package encoding
import (
"sort"
"strings"
"golang.org/x/text/encoding"
"golang.org/x/text/encoding/charmap"
"golang.org/x/text/encoding/unicode"
)
type EncodingInfo struct {
Encoding encoding.Encoding // nil = UTF-8 passthrough
DisplayName string
Aliases []string
Description string
}
var encodings = map[string]EncodingInfo{
"utf-8": {nil, "UTF-8", []string{"utf8", "ascii"}, "Unicode, no conversion"},
"utf-16-le": {unicode.UTF16(unicode.LittleEndian, unicode.IgnoreBOM), "UTF-16 LE", []string{"utf16le", "utf-16le"}, "Unicode UTF-16 Little Endian"},
"utf-16-be": {unicode.UTF16(unicode.BigEndian, unicode.IgnoreBOM), "UTF-16 BE", []string{"utf16be", "utf-16be"}, "Unicode UTF-16 Big Endian"},
// Cyrillic
"windows-1251": {charmap.Windows1251, "Windows-1251", []string{"cp1251"}, "Windows Cyrillic"},
"koi8-r": {charmap.KOI8R, "KOI8-R", []string{"koi8r"}, "Russian Cyrillic (Unix/Linux)"},
"koi8-u": {charmap.KOI8U, "KOI8-U", []string{"koi8u"}, "Ukrainian Cyrillic (Unix/Linux)"},
"ibm866": {charmap.CodePage866, "CP866", []string{"cp866", "dos-866"}, "DOS Cyrillic"},
"iso-8859-5": {charmap.ISO8859_5, "ISO-8859-5", []string{"iso88595", "cyrillic"}, "ISO Cyrillic"},
// Western European
"windows-1252": {charmap.Windows1252, "Windows-1252", []string{"cp1252"}, "Windows Western European"},
"iso-8859-1": {charmap.ISO8859_1, "ISO-8859-1", []string{"iso88591", "latin1"}, "Latin-1 Western European"},
"iso-8859-15": {charmap.ISO8859_15, "ISO-8859-15", []string{"iso885915", "latin9"}, "Latin-9 Western European (Euro)"},
// Central European
"windows-1250": {charmap.Windows1250, "Windows-1250", []string{"cp1250"}, "Windows Central European"},
"iso-8859-2": {charmap.ISO8859_2, "ISO-8859-2", []string{"iso88592", "latin2"}, "Latin-2 Central European"},
// Greek
"windows-1253": {charmap.Windows1253, "Windows-1253", []string{"cp1253"}, "Windows Greek"},
"iso-8859-7": {charmap.ISO8859_7, "ISO-8859-7", []string{"iso88597", "greek"}, "ISO Greek"},
// Turkish
"windows-1254": {charmap.Windows1254, "Windows-1254", []string{"cp1254"}, "Windows Turkish"},
"iso-8859-9": {charmap.ISO8859_9, "ISO-8859-9", []string{"iso88599", "latin5"}, "Latin-5 Turkish"},
// Other
"windows-1255": {charmap.Windows1255, "Windows-1255", []string{"cp1255"}, "Windows Hebrew"},
"windows-1256": {charmap.Windows1256, "Windows-1256", []string{"cp1256"}, "Windows Arabic"},
"windows-1257": {charmap.Windows1257, "Windows-1257", []string{"cp1257"}, "Windows Baltic"},
"windows-1258": {charmap.Windows1258, "Windows-1258", []string{"cp1258"}, "Windows Vietnamese"},
"windows-874": {charmap.Windows874, "Windows-874", []string{"cp874", "tis-620"}, "Windows Thai"},
}
// registry maps all names (canonical + aliases) to EncodingInfo for fast lookup.
var registry map[string]*EncodingInfo
func init() {
registry = make(map[string]*EncodingInfo)
for canonical, info := range encodings {
infoCopy := info
registry[canonical] = &infoCopy
for _, alias := range info.Aliases {
registry[alias] = &infoCopy
}
}
}
func Get(name string) (encoding.Encoding, bool) {
info, ok := registry[strings.ToLower(name)]
if !ok {
return nil, false
}
return info.Encoding, true
}
func IsUTF8(name string) bool {
lower := strings.ToLower(name)
return lower == "utf-8" || lower == "utf8" || lower == "ascii"
}
type EncodingListItem struct {
Name string `json:"name"`
DisplayName string `json:"displayName"`
Aliases []string `json:"aliases"`
Description string `json:"description"`
}
func ListEncodings() []EncodingListItem {
var items []EncodingListItem
for canonical, info := range encodings {
items = append(items, EncodingListItem{
Name: canonical,
DisplayName: info.DisplayName,
Aliases: info.Aliases,
Description: info.Description,
})
}
sort.Slice(items, func(i, j int) bool {
return items[i].DisplayName < items[j].DisplayName
})
return items
}
