From 5fd9755f120293d90f352dbd654c40e66fda4500 Mon Sep 17 00:00:00 2001
From: LordMathis <matus@namesny.com>
Date: Sun, 2 Mar 2025 21:54:10 +0100
Subject: [PATCH] Implement scan struct

---
 server/internal/db/struct_query.go | 84 ++++++++++++++++++++++++++----
 1 file changed, 74 insertions(+), 10 deletions(-)

diff --git a/server/internal/db/struct_query.go b/server/internal/db/struct_query.go
index efa6321..3484307 100644
--- a/server/internal/db/struct_query.go
+++ b/server/internal/db/struct_query.go
@@ -1,6 +1,7 @@
 package db
 
 import (
+	"database/sql"
 	"fmt"
 	"reflect"
 	"strings"
@@ -8,11 +9,12 @@ import (
 )
 
 type DBField struct {
-	Name       string
-	Value      any
-	Type       reflect.Type
-	useDefault bool
-	encrypted  bool
+	Name         string
+	Value        any
+	Type         reflect.Type
+	OriginalName string
+	useDefault   bool
+	encrypted    bool
 }
 
 func StructTagsToFields(s any) ([]DBField, error) {
@@ -71,11 +73,12 @@ func StructTagsToFields(s any) ([]DBField, error) {
 		}
 
 		fields = append(fields, DBField{
-			Name:       tag,
-			Value:      v.Field(i).Interface(),
-			Type:       f.Type,
-			useDefault: useDefault,
-			encrypted:  encrypted,
+			Name:         tag,
+			Value:        v.Field(i).Interface(),
+			Type:         f.Type,
+			OriginalName: f.Name,
+			useDefault:   useDefault,
+			encrypted:    encrypted,
 		})
 	}
 	return fields, nil
@@ -172,3 +175,64 @@ func (q *Query) UpdateStruct(s any, table string, where []string, args []any) (*
 
 	return q, nil
 }
+
+func (db *database) ScanStruct(row *sql.Row, dest any) error {
+	// Get the fields of the destination struct
+	fields, err := StructTagsToFields(dest)
+	if err != nil {
+		return fmt.Errorf("failed to extract struct fields: %w", err)
+	}
+
+	// Create a slice of pointers to hold the scan destinations
+	scanDest := make([]interface{}, len(fields))
+	destVal := reflect.ValueOf(dest).Elem()
+
+	var fieldsToDecrypt []string
+	nullStringIndexes := make(map[int]reflect.Value)
+
+	for i, field := range fields {
+		// Find the field in the struct
+		structField := destVal.FieldByName(field.OriginalName)
+		if !structField.IsValid() {
+			return fmt.Errorf("struct field %s not found", field.OriginalName)
+		}
+
+		if field.encrypted {
+			fieldsToDecrypt = append(fieldsToDecrypt, field.OriginalName)
+		}
+
+		if structField.Kind() == reflect.String {
+			nullStringIndexes[i] = structField
+
+			var ns sql.NullString
+			scanDest[i] = &ns
+		} else {
+			scanDest[i] = structField.Addr().Interface()
+		}
+	}
+
+	// Scan the row into the destination pointers
+	if err := row.Scan(scanDest...); err != nil {
+		return err
+	}
+
+	// Set null strings to nil if they are null
+	for i, field := range nullStringIndexes {
+		ns := scanDest[i].(*sql.NullString)
+		if ns.Valid {
+			field.SetString(ns.String)
+		}
+	}
+
+	// Decrypt encrypted fields
+	for _, fieldName := range fieldsToDecrypt {
+		field := destVal.FieldByName(fieldName)
+		decValue, err := db.secretsService.Decrypt(field.Interface().(string))
+		if err != nil {
+			return err
+		}
+		field.SetString(decValue)
+	}
+
+	return nil
+}