koki-develop/gat

package prettier

import (
    "bytes"
    "encoding/xml"
    "io"
    "strings"
)

var (
    XML = Register("XML", NewXMLPrettier())
)

type XMLPrettier struct{}

func NewXMLPrettier() *XMLPrettier {
    return &XMLPrettier{}
}

func (*XMLPrettier) Pretty(input string) (string, error) {
    var b bytes.Buffer
    dec := xml.NewDecoder(strings.NewReader(input))
    enc := xml.NewEncoder(&b)
    enc.Indent("", "  ")

    for {
        token, err := dec.Token()
        if err != nil {
            if err == io.EOF {
                break
            }
            return "", err
        }

        if err := enc.EncodeToken(token); err != nil {
            return "", err
        }

        if declaration, ok := token.(xml.ProcInst); ok && declaration.Target == "xml" {
            if err := enc.Flush(); err != nil {
                return "", err
            }
            if _, err := b.WriteString("\n"); err != nil {
                return "", err
            }
        }
    }

    if err := enc.Flush(); err != nil {
        return "", err
    }

    return b.String(), nil
}