Init

go.mod

@@ -0,0 +1,3 @@
+module git.fjla.uk/fred.boniface/barcodes
+
+go 1.19

validation/charsets.go

@@ -0,0 +1,11 @@
+package validation
+
+import "regexp"
+
+var (
+	ASCII    = regexp.MustCompile(`^[\x00-\x7F]+$`)
+	ANY      = regexp.MustCompile(`.`)
+	CODE39   = regexp.MustCompile(`^[0-9A-Z\-\.\ $%*+/]+$`)
+	NUMERAL  = regexp.MustCompile(`^[0-9]+$`)
+	ISO88591 = regexp.MustCompile(`^[\x00-\xFF]+$`)
+)

validation/rules.go

@@ -0,0 +1,89 @@
+package validation
+
+import "regexp"
+
+// This needs to be a map of structs
+
+type rule struct {
+	minLength uint64
+	maxLength uint64
+	charset   regexp.Regexp
+	divisible uint8
+}
+
+var aztec = rule{
+	minLength: 1,
+	maxLength: 3067,
+	charset:   *ANY,
+	divisible: 1,
+}
+
+var code39 = rule{
+	minLength: 1,
+	maxLength: 80,
+	charset:   *CODE39,
+	divisible: 1,
+}
+
+var code128 = rule{
+	minLength: 1,
+	maxLength: 80,
+	charset:   *ASCII,
+	divisible: 1,
+}
+
+var datamatrix = rule{
+	minLength: 1,
+	maxLength: 2335,
+	charset:   *ANY,
+	divisible: 1,
+}
+
+var ean8 = rule{
+	minLength: 7,
+	maxLength: 7,
+	charset:   *NUMERAL,
+	divisible: 1,
+}
+
+var ean13 = rule{
+	minLength: 12,
+	maxLength: 12,
+	charset:   *NUMERAL,
+	divisible: 1,
+}
+
+var ean14 = rule{
+	minLength: 2,
+	maxLength: 80,
+	charset:   *NUMERAL,
+	divisible: 2,
+}
+
+var pdf417 = rule{
+	minLength: 1,
+	maxLength: 1100,
+	charset:   *ANY,
+	divisible: 1,
+}
+
+var pzn7 = rule{
+	minLength: 7,
+	maxLength: 7,
+	charset:   *NUMERAL,
+	divisible: 1,
+}
+
+var qr = rule{
+	minLength: 1,
+	maxLength: 4296,
+	charset:   *ISO88591,
+	divisible: 1,
+}
+
+var upca = rule{
+	minLength: 11,
+	maxLength: 11,
+	charset:   *NUMERAL,
+	divisible: 1,
+}

validation/validate.go

@@ -0,0 +1,28 @@
+package validation
+
+import "fmt"
+
+func Validate(input string, format string) bool {
+	rule, exists := barcodeRules[format]
+	if !exists {
+		fmt.Printf("Error: No rule found for format '%s'\n", format)
+		return false
+	}
+
+	if uint64(len(input)) < rule.minLength || uint64(len(input)) > rule.maxLength {
+		fmt.Printf("Validation Error: Length must be between %d and %d\n", rule.minLength, rule.maxLength)
+		return false
+	}
+
+	if !rule.charset.MatchString(input) {
+		fmt.Println("Validation Error: Contains illegal characters")
+		return false
+	}
+
+	if uint64(len(input))%uint64(rule.divisible) != 0 {
+		fmt.Printf("Validation Error: Length must be a multiple of %d", rule.divisible)
+		return false
+	}
+
+	return true
+}