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50
51#include "previewform.h"
52
53#include <QApplication>
54#include <QComboBox>
55#include <QDialogButtonBox>
56#include <QGridLayout>
57#include <QLabel>
58#include <QPlainTextEdit>
59#include <QPushButton>
60#include <QScreen>
61#include <QTextCodec>
62#include <QTextStream>
63
64// Helpers for creating hex dumps
65static void indent(QTextStream &str, int indent)
66{
67 for (int i = 0; i < indent; ++i)
68 str << ' ';
69}
70
71static void formatHex(QTextStream &str, const QByteArray &data)
72{
73 const int fieldWidth = str.fieldWidth();
74 const QTextStream::FieldAlignment alignment = str.fieldAlignment();
75 const int base = str.integerBase();
76 const QChar padChar = str.padChar();
77 str.setIntegerBase(16);
78 str.setPadChar(QLatin1Char('0'));
79 str.setFieldAlignment(QTextStream::AlignRight);
80
81 const unsigned char *p = reinterpret_cast<const unsigned char *>(data.constBegin());
82 for (const unsigned char *end = p + data.size(); p < end; ++p) {
83 str << ' ';
84 str.setFieldWidth(2);
85 str << unsigned(*p);
86 str.setFieldWidth(fieldWidth);
87 }
88 str.setFieldAlignment(alignment);
89 str.setPadChar(padChar);
90 str.setIntegerBase(base);
91}
92
93static void formatPrintableCharacters(QTextStream &str, const QByteArray &data)
94{
95 for (const char c : data) {
96 switch (c) {
97 case '\0':
98 str << "\\0";
99 break;
100 case '\t':
101 str << "\\t";
102 break;
103 case '\r':
104 str << "\\r";
105 break;
106 case '\n':
107 str << "\\n";
108 break;
109 default:
110 if (c >= 32 && uchar(c) < 127)
111 str << ' ' << c;
112 else
113 str << "..";
114 break;
115 }
116 }
117}
118
119static QString formatHexDump(const QByteArray &data)
120{
121 enum { lineWidth = 16 };
122 QString result;
123 QTextStream str(&result);
124 str.setIntegerBase(16);
125 str.setPadChar(QLatin1Char('0'));
126 const int fieldWidth = str.fieldWidth();
127 const QTextStream::FieldAlignment alignment = str.fieldAlignment();
128 for (int a = 0, size = data.size(); a < size; a += lineWidth) {
129 str.setFieldAlignment(QTextStream::AlignRight);
130 str.setFieldWidth(8);
131 str << a;
132 str.setFieldWidth(fieldWidth);
133 str.setFieldAlignment(alignment);
134
135 const int end = qMin(a: a + lineWidth, b: size);
136 const QByteArray line = data.mid(index: a, len: end - a);
137
138 formatHex(str, data: line);
139 indent(str, indent: 3 * (lineWidth - line.size()));
140
141 str << ' ';
142 formatPrintableCharacters(str, data: line);
143 indent(str, indent: 2 * (lineWidth - line.size()));
144 str << '\n';
145 }
146 return result;
147}
148
149PreviewForm::PreviewForm(QWidget *parent)
150 : QDialog(parent)
151{
152 setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
153 encodingComboBox = new QComboBox;
154
155 QLabel *encodingLabel = new QLabel(tr(s: "&Encoding:"));
156 encodingLabel->setBuddy(encodingComboBox);
157
158 textEdit = new QPlainTextEdit;
159 textEdit->setLineWrapMode(QPlainTextEdit::NoWrap);
160 textEdit->setReadOnly(true);
161 hexDumpEdit = new QPlainTextEdit;
162 hexDumpEdit->setLineWrapMode(QPlainTextEdit::NoWrap);
163 hexDumpEdit->setReadOnly(true);
164 hexDumpEdit->setFont(QFontDatabase::systemFont(type: QFontDatabase::FixedFont));
165
166 QDialogButtonBox *buttonBox =
167 new QDialogButtonBox(QDialogButtonBox::Ok | QDialogButtonBox::Cancel);
168 okButton = buttonBox->button(which: QDialogButtonBox::Ok);
169
170 connect(sender: encodingComboBox, signal: QOverload<int>::of(ptr: &QComboBox::activated),
171 receiver: this, slot: &PreviewForm::updateTextEdit);
172 connect(sender: buttonBox, signal: &QDialogButtonBox::accepted, receiver: this, slot: &QDialog::accept);
173 connect(sender: buttonBox, signal: &QDialogButtonBox::rejected, receiver: this, slot: &QDialog::reject);
174
175 QGridLayout *mainLayout = new QGridLayout(this);
176 mainLayout->addWidget(encodingLabel, row: 0, column: 0);
177 mainLayout->addWidget(encodingComboBox, row: 0, column: 1);
178 tabWidget = new QTabWidget;
179 tabWidget->addTab(widget: textEdit, tr(s: "Preview"));
180 tabWidget->addTab(widget: hexDumpEdit, tr(s: "Hex Dump"));
181 mainLayout->addWidget(tabWidget, row: 1, column: 0, rowSpan: 1, columnSpan: 2);
182 statusLabel = new QLabel;
183 mainLayout->addWidget(statusLabel, row: 2, column: 0, rowSpan: 1, columnSpan: 2);
184 mainLayout->addWidget(buttonBox, row: 3, column: 0, rowSpan: 1, columnSpan: 2);
185
186 const QRect screenGeometry = screen()->geometry();
187 resize(w: screenGeometry.width() * 2 / 5, h: screenGeometry.height() / 2);
188}
189
190void PreviewForm::setCodecList(const QVector<QTextCodec *> &list)
191{
192 encodingComboBox->clear();
193 for (const QTextCodec *codec : list) {
194 encodingComboBox->addItem(atext: QLatin1String(codec->name()),
195 auserData: QVariant(codec->mibEnum()));
196 }
197}
198
199void PreviewForm::reset()
200{
201 decodedStr.clear();
202 textEdit->clear();
203 hexDumpEdit->clear();
204 statusLabel->clear();
205 statusLabel->setStyleSheet(QString());
206 okButton->setEnabled(false);
207 tabWidget->setCurrentIndex(0);
208}
209
210void PreviewForm::setEncodedData(const QByteArray &data)
211{
212 reset();
213 encodedData = data;
214 hexDumpEdit->setPlainText(formatHexDump(data));
215 updateTextEdit();
216}
217
218void PreviewForm::updateTextEdit()
219{
220 int mib = encodingComboBox->itemData(
221 index: encodingComboBox->currentIndex()).toInt();
222 const QTextCodec *codec = QTextCodec::codecForMib(mib);
223 const QString name = QLatin1String(codec->name());
224
225 QTextCodec::ConverterState state;
226 decodedStr = codec->toUnicode(in: encodedData.constData(), length: encodedData.size(), state: &state);
227
228 bool success = true;
229 if (state.remainingChars) {
230 success = false;
231 const QString message =
232 tr(s: "%1: conversion error at character %2")
233 .arg(a: name).arg(a: encodedData.size() - state.remainingChars + 1);
234 statusLabel->setText(message);
235 statusLabel->setStyleSheet(QStringLiteral("background-color: \"red\";"));
236 } else if (state.invalidChars) {
237 statusLabel->setText(tr(s: "%1: %n invalid characters", c: nullptr, n: state.invalidChars).arg(a: name));
238 statusLabel->setStyleSheet(QStringLiteral("background-color: \"yellow\";"));
239 } else {
240 statusLabel->setText(tr(s: "%1: %n bytes converted", c: nullptr, n: encodedData.size()).arg(a: name));
241 statusLabel->setStyleSheet(QString());
242 }
243 if (success)
244 textEdit->setPlainText(decodedStr);
245 else
246 textEdit->clear();
247 okButton->setEnabled(success);
248}
249

source code of qtbase/examples/widgets/tools/codecs/previewform.cpp