package rule

import (
	"git.sxidc.com/go-framework/baize/framework/core/infrastructure/logger"
	"git.sxidc.com/go-tools/utils/reflectutils"
	"git.sxidc.com/go-tools/utils/strutils"
	"git.sxidc.com/go-tools/utils/template"
	"github.com/iancoleman/strcase"
	"github.com/pkg/errors"
	"reflect"
	"strings"
)

const (
	TypeString = "string"
	TypeTime   = "time"
	TypeNumber = "number"
	TypeBool   = "bool"
)

func IsSupportedType(typeStr string) bool {
	return typeStr == TypeString || typeStr == TypeTime || typeStr == TypeNumber || typeStr == TypeBool
}

const (
	tagPartSeparator         = ";"
	tagPartKeyValueSeparator = ":"
)

const (
	tagKey        = "rule"
	tagPartColumn = "column"
	tagPartType   = "type"
)

type Tag struct {
	ColumnName string
	Type       string
}

func parseTag(entityElemValue reflect.Value, onParsedFieldTagFunc OnParsedFieldTagFunc) error {
	for i := 0; i < entityElemValue.NumField(); i++ {
		entityField := entityElemValue.Type().Field(i)
		entityFieldValue := entityElemValue.Field(i)

		// 无效值，不进行映射
		if !entityFieldValue.IsValid() {
			continue
		}

		entityFieldElemValue := reflectutils.PointerValueElem(entityFieldValue)

		tagStr, ok := entityField.Tag.Lookup(tagKey)
		if !ok {
			continue
		}

		tag, err := parseFieldTag(entityField, tagStr)
		if err != nil {
			return err
		}

		if tag == nil {
			continue
		}

		// 结构类型的字段，解析结构内部
		if entityFieldElemValue.Kind() == reflect.Struct &&
			!reflectutils.IsValueTime(entityFieldElemValue) {
			err := parseTag(entityFieldElemValue, onParsedFieldTagFunc)
			if err != nil {
				return err
			}

			continue
		}

		err = onParsedFieldTagFunc(entityField.Name, entityFieldElemValue, tag)
		if err != nil {
			return err
		}
	}

	return nil
}

func parseFieldTag(field reflect.StructField, tagStr string) (*Tag, error) {
	fieldType := reflectutils.PointerTypeElem(field.Type)
	fieldKind := reflectutils.GroupTypeKind(fieldType)

	var fieldTypeStr string

	if fieldKind == reflect.Int64 || fieldKind == reflect.Uint64 || fieldKind == reflect.Float64 {
		fieldTypeStr = TypeNumber
	} else if fieldKind == reflect.String {
		fieldTypeStr = TypeString
	} else if fieldKind == reflect.Struct && fieldType.String() == "time.Time" {
		fieldTypeStr = TypeTime
	} else if fieldKind == reflect.Bool {
		fieldTypeStr = TypeBool
	} else {
		return nil, errors.New("type支持的类型包括: string, number, time")
	}

	tag := &Tag{
		ColumnName: strcase.ToSnake(template.Id(field.Name)),
		Type:       fieldTypeStr,
	}

	if strutils.IsStringEmpty(tagStr) {
		return tag, nil
	}

	tagParts := strings.Split(tagStr, tagPartSeparator)
	if tagParts != nil || len(tagParts) != 0 {
		for _, tagPart := range tagParts {
			tagPartKeyValue := strings.SplitN(strings.TrimSpace(tagPart), tagPartKeyValueSeparator, 2)
			if tagPartKeyValue != nil && len(tagPartKeyValue) == 2 && strutils.IsStringNotEmpty(tagPartKeyValue[1]) {
				tagPartKeyValue[1] = strings.Trim(tagPartKeyValue[1], "'")
			}

			if strutils.IsStringEmpty(tagPartKeyValue[0]) {
				continue
			}

			switch tagPartKeyValue[0] {
			case tagPartColumn:
				if strutils.IsStringEmpty(tagPartKeyValue[1]) {
					return nil, errors.New("column没有赋值列名")
				}

				tag.ColumnName = tagPartKeyValue[1]
			case tagPartType:
				if strutils.IsStringEmpty(tagPartKeyValue[1]) {
					return nil, errors.New("type没有赋值字段类型")
				}

				if !IsSupportedType(tagPartKeyValue[1]) {
					return nil, errors.Errorf("类型为%v, type支持的类型包括: string, number, time", tagPartKeyValue[1])
				}

				tag.Type = tagPartKeyValue[1]
			default:
				err := errors.New(tagKey + "不支持的tag: " + tagPartKeyValue[0])
				logger.GetInstance().Error(err)
				continue
			}
		}
	}

	return tag, nil
}