1012 lines
32 KiB
Go
1012 lines
32 KiB
Go
// Package css minifies CSS3 following the specifications at http://www.w3.org/TR/css-syntax-3/.
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package css
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import (
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"bytes"
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"encoding/hex"
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"fmt"
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"io"
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"strconv"
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"github.com/tdewolff/minify/v2"
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"github.com/tdewolff/parse/v2"
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"github.com/tdewolff/parse/v2/css"
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strconvParse "github.com/tdewolff/parse/v2/strconv"
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)
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var (
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spaceBytes = []byte(" ")
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colonBytes = []byte(":")
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semicolonBytes = []byte(";")
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commaBytes = []byte(",")
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leftBracketBytes = []byte("{")
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rightBracketBytes = []byte("}")
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zeroBytes = []byte("0")
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transparentBytes = []byte("transparent")
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importantBytes = []byte("!important")
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)
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type cssMinifier struct {
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m *minify.M
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w io.Writer
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p *css.Parser
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o *Minifier
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valuesBuffer []Token
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}
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////////////////////////////////////////////////////////////////
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// DefaultMinifier is the default minifier.
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var DefaultMinifier = &Minifier{Decimals: -1, KeepCSS2: false}
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// Minifier is a CSS minifier.
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type Minifier struct {
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Decimals int
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KeepCSS2 bool
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}
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// Minify minifies CSS data, it reads from r and writes to w.
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func Minify(m *minify.M, w io.Writer, r io.Reader, params map[string]string) error {
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return DefaultMinifier.Minify(m, w, r, params)
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}
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type Token struct {
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css.TokenType
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Data []byte
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Components []css.Token // only filled for functions
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}
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func (t Token) String() string {
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if len(t.Components) == 0 {
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return t.TokenType.String() + "(" + string(t.Data) + ")"
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}
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return fmt.Sprint(t.Components)
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}
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func (a Token) Equal(b Token) bool {
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if a.TokenType == b.TokenType && bytes.Equal(a.Data, b.Data) && len(a.Components) == len(b.Components) {
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for i := 0; i < len(a.Components); i++ {
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if a.Components[i].TokenType != b.Components[i].TokenType || !bytes.Equal(a.Components[i].Data, b.Components[i].Data) {
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return false
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}
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}
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return true
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}
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return false
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}
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// Minify minifies CSS data, it reads from r and writes to w.
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func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, params map[string]string) error {
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isInline := params != nil && params["inline"] == "1"
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c := &cssMinifier{
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m: m,
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w: w,
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p: css.NewParser(r, isInline),
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o: o,
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}
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defer c.p.Restore()
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if err := c.minifyGrammar(); err != nil && err != io.EOF {
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return err
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}
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return nil
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}
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func (c *cssMinifier) minifyGrammar() error {
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semicolonQueued := false
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for {
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gt, _, data := c.p.Next()
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switch gt {
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case css.ErrorGrammar:
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if _, ok := c.p.Err().(*parse.Error); ok {
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if semicolonQueued {
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if _, err := c.w.Write(semicolonBytes); err != nil {
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return err
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}
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}
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// write out the offending declaration (but save the semicolon)
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vals := c.p.Values()
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if len(vals) > 0 && vals[len(vals)-1].TokenType == css.SemicolonToken {
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vals = vals[:len(vals)-1]
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semicolonQueued = true
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}
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for _, val := range vals {
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if _, err := c.w.Write(val.Data); err != nil {
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return err
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}
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}
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continue
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}
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return c.p.Err()
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case css.EndAtRuleGrammar, css.EndRulesetGrammar:
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if _, err := c.w.Write(rightBracketBytes); err != nil {
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return err
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}
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semicolonQueued = false
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continue
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}
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if semicolonQueued {
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if _, err := c.w.Write(semicolonBytes); err != nil {
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return err
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}
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semicolonQueued = false
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}
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switch gt {
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case css.AtRuleGrammar:
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if _, err := c.w.Write(data); err != nil {
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return err
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}
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values := c.p.Values()
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if css.ToHash(data[1:]) == css.Import && len(values) == 2 && values[1].TokenType == css.URLToken {
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url := values[1].Data
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if url[4] != '"' && url[4] != '\'' {
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url = url[3:]
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url[0] = '"'
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url[len(url)-1] = '"'
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} else {
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url = url[4 : len(url)-1]
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}
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values[1].Data = url
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}
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for _, val := range values {
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if _, err := c.w.Write(val.Data); err != nil {
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return err
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}
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}
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semicolonQueued = true
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case css.BeginAtRuleGrammar:
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if _, err := c.w.Write(data); err != nil {
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return err
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}
