// Licensed to Elasticsearch B.V. under one or more contributor

// license agreements. See the NOTICE file distributed with

// this work for additional information regarding copyright

// ownership. Elasticsearch B.V. licenses this file to you 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.

package gotype

import (

"reflect"

structform "github.com/elastic/go-structform"

"github.com/elastic/go-structform/visitors"

)

// getReflectFoldMapKeys implements inline fold of a map[string]X type,

// not reporting object start/end events

func getReflectFoldMapKeys(c *foldContext, t reflect.Type) (reFoldFn, error) {

if t.Key().Kind() != reflect.String {

return nil, errMapRequiresStringKey

}

f := getMapInlineByPrimitiveElem(t.Elem())

if f != nil {

return f, nil

}

elemVisitor, err := getReflectFold(c, t.Elem())

if err != nil {

return nil, err

}

return makeMapKeysFold(elemVisitor), nil

}

func makeMapKeysFold(elemVisitor reFoldFn) reFoldFn {

return func(C *foldContext, rv reflect.Value) error {

if rv.IsNil() || !rv.IsValid() {

return nil

}

for _, k := range rv.MapKeys() {

if err := C.OnKey(k.String()); err != nil {

return err

}

if err := elemVisitor(C, rv.MapIndex(k)); err != nil {

return err

}

}

return nil

}

}

// getReflectFoldInlineInterface create an inline folder for an yet unknown type.

// The actual types folder must open/close an object

func getReflectFoldInlineInterface(C *foldContext, t reflect.Type) (reFoldFn, error) {

var (

// cache last used folder

lastType reflect.Type

lastVisitor reFoldFn

)

return embeddObjReFold(C, func(C *foldContext, rv reflect.Value) error {

if rv.Type() != lastType {

elemVisitor, err := getReflectFold(C, rv.Type())

if err != nil {

return err

}

lastVisitor = elemVisitor

lastType = rv.Type()

}

return lastVisitor(C, rv)

}), nil

}

func embeddObjReFold(C *foldContext, objFold reFoldFn) reFoldFn {

var (

ctx = *C

vs = visitors.NewExpectObjVisitor(nil)

)

ctx.visitor = structform.EnsureExtVisitor(vs).(visitor)

return func(C *foldContext, rv reflect.Value) error {

// don't inline missing/empty object

if rv.IsNil() || !rv.IsValid() {

return nil

}

vs.SetActive(C.visitor)

err := objFold(&ctx, rv)

if err == nil && !vs.Done() {

err = errExpectedObjectClose

}

vs.SetActive(nil)

return err

}

}