func (o *Minifier) shortenDimension(b []byte) ([]byte, int) {
if n, m := parse.Dimension(b); n > 0 {
unit := b[n : n+m]
b = minify.Number(b[:n], o.Decimals)
if len(b) != 1 || b[0] != '0' {
if m == 2 && unit[0] == 'p' && unit[1] == 'x' {
unit = nil
} else if m > 1 { // only percentage is length 1
parse.ToLower(unit)
}
b = append(b, unit...)
}
return b, n + m
}
return b, 0
}
// Minify minifies SVG data, it reads from r and writes to w.
func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, _ map[string]string) error {
var tag svg.Hash
defaultStyleType := cssMimeBytes
defaultStyleParams := map[string]string(nil)
defaultInlineStyleParams := map[string]string{"inline": "1"}
p := NewPathData(o)
minifyBuffer := buffer.NewWriter(make([]byte, 0, 64))
attrByteBuffer := make([]byte, 0, 64)
gStack := make([]bool, 0)
l := xml.NewLexer(r)
tb := NewTokenBuffer(l)
for {
t := *tb.Shift()
SWITCH:
switch t.TokenType {
case xml.ErrorToken:
if l.Err() == io.EOF {
return nil
}
return l.Err()
case xml.DOCTYPEToken:
if len(t.Text) > 0 && t.Text[len(t.Text)-1] == ']' {
if _, err := w.Write(t.Data); err != nil {
return err
}
}
case xml.TextToken:
t.Data = parse.ReplaceMultipleWhitespace(parse.TrimWhitespace(t.Data))
if tag == svg.Style && len(t.Data) > 0 {
if err := m.MinifyMimetype(defaultStyleType, w, buffer.NewReader(t.Data), defaultStyleParams); err != nil {
if err != minify.ErrNotExist {
return err
} else if _, err := w.Write(t.Data); err != nil {
return err
}
}
} else if _, err := w.Write(t.Data); err != nil {
return err
}
case xml.CDATAToken:
if tag == svg.Style {
minifyBuffer.Reset()
if err := m.MinifyMimetype(defaultStyleType, minifyBuffer, buffer.NewReader(t.Text), defaultStyleParams); err == nil {
t.Data = append(t.Data[:9], minifyBuffer.Bytes()...)
t.Text = t.Data[9:]
t.Data = append(t.Data, cdataEndBytes...)
} else if err != minify.ErrNotExist {
return err
}
}
var useText bool
if t.Text, useText = xml.EscapeCDATAVal(&attrByteBuffer, t.Text); useText {
t.Text = parse.ReplaceMultipleWhitespace(parse.TrimWhitespace(t.Text))
if _, err := w.Write(t.Text); err != nil {
return err
}
} else if _, err := w.Write(t.Data); err != nil {
return err
}
case xml.StartTagPIToken:
for {
if t := *tb.Shift(); t.TokenType == xml.StartTagClosePIToken || t.TokenType == xml.ErrorToken {
break
}
}
case xml.StartTagToken:
tag = t.Hash
if containerTagMap[tag] { // skip empty containers
i := 0
for {
next := tb.Peek(i)
i++
if next.TokenType == xml.EndTagToken && next.Hash == tag || next.TokenType == xml.StartTagCloseVoidToken || next.TokenType == xml.ErrorToken {
for j := 0; j < i; j++ {
tb.Shift()
}
break SWITCH
} else if next.TokenType != xml.AttributeToken && next.TokenType != xml.StartTagCloseToken {
break
}
}
if tag == svg.G {
if tb.Peek(0).TokenType == xml.StartTagCloseToken {
gStack = append(gStack, false)
tb.Shift()
break
}
gStack = append(gStack, true)
}
} else if tag == svg.Metadata {
skipTag(tb, tag)
break
} else if tag == svg.Line {
o.shortenLine(tb, &t, p)
} else if tag == svg.Rect && !o.shortenRect(tb, &t, p) {
skipTag(tb, tag)
break
} else if tag == svg.Polygon || tag == svg.Polyline {
o.shortenPoly(tb, &t, p)
}
if _, err := w.Write(t.Data); err != nil {
return err
}
case xml.AttributeToken:
if len(t.AttrVal) == 0 || t.Text == nil { // data is nil when attribute has been removed
continue
}
attr := t.Hash
val := t.AttrVal
if n, m := parse.Dimension(val); n+m == len(val) { // TODO: inefficient, temporary measure
val, _ = o.shortenDimension(val)
}
if attr == svg.Xml_Space && parse.Equal(val, []byte("preserve")) ||
tag == svg.Svg && (attr == svg.Version && parse.Equal(val, []byte("1.1")) ||
attr == svg.X && parse.Equal(val, []byte("0")) ||
attr == svg.Y && parse.Equal(val, []byte("0")) ||
attr == svg.Width && parse.Equal(val, []byte("100%")) ||
attr == svg.Height && parse.Equal(val, []byte("100%")) ||
attr == svg.PreserveAspectRatio && parse.Equal(val, []byte("xMidYMid meet")) ||
attr == svg.BaseProfile && parse.Equal(val, []byte("none")) ||
attr == svg.ContentScriptType && parse.Equal(val, []byte("application/ecmascript")) ||
attr == svg.ContentStyleType && parse.Equal(val, []byte("text/css"))) ||
tag == svg.Style && attr == svg.Type && parse.Equal(val, []byte("text/css")) {
continue
}
if _, err := w.Write(spaceBytes); err != nil {
return err
}
if _, err := w.Write(t.Text); err != nil {
return err
}
if _, err := w.Write(isBytes); err != nil {
return err
}
if tag == svg.Svg && attr == svg.ContentStyleType {
val = minify.ContentType(val)
defaultStyleType = val
} else if attr == svg.Style {
minifyBuffer.Reset()
if err := m.MinifyMimetype(defaultStyleType, minifyBuffer, buffer.NewReader(val), defaultInlineStyleParams); err == nil {
val = minifyBuffer.Bytes()
} else if err != minify.ErrNotExist {
return err
}
} else if attr == svg.D {
val = p.ShortenPathData(val)
} else if attr == svg.ViewBox {
j := 0
newVal := val[:0]
for i := 0; i < 4; i++ {
if i != 0 {
if j >= len(val) || val[j] != ' ' && val[j] != ',' {
newVal = append(newVal, val[j:]...)
break
}
newVal = append(newVal, ' ')
j++
}
if dim, n := o.shortenDimension(val[j:]); n > 0 {
newVal = append(newVal, dim...)
j += n
} else {
newVal = append(newVal, val[j:]...)
break
}
}
val = newVal
} else if colorAttrMap[attr] && len(val) > 0 {
parse.ToLower(val)
if val[0] == '#' {
if name, ok := minifyCSS.ShortenColorHex[string(val)]; ok {
val = name
} else if len(val) == 7 && val[1] == val[2] && val[3] == val[4] && val[5] == val[6] {
val[2] = val[3]
val[3] = val[5]
val = val[:4]
}
} else if hex, ok := minifyCSS.ShortenColorName[css.ToHash(val)]; ok {
val = hex
} else if len(val) > 5 && parse.Equal(val[:4], []byte("rgb(")) && val[len(val)-1] == ')' {
// TODO: handle rgb(x, y, z) and hsl(x, y, z)
}
}
// prefer single or double quotes depending on what occurs more often in value
val = xml.EscapeAttrVal(&attrByteBuffer, val)
if _, err := w.Write(val); err != nil {
return err
}
case xml.StartTagCloseToken:
next := tb.Peek(0)
skipExtra := false
if next.TokenType == xml.TextToken && parse.IsAllWhitespace(next.Data) {
next = tb.Peek(1)
skipExtra = true
}
if next.TokenType == xml.EndTagToken {
// collapse empty tags to single void tag
tb.Shift()
if skipExtra {
tb.Shift()
}
if _, err := w.Write(voidBytes); err != nil {
return err
}
} else {
if _, err := w.Write(t.Data); err != nil {
return err
}
}
case xml.StartTagCloseVoidToken:
tag = 0
if _, err := w.Write(t.Data); err != nil {
return err
}
case xml.EndTagToken:
tag = 0
if t.Hash == svg.G && len(gStack) > 0 {
if !gStack[len(gStack)-1] {
gStack = gStack[:len(gStack)-1]
break
}
gStack = gStack[:len(gStack)-1]
}
if len(t.Data) > 3+len(t.Text) {
t.Data[2+len(t.Text)] = '>'
t.Data = t.Data[:3+len(t.Text)]
}
if _, err := w.Write(t.Data); err != nil {
return err
}
}
}
}
// Minify minifies SVG data, it reads from r and writes to w.
