1 |
package gcss |
2 |
|
3 |
import ( |
4 |
"fmt" |
5 |
"strings" |
6 |
) |
7 |
|
8 |
const unicodeSpace = 32 |
9 |
|
10 |
const indentTop = 0 |
11 |
|
12 |
// line represents a line of codes. |
13 |
type line struct { |
14 |
no int |
15 |
s string |
16 |
indent int |
17 |
} |
18 |
|
19 |
// isEmpty returns true if the line's s is zero value. |
20 |
func (ln *line) isEmpty() bool { |
21 |
return strings.TrimSpace(ln.s) == "" |
22 |
} |
23 |
|
24 |
// isTopIndent returns true if the line's indent is the top level. |
25 |
func (ln *line) isTopIndent() bool { |
26 |
return ln.indent == indentTop |
27 |
} |
28 |
|
29 |
// childOf returns true if the line is a child of the parent. |
30 |
func (ln *line) childOf(parent element) (bool, error) { |
31 |
var ok bool |
32 |
var err error |
33 |
|
34 |
switch pIndent := parent.Base().ln.indent; { |
35 |
case ln.indent == pIndent+1: |
36 |
ok = true |
37 |
case ln.indent > pIndent+1: |
38 |
err = fmt.Errorf("indent is invalid [line: %d]", ln.no) |
39 |
} |
40 |
|
41 |
return ok, err |
42 |
} |
43 |
|
44 |
// isDeclaration returns true if the line is a declaration. |
45 |
func (ln *line) isDeclaration() bool { |
46 |
_, _, err := declarationPV(ln) |
47 |
return err == nil |
48 |
} |
49 |
|
50 |
// isAtRule returns true if the line is an at-rule. |
51 |
func (ln *line) isAtRule() bool { |
52 |
return strings.HasPrefix(strings.TrimSpace(ln.s), atMark) |
53 |
} |
54 |
|
55 |
// isVariable returns true if the line is a variable. |
56 |
func (ln *line) isVariable() bool { |
57 |
if !ln.isTopIndent() { |
58 |
return false |
59 |
} |
60 |
|
61 |
_, _, err := variableNV(ln) |
62 |
|
63 |
return err == nil |
64 |
} |
65 |
|
66 |
// isMixinDeclaration returns true if the line is a mixin declaration. |
67 |
func (ln *line) isMixinDeclaration() bool { |
68 |
if !ln.isTopIndent() { |
69 |
return false |
70 |
} |
71 |
|
72 |
_, _, err := mixinNP(ln, true) |
73 |
|
74 |
return err == nil |
75 |
} |
76 |
|
77 |
// isMixinInvocation returns true if the line is a mixin invocation. |
78 |
func (ln *line) isMixinInvocation() bool { |
79 |
if ln.isTopIndent() { |
80 |
return false |
81 |
} |
82 |
|
83 |
_, _, err := mixinNP(ln, false) |
84 |
|
85 |
return err == nil |
86 |
} |
87 |
|
88 |
// isComment returns true if the line is a comment. |
89 |
func (ln *line) isComment() bool { |
90 |
return strings.HasPrefix(strings.TrimSpace(ln.s), doubleSlash) |
91 |
} |
92 |
|
93 |
// newLine creates and returns a line. |
94 |
func newLine(no int, s string) *line { |
95 |
return &line{ |
96 |
no: no, |
97 |
s: s, |
98 |
indent: indent(s), |
99 |
} |
100 |
} |
101 |
|
102 |
// indent returns the string's indent. |
103 |
func indent(s string) int { |
104 |
var i int |
105 |
|
106 |
for _, b := range s { |
107 |
if b != unicodeSpace { |
108 |
break |
109 |
} |
110 |
i++ |
111 |
} |
112 |
|
113 |
return i / 2 |
114 |
} |