// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later

package convert

import (
	"fmt"
	"reflect"

	converter "github.com/anchore/go-struct-converter"

	"github.com/spdx/tools-golang/spdx/common"
	"github.com/spdx/tools-golang/spdx/v2/v2_1"
	"github.com/spdx/tools-golang/spdx/v2/v2_2"
	"github.com/spdx/tools-golang/spdx/v2/v2_3"
)

var DocumentChain = converter.NewChain(
	v2_1.Document{},
	v2_2.Document{},
	v2_3.Document{},
)

// Document converts from one document to another document
// For example, converting a document to the latest version could be done like:
//
// sourceDoc := // e.g. a v2_2.Document from somewhere
// var targetDoc spdx.Document // this can be any document version
// err := convert.Document(sourceDoc, &targetDoc) // the target must be passed as a pointer
func Document(from common.AnyDocument, to common.AnyDocument) error {
	if !IsPtr(to) {
		return fmt.Errorf("struct to convert to must be a pointer")
	}
	from = FromPtr(from)
	if reflect.TypeOf(from) == reflect.TypeOf(FromPtr(to)) {
		reflect.ValueOf(to).Elem().Set(reflect.ValueOf(from))
		return nil
	}
	return DocumentChain.Convert(from, to)
}