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for _, val := range c.p.Values() {
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if _, err := c.w.Write(val.Data); err != nil {
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return err
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}
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}
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if _, err := c.w.Write(leftBracketBytes); err != nil {
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return err
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}
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case css.QualifiedRuleGrammar:
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if err := c.minifySelectors(data, c.p.Values()); err != nil {
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return err
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}
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if _, err := c.w.Write(commaBytes); err != nil {
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return err
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}
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case css.BeginRulesetGrammar:
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if err := c.minifySelectors(data, c.p.Values()); err != nil {
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return err
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}
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if _, err := c.w.Write(leftBracketBytes); err != nil {
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return err
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}
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case css.DeclarationGrammar:
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if _, err := c.w.Write(data); err != nil {
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return err
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}
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if _, err := c.w.Write(colonBytes); err != nil {
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return err
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}
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if err := c.minifyDeclaration(data, c.p.Values()); err != nil {
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return err
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}
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semicolonQueued = true
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case css.CustomPropertyGrammar:
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if _, err := c.w.Write(data); err != nil {
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return err
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}
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if _, err := c.w.Write(colonBytes); err != nil {
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return err
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}
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if _, err := c.w.Write(c.p.Values()[0].Data); err != nil {
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return err
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}
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semicolonQueued = true
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case css.CommentGrammar:
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if len(data) > 5 && data[1] == '*' && data[2] == '!' {
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if _, err := c.w.Write(data[:3]); err != nil {
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return err
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}
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comment := parse.TrimWhitespace(parse.ReplaceMultipleWhitespace(data[3 : len(data)-2]))
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if _, err := c.w.Write(comment); err != nil {
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return err
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}
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if _, err := c.w.Write(data[len(data)-2:]); err != nil {
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return err
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}
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}
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default:
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if _, err := c.w.Write(data); err != nil {
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return err
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}
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}
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}
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}
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func (c *cssMinifier) minifySelectors(property []byte, values []css.Token) error {
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inAttr := false
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isClass := false
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for _, val := range c.p.Values() {
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if !inAttr {
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if val.TokenType == css.IdentToken {
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if !isClass {
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parse.ToLower(val.Data)
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}
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isClass = false
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} else if val.TokenType == css.DelimToken && val.Data[0] == '.' {
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isClass = true
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} else if val.TokenType == css.LeftBracketToken {
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inAttr = true
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}
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} else {
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if val.TokenType == css.StringToken && len(val.Data) > 2 {
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s := val.Data[1 : len(val.Data)-1]
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if css.IsIdent(s) {
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if _, err := c.w.Write(s); err != nil {
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return err
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}
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continue
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}
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} else if val.TokenType == css.RightBracketToken {
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inAttr = false
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} else if val.TokenType == css.IdentToken && len(val.Data) == 1 && (val.Data[0] == 'i' || val.Data[0] == 'I') {
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if _, err := c.w.Write(spaceBytes); err != nil {
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return err
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}
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}
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}
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if _, err := c.w.Write(val.Data); err != nil {
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return err
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}
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}
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return nil
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}
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func (c *cssMinifier) minifyDeclaration(property []byte, components []css.Token) error {
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if len(components) == 0 {
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return nil
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}
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// Strip !important from the component list, this will be added later separately
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important := false
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if len(components) > 2 && components[len(components)-2].TokenType == css.DelimToken && components[len(components)-2].Data[0] == '!' && css.ToHash(components[len(components)-1].Data) == css.Important {
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components = components[:len(components)-2]
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important = true
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}
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// Check if this is a simple list of values separated by whitespace or commas, otherwise we'll not be processing
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simple := true
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prevSep := true
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values := c.valuesBuffer[:0]
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for i := 0; i < len(components); i++ {
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comp := components[i]
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tt := comp.TokenType
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if tt == css.LeftParenthesisToken || tt == css.LeftBraceToken || tt == css.LeftBracketToken ||
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tt == css.RightParenthesisToken || tt == css.RightBraceToken || tt == css.RightBracketToken {
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simple = false
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break
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}
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if !prevSep && tt != css.WhitespaceToken && tt != css.CommaToken && (tt != css.DelimToken || comp.Data[0] != '/') {
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simple = false
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break
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}
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if tt == css.WhitespaceToken || tt == css.CommaToken || tt == css.DelimToken && comp.Data[0] == '/' {
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prevSep = true
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if tt != css.WhitespaceToken {
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values = append(values, Token{tt, comp.Data, nil})
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}
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} else if tt == css.FunctionToken {
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prevSep = false
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j := i + 1
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level := 0
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for ; j < len(components); j++ {
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if components[j].TokenType == css.LeftParenthesisToken {
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level++