func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, _ map[string]string) error {
var tag svg.Hash
defaultStyleType := "text/css"
defaultInlineStyleType := "text/css;inline=1"
attrMinifyBuffer := buffer.NewWriter(make([]byte, 0, 64))
attrByteBuffer := make([]byte, 0, 64)
l := xml.NewLexer(r)
tb := NewTokenBuffer(l)
for {
t := *tb.Shift()
if t.TokenType == xml.CDATAToken {
var useText bool
if t.Data, useText = xml.EscapeCDATAVal(&attrByteBuffer, t.Data); useText {
t.TokenType = xml.TextToken
}
}
SWITCH:
switch t.TokenType {
case xml.ErrorToken:
if l.Err() == io.EOF {
return nil
}
return l.Err()
case xml.TextToken:
t.Data = parse.ReplaceMultipleWhitespace(parse.TrimWhitespace(t.Data))
if tag == svg.Style && len(t.Data) > 0 {
if err := m.Minify(defaultStyleType, w, buffer.NewReader(t.Data)); err != nil {
if err == minify.ErrNotExist { // no minifier, write the original
if _, err := w.Write(t.Data); err != nil {
return err
}
} else {
return err
}
}
} else if _, err := w.Write(t.Data); err != nil {
return err
}
case xml.CDATAToken:
if _, err := w.Write(cdataStartBytes); err != nil {
return err
}
t.Data = parse.ReplaceMultipleWhitespace(parse.TrimWhitespace(t.Data))
if tag == svg.Style && len(t.Data) > 0 {
if err := m.Minify(defaultStyleType, w, buffer.NewReader(t.Data)); err != nil {
if err == minify.ErrNotExist { // no minifier, write the original
if _, err := w.Write(t.Data); err != nil {
return err
}
} else {
return err
}
}
} else if _, err := w.Write(t.Data); err != nil {
return err
}
if _, err := w.Write(cdataEndBytes); err != nil {
return err
}
case xml.StartTagPIToken:
for {
if t := *tb.Shift(); t.TokenType == xml.StartTagClosePIToken || t.TokenType == xml.ErrorToken {
break
}
}
case xml.StartTagToken:
tag = t.Hash
if containerTagMap[t.Hash] { // skip empty containers
i := 0
for {
next := tb.Peek(i)
i++
if next.TokenType == xml.EndTagToken && next.Hash == t.Hash || next.TokenType == xml.StartTagCloseVoidToken || next.TokenType == xml.ErrorToken {
for j := 0; j < i; j++ {
tb.Shift()
}
break SWITCH
} else if next.TokenType != xml.AttributeToken && next.TokenType != xml.StartTagCloseToken {
break
}
}
} else if t.Hash == svg.Metadata {
for {
if next := *tb.Shift(); (next.TokenType == xml.EndTagToken || next.TokenType == xml.StartTagCloseVoidToken) && next.Hash == t.Hash || next.TokenType == xml.ErrorToken {
break
}
}
break
} else if t.Hash == svg.Line || t.Hash == svg.Rect {
// TODO: shape2path also for polygon and polyline
// x1, y1, x2, y2 float64 := 0, 0, 0, 0
// valid := true
// i := 0
// for {
// next := tb.Peek(i)
// i++
// if next.TokenType != xml.AttributeToken {
// break
// }
// v *int
// attr := svg.ToHash(next.Data)
// if tag == svg.Line {
// if attr == svg.X1 {
// v = &x1
// } else if attr == svg.Y1 {
// v = &y1
// } else if attr == svg.X2 {
// v = &x2
// } else if attr == svg.Y2 {
// v = &Y2
// } else {
// continue
// }
// } else if attr == svg.X { // rect
// v = &x1
// } else if attr == svg.Y {
// v = &y1
// } else if attr == svg.Width {
// v = &x2
