summaryrefslogtreecommitdiffstats
path: root/kioslave/thumbnail/textcreator.cpp
blob: 31f4c4254a6442eb0ffd8f9dbc0bd8439028657b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
/*  This file is part of the KDE libraries
    Copyright (C) 2000,2002 Carsten Pfeiffer <pfeiffer@kde.org>
                  2000 Malte Starostik <malte@kde.org>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/

#include <tqfile.h>
#include <tqpixmap.h>
#include <tqimage.h>

#include <kstandarddirs.h>
#include <kpixmapsplitter.h>
#include <kmimetype.h>

#include "textcreator.h"

extern "C"
{
    KDE_EXPORT ThumbCreator *new_creator()
    {
        return new TextCreator;
    }
}

TextCreator::TextCreator()
    : m_splitter(0),
      m_data(0),
      m_dataSize(0)
{
}

TextCreator::~TextCreator()
{
    delete m_splitter;
    delete [] m_data;
}

bool TextCreator::create(const TQString &path, int width, int height, TQImage &img)
{
    // Filter out unwanted mimetypes
    KMimeType::Ptr mimeType = KMimeType::findByPath( path );
    if ( mimeType->is( "text/rtf" ) )
        return false;

    if ( !m_splitter )
    {
        m_splitter = new KPixmapSplitter;
        TQString pixmap = locate( "data", "konqueror/pics/thumbnailfont_7x4.png" );
        if ( !pixmap.isEmpty() )
        {
            // FIXME: make font/glyphsize configurable...
            m_splitter->setPixmap( TQPixmap( pixmap ));
            m_splitter->setItemSize( TQSize( 4, 7 ));
        }
    }

    bool ok = false;

    // determine some sizes...
    // example: width: 60, height: 64
    TQSize pixmapSize( width, height );
    if (height * 3 > width * 4)
        pixmapSize.setHeight( width * 4 / 3 );
    else
        pixmapSize.setWidth( height * 3 / 4 );

    if ( pixmapSize != m_pixmap.size() )
        m_pixmap.resize( pixmapSize );
    
    // one pixel for the rectangle, the rest. whitespace
    int xborder = 1 + pixmapSize.width()/16;  // minimum x-border
    int yborder = 1 + pixmapSize.height()/16; // minimum y-border

    TQSize chSize = m_splitter->itemSize(); // the size of one char
    int xOffset = chSize.width();
    int yOffset = chSize.height();

    // calculate a better border so that the text is centered
    int canvasWidth  = pixmapSize.width()  - 2*xborder;
    int canvasHeight = pixmapSize.height() -  2*yborder;
    int numCharsPerLine = (int) (canvasWidth / chSize.width());
    int numLines = (int) (canvasHeight / chSize.height());

    // assumes an average line length of <= 120 chars
    const int bytesToRead = 120 * numLines;

    // create text-preview
    TQFile file( path );
    if ( file.open( IO_ReadOnly ))
    {
        if ( !m_data || m_dataSize < bytesToRead + 1 )
        {
            delete [] m_data;
            m_data = new char[bytesToRead+1];
            m_dataSize = bytesToRead + 1;
        }

        int read = file.readBlock( m_data, bytesToRead );
        if ( read > 0 )
        {
            ok = true;
            m_data[read] = '\0';
            TQString text = TQString::fromLocal8Bit( m_data );
            // FIXME: maybe strip whitespace and read more?

            m_pixmap.fill( TQColor( 245, 245, 245 ) ); // light-grey background

            TQRect rect;

            int rest = m_pixmap.width() - (numCharsPerLine * chSize.width());
            xborder = QMAX( xborder, rest/2); // center horizontally
            rest = m_pixmap.height() - (numLines * chSize.height());
            yborder = QMAX( yborder, rest/2); // center vertically
            // end centering

            int x = xborder, y = yborder; // where to paint the characters
            int posNewLine  = m_pixmap.width() - (chSize.width() + xborder);
            int posLastLine = m_pixmap.height() - (chSize.height() + yborder);
            bool newLine = false;
            Q_ASSERT( posNewLine > 0 );
            const TQPixmap *fontPixmap = &(m_splitter->pixmap());

            for ( uint i = 0; i < text.length(); i++ )
            {
                if ( x > posNewLine || newLine ) // start a new line?
                {
                    x = xborder;
                    y += yOffset;

                    if ( y > posLastLine ) // more text than space
                        break;

                    // after starting a new line, we also jump to the next
                    // physical newline in the file if we don't come from one
                    if ( !newLine )
                    {
                        int pos = text.find( '\n', i );
                        if ( pos == -1 )
			    break;
                        i = pos + 1;
                    }

                    newLine = false;
                }

                // check for newlines in the text (unix,dos)
                TQChar ch = text.at( i );
                if ( ch == '\n' )
                {
                    newLine = true;
                    continue;
                }
                else if ( ch == '\r' && text.at(i+1) == '\n' )
                {
                    newLine = true;
                    i++; // skip the next character (\n) as well
                    continue;
                }

                rect = m_splitter->coordinates( ch );
                if ( !rect.isEmpty() )
                {
                    bitBlt( &m_pixmap, TQPoint(x,y), fontPixmap, rect, Qt::CopyROP );
                }

                x += xOffset; // next character
            }
            if (ok)
                img = m_pixmap.convertToImage();
        }

        file.close();
    }
    return ok;
}

ThumbCreator::Flags TextCreator::flags() const
{
    return (Flags)(DrawFrame | