// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package internal contains code that is shared among encoding implementations.
package internal

import (
	"golang.org/x/text/encoding"
	"golang.org/x/text/encoding/internal/identifier"
	"golang.org/x/text/transform"
)

// Encoding is an implementation of the Encoding interface that adds the String
// and ID methods to an existing encoding.
type Encoding struct {
	encoding.Encoding
	Name string
	MIB  identifier.MIB
}

// _ verifies that Encoding implements identifier.Interface.
var _ identifier.Interface = (*Encoding)(nil)

func (e *Encoding) String() string {
	return e.Name
}

func (e *Encoding) ID() (mib identifier.MIB, other string) {
	return e.MIB, ""
}

// SimpleEncoding is an Encoding that combines two Transformers.
type SimpleEncoding struct {
	Decoder transform.Transformer
	Encoder transform.Transformer
}

func (e *SimpleEncoding) NewDecoder() transform.Transformer {
	return e.Decoder
}

func (e *SimpleEncoding) NewEncoder() transform.Transformer {
	return e.Encoder
}

// FuncEncoding is an Encoding that combines two functions returning a new
// Transformer.
type FuncEncoding struct {
	Decoder func() transform.Transformer
	Encoder func() transform.Transformer
}

func (e FuncEncoding) NewDecoder() transform.Transformer {
	return e.Decoder()
}

func (e FuncEncoding) NewEncoder() transform.Transformer {
	return e.Encoder()
}