// Initialize persistent storage to cache the last known sync date
let storage = STORAGE();
const TASK_DATE_KEY = 'latest_task_date';

/**
 * Returns today's date as a YYYY-MM-DD string,
 * matching the format stored in Fulcrum Task due_date fields.
 */
function getTodayString() {
  let today = new Date();
  let yyyy = today.getFullYear();
  let mm = String(today.getMonth() + 1).padStart(2, '0');
  let dd = String(today.getDate()).padStart(2, '0');
  return `${yyyy}-${mm}-${dd}`;
}

/**
 * Queries the most recent Task record and checks whether
 * its due date matches today. If not, locks down the form.
 */
function checkSyncStatus() {
  LOADRECORDS({
    // Replace this form_id with the Form ID of your Fulcrum Tasks form
    form_id: 'YOUR-TASKS-FORM-ID-HERE',
    order: [['due_date', 'desc']],
    limit: 1
  }, (err, result) => {

    // 1. Handle permission errors first (e.g. user lacks ITA access)
    if (err) {
      ALERT('Access Denied', 'Please contact your Admin for appropriate permissions to continue.');

      // Store an error flag so validate-record always blocks saving
      storage.setItem(TASK_DATE_KEY, 'permission_error');

      // Hide all fields to lock down the form visually
      DATANAMES().forEach(function(dataName) {
        SETHIDDEN(dataName, true);
      });

      return; // Stop further execution
    }

    // 2. No error — compare the latest Task due date to today
    let taskRecords = result.records;

    if (!taskRecords || taskRecords.length === 0) {
      // No Task records came back (e.g. the device hasn't synced the Task yet,
      // or the Task was deleted). Treat this as "not synced" and lock down the form.
      storage.removeItem(TASK_DATE_KEY);

      ALERT(
        'Sync Required',
        'No sync check-in was found on this device. Please close Fulcrum and sync before continuing.'
      );

      DATANAMES().forEach(function(dataName) {
        SETHIDDEN(dataName, true);
      });

      return;
    }

    if (taskRecords.length > 0) {
      let latestTask = taskRecords[0];

      // Replace 'YOUR-DUE-DATE-FIELD-KEY' with the actual field key
      // for the due_date field in your Tasks form (e.g. '0ed3')
      let taskDate = latestTask?.form_values?.['YOUR-DUE-DATE-FIELD-KEY'];

      // Cache the task date for use in validate-record, but avoid storing undefined
      if (taskDate) {
        storage.setItem(TASK_DATE_KEY, taskDate);
      } else {
        // Clear any previously stored date if we don't have a valid value
        storage.removeItem(TASK_DATE_KEY);
      }

      let todayStr = getTodayString();

      if (taskDate === todayStr) {
        // Device has synced today — allow the user to proceed
        // Ensure all fields are visible again in case they were previously hidden
        DATANAMES().forEach(function(dataName) {
          SETHIDDEN(dataName, false);
        });
        // No alert here — users only see a message when action is required
      } else {
        // Task date doesn't match today — device needs to sync
        let lastSyncDisplay = taskDate ? taskDate : 'unknown';
        ALERT(
          'Sync Required',
          `Please close Fulcrum and sync your device before continuing. ` +
          `Last sync date: ${lastSyncDisplay}. Today: ${todayStr}.`
        );

        // Hide all fields to prevent data entry until synced
        DATANAMES().forEach(function(dataName) {
          SETHIDDEN(dataName, true);
        });
      }
    }
  });
}

// Run the sync check every time a record is opened
ON('load-record', checkSyncStatus);

// Block saving if the cached date doesn't match today
// (handles the case where the app is left open overnight)
ON('validate-record', function(event) {
  let storedDate = storage.getItem(TASK_DATE_KEY);
  let todayStr = getTodayString();

  if (storedDate !== todayStr) {
    INVALID('You must discard edits and sync Fulcrum (or request Admin permissions) prior to continuing.');
  }
});