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} else if components[j].TokenType == css.RightParenthesisToken {
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if level == 0 {
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j++
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break
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}
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level--
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}
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}
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values = append(values, Token{components[i].TokenType, components[i].Data, components[i:j]})
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i = j - 1
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} else {
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prevSep = false
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values = append(values, Token{components[i].TokenType, components[i].Data, nil})
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}
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}
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c.valuesBuffer = values
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prop := css.ToHash(property)
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// Do not process complex values (eg. containing blocks or is not alternated between whitespace/commas and flat values
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if !simple {
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if prop == css.Filter && len(components) == 11 {
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if bytes.Equal(components[0].Data, []byte("progid")) &&
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components[1].TokenType == css.ColonToken &&
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bytes.Equal(components[2].Data, []byte("DXImageTransform")) &&
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components[3].Data[0] == '.' &&
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bytes.Equal(components[4].Data, []byte("Microsoft")) &&
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components[5].Data[0] == '.' &&
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bytes.Equal(components[6].Data, []byte("Alpha(")) &&
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bytes.Equal(parse.ToLower(components[7].Data), []byte("opacity")) &&
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components[8].Data[0] == '=' &&
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components[10].Data[0] == ')' {
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components = components[6:]
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components[0].Data = []byte("alpha(")
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}
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}
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for _, component := range components {
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if _, err := c.w.Write(component.Data); err != nil {
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return err
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}
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}
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if important {
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if _, err := c.w.Write(importantBytes); err != nil {
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return err
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}
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}
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return nil
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}
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for i := range values {
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values[i].TokenType, values[i].Data = c.shortenToken(prop, values[i].TokenType, values[i].Data)
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}
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if len(values) > 0 {
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values = c.minifyProperty(prop, values)
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}
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prevSep = true
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for _, value := range values {
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if !prevSep && value.TokenType != css.CommaToken && (value.TokenType != css.DelimToken || value.Data[0] != '/') {
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if _, err := c.w.Write(spaceBytes); err != nil {
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return err
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}
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}
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if value.TokenType == css.FunctionToken {
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err := c.minifyFunction(value.Components)
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if err != nil {
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return err
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}
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} else if _, err := c.w.Write(value.Data); err != nil {
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return err
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}
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if value.TokenType == css.CommaToken || value.TokenType == css.DelimToken && value.Data[0] == '/' || value.TokenType == css.FunctionToken || value.TokenType == css.URLToken {
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prevSep = true
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} else {
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prevSep = false
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}
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}
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if important {
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if _, err := c.w.Write(importantBytes); err != nil {
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return err
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}
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}
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return nil
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}
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func (c *cssMinifier) minifyProperty(prop css.Hash, values []Token) []Token {
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switch prop {
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case css.Font:
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if len(values) > 1 {
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// the font-families are separated by commas and are at the end of font
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// get index for the first font-family given
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i := len(values) - 1
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for j, value := range values[2:] {
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if value.TokenType == css.CommaToken {
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i = 2 + j - 1 // identifier before first comma is a font-family
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break
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}
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}
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i--
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// advance i while still at font-families when they contain spaces but no quotes
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for ; i > 0; i-- { // i cannot be 0, font-family must be prepended by font-size
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if values[i-1].TokenType == css.DelimToken && values[i-1].Data[0] == '/' {
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break
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} else if values[i].TokenType != css.IdentToken && values[i].TokenType != css.StringToken {
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break
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} else if values[i].TokenType == css.IdentToken {
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h := css.ToHash(values[i].Data)
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// inherit, initial and unset are followed by an IdentToken/StringToken, so must be for font-size
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if h == css.Xx_Small || h == css.X_Small || h == css.Small || h == css.Medium || h == css.Large || h == css.X_Large || h == css.Xx_Large || h == css.Smaller || h == css.Larger || h == css.Inherit || h == css.Initial || h == css.Unset {
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break
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}
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}
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}
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|
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// font-family minified in place
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values = append(values[:i+1], c.minifyProperty(css.Font_Family, values[i+1:])...)
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if i > 0 {
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// line-height
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if i > 1 && values[i-1].TokenType == css.DelimToken && values[i-1].Data[0] == '/' {
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if values[i].TokenType == css.IdentToken && bytes.Equal(values[i].Data, []byte("normal")) {
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values = append(values[:i-1], values[i+1:]...)
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}
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i -= 2
|
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}
|
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|
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// font-size
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i--
|
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|
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for ; i > -1; i-- {
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if values[i].TokenType == css.IdentToken {
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val := css.ToHash(values[i].Data)
|
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if val == css.Normal {
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values = append(values[:i], values[i+1:]...)
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} else if val == css.Bold {
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values[i].TokenType = css.NumberToken
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values[i].Data = []byte("700")
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}
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} else if values[i].TokenType == css.NumberToken && bytes.Equal(values[i].Data, []byte("400")) {
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values = append(values[:i], values[i+1:]...)
