add domain whois/dns support, refactor codebase

internal/db/access.go

@@ -0,0 +1,28 @@
+package db
+
+import (
+	"net"
+
+	"github.com/oschwald/maxminddb-golang"
+)
+
+// GetCityDB retrieves the city database reader.
+func (g *GeoIPManager) GetCityDB() *maxminddb.Reader {
+	g.mu.RLock()
+	defer g.mu.RUnlock()
+	return g.cityDB
+}
+
+// GetASNDB retrieves the ASN database reader.
+func (g *GeoIPManager) GetASNDB() *maxminddb.Reader {
+	g.mu.RLock()
+	defer g.mu.RUnlock()
+	return g.asnDB
+}
+
+// GetASNPrefixes retrieves the list of IP prefixes for a given ASN.
+func (g *GeoIPManager) GetASNPrefixes(asn uint) []*net.IPNet {
+	g.mu.RLock()
+	defer g.mu.RUnlock()
+	return g.asnPrefixMap[asn]
+}