package util

import (
	"bytes"
	"strings"
)

// ConvertToEnvVarName converts the given text into a usable env var
// removing any special chars with '_' and transforming text to upper case
func ConvertToEnvVarName(text string) string {
	var buffer bytes.Buffer
	upper := strings.ToUpper(text)
	lastCharValid := false
	for i := 0; i < len(upper); i++ {
		ch := upper[i]
		if (ch >= 'A' && ch <= 'Z') || (ch >= '0' && ch <= '9') {
			buffer.WriteString(string(ch))
			lastCharValid = true
		} else {
			if lastCharValid {
				buffer.WriteString("_")
			}
			lastCharValid = false
		}
	}
	return buffer.String()
}