|
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}
|
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}
|
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}
|
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}
|
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case css.Font_Family:
|
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for i, value := range values {
|
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if value.TokenType == css.StringToken && len(value.Data) > 2 {
|
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unquote := true
|
|
parse.ToLower(value.Data)
|
|
s := value.Data[1 : len(value.Data)-1]
|
|
if len(s) > 0 {
|
|
for _, split := range bytes.Split(s, spaceBytes) {
|
|
// if len is zero, it contains two consecutive spaces
|
|
if len(split) == 0 || !css.IsIdent(split) {
|
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unquote = false
|
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break
|
|
}
|
|
}
|
|
}
|
|
if unquote {
|
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values[i].Data = s
|
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}
|
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}
|
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}
|
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case css.Font_Weight:
|
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if len(values) == 1 && values[0].TokenType == css.IdentToken {
|
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val := css.ToHash(values[0].Data)
|
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if val == css.Normal {
|
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values[0].TokenType = css.NumberToken
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values[0].Data = []byte("400")
|
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} else if val == css.Bold {
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values[0].TokenType = css.NumberToken
|
|
values[0].Data = []byte("700")
|
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}
|
|
}
|
|
case css.Url:
|
|
for i := 0; i < len(values); i++ {
|
|
if values[i].TokenType == css.FunctionToken && 2 < len(values[i].Components) {
|
|
fun := values[i].Components
|
|
name := css.ToHash(fun[0].Data[0 : len(fun[0].Data)-1])
|
|
if name == css.Local {
|
|
data := fun[1].Data
|
|
if data[0] == '\'' || data[0] == '"' {
|
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data = removeStringNewlinex(data)
|
|
if css.IsURLUnquoted(data[1 : len(data)-1]) {
|
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data = data[1 : len(data)-1]
|
|
}
|
|
fun[1].Data = data
|
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}
|
|
}
|
|
}
|
|
}
|
|
case css.Margin, css.Padding, css.Border_Width:
|
|
switch len(values) {
|
|
case 2:
|
|
if values[0].Equal(values[1]) {
|
|
values = values[:1]
|
|
}
|
|
case 3:
|
|
if values[0].Equal(values[1]) && values[0].Equal(values[2]) {
|
|
values = values[:1]
|
|
} else if values[0].Equal(values[2]) {
|
|
values = values[:2]
|
|
}
|
|
case 4:
|
|
if values[0].Equal(values[1]) && values[0].Equal(values[2]) && values[0].Equal(values[3]) {
|
|
values = values[:1]
|
|
} else if values[0].Equal(values[2]) && values[1].Equal(values[3]) {
|
|
values = values[:2]
|
|
} else if values[1].Equal(values[3]) {
|
|
values = values[:3]
|
|
}
|
|
}
|
|
case css.Border, css.Border_Bottom, css.Border_Left, css.Border_Right, css.Border_Top:
|
|
for i := 0; i < len(values); i++ {
|
|
if values[i].TokenType == css.IdentToken {
|
|
val := css.ToHash(values[i].Data)
|
|
if val == css.None || val == css.Currentcolor || val == css.Medium {
|
|
values = append(values[:i], values[i+1:]...)
|
|
i--
|
|
}
|
|
}
|
|
}
|
|
if len(values) == 0 {
|
|
values = []Token{{css.IdentToken, []byte("none"), nil}}
|
|
}
|
|
case css.Outline:
|
|
for i := 0; i < len(values); i++ {
|
|
if values[i].TokenType == css.IdentToken {
|
|
val := css.ToHash(values[i].Data)
|
|
if val == css.None || val == css.Medium { // color=invert is not supported by all browsers
|
|
values = append(values[:i], values[i+1:]...)
|
|
i--
|
|
}
|
|
}
|
|
}
|
|
if len(values) == 0 {
|
|
values = []Token{{css.IdentToken, []byte("none"), nil}}
|
|
}
|
|
case css.Background:
|
|
// TODO: multiple background layers separated by comma
|
|
hasSize := false
|
|
for i := 0; i < len(values); i++ {
|
|
if values[i].TokenType == css.DelimToken && values[i].Data[0] == '/' {
|
|
hasSize = true
|
|
// background-size consists of either [<length-percentage> | auto | cover | contain] or [<length-percentage> | auto]{2}
|
|
// we can only minify the latter
|
|
if i+1 < len(values) && (values[i+1].TokenType == css.NumberToken || values[i+1].TokenType == css.PercentageToken || values[i+1].TokenType == css.IdentToken && bytes.Equal(values[i+1].Data, []byte("auto")) || values[i+1].TokenType == css.FunctionToken) {
|
|
if i+2 < len(values) && (values[i+2].TokenType == css.NumberToken || values[i+2].TokenType == css.PercentageToken || values[i+2].TokenType == css.IdentToken && bytes.Equal(values[i+2].Data, []byte("auto")) || values[i+2].TokenType == css.FunctionToken) {
|
|
sizeValues := c.minifyProperty(css.Background_Size, values[i+1:i+3])
|
|
if len(sizeValues) == 1 && bytes.Equal(sizeValues[0].Data, []byte("auto")) {
|
|
// remove background-size if it is '/ auto' after minifying the property
|
|
values = append(values[:i], values[i+3:]...)
|
|
hasSize = false
|
|
i--
|
|
} else {
|
|
values = append(values[:i+1], append(sizeValues, values[i+3:]...)...)
|
|
i += len(sizeValues) - 1
|
|
}
|
|
} else if values[i+1].TokenType == css.IdentToken && bytes.Equal(values[i+1].Data, []byte("auto")) {
|
|
// remove background-size if it is '/ auto'
|
|
values = append(values[:i], values[i+2:]...)
