1 // Copyright 2014 The PDFium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6 // Original code is licensed as follows:
7 /*
8 * Copyright 2006-2007 Jeremias Maerki.
9 *
10 * Licensed under the Apache License, Version 2.0 (the "License");
11 * you may not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
13 *
14 * http://www.apache.org/licenses/LICENSE-2.0
15 *
16 * Unless required by applicable law or agreed to in writing, software
17 * distributed under the License is distributed on an "AS IS" BASIS,
18 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19 * See the License for the specific language governing permissions and
20 * limitations under the License.
21 */
22
23 #include "fxbarcode/datamatrix/BC_EdifactEncoder.h"
24
25 #include <algorithm>
26
27 #include "fxbarcode/datamatrix/BC_Encoder.h"
28 #include "fxbarcode/datamatrix/BC_EncoderContext.h"
29 #include "fxbarcode/datamatrix/BC_HighLevelEncoder.h"
30 #include "fxbarcode/datamatrix/BC_SymbolInfo.h"
31
32 namespace {
33
EncodeToEdifactCodewords(const WideString & sb)34 WideString EncodeToEdifactCodewords(const WideString& sb) {
35 size_t len = sb.GetLength();
36 if (len == 0)
37 return WideString();
38
39 wchar_t c1 = sb[0];
40 wchar_t c2 = len >= 2 ? sb[1] : 0;
41 wchar_t c3 = len >= 3 ? sb[2] : 0;
42 wchar_t c4 = len >= 4 ? sb[3] : 0;
43 int32_t v = (c1 << 18) + (c2 << 12) + (c3 << 6) + c4;
44 constexpr size_t kBuflen = 3;
45 wchar_t cw[kBuflen];
46 cw[0] = static_cast<wchar_t>((v >> 16) & 255);
47 cw[1] = static_cast<wchar_t>((v >> 8) & 255);
48 cw[2] = static_cast<wchar_t>(v & 255);
49 // TODO(tsepez): stop putting binary data in strings.
50 return WideString(
51 WideStringView(pdfium::make_span(cw).first(std::min(len, kBuflen))));
52 }
53
HandleEOD(CBC_EncoderContext * context,const WideString & buffer)54 bool HandleEOD(CBC_EncoderContext* context, const WideString& buffer) {
55 size_t count = buffer.GetLength();
56 if (count == 0)
57 return true;
58 if (count > 4)
59 return false;
60
61 if (count == 1) {
62 if (!context->UpdateSymbolInfo())
63 return false;
64
65 int32_t available =
66 context->m_symbolInfo->data_capacity() - context->getCodewordCount();
67 int32_t remaining = context->getRemainingCharacters();
68 if (remaining == 0 && available <= 2)
69 return true;
70 }
71
72 int32_t restChars = count - 1;
73 WideString encoded = EncodeToEdifactCodewords(buffer);
74 if (encoded.IsEmpty())
75 return false;
76
77 bool endOfSymbolReached = !context->hasMoreCharacters();
78 bool restInAscii = endOfSymbolReached && restChars <= 2;
79 if (restChars <= 2) {
80 if (!context->UpdateSymbolInfo(context->getCodewordCount() + restChars))
81 return false;
82
83 int32_t available =
84 context->m_symbolInfo->data_capacity() - context->getCodewordCount();
85 if (available >= 3) {
86 restInAscii = false;
87 if (!context->UpdateSymbolInfo(context->getCodewordCount() +
88 encoded.GetLength())) {
89 return false;
90 }
91 }
92 }
93
94 if (restInAscii) {
95 context->resetSymbolInfo();
96 context->m_pos -= restChars;
97 } else {
98 context->writeCodewords(encoded);
99 }
100 context->SignalEncoderChange(CBC_HighLevelEncoder::Encoding::ASCII);
101 return true;
102 }
103
AppendEncodedChar(wchar_t c,WideString * sb)104 bool AppendEncodedChar(wchar_t c, WideString* sb) {
105 if (c >= ' ' && c <= '?') {
106 *sb += c;
107 return true;
108 }
109
110 if (c >= '@' && c <= '^') {
111 *sb += (c - 64);
112 return true;
113 }
114
115 return false;
116 }
117
118 } // namespace
119
120 CBC_EdifactEncoder::CBC_EdifactEncoder() = default;
121
122 CBC_EdifactEncoder::~CBC_EdifactEncoder() = default;
123
GetEncodingMode()124 CBC_HighLevelEncoder::Encoding CBC_EdifactEncoder::GetEncodingMode() {
125 return CBC_HighLevelEncoder::Encoding::EDIFACT;
126 }
127
Encode(CBC_EncoderContext * context)128 bool CBC_EdifactEncoder::Encode(CBC_EncoderContext* context) {
129 WideString buffer;
130 while (context->hasMoreCharacters()) {
131 wchar_t c = context->getCurrentChar();
132 if (!AppendEncodedChar(c, &buffer))
133 return false;
134
135 context->m_pos++;
136 size_t count = buffer.GetLength();
137 if (count >= 4) {
138 WideString encoded = EncodeToEdifactCodewords(buffer);
139 if (encoded.IsEmpty())
140 return false;
141
142 context->writeCodewords(encoded);
143 buffer.Delete(0, 4);
144 CBC_HighLevelEncoder::Encoding newMode =
145 CBC_HighLevelEncoder::LookAheadTest(context->m_msg, context->m_pos,
146 GetEncodingMode());
147 if (newMode != GetEncodingMode()) {
148 context->SignalEncoderChange(CBC_HighLevelEncoder::Encoding::ASCII);
149 break;
150 }
151 }
152 }
153 buffer += static_cast<wchar_t>(31);
154 return HandleEOD(context, buffer);
155 }
156