refactor: restructure project

internal/database/database.go

@@ -0,0 +1,89 @@
+package database
+
+import (
+	"errors"
+
+	"git.ar21.de/yolokube/country-geo-locations/pkg/geoloc"
+	"github.com/hashicorp/go-memdb"
+)
+
+var (
+	ErrUnknownInterface = errors.New("unknown interface structure")
+	ErrIPNetNotFound    = errors.New("IP net not found")
+)
+
+type Database struct {
+	db *memdb.MemDB
+}
+
+func NewDatabase() (*Database, error) {
+	database, err := memdb.NewMemDB(
+		&memdb.DBSchema{
+			Tables: map[string]*memdb.TableSchema{
+				"ipinfo": {
+					Name: "ipinfo",
+					Indexes: map[string]*memdb.IndexSchema{
+						"id": {
+							Name:    "id",
+							Unique:  true,
+							Indexer: &memdb.UintFieldIndex{Field: "IPNumFrom"},
+						},
+					},
+				},
+			},
+		},
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Database{
+		db: database,
+	}, nil
+}
+
+func (d *Database) Load(ipinfos []geoloc.IPInfo) error {
+	txn := d.db.Txn(true)
+	defer txn.Abort()
+
+	for _, ipinfo := range ipinfos {
+		if err := txn.Insert("ipinfo", ipinfo); err != nil {
+			return err
+		}
+	}
+
+	txn.Commit()
+	return nil
+}
+
+func (d *Database) SearchIPNet(ipnetnum uint) (*geoloc.IPInfo, error) {
+	txn := d.db.Txn(false)
+	defer txn.Abort()
+
+	var (
+		ipinfo geoloc.IPInfo
+		ok     bool
+	)
+	for {
+		raw, err := txn.First("ipinfo", "id", ipnetnum)
+		if err != nil {
+			return nil, err
+		}
+
+		if raw != nil {
+			ipinfo, ok = raw.(geoloc.IPInfo)
+			if !ok {
+				return nil, ErrUnknownInterface
+			}
+			break
+		}
+
+		if ipnetnum == 0 {
+			return nil, ErrIPNetNotFound
+		}
+
+		ipnetnum -= geoloc.CalculationValue
+	}
+
+	return &ipinfo, nil
+}