|
|
hasSize = false
|
|
i--
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
var h css.Hash
|
|
iPaddingBox := -1 // position of background-origin that is padding-box
|
|
for i := 0; i < len(values); i++ {
|
|
if values[i].TokenType == css.IdentToken {
|
|
h = css.ToHash(values[i].Data)
|
|
if i+1 < len(values) && values[i+1].TokenType == css.IdentToken && (h == css.Space || h == css.Round || h == css.Repeat || h == css.No_Repeat) {
|
|
if h2 := css.ToHash(values[i+1].Data); h2 == css.Space || h2 == css.Round || h2 == css.Repeat || h2 == css.No_Repeat {
|
|
repeatValues := c.minifyProperty(css.Background_Repeat, values[i:i+2])
|
|
if len(repeatValues) == 1 && bytes.Equal(repeatValues[0].Data, []byte("repeat")) {
|
|
values = append(values[:i], values[i+2:]...)
|
|
i--
|
|
} else {
|
|
values = append(values[:i], append(repeatValues, values[i+2:]...)...)
|
|
i += len(repeatValues) - 1
|
|
}
|
|
continue
|
|
}
|
|
} else if h == css.None || h == css.Scroll || h == css.Transparent {
|
|
values = append(values[:i], values[i+1:]...)
|
|
i--
|
|
continue
|
|
} else if h == css.Border_Box || h == css.Padding_Box {
|
|
if iPaddingBox == -1 && h == css.Padding_Box { // background-origin
|
|
iPaddingBox = i
|
|
} else if iPaddingBox != -1 && h == css.Border_Box { // background-clip
|
|
values = append(values[:i], values[i+1:]...)
|
|
values = append(values[:iPaddingBox], values[iPaddingBox+1:]...)
|
|
i -= 2
|
|
}
|
|
continue
|
|
}
|
|
} else if values[i].TokenType == css.HashToken && bytes.Equal(values[i].Data, []byte("#0000")) {
|
|
values = append(values[:i], values[i+1:]...)
|
|
i--
|
|
continue
|
|
}
|
|
|
|
// background-position or background-size
|
|
// TODO: allow only functions that return Number, Percentage or Dimension token. Make whitelist?
|
|
if values[i].TokenType == css.NumberToken || values[i].TokenType == css.DimensionToken || values[i].TokenType == css.PercentageToken || values[i].TokenType == css.IdentToken && (h == css.Left || h == css.Right || h == css.Top || h == css.Bottom || h == css.Center) || values[i].TokenType == css.FunctionToken && bytes.Equal(values[i].Data, []byte("calc(")) {
|
|
j := i + 1
|
|
for ; j < len(values); j++ {
|
|
if values[j].TokenType == css.IdentToken {
|
|
h := css.ToHash(values[j].Data)
|
|
if h == css.Left || h == css.Right || h == css.Top || h == css.Bottom || h == css.Center {
|
|
continue
|
|
}
|
|
} else if values[j].TokenType == css.NumberToken || values[j].TokenType == css.DimensionToken || values[j].TokenType == css.PercentageToken || values[i].TokenType == css.FunctionToken && bytes.Equal(values[i].Data, []byte("calc(")) {
|
|
continue
|
|
}
|
|
break
|
|
}
|
|
|
|
positionValues := c.minifyProperty(css.Background_Position, values[i:j])
|
|
if !hasSize && len(positionValues) == 2 && positionValues[0].TokenType == css.NumberToken && bytes.Equal(positionValues[0].Data, []byte("0")) && positionValues[0].Equal(positionValues[1]) {
|
|
values = append(values[:i], values[j:]...)
|
|
i--
|
|
} else {
|
|
values = append(values[:i], append(positionValues, values[j:]...)...)
|
|
i += len(positionValues) - 1
|
|
}
|
|
}
|
|
}
|
|
|
|
if len(values) == 0 {
|
|
values = []Token{{css.NumberToken, []byte("0"), nil}, {css.NumberToken, []byte("0"), nil}}
|
|
}
|
|
case css.Background_Size:
|
|
if len(values) == 2 && values[1].TokenType == css.IdentToken && bytes.Equal(values[1].Data, []byte("auto")) {
|
|
values = values[:1]
|
|
}
|
|
case css.Background_Repeat:
|
|
if len(values) == 2 && values[0].TokenType == css.IdentToken && values[1].TokenType == css.IdentToken {
|
|
h0 := css.ToHash(values[0].Data)
|
|
h1 := css.ToHash(values[1].Data)
|
|
if h0 == h1 {
|
|
values = values[:1]
|
|
} else if h0 == css.Repeat && h1 == css.No_Repeat {
|
|
values = values[:1]
|
|
values[0].Data = []byte("repeat-x")
|
|
} else if h0 == css.No_Repeat && h1 == css.Repeat {
|
|
values = values[:1]
|
|
values[0].Data = []byte("repeat-y")
|
|
}
|
|
}
|
|
case css.Background_Position:
|
|
if len(values) == 3 || len(values) == 4 {
|
|
// remove zero offsets
|
|
for _, i := range []int{len(values) - 1, 1} {
|
|
if 2 < len(values) && (values[i].TokenType == css.NumberToken && bytes.Equal(values[i].Data, []byte("0")) || values[i].TokenType == css.PercentageToken && bytes.Equal(values[i].Data, []byte("0%"))) {
|
|
values = append(values[:i], values[i+1:]...)
