/*
 * Copyright (c) 2020 Alex aka mailoman <alex@webz.asia>
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *   @author Alex aka mailoman <alex@webz.asia>
 *   @copyright Copyright (c) 2020 Alex aka mailoman <alex@webz.asia>
 *   @since 26.01.2020
 *
 */

package main

import (
	"encoding/json"
	"log"

	"github.com/go-convert/fields"
)

type FromStructBase struct {
	ID     string `conv:"new,update"`
	Field1 string `conv:"new,update"`
}

type fromStruct struct {
	FromStructBase `conv:"new,update"`
	Field2         string `conv:"update"`
}

type toStruct struct {
	ID     string
	Field1 string
	Field2 string
	Field3 string
}

func main() {
	fromDefault := fromStruct{
		FromStructBase{"1", "field 1 value"}, "field 2 value",
	}
	toDefault := toStruct{
		"old val 1", "old field 1 value", "old field 2 value", "old field 3 value",
	}

	log.Print("example 3.1 - new")
	from := fromDefault
	to := toDefault

	fields.Сonvert(from, "new", &to)
	fromB, _ := json.Marshal(from)
	toB, _ := json.Marshal(to)

	log.Printf("from %s => to %s", string(fromB), string(toB))

	log.Print("example 3.2 - update")
	from = fromDefault
	to = toDefault

	fields.Сonvert(from, "update", &to)
	fromB, _ = json.Marshal(from)
	toB, _ = json.Marshal(to)

	log.Printf("from %s => to %s", string(fromB), string(toB))
}