package utils

import (
	"gorm.io/gorm/clause"
	"nCovTrack-Backend/global"
	"reflect"
	"regexp"
	"time"
)

var colNameReg, _ = regexp.Compile(".*column:(.*);?")
var uniqueKeyReg, _ = regexp.Compile(".*(primaryKey|unique).*")

func getNotZeroFields[T any](model T) []string {
	t := reflect.TypeOf(model)
	v := reflect.ValueOf(model)
	var notZeroFields []string
	for i := 0; i < t.NumField(); i++ {
		if !v.Field(i).IsZero() {
			colName := colNameReg.FindSubmatch([]byte(t.Field(i).Tag.Get("gorm")))
			if len(colName) != 2 {
				panic("Model Tag regex error")
			}
			notZeroFields = append(notZeroFields, string(colName[1]))
		}
	}
	return notZeroFields
}

func Upsert[T any](model *T, forceUpdateFiled ...string) (ok bool) {
	t := reflect.TypeOf(model).Elem()
	v := reflect.ValueOf(model).Elem()
	var uniqueKeyField []clause.Column
	notZeroField := NewSet(forceUpdateFiled...).Add("modify_time")
	for i := 0; i < t.NumField(); i++ {
		gormTag := t.Field(i).Tag.Get("gorm")
		if uniqueKey(gormTag) {
			uniqueKeyField = append(uniqueKeyField, clause.Column{Name: columnName(gormTag)})
			continue
		}
		if !v.Field(i).IsZero() {
			notZeroField.Add(columnName(gormTag))
		} else if t.Field(i).Type.Name() == "Time" {
			v.Field(i).Set(reflect.ValueOf(time.Now()))
		}
	}
	tx := global.Db.Clauses(clause.OnConflict{
		Columns:   uniqueKeyField,
		DoUpdates: clause.AssignmentColumns(notZeroField.ToSlice()),
	}, clause.Returning{}).Create(model)
	if tx.Error != nil {
		return false
	}
	return true
}

func columnName(gormTag string) string {
	colNames := colNameReg.FindSubmatch([]byte(gormTag))
	if len(colNames) != 2 {
		panic("Model tag regex error")
	}
	return string(colNames[1])
}

func uniqueKey(gormTag string) bool {
	return uniqueKeyReg.Match([]byte(gormTag))
}