|
|
}
|
|
}
|
|
|
|
j := 1 // position of second set of horizontal/vertical values
|
|
if 2 < len(values) && values[2].TokenType == css.IdentToken {
|
|
j = 2
|
|
}
|
|
hs := make([]css.Hash, 3)
|
|
hs[0] = css.ToHash(values[0].Data)
|
|
hs[j] = css.ToHash(values[j].Data)
|
|
|
|
b := make([]byte, 0, 4)
|
|
offsets := make([]Token, 2)
|
|
for _, i := range []int{j, 0} {
|
|
if i+1 < len(values) && i+1 != j {
|
|
if values[i+1].TokenType == css.PercentageToken {
|
|
// change right or bottom with percentage offset to left or top respectively
|
|
if hs[i] == css.Right || hs[i] == css.Bottom {
|
|
n, _ := strconvParse.ParseInt(values[i+1].Data[:len(values[i+1].Data)-1])
|
|
b = strconv.AppendInt(b[:0], 100-n, 10)
|
|
b = append(b, '%')
|
|
values[i+1].Data = b
|
|
if hs[i] == css.Right {
|
|
values[i].Data = []byte("left")
|
|
hs[i] = css.Left
|
|
} else {
|
|
values[i].Data = []byte("top")
|
|
hs[i] = css.Top
|
|
}
|
|
}
|
|
}
|
|
if hs[i] == css.Left {
|
|
offsets[0] = values[i+1]
|
|
} else if hs[i] == css.Top {
|
|
offsets[1] = values[i+1]
|
|
}
|
|
} else if hs[i] == css.Left {
|
|
offsets[0] = Token{css.NumberToken, []byte("0"), nil}
|
|
} else if hs[i] == css.Top {
|
|
offsets[1] = Token{css.NumberToken, []byte("0"), nil}
|
|
} else if hs[i] == css.Right {
|
|
offsets[0] = Token{css.PercentageToken, []byte("100%"), nil}
|
|
hs[i] = css.Left
|
|
} else if hs[i] == css.Bottom {
|
|
offsets[1] = Token{css.PercentageToken, []byte("100%"), nil}
|
|
hs[i] = css.Top
|
|
}
|
|
}
|
|
|
|
if hs[0] == css.Center || hs[j] == css.Center {
|
|
if hs[0] == css.Left || hs[j] == css.Left {
|
|
offsets = offsets[:1]
|
|
} else if hs[0] == css.Top || hs[j] == css.Top {
|
|
offsets[0] = Token{css.NumberToken, []byte("50%"), nil}
|
|
}
|
|
}
|
|
|
|
if offsets[0].Data != nil && (len(offsets) == 1 || offsets[1].Data != nil) {
|
|
values = offsets
|
|
}
|
|
}
|
|
// removing zero offsets in the previous loop might make it eligible for the next loop
|
|
if len(values) == 1 || len(values) == 2 {
|
|
if values[0].TokenType == css.IdentToken {
|
|
h := css.ToHash(values[0].Data)
|
|
if h == css.Top || h == css.Bottom {
|
|
if len(values) == 1 {
|
|
// we can't make this smaller, and converting to a number will break it
|
|
// (https://github.com/tdewolff/minify/issues/221#issuecomment-415419918)
|
|
break
|
|
}
|
|
// if it's a vertical position keyword, swap it with the next element
|
|
// since otherwise converted number positions won't be valid anymore
|
|
// (https://github.com/tdewolff/minify/issues/221#issue-353067229)
|
|
values[0], values[1] = values[1], values[0]
|
|
}
|
|
}
|
|
// transform keywords to lengths|percentages
|
|
for i := 0; i < len(values); i++ {
|
|
if values[i].TokenType == css.IdentToken {
|
|
h := css.ToHash(values[i].Data)
|
|
if h == css.Left || h == css.Top {
|
|
values[i].TokenType = css.NumberToken
|
|
values[i].Data = []byte("0")
|
|
} else if h == css.Right || h == css.Bottom {
|
|
values[i].TokenType = css.PercentageToken
|
|
values[i].Data = []byte("100%")
|
|
} else if h == css.Center {
|
|
if i == 0 {
|
|
values[i].TokenType = css.PercentageToken
|
|
values[i].Data = []byte("50%")
|
|
} else {
|
|
values = values[:1]
|
|
}
|
|
}
|
|
} else if i == 1 && values[i].TokenType == css.PercentageToken && bytes.Equal(values[i].Data, []byte("50%")) {
|
|
values = values[:1]
|
|
} else if values[i].TokenType == css.PercentageToken && bytes.Equal(values[i].Data, []byte("0%")) {
|
|
values[i].TokenType = css.NumberToken
|
|
values[i].Data = []byte("0")
|
|
}
|
|
}
|
|
}
|
|
case css.Box_Shadow:
|
|
if len(values) == 4 && len(values[0].Data) == 1 && values[0].Data[0] == '0' && len(values[1].Data) == 1 && values[1].Data[0] == '0' && len(values[2].Data) == 1 && values[2].Data[0] == '0' && len(values[3].Data) == 1 && values[3].Data[0] == '0' {
|
|
values = values[:2]
|
|
}
|
|
case css.Ms_Filter:
|
|
alpha := []byte("progid:DXImageTransform.Microsoft.Alpha(Opacity=")
|
|
if values[0].TokenType == css.StringToken && 2 < len(values[0].Data) && bytes.HasPrefix(values[0].Data[1:len(values[0].Data)-1], alpha) {
|
|
values[0].Data = append(append([]byte{values[0].Data[0]}, []byte("alpha(opacity=")...), values[0].Data[1+len(alpha):]...)
