package sql_mapping

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 (
	defaultKeyColumnName     = "id"
	defaultJoinWith          = "::"
	tagPartSeparator         = ";"
	tagPartKeyValueSeparator = ":"
)

const (
	tagKey             = "sqlmapping"
	tagPartIgnore      = "-"
	tagPartColumn      = "column"
	tagPartKey         = "key"
	tagPartNotUpdate   = "notUpdate"
	tagPartUpdateClear = "updateClear"
	tagPartAes         = "aes"
	tagPartJoinWith    = "joinWith"
	tagPartTrim        = "trim"
	tagPartTrimPrefix  = "trimPrefix"
	tagPartTrimSuffix  = "trimSuffix"
)

type Tag struct {
	Name           string
	IsKey          bool
	CanUpdate      bool
	CanUpdateClear bool
	JoinWith       string
	AESKey         string
	Trim           string
	TrimPrefix     string
	TrimSuffix     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
		}

		if entityFieldValue.Kind() == reflect.Pointer && entityFieldValue.IsNil() {
			if !entityFieldValue.CanSet() {
				return errors.New("无法设置值，请检查是否传递的是非指针结构变量且字段为nil")
			}

			entityFieldValue.Set(reflect.New(entityField.Type.Elem()))
		}

		entityFieldElemValue := reflectutils.PointerValueElem(entityFieldValue)

		tagStr := entityField.Tag.Get(tagKey)

		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) {
	if tagStr == tagPartIgnore {
		return nil, nil
	}

	tag := &Tag{
		Name:           strcase.ToSnake(template.Id(field.Name)),
		IsKey:          false,
		CanUpdate:      true,
		CanUpdateClear: false,
		JoinWith:       defaultJoinWith,
		AESKey:         "",
		Trim:           "",
		TrimPrefix:     "",
		TrimSuffix:     "",
	}

	if tag.Name == defaultKeyColumnName {
		tag.IsKey = true
		tag.CanUpdate = false
	}

	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.Name = tagPartKeyValue[1]
			case tagPartKey:
				tag.IsKey = true
				tag.CanUpdate = false
			case tagPartNotUpdate:
				tag.CanUpdate = false
				tag.CanUpdateClear = false
			case tagPartUpdateClear:
				if !tag.CanUpdate {
					tag.CanUpdateClear = false
				} else {
					tag.CanUpdateClear = true
				}
			case tagPartAes:
				if len(tagPartKeyValue[1]) != 32 {
					return nil, errors.New("AES密钥长度应该为32个字节")
				}

				tag.AESKey = tagPartKeyValue[1]
			case tagPartJoinWith:
				if strutils.IsStringEmpty(tagPartKeyValue[1]) {
					return nil, errors.New(tagPartJoinWith + "没有赋值分隔符")
				}

				tag.JoinWith = tagPartKeyValue[1]
			case tagPartTrim:
				tag.Trim = tagPartKeyValue[1]
			case tagPartTrimPrefix:
				tag.TrimPrefix = tagPartKeyValue[1]
			case tagPartTrimSuffix:
				tag.TrimSuffix = tagPartKeyValue[1]
			default:
				err := errors.New(tagKey + "不支持的tag: " + tagPartKeyValue[0])
				logger.GetInstance().Error(err)
				continue
			}
		}
	}

	return tag, nil
}