1// Copyright 2011 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package norm
6
7import "unicode/utf8"
8
9type input struct {
10	str   string
11	bytes []byte
12}
13
14func inputBytes(str []byte) input {
15	return input{bytes: str}
16}
17
18func inputString(str string) input {
19	return input{str: str}
20}
21
22func (in *input) setBytes(str []byte) {
23	in.str = ""
24	in.bytes = str
25}
26
27func (in *input) setString(str string) {
28	in.str = str
29	in.bytes = nil
30}
31
32func (in *input) _byte(p int) byte {
33	if in.bytes == nil {
34		return in.str[p]
35	}
36	return in.bytes[p]
37}
38
39func (in *input) skipASCII(p, max int) int {
40	if in.bytes == nil {
41		for ; p < max && in.str[p] < utf8.RuneSelf; p++ {
42		}
43	} else {
44		for ; p < max && in.bytes[p] < utf8.RuneSelf; p++ {
45		}
46	}
47	return p
48}
49
50func (in *input) skipContinuationBytes(p int) int {
51	if in.bytes == nil {
52		for ; p < len(in.str) && !utf8.RuneStart(in.str[p]); p++ {
53		}
54	} else {
55		for ; p < len(in.bytes) && !utf8.RuneStart(in.bytes[p]); p++ {
56		}
57	}
58	return p
59}
60
61func (in *input) appendSlice(buf []byte, b, e int) []byte {
62	if in.bytes != nil {
63		return append(buf, in.bytes[b:e]...)
64	}
65	for i := b; i < e; i++ {
66		buf = append(buf, in.str[i])
67	}
68	return buf
69}
70
71func (in *input) copySlice(buf []byte, b, e int) int {
72	if in.bytes == nil {
73		return copy(buf, in.str[b:e])
74	}
75	return copy(buf, in.bytes[b:e])
76}
77
78func (in *input) charinfoNFC(p int) (uint16, int) {
79	if in.bytes == nil {
80		return nfcData.lookupString(in.str[p:])
81	}
82	return nfcData.lookup(in.bytes[p:])
83}
84
85func (in *input) charinfoNFKC(p int) (uint16, int) {
86	if in.bytes == nil {
87		return nfkcData.lookupString(in.str[p:])
88	}
89	return nfkcData.lookup(in.bytes[p:])
90}
91
92func (in *input) hangul(p int) (r rune) {
93	var size int
94	if in.bytes == nil {
95		if !isHangulString(in.str[p:]) {
96			return 0
97		}
98		r, size = utf8.DecodeRuneInString(in.str[p:])
99	} else {
100		if !isHangul(in.bytes[p:]) {
101			return 0
102		}
103		r, size = utf8.DecodeRune(in.bytes[p:])
104	}
105	if size != hangulUTF8Size {
106		return 0
107	}
108	return r
109}
110