|
|
}
|
|
}
|
|
return values
|
|
}
|
|
|
|
func (c *cssMinifier) minifyColorAsHex(rgba [3]byte) error {
|
|
val := make([]byte, 7)
|
|
val[0] = '#'
|
|
hex.Encode(val[1:], rgba[:])
|
|
parse.ToLower(val)
|
|
if s, ok := ShortenColorHex[string(val[:7])]; ok {
|
|
if _, err := c.w.Write(s); err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
} else if val[1] == val[2] && val[3] == val[4] && val[5] == val[6] {
|
|
val[2] = val[3]
|
|
val[3] = val[5]
|
|
val = val[:4]
|
|
} else {
|
|
val = val[:7]
|
|
}
|
|
|
|
_, err := c.w.Write(val)
|
|
return err
|
|
}
|
|
|
|
func (c *cssMinifier) minifyFunction(values []css.Token) error {
|
|
if n := len(values); n > 2 {
|
|
fun := css.ToHash(values[0].Data[0 : len(values[0].Data)-1])
|
|
if fun == css.Rgb || fun == css.Rgba || fun == css.Hsl || fun == css.Hsla {
|
|
valid := true
|
|
vals := make([]*css.Token, 0, 4)
|
|
for i, value := range values[1 : n-1] {
|
|
numeric := value.TokenType == css.NumberToken || value.TokenType == css.PercentageToken
|
|
separator := value.TokenType == css.CommaToken || i != 5 && value.TokenType == css.WhitespaceToken || i == 5 && value.TokenType == css.DelimToken && value.Data[0] == '/'
|
|
if i%2 == 0 && !numeric || i%2 == 1 && !separator {
|
|
valid = false
|
|
} else if numeric {
|
|
vals = append(vals, &values[i+1])
|
|
}
|
|
}
|
|
|
|
if valid {
|
|
for _, val := range vals {
|
|
val.TokenType, val.Data = c.shortenToken(0, val.TokenType, val.Data)
|
|
}
|
|
|
|
a := byte(255)
|
|
if len(vals) == 4 {
|
|
d, _ := strconv.ParseFloat(string(values[7].Data), 32) // can never fail because if valid == true than this is a NumberToken or PercentageToken
|
|
if d < minify.Epsilon { // zero or less
|
|
_, err := c.w.Write(transparentBytes)
|
|
return err
|
|
} else if d >= 1.0 {
|
|
values = values[:7]
|
|
} else {
|
|
a = byte(d*255.0 + 0.5)
|
|
}
|
|
}
|
|
|
|
if a == 255 { // only minify color if fully opaque
|
|
if (fun == css.Rgb || fun == css.Rgba) && (len(vals) == 3 || len(vals) == 4) {
|
|
rgb := [3]byte{}
|
|
|
|
for j, val := range vals[:3] {
|
|
if val.TokenType == css.NumberToken {
|
|
d, _ := strconv.ParseInt(string(val.Data), 10, 32)
|
|
if d < 0 {
|
|
d = 0
|
|
} else if d > 255 {
|
|
d = 255
|
|
}
|
|
rgb[j] = byte(d)
|
|
} else if val.TokenType == css.PercentageToken {
|
|
d, _ := strconv.ParseFloat(string(val.Data[:len(val.Data)-1]), 32)
|
|
if d < 0.0 {
|
|
d = 0.0
|
|
} else if d > 100.0 {
|
|
d = 100.0
|
|
}
|
|
rgb[j] = byte((d / 100.0 * 255.0) + 0.5)
|
|
}
|
|
}
|
|
return c.minifyColorAsHex(rgb)
|
|
} else if (fun == css.Hsl || fun == css.Hsla) && (len(vals) == 3 || len(vals) == 4) && vals[0].TokenType == css.NumberToken && vals[1].TokenType == css.PercentageToken && vals[2].TokenType == css.PercentageToken {
|
|
h, _ := strconv.ParseFloat(string(vals[0].Data), 32)
|
|
s, _ := strconv.ParseFloat(string(vals[1].Data[:len(vals[1].Data)-1]), 32)
|
|
l, _ := strconv.ParseFloat(string(vals[2].Data[:len(vals[2].Data)-1]), 32)
|
|
for h > 360.0 {
|
|
h -= 360.0
|
|
}
|
|
if s < 0.0 {
|
|
s = 0.0
|
|
} else if s > 100.0 {
|
|
s = 100.0
|
|
}
|
|
if l < 0.0 {
|
|
l = 0.0
|
|
} else if l > 100.0 {
|
|
l = 100.0
|
|
}
|
|
|
|
r, g, b := css.HSL2RGB(h/360.0, s/100.0, l/100.0)
|
|
rgb := [3]byte{byte((r * 255.0) + 0.5), byte((g * 255.0) + 0.5), byte((b * 255.0) + 0.5)}
|
|
return c.minifyColorAsHex(rgb)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
for _, value := range values {
|
|
if _, err := c.w.Write(value.Data); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (c *cssMinifier) shortenToken(prop css.Hash, tt css.TokenType, data []byte) (css.TokenType, []byte) {
|
|
switch tt {
|
|
case css.NumberToken, css.PercentageToken, css.DimensionToken:
|
|
if tt == css.NumberToken && (prop == css.Z_Index || prop == css.Counter_Increment || prop == css.Counter_Reset || prop == css.Orphans || prop == css.Widows) {
|
|
return tt, data // integers
|
|
}
|
|
n := len(data)
|
|
if tt == css.PercentageToken {
|
|
n--
|
|
} else if tt == css.DimensionToken {
|
|
n = parse.Number(data)
|
|
}
|
|
dim := data[n:]
|
|
parse.ToLower(dim)
|
|
if !c.o.KeepCSS2 {
|
|
data = minify.Number(data[:n], c.o.Decimals)
|
|
} else {
|
|
data = minify.Decimal(data[:n], c.o.Decimals) // don't use exponents
|
|
}
|
|
if tt == css.DimensionToken && (len(data) != 1 || data[0] != '0' || !optionalZeroDimension[string(dim)] || prop == css.Flex) {
|
|
data = append(data, dim...)