// } else if attr == svg.Height {
// v = &Y2
// } else if attr == svg.Rx || attr == svg.Ry {
// valid = false
// break
// } else {
// continue
// }
// }
// if valid {
// t.Data = pathBytes
// }
}
if _, err := w.Write(ltBytes); err != nil {
return err
}
if _, err := w.Write(t.Data); err != nil {
return err
}
case xml.AttributeToken:
if len(t.AttrVal) < 2 {
continue
}
val := parse.ReplaceMultipleWhitespace(parse.TrimWhitespace(t.AttrVal[1 : len(t.AttrVal)-1]))
if tag == svg.Svg && t.Hash == svg.Version {
continue
}
if _, err := w.Write(spaceBytes); err != nil {
return err
}
if _, err := w.Write(t.Data); err != nil {
return err
}
if _, err := w.Write(isBytes); err != nil {
return err
}
if tag == svg.Svg && t.Hash == svg.ContentStyleType {
val = minify.ContentType(val)
defaultStyleType = string(val)
defaultInlineStyleType = defaultStyleType + ";inline=1"
} else if t.Hash == svg.Style {
attrMinifyBuffer.Reset()
if m.Minify(defaultInlineStyleType, attrMinifyBuffer, buffer.NewReader(val)) == nil {
val = attrMinifyBuffer.Bytes()
}
} else if t.Hash == svg.D {
val = shortenPathData(val)
} else if t.Hash == svg.ViewBox {
j := 0
newVal := val[:0]
for i := 0; i < 4; i++ {
if i != 0 {
if j >= len(val) || val[j] != ' ' && val[j] != ',' {
newVal = append(newVal, val[j:]...)
break
}
newVal = append(newVal, ' ')
j++
}
if dim, n := shortenDimension(val[j:]); n > 0 {
newVal = append(newVal, dim...)
j += n
} else {
newVal = append(newVal, val[j:]...)
break
}
}
val = newVal
} else if colorAttrMap[t.Hash] && len(val) > 0 {
parse.ToLower(val)
if val[0] == '#' {
if name, ok := minifyCSS.ShortenColorHex[string(val)]; ok {
val = name
} else if len(val) == 7 && val[1] == val[2] && val[3] == val[4] && val[5] == val[6] {
val[2] = val[3]
val[3] = val[5]
val = val[:4]
}
} else if hex, ok := minifyCSS.ShortenColorName[css.ToHash(val)]; ok {
val = hex
} else if len(val) > 5 && parse.Equal(val[:4], []byte("rgb(")) && val[len(val)-1] == ')' {
// TODO: handle rgb(x, y, z) and hsl(x, y, z)
}
} else if n, m := parse.Dimension(val); n+m == len(val) { // TODO: inefficient, temporary measure
val, _ = shortenDimension(val)
}
// prefer single or double quotes depending on what occurs more often in value
val = xml.EscapeAttrVal(&attrByteBuffer, val)
if _, err := w.Write(val); err != nil {
return err
}
case xml.StartTagCloseToken:
next := tb.Peek(0)
skipExtra := false
if next.TokenType == xml.TextToken && parse.IsAllWhitespace(next.Data) {
next = tb.Peek(1)
skipExtra = true
}
if next.TokenType == xml.EndTagToken {
// collapse empty tags to single void tag
tb.Shift()
if skipExtra {
tb.Shift()
}
if _, err := w.Write(voidBytes); err != nil {
return err
}
} else {
if _, err := w.Write(gtBytes); err != nil {
return err
}
}
case xml.StartTagCloseVoidToken:
if _, err := w.Write(voidBytes); err != nil {
return err
}
case xml.EndTagToken:
if _, err := w.Write(endBytes); err != nil {
return err
}
if _, err := w.Write(t.Data); err != nil {
return err
}
if _, err := w.Write(gtBytes); err != nil {
return err
}
}
}
}