Initial commit

js/env-loader.js

@@ -0,0 +1,87 @@
+// env-loader.js
+// This module is responsible for loading environment variables for the PWA
+
+// Store environment variables in a global object
+window.ENV_CONFIG = {
+  // Default values that will be overridden when config.env.js loads
+  PUBLIC_VAPID_KEY: 'your_public_vapid_key_here',
+  BACKEND_URL: 'https://your-push-server.example.com'
+};
+
+// Function to load environment variables from config.env.js
+async function loadEnvVariables() {
+  try {
+    // Try to fetch the config.env.js file which will be generated at build time or deployment
+    const response = await fetch('/config.env.js');
+    
+    if (!response.ok) {
+      console.warn('Could not load config.env.js file. Using default values.');
+      return;
+    }
+    
+    const configText = await response.text();
+    
+    // Extract the configuration object from the JavaScript file
+    // The file should be in format: window.ENV_CONFIG = { key: "value" };
+    try {
+      // Create a safe way to evaluate the config file
+      const configScript = document.createElement('script');
+      configScript.textContent = configText;
+      document.head.appendChild(configScript);
+      document.head.removeChild(configScript);
+      
+      console.log('Environment variables loaded successfully from config.env.js');
+      
+      // Dispatch an event to notify that environment variables have been loaded
+      window.dispatchEvent(new CustomEvent('env-config-loaded', { 
+        detail: { config: window.ENV_CONFIG } 
+      }));
+    } catch (parseError) {
+      console.error('Error parsing config.env.js:', parseError);
+    }
+  } catch (error) {
+    console.error('Error loading environment variables:', error);
+  }
+}
+
+// Export function to initialize environment variables
+export async function initEnv() {
+  await loadEnvVariables();
+  return window.ENV_CONFIG;
+}
+
+// Start loading environment variables immediately
+initEnv();
+
+// Export access functions for environment variables
+export function getEnv(key, defaultValue = '') {
+  return window.ENV_CONFIG[key] || defaultValue;
+}
+
+// Export a function to wait for environment variables to be loaded
+export function waitForEnv() {
+  return new Promise((resolve) => {
+    // If we already have non-default values, resolve immediately
+    if (window.ENV_CONFIG.BACKEND_URL !== 'https://your-push-server.example.com') {
+      resolve(window.ENV_CONFIG);
+      return;
+    }
+    
+    // Otherwise, wait for the env-config-loaded event
+    window.addEventListener('env-config-loaded', (event) => {
+      resolve(event.detail.config);
+    }, { once: true });
+    
+    // Set a timeout to resolve with current values if loading takes too long
+    setTimeout(() => {
+      console.warn('Environment loading timed out, using current values');
+      resolve(window.ENV_CONFIG);
+    }, 3000);
+  });
+}
+
+export default {
+  initEnv,
+  getEnv,
+  waitForEnv
+};