From 4459013c0a224c55f5f2ac5f19a28f26ff134ba3 Mon Sep 17 00:00:00 2001
From: Lunny Xiao <xiaolunwen@gmail.com>
Date: Fri, 23 Jul 2021 15:41:12 +0800
Subject: [PATCH] refactor conversion

---
 convert.go         | 49 ++++++++++++++++++++++++++++++++++++++++++++++
 dialects/dameng.go | 46 ++++++++++++++++++++++++++++++++++++++++---
 session_get.go     |  3 ---
 3 files changed, 92 insertions(+), 6 deletions(-)
 create mode 100644 convert.go

diff --git a/convert.go b/convert.go
new file mode 100644
index 00000000..371ec2bc
--- /dev/null
+++ b/convert.go
@@ -0,0 +1,49 @@
+// Copyright 2017 The Xorm Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xorm
+
+import (
+	"fmt"
+	"reflect"
+	"strconv"
+)
+
+func asKind(vv reflect.Value, tp reflect.Type) (interface{}, error) {
+	switch tp.Kind() {
+	case reflect.Ptr:
+		return asKind(vv.Elem(), tp.Elem())
+	case reflect.Int64:
+		return vv.Int(), nil
+	case reflect.Int:
+		return int(vv.Int()), nil
+	case reflect.Int32:
+		return int32(vv.Int()), nil
+	case reflect.Int16:
+		return int16(vv.Int()), nil
+	case reflect.Int8:
+		return int8(vv.Int()), nil
+	case reflect.Uint64:
+		return vv.Uint(), nil
+	case reflect.Uint:
+		return uint(vv.Uint()), nil
+	case reflect.Uint32:
+		return uint32(vv.Uint()), nil
+	case reflect.Uint16:
+		return uint16(vv.Uint()), nil
+	case reflect.Uint8:
+		return uint8(vv.Uint()), nil
+	case reflect.String:
+		return vv.String(), nil
+	case reflect.Slice:
+		if tp.Elem().Kind() == reflect.Uint8 {
+			v, err := strconv.ParseInt(string(vv.Interface().([]byte)), 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			return v, nil
+		}
+	}
+	return nil, fmt.Errorf("unsupported primary key type: %v, %v", tp, vv)
+}
diff --git a/dialects/dameng.go b/dialects/dameng.go
index c3f7423f..6ffd7cc1 100644
--- a/dialects/dameng.go
+++ b/dialects/dameng.go
@@ -17,6 +17,7 @@ import (
 
 	"gitee.com/travelliu/dm"
 	"xorm.io/xorm/core"
+	"xorm.io/xorm/internal/convert"
 	"xorm.io/xorm/internal/utils"
 	"xorm.io/xorm/schemas"
 )
@@ -1001,7 +1002,7 @@ type damengDriver struct {
 }
 
 // Features return features
-func (p *damengDriver) Features() *DriverFeatures {
+func (d *damengDriver) Features() *DriverFeatures {
 	return &DriverFeatures{
 		SupportReturnInsertedID: false,
 	}
@@ -1009,7 +1010,7 @@ func (p *damengDriver) Features() *DriverFeatures {
 
 // Parse parse the datasource
 // dm://userName:password@ip:port
-func (p *damengDriver) Parse(driverName, dataSourceName string) (*URI, error) {
+func (d *damengDriver) Parse(driverName, dataSourceName string) (*URI, error) {
 	u, err := url.Parse(dataSourceName)
 	if err != nil {
 		return nil, err
@@ -1031,7 +1032,7 @@ func (p *damengDriver) Parse(driverName, dataSourceName string) (*URI, error) {
 	}, nil
 }
 
-func (g *damengDriver) GenScanResult(colType string) (interface{}, error) {
+func (d *damengDriver) GenScanResult(colType string) (interface{}, error) {
 	switch colType {
 	case "CHAR", "NCHAR", "VARCHAR", "VARCHAR2", "NVARCHAR2", "LONG", "CLOB", "NCLOB":
 		var s sql.NullString
@@ -1050,3 +1051,42 @@ func (g *damengDriver) GenScanResult(colType string) (interface{}, error) {
 		return &r, nil
 	}
 }
+
+func (d *damengDriver) Scan(ctx *ScanContext, rows *core.Rows, types []*sql.ColumnType, vv ...interface{}) error {
+	var scanResults = make([]interface{}, 0, len(types))
+	var replaces = make([]bool, 0, len(types))
+	var err error
+	for i, v := range vv {
+		var replaced bool
+		var scanResult interface{}
+		switch types[i].DatabaseTypeName() {
+		case "CLOB":
+			scanResult = &dmClobScanner{}
+			replaced = true
+		default:
+			scanResult = v
+		}
+
+		scanResults = append(scanResults, scanResult)
+		replaces = append(replaces, replaced)
+	}
+
+	if err = rows.Scan(scanResults...); err != nil {
+		return err
+	}
+
+	for i, replaced := range replaces {
+		if replaced {
+			switch t := scanResults[i].(type) {
+			case *dmClobScanner:
+				if err := convert.Assign(vv[i], t.data, ctx.DBLocation, ctx.UserLocation); err != nil {
+					return err
+				}
+			default:
+				return fmt.Errorf("don't support convert %T to %T", t, vv[i])
+			}
+		}
+	}
+
+	return nil
+}
diff --git a/session_get.go b/session_get.go
index 08172524..22b116a9 100644
--- a/session_get.go
+++ b/session_get.go
@@ -130,9 +130,6 @@ var (
 	valuerTypePlaceHolder driver.Valuer
 	valuerType            = reflect.TypeOf(&valuerTypePlaceHolder).Elem()
 
-	scannerTypePlaceHolder sql.Scanner
-	scannerType            = reflect.TypeOf(&scannerTypePlaceHolder).Elem()
-
 	conversionTypePlaceHolder convert.Conversion
 	conversionType            = reflect.TypeOf(&conversionTypePlaceHolder).Elem()
 )