if (!totalUsage) {
+            setCalibrationMessage('T world 사용량을 입력하세요.', 'danger');
+            totalInput?.focus();
+            return;
+        }
+
+        calibrationSaveInFlight = true;
+        const saveBtn = document.getElementById('calibration-save-btn');
+        if (saveBtn) saveBtn.disabled = true;
+        setCalibrationMessage('저장 중입니다.', 'muted');
+
+        fetch('?mode=usage-calibration', {
+            method: 'POST',
+            cache: 'no-store',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({
+                total_usage: totalUsage,
+                unit: unitInput?.value || 'KB',
+                anchor_ts: anchorInput?.value || '',
+                note: noteInput?.value || '',
+            }),
+        })
+            .then(res => res.json())
+            .then(payload => {
+                if (payload.status !== 'success') {
+                    setCalibrationMessage(payload.message || '저장 실패', 'danger');
+                    return;
+                }
+                if (payload.usage) {
+                    latestUsageData = payload.usage;
+                    updateUsage(payload.usage);
+                }
+                renderCalibrationHistory(payload.calibrations || []);
+                const saved = payload.saved || {};
+                setCalibrationMessage(`저장 완료: ${saved.month || '-'} 배율 ${Number(saved.scale || 0).toFixed(6)}`, 'success');
+                fetchUsage();
+            })
+            .catch(() => setCalibrationMessage('저장 실패', 'danger'))
+            .finally(() => {
+                calibrationSaveInFlight = false;
+                if (saveBtn) saveBtn.disabled = false;
+            });
+    }
+
+    function renderCalibrationSummary(usage) {
+        const setText = (id, value) => {
+            const el = document.getElementById(id);
+            if (el) el.textContent = value;
+        };
+        if (!usage) {
+            setText('calibration-month', '-');
+            setText('calibration-meter', '-');
+            setText('calibration-current-scale', '-');
+            setText('calibration-source', '-');
+            updateCalibrationPreview();
+            return;
+        }
+
+        setText('calibration-month', usage.month || '-');
+        setText('calibration-meter', formatPreciseMb(Number(usage.carrier_adjusted_total_bytes || 0)));
+        setText('calibration-current-scale', Number(usage.billing_meter_scale || 1).toFixed(6));
+        const sourceMonth = usage.billing_meter_scale_source_month || '-';
+        const source = usage.billing_meter_scale_source === 'current_month_anchor'
+            ? '현재월'
+            : (usage.billing_meter_scale_source === 'previous_month_anchor' ? '직전월' : '로컬');
+        setText('calibration-source', `${source} ${sourceMonth}`);
+        updateCalibrationPreview();
+    }
+
+    function renderCalibrationHistory(rows) {
+        const box = document.getElementById('calibration-history');
+        if (!box) return;
+        if (!rows.length) {
+            box.innerHTML = '<div class="calibration-history-row text-muted"><span>저장된 기준점 없음</span></div>';
+            return;
+        }
+
+        box.innerHTML = rows.map(row => {
+            const scale = Number(row.scale || 0);
+            return `
+                <div class="calibration-history-row">
+                    <span class="font-mono">${escapeHtml(row.month || '-')}</span>
+                    <span>${escapeHtml(String(row.anchor_ts || '-').replace(' ', ' '))}<br><span class="text-muted">${formatPreciseMb(Number(row.total_bytes || 0))} / ${formatPreciseMb(Number(row.meter_adjusted_bytes || 0))}</span></span>
+                    <span class="font-mono text-end">${scale ? scale.toFixed(6) : '-'}</span>
+                </div>`;
+        }).join('');
+    }
+
+    function updateCalibrationPreview() {
+        const amount = parseFloat(String(document.getElementById('calibration-total-usage')?.value || '').replace(/,/g, ''));
+        const unit = document.getElementById('calibration-unit')?.value || 'KB';
+        const meterBytes = Number(latestUsageData?.carrier_adjusted_total_bytes || 0);
+        let bytes = 0;
+        if (Number.isFinite(amount) && amount >= 0) {
+            if (unit === 'MB') bytes = amount * 1024 * 1024;
+            else if (unit === 'KB') bytes = amount * 1024;
