// Set these as Script Properties in the Apps Script editor
PRIVATE_KEY: "-----BEGIN PRIVATE KEY-----\nYourActualPrivateKeyHere\n-----END PRIVATE KEY-----",
SERVICE_ACCOUNT_EMAIL: "scripting-logger@your-project-id.iam.gserviceaccount.com",
PROJECT_ID: "your-project-id",
CLIENT_ID: "your-client-id"

function setupProperties() {
  const properties = PropertiesService.getScriptProperties();
  
  // Replace with your actual values from the JSON file
  properties.setProperties({
    'PRIVATE_KEY': '-----BEGIN PRIVATE KEY-----\nYour-Private-Key-Here\n-----END PRIVATE KEY-----',
    'SERVICE_ACCOUNT_EMAIL': 'scripting-logger@your-project-id.iam.gserviceaccount.com',
    'PROJECT_ID': 'your-project-id',
    'CLIENT_ID': 'your-client-id'
  });
  
  Logger.log('Properties set successfully');
}

// Configuration constants
const SERVICE_ACCOUNT_EMAIL = PropertiesService.getScriptProperties().getProperty('SERVICE_ACCOUNT_EMAIL');
const PROJECT_ID = PropertiesService.getScriptProperties().getProperty('PROJECT_ID');
const CLIENT_ID = PropertiesService.getScriptProperties().getProperty('CLIENT_ID');
const PRIVATE_KEY = PropertiesService.getScriptProperties().getProperty('PRIVATE_KEY');
const DEBUG_LOGGING = false; // Set to true when debugging

// Validate required properties
if (!SERVICE_ACCOUNT_EMAIL || !PROJECT_ID || !PRIVATE_KEY) {
  throw new Error('Missing required service account properties. Please check your Script Properties.');
}

/**
 * Initialize OAuth2 Service for Google Cloud Logging
 * @return {OAuth2Service} Configured OAuth2 service
 */
function getOAuthService() {
  const service = OAuth2.createService('CloudLogging')
    .setTokenUrl('https://oauth2.googleapis.com/token')
    .setPrivateKey(PRIVATE_KEY)
    .setClientId(CLIENT_ID)
    .setIssuer(SERVICE_ACCOUNT_EMAIL)
    .setPropertyStore(PropertiesService.getScriptProperties())
    .setScope('https://www.googleapis.com/auth/logging.write');
  
  return service;
}

/**
 * Reset OAuth2 service (useful for debugging)
 */
function resetOAuthService() {
  const service = getOAuthService();
  service.reset();
  Logger.log('OAuth service reset');
}

/**
 * Send logs to Google Cloud Logging
 * @param {string} message - Log message
 * @param {string} severity - Log severity (DEFAULT, DEBUG, INFO, NOTICE, WARNING, ERROR, CRITICAL)
 * @param {string} logName - Custom log name (optional)
 * @param {Object} jsonPayload - Structured data (optional)
 */
function sendLog(message, severity = 'INFO', logName = 'apps-script-log', jsonPayload = null) {
  // Validate inputs
  if (!message) {
    throw new Error('Log message is required');
  }
  
  if (!PRIVATE_KEY) {
    throw new Error('PRIVATE_KEY not found in Script Properties');
  }

  // Get OAuth2 service
  const service = getOAuthService();
  if (!service.hasAccess()) {
    throw new Error('OAuth service authentication failed. Check service account configuration.');
  }

  // Construct log entry
  const logEntry = {
    logName: `projects/${PROJECT_ID}/logs/${logName}`,
    resource: {
      type: 'global'
    },
    entries: [{
      severity: severity,
      timestamp: new Date().toISOString(),
      ...(jsonPayload ? { jsonPayload } : { textPayload: message })
    }]
  };

  // API request options
  const options = {
    method: 'POST',
    contentType: 'application/json',
    headers: {
      'Authorization': `Bearer ${service.getAccessToken()}`
    },
    payload: JSON.stringify(logEntry)
  };

  // Send request
  try {
    const response = UrlFetchApp.fetch('https://logging.googleapis.com/v2/entries:write', options);
    
    return {
      success: true,
      response: response.getContentText()
    };
  } catch (error) {
    const errorMessage = `Failed to send log: ${error.toString()}`;
    Logger.log(errorMessage);
    throw new Error(errorMessage);
  }
}

/**
 * Log info message
 */
function logInfo(message, data = null) {
  return sendLog(message, 'INFO', 'apps-script-info', data);
}

/**
 * Log error message
 */
function logError(message, error = null) {
  const errorData = error ? {
    message: message,
    error: error.toString(),
    stack: error.stack
  } : null;
  
  return sendLog(message, 'ERROR', 'apps-script-errors', errorData);
}

/**
 * Log warning message
 */
function logWarning(message, data = null) {
  return sendLog(message, 'WARNING', 'apps-script-warnings', data);
}

/**
 * Log debug message (only when DEBUG_LOGGING is true)
 */
function logDebug(message, data = null) {
  if (DEBUG_LOGGING) {
    return sendLog(message, 'DEBUG', 'apps-script-debug', data);
  }
}

function doPost(e) {
  try {
    logInfo('Function started', { functionName: 'doPost', timestamp: new Date() });
    const data = JSON.parse(e.postData.contents);
    
    validateData(data);
    
    // Process and store data
    const result = logTimeEntry(data);
    
    if (result) {
     logInfo('Updated Spreadsheet Successfully', { result: result });
     // Return with CORS headers for downstream apps
     if (result) {
       return ContentService
       .createTextOutput(JSON.stringify({success: true, id: result}))
       .setMimeType(ContentService.MimeType.JSON)
       .setHeaders({
         'Access-Control-Allow-Origin': '*',
         'Access-Control-Allow-Methods': 'POST',
         'Access-Control-Allow-Headers': 'Content-Type'
       });
    }

    logError('Function doPost failed');
    logDebug('debug data:', data); // Set DEBUG to true and run with that flag on, if you need to inspect the data/payload
    throw new Error("No result from logTimeEntry");
      
  } catch (error) {
    logError('Function doPost failed', error);
    logDebug('debug data:', data); // Set DEBUG to true and run with that flag on, if you need to inspect the data/payload
    // Return with CORS headers for downstream apps
    return ContentService
      .createTextOutput(JSON.stringify({error: "Processing failed"}))
      .setMimeType(ContentService.MimeType.JSON)
      .setHeaders({
        'Access-Control-Allow-Origin': '*',
        'Access-Control-Allow-Methods': 'POST',
        'Access-Control-Allow-Headers': 'Content-Type'
      });
  }
}