// Frontend Configuration
// This file handles environment variable configuration for the frontend

// Get environment variables (these would be injected by a build tool like Vite)
// For now, we'll use defaults that can be overridden
const getEnvVar = (name, defaultValue) => {
    // In a real Vite setup, this would be import.meta.env[name]
    // For now, we'll check if there's a global config object or use defaults
    if (typeof window !== 'undefined' && window.APP_CONFIG && window.APP_CONFIG[name]) {
        return window.APP_CONFIG[name];
    }
    return defaultValue;
};

// API Configuration - Dynamic backend detection
const DEFAULT_BACKEND_PORTS = [8000, 8001, 8002, 8003, 8004];
const AUTO_DETECT_BACKEND = getEnvVar('VITE_AUTO_DETECT_BACKEND', 'true') === 'true';

// Function to detect available backend
async function detectBackendUrl() {
    if (!AUTO_DETECT_BACKEND) {
        return getEnvVar('VITE_API_BASE_URL', 'http://localhost:8000');
    }
    
    for (const port of DEFAULT_BACKEND_PORTS) {
        try {
            const testUrl = `http://localhost:${port}`;
            const response = await fetch(`${testUrl}/`, { method: 'GET', timeout: 1000 });
            if (response.ok) {
                console.log(`✅ Detected backend at ${testUrl}`);
                return testUrl;
            }
        } catch (e) {
            // Port not available, try next
        }
    }
    
    // Fallback to default
    console.warn('⚠️  Could not detect backend, using default http://localhost:8000');
    return 'http://localhost:8000';
}

// For now, use the configured values (detection can be added later if needed)
export const API_BASE_URL = getEnvVar('VITE_API_BASE_URL', 'http://localhost:8000');
export const API_BASE_URL_WITH_PREFIX = getEnvVar('VITE_API_BASE_URL_WITH_PREFIX', 'http://localhost:8000/api');

// For file serving (same as API_BASE_URL since files are served from the same server)
export const API_BASE_URL_FOR_FILES = API_BASE_URL;

// Development server configuration
export const DEV_SERVER_PORT = getEnvVar('VITE_DEV_SERVER_PORT', '8001');
export const DEV_SERVER_HOST = getEnvVar('VITE_DEV_SERVER_HOST', '127.0.0.1');

// Export all config as a single object for convenience
export const CONFIG = {
    API_BASE_URL,
    API_BASE_URL_WITH_PREFIX,
    API_BASE_URL_FOR_FILES,
    DEV_SERVER_PORT,
    DEV_SERVER_HOST
};

export default CONFIG;