Major refactor to library

pkg/utils/phone.go

@@ -0,0 +1,72 @@
+package utils
+
+import (
+	"fmt"
+	"strings"
+)
+
+// FormatPhoneToJID converts a phone number to WhatsApp JID format
+// If the number already contains @, it returns as-is
+// Otherwise, applies formatting rules:
+// - If starts with 0, assumes no country code and replaces 0 with country code
+// - If starts with +, assumes it already has country code
+// - Otherwise adds country code if not present
+// - Adds @s.whatsapp.net suffix
+func FormatPhoneToJID(phone string, defaultCountryCode string) string {
+	// If already in JID format, return as-is
+	if strings.Contains(phone, "@") {
+		return phone
+	}
+
+	// Remove all non-digit characters
+	cleaned := strings.Map(func(r rune) rune {
+		if r >= '0' && r <= '9' {
+			return r
+		}
+		return -1
+	}, phone)
+
+	// If empty after cleaning, return original
+	if cleaned == "" {
+		return phone
+	}
+
+	// If number starts with 0, it definitely doesn't have a country code
+	// Replace the leading 0 with the country code
+	if strings.HasPrefix(cleaned, "0") && defaultCountryCode != "" {
+		countryCode := strings.TrimPrefix(defaultCountryCode, "+")
+		cleaned = countryCode + strings.TrimLeft(cleaned, "0")
+		return fmt.Sprintf("%s@s.whatsapp.net", cleaned)
+	}
+
+	// Remove all leading zeros
+	cleaned = strings.TrimLeft(cleaned, "0")
+
+	// If original phone started with +, it already has country code
+	if strings.HasPrefix(phone, "+") {
+		return fmt.Sprintf("%s@s.whatsapp.net", cleaned)
+	}
+
+	// Add country code if provided and number doesn't start with it
+	if defaultCountryCode != "" {
+		countryCode := strings.TrimPrefix(defaultCountryCode, "+")
+		if !strings.HasPrefix(cleaned, countryCode) {
+			cleaned = countryCode + cleaned
+		}
+	}
+
+	return fmt.Sprintf("%s@s.whatsapp.net", cleaned)
+}
+
+// IsGroupJID checks if a JID is a group JID
+func IsGroupJID(jid string) bool {
+	return strings.HasSuffix(jid, "@g.us")
+}
+
+// IsValidJID checks if a string is a valid WhatsApp JID
+func IsValidJID(jid string) bool {
+	return strings.Contains(jid, "@") &&
+		(strings.HasSuffix(jid, "@s.whatsapp.net") ||
+			strings.HasSuffix(jid, "@g.us") ||
+			strings.HasSuffix(jid, "@broadcast"))
+}