feat: 完成批量插入的SQL生成功能

mapping.go

@@ -0,0 +1,174 @@
+package td_builder
+
+import (
+	"fmt"
+	"manabox.cn/tdengine-mapper/syncmap"
+	"reflect"
+	"strings"
+)
+
+func NewTdMapping() *TdMapping {
+	return &TdMapping{}
+}
+
+// TableNamer 定义了一个获取表名的方法。
+type TableNamer interface {
+	TableName() string
+}
+
+type TdMapping struct {
+	modelMates syncmap.Map[string, *StructMate]
+}
+
+func (b *TdMapping) scanStruct(data ...any) error {
+	for _, datum := range data {
+		if reflect.TypeOf(datum).Kind() != reflect.Ptr {
+			return fmt.Errorf("需要指针类型：%v", reflect.TypeOf(datum))
+		}
+
+		if mate, err := scan(datum); err != nil {
+			return err
+		} else {
+			b.modelMates.Store(mate.UniqueTypeName, mate)
+		}
+	}
+
+	return nil
+}
+
+// 提取 struct 内的信息
+// @param data 包含 struct 类型的数据
+// @return 返回一个 map[表名][]*TableRowMateria， 如果超级表名为空，则表示普通表
+func (b *TdMapping) extractStructData(data ...any) (map[string][]*TableRowMateria, error) {
+	result := make(map[string][]*TableRowMateria)
+
+	for _, item := range data {
+		tf, vf := getReflectTypeAndValue(item)
+		uniqueTypeName := getUniqueTypeName(tf)
+
+		// 获取表名
+		var tableName string
+		{
+			if vf.CanAddr() {
+				if a, ok := vf.Addr().Interface().(TableNamer); ok {
+					tableName = a.TableName()
+				}
+			}
+
+			if tableName == "" {
+				if a, ok := item.(TableNamer); ok {
+					tableName = a.TableName()
+				}
+			}
+
+			if tableName == "" {
+				return nil, fmt.Errorf("not import TableName() string func for struct type: %s", uniqueTypeName)
+			}
+		}
+
+		mate, ok := b.modelMates.Load(uniqueTypeName)
+		if !ok {
+			return nil, fmt.Errorf("not found struct type: %s", uniqueTypeName)
+		}
+
+		materia := &TableRowMateria{
+			SuperTableName: mate.SuperTableName,
+			TableName:      tableName,
+			TagColumns:     make([]string, 0, len(mate.TaggedFieldNames)),
+			TagValues:      make([]any, 0, len(mate.TaggedFieldNames)),
+			Columns:        make([]string, 0, len(mate.DBAnnotatedNames)),
+			Values:         make([]any, 0, len(mate.DBAnnotatedNames)),
+		}
+
+		for _, name := range mate.DBAnnotatedNames {
+			// db tag 名称 -- 数据库列名
+			dbColumn := mate.FiledDBNameCache[name]
+
+			field := vf.FieldByIndex(mate.FieldIndexCache[name])
+			for field.Kind() == reflect.Ptr {
+				if field.IsNil() {
+					break
+				}
+				field = field.Elem()
+			}
+			// 字段值
+			dbValue := field.Interface()
+
+			materia.Columns = append(materia.Columns, dbColumn)
+			materia.Values = append(materia.Values, dbValue)
+		}
+
+		for _, name := range mate.TaggedFieldNames {
+			// db tag 名称 -- 数据库列名
+			tagColumn := mate.FiledDBNameCache[name]
+			field := vf.FieldByIndex(mate.FieldIndexCache[name])
+			for field.Kind() == reflect.Ptr {
+				if field.IsNil() {
+					break
+				}
+				field = field.Elem()
+			}
+			// 字段值
+			tagValue := field.Interface()
+
+			materia.TagColumns = append(materia.TagColumns, tagColumn)
+			materia.TagValues = append(materia.TagValues, tagValue)
+		}
+
+		// 添加到结果
+		key := materia.TableName
+		result[key] = append(result[key], materia)
+	}
+	return result, nil
+}
+
+func (b *TdMapping) ToInsertSQL(data ...any) (string, error) {
+	// 扫描 struct 类型数据
+	if err := b.scanStruct(data...); err != nil {
+		return "", fmt.Errorf("failed to scan struct: %w", err)
+	}
+
+	// 提取 struct 内的信息
+	tableMap, err := b.extractStructData(data...)
+	if err != nil {
+		return "", fmt.Errorf("failed to extract struct data: %w", err)
+	}
+
+	if len(tableMap) == 0 {
+		return "", fmt.Errorf("no data to insert")
+	}
+
+	// 构建 insert 语句
+	/*
+		INSERT INTO
+		表名1 USING 超级表名1 (tag列名) TAGS(tag值) (列名) VALUES (),()
+		表名2 USING 超级表名2 (tag列名)TAGS(tag值) (列名) VALUES (),()
+	*/
+	var buf strings.Builder
+	buf.WriteString("INSERT INTO \n")
+	for _, materials := range tableMap {
+		if len(materials) == 0 {
+			continue
+		}
+
+		var (
+			rowSql string
+			err    error
+		)
+		if materials[0].SuperTableName == "" {
+			// 表名1 (列名) VALUES (),()
+			rowSql, err = buildInsertStatementForNormalTable(materials...)
+		} else {
+			// 表名1 USING 超级表名1 (tag列名) TAGS(tag值) (列名) VALUES (),()
+			rowSql, err = buildInsertStatementForSuperTable(materials...)
+		}
+		if err != nil {
+			return "", fmt.Errorf("failed to build insert statement: %w", err)
+		}
+
+		buf.WriteString(rowSql)
+		buf.WriteString(" \n")
+	}
+
+	return buf.String(), nil
+}