loading, converting and preparing env data

main.go

@@ -42,10 +42,94 @@ type Rectangle struct {
 	endpoint Endpoint
 }
 
+func GetEnvFallback(key string, fallback ...string) (string, error) {
+	// Check for function fallback signature
+	length := len(fallback)
+	if length > 1 {
+		return "", errors.New("Invalid signature: Too many fallback values provided!")
+	}
+
+	// Try to get environment variable
+	value, exists := os.LookupEnv(key)
+	if exists {
+		return value, nil
+	}
+
+	// Try using fallback value instead
+	if length == 1 {
+		return fallback[0], nil
+	} else if length == 0 {
+		// No fallback value provided
+		return "", errors.New("Panic: No fallback value provided!")
+	}
+
+	// Could not get environment variable
+	return "", errors.New("Could not get environment variable: " + key)
+}
+
+func ConvertFallback(input string, fallback ...int) (int, error) {
+	// Check for function fallback signature
+	length := len(fallback)
+	if length > 1 {
+		return 0, errors.New("Invalid signature: Too many fallback values provided!")
+	}
+
+	// Try to convert input to int
+	value, err := strconv.Atoi(input)
+	if err == nil {
+		return value, nil
+	}
+
+	// Try using fallback value instead
+	if length == 1 {
+		return fallback[0], nil
+	} else if length == 0 {
+		// No fallback value provided
+		return 0, errors.New("Panic: No fallback value provided!")
+	}
+
+	// Could not convert input
+	return 0, err
+}
+
+func LoadMatrixData() (string, int, int) {
+	// Remote server info
+	API_SERVER_IP, _ := GetEnvFallback(os.Getenv("API_SERVER_IP"), "localhost")
+	API_SERVER_PORT, _ := GetEnvFallback(os.Getenv("API_SERVER_PORT"), "8080")
+
+	// LED panel info
+	PUBLIC_LED_WIDTH, _ := ConvertFallback(os.Getenv("PUBLIC_LED_WIDTH"), 64)
+	PUBLIC_LED_HEIGHT, _ := ConvertFallback(os.Getenv("PUBLIC_LED_HEIGHT"), 64)
+
+	// Matrix arrangement info
+	PUBLIC_LED_CHAIN, _ := ConvertFallback(os.Getenv("PUBLIC_LED_CHAIN"), 1)
+	PUBLIC_LED_PARALLEL, _ := ConvertFallback(os.Getenv("PUBLIC_LED_PARALLEL"), 1)
+
+	// Prepare remote server url
+	url := fmt.Sprintf("http://%s:%s", API_SERVER_IP, API_SERVER_PORT)
+
+	// Calculate combined resolution
+	width := PUBLIC_LED_WIDTH * PUBLIC_LED_CHAIN
+	height := PUBLIC_LED_HEIGHT * PUBLIC_LED_PARALLEL
+
+	return url, width, height
+}
+
 func main() {
 	// Load .env file if it exists
 	err := godotenv.Load(".env")
 	if err != nil {
 		log.Fatal("Error loading .env file")
 	}
+
+	// Load env server data
+	url, _, _ := LoadMatrixData()
+
+	// Initialize resty client
+	client := resty.New()
+
+	// Initialize custom matrix data
+	col := Color{R: 255, G: 0, B: 255, endpoint: COLOR}
+	rct := Rectangle{X: 0, Y: 0, W: 10, H: 10, endpoint: RECTANGLE}
+	upd := Update{endpoint: UPDATE}
 }