/*
 *  MIT License
 *
 *  Copyright (c) 2020 Nicolas JUHEL
 *
 *  Permission is hereby granted, free of charge, to any person obtaining a copy
 *  of this software and associated documentation files (the "Software"), to deal
 *  in the Software without restriction, including without limitation the rights
 *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *  copies of the Software, and to permit persons to whom the Software is
 *  furnished to do so, subject to the following conditions:
 *
 *  The above copyright notice and this permission notice shall be included in all
 *  copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 *  SOFTWARE.
 *
 */

package mail

import (
	"bytes"
	"encoding/base64"
	"mime/quotedprintable"
	"strings"
)

// base64Encode base64 encodes the provided text with line wrapping
func base64Encode(text []byte) []byte {
	// create buffer
	buf := new(bytes.Buffer)

	// create base64 encoder that linewraps
	encoder := base64.NewEncoder(base64.StdEncoding, &base64LineWrap{writer: buf})

	// write the encoded text to buf
	/* #nosec */
	//nolint #nosec
	_, _ = encoder.Write(text)
	_ = encoder.Close()

	return buf.Bytes()
}

// qpEncode uses the quoted-printable encoding to encode the provided text
func qpEncode(text []byte) []byte {
	// create buffer
	buf := new(bytes.Buffer)

	encoder := quotedprintable.NewWriter(buf)

	/* #nosec */
	//nolint #nosec
	_, _ = encoder.Write(text)
	_ = encoder.Close()

	return buf.Bytes()
}

func encodeHeader(text string, charset string, usedChars int) string {
	// create buffer
	buf := new(bytes.Buffer)

	// encode
	encoder := newEncoder(buf, charset, usedChars)
	/* #nosec */
	//nolint #nosec
	_, _ = encoder.encode([]byte(text))

	return buf.String()
}

func escapeQuotes(s string) string {
	quoteEscaper := strings.NewReplacer("\\", "\\\\", `"`, "\\\"")
	return quoteEscaper.Replace(s)
}