60 lines
1.8 KiB
Go
60 lines
1.8 KiB
Go
|
// Copyright 2023 The Gitea Authors. All rights reserved.
|
||
|
|
// SPDX-License-Identifier: MIT
|
||
|
|
|
||
|
|
package svg
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bytes"
|
||
|
|
"fmt"
|
||
|
|
"regexp"
|
||
|
|
"sync"
|
||
|
|
)
|
||
|
|
|
||
|
|
type normalizeVarsStruct struct {
|
||
|
|
reXMLDoc,
|
||
|
|
reComment,
|
||
|
|
reAttrXMLNs,
|
||
|
|
reAttrSize,
|
||
|
|
reAttrClassPrefix *regexp.Regexp
|
||
|
|
}
|
||
|
|
|
||
|
|
var (
|
||
|
|
normalizeVars *normalizeVarsStruct
|
||
|
|
normalizeVarsOnce sync.Once
|
||
|
|
)
|
||
|
|
|
||
|
|
// Normalize normalizes the SVG content: set default width/height, remove unnecessary tags/attributes
|
||
|
|
// It's designed to work with valid SVG content. For invalid SVG content, the returned content is not guaranteed.
|
||
|
|
func Normalize(data []byte, size int) []byte {
|
||
|
|
normalizeVarsOnce.Do(func() {
|
||
|
|
normalizeVars = &normalizeVarsStruct{
|
||
|
|
reXMLDoc: regexp.MustCompile(`(?s)<\?xml.*?>`),
|
||
|
|
reComment: regexp.MustCompile(`(?s)<!--.*?-->`),
|
||
|
|
|
||
|
|
reAttrXMLNs: regexp.MustCompile(`(?s)\s+xmlns\s*=\s*"[^"]*"`),
|
||
|
|
reAttrSize: regexp.MustCompile(`(?s)\s+(width|height)\s*=\s*"[^"]+"`),
|
||
|
|
reAttrClassPrefix: regexp.MustCompile(`(?s)\s+class\s*=\s*"`),
|
||
|
|
}
|
||
|
|
})
|
||
|
|
data = normalizeVars.reXMLDoc.ReplaceAll(data, nil)
|
||
|
|
data = normalizeVars.reComment.ReplaceAll(data, nil)
|
||
|
|
|
||
|
|
data = bytes.TrimSpace(data)
|
||
|
|
svgTag, svgRemaining, ok := bytes.Cut(data, []byte(">"))
|
||
|
|
if !ok || !bytes.HasPrefix(svgTag, []byte(`<svg`)) {
|
||
|
|
return data
|
||
|
|
}
|
||
|
|
normalized := bytes.Clone(svgTag)
|
||
|
|
normalized = normalizeVars.reAttrXMLNs.ReplaceAll(normalized, nil)
|
||
|
|
normalized = normalizeVars.reAttrSize.ReplaceAll(normalized, nil)
|
||
|
|
normalized = normalizeVars.reAttrClassPrefix.ReplaceAll(normalized, []byte(` class="`))
|
||
|
|
normalized = bytes.TrimSpace(normalized)
|
||
|
|
normalized = fmt.Appendf(normalized, ` width="%d" height="%d"`, size, size)
|
||
|
|
if !bytes.Contains(normalized, []byte(` class="`)) {
|
||
|
|
normalized = append(normalized, ` class="svg"`...)
|
||
|
|
}
|
||
|
|
normalized = append(normalized, '>')
|
||
|
|
normalized = append(normalized, svgRemaining...)
|
||
|
|
return normalized
|
||
|
|
}
|