+            else bytes = amount;
+        }
+        const preview = bytes > 0 && meterBytes > 0 ? bytes / meterBytes : 0;
+        const el = document.getElementById('calibration-preview-scale');
+        if (el) el.textContent = preview ? preview.toFixed(6) : '-';
+    }
+
+    function setCalibrationMessage(message, type = 'muted') {
+        const el = document.getElementById('calibration-message');
+        if (!el) return;
+        el.textContent = message;
+        el.className = `calibration-message text-${type}`;
+    }
+
+    function formatDateTimeLocal(date) {
+        const pad = value => String(value).padStart(2, '0');
+        return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())}T${pad(date.getHours())}:${pad(date.getMinutes())}:${pad(date.getSeconds())}`;
     }
 
     function updateRemote(data) {
@@ -2582,6 +3158,72 @@ car_monitor_require_access(false);
     });
 </script>
 
+<div id="calibration-overlay" class="custom-modal-overlay" hidden>
+  <div class="custom-modal-panel" role="dialog" aria-modal="true" aria-labelledby="calibration-title">
+    <div class="custom-modal-header">
+      <div>
+        <div id="calibration-title" class="fw-bold">데이터 사용량 기준점</div>
+        <div class="small text-muted">T world 사용량 숫자로 월별 보정 배율을 저장합니다.</div>
+      </div>
+      <button type="button" class="btn-icon-toggle" id="calibration-close-btn" title="닫기">
+        <i class="fas fa-xmark"></i>
+      </button>
+    </div>
+    <div class="custom-modal-body">
+      <div class="calibration-grid">
+        <div class="calibration-field">
+          <label for="calibration-total-usage">T world 사용량</label>
+          <input id="calibration-total-usage" name="calibration_total_usage" type="number" inputmode="decimal" min="0" step="0.001" placeholder="예: 6396 또는 6.25" autocomplete="off">
+        </div>
+        <div class="calibration-field">
+          <label for="calibration-unit">단위</label>
+          <select id="calibration-unit" name="calibration_unit">
+            <option value="KB" selected>KB</option>
+            <option value="MB">MB</option>
+            <option value="B">B</option>
+          </select>
+        </div>
+      </div>
+      <div class="calibration-field">
+        <label for="calibration-anchor-ts">기준 시각</label>
+        <input id="calibration-anchor-ts" name="calibration_anchor_ts" type="datetime-local" step="1" autocomplete="off">
+      </div>
+      <div class="calibration-field">
+        <label for="calibration-note">메모</label>
+        <input id="calibration-note" name="calibration_note" type="text" maxlength="80" placeholder="예: T world 사용량 조회" autocomplete="off">
+      </div>
+      <div class="calibration-summary">
+        <div class="calibration-summary-item">
+          <div class="label-text mb-1">현재 월</div>
+          <div id="calibration-month" class="font-mono fw-bold">-</div>
+        </div>
+        <div class="calibration-summary-item">
+          <div class="label-text mb-1">로컬 통신사형 누적</div>
+          <div id="calibration-meter" class="font-mono fw-bold">-</div>
+        </div>
+        <div class="calibration-summary-item">
+          <div class="label-text mb-1">현재 배율</div>
+          <div id="calibration-current-scale" class="font-mono fw-bold">-</div>
+        </div>
+        <div class="calibration-summary-item">
+          <div class="label-text mb-1">입력 예상 배율</div>
+          <div id="calibration-preview-scale" class="font-mono fw-bold">-</div>
+        </div>
+        <div class="calibration-summary-item">
+          <div class="label-text mb-1">기준 출처</div>
+          <div id="calibration-source" class="font-mono fw-bold">-</div>
+        </div>
+      </div>
+      <div id="calibration-message" class="calibration-message text-muted"></div>
+      <div id="calibration-history" class="calibration-history"></div>
+    </div>
+    <div class="custom-modal-footer">
+      <button type="button" class="btn btn-light rounded-pill px-4" id="calibration-cancel-btn">닫기</button>
+      <button type="button" class="btn btn-primary rounded-pill px-4" id="calibration-save-btn">저장</button>
+    </div>
+  </div>
+</div>
+
 <div class="modal fade" id="rawModal" tabindex="-1" aria-hidden="true">
   <div class="modal-dialog modal-lg modal-dialog-centered modal-dialog-scrollable">
     <div class="modal-content glass-card">