|
|
} else if tt == css.PercentageToken {
|
|
data = append(data, '%') // TODO: drop percentage for properties that accept <percentage> and <length>
|
|
}
|
|
case css.IdentToken:
|
|
parse.ToLower(parse.Copy(data)) // not all identifiers are case-insensitive; all <custom-ident> properties are case-sensitive
|
|
hash := css.ToHash(data)
|
|
if hexValue, ok := ShortenColorName[hash]; ok {
|
|
tt = css.HashToken
|
|
data = hexValue
|
|
}
|
|
case css.HashToken:
|
|
parse.ToLower(data)
|
|
if len(data) == 9 && data[7] == data[8] {
|
|
if data[7] == 'f' {
|
|
data = data[:7]
|
|
} else if data[7] == '0' {
|
|
data = []byte("#0000")
|
|
}
|
|
}
|
|
if ident, ok := ShortenColorHex[string(data)]; ok {
|
|
tt = css.IdentToken
|
|
data = ident
|
|
} else if len(data) == 7 && data[1] == data[2] && data[3] == data[4] && data[5] == data[6] {
|
|
tt = css.HashToken
|
|
data[2] = data[3]
|
|
data[3] = data[5]
|
|
data = data[:4]
|
|
} else if len(data) == 9 && data[1] == data[2] && data[3] == data[4] && data[5] == data[6] && data[7] == data[8] {
|
|
// from working draft Color Module Level 4
|
|
tt = css.HashToken
|
|
data[2] = data[3]
|
|
data[3] = data[5]
|
|
data[4] = data[7]
|
|
data = data[:5]
|
|
}
|
|
case css.StringToken:
|
|
data = removeStringNewlinex(data)
|
|
case css.URLToken:
|
|
parse.ToLower(data[:3])
|
|
if 10 < len(data) {
|
|
uri := parse.TrimWhitespace(data[4 : len(data)-1])
|
|
delim := byte('"')
|
|
if 1 < len(uri) && (uri[0] == '\'' || uri[0] == '"') {
|
|
delim = uri[0]
|
|
uri = removeStringNewlinex(uri)
|
|
uri = uri[1 : len(uri)-1]
|
|
}
|
|
uri = minify.DataURI(c.m, uri)
|
|
if css.IsURLUnquoted(uri) {
|
|
data = append(append([]byte("url("), uri...), ')')
|
|
} else {
|
|
data = append(append(append([]byte("url("), delim), uri...), delim, ')')
|
|
}
|
|
}
|
|
}
|
|
return tt, data
|
|
}
|
|
|
|
func removeStringNewlinex(data []byte) []byte {
|
|
// remove any \\\r\n \\\r \\\n
|
|
for i := 1; i < len(data)-2; i++ {
|
|
if data[i] == '\\' && (data[i+1] == '\n' || data[i+1] == '\r') {
|
|
// encountered first replacee, now start to move bytes to the front
|
|
j := i + 2
|
|
if data[i+1] == '\r' && len(data) > i+2 && data[i+2] == '\n' {
|
|
j++
|
|
}
|
|
for ; j < len(data); j++ {
|
|
if data[j] == '\\' && len(data) > j+1 && (data[j+1] == '\n' || data[j+1] == '\r') {
|
|
if data[j+1] == '\r' && len(data) > j+2 && data[j+2] == '\n' {
|
|
j++
|
|
}
|
|
j++
|
|
} else {
|
|
data[i] = data[j]
|
|
i++
|
|
}
|
|
}
|
|
data = data[:i]
|
|
break
|
|
}
|
|
}
|
|
return data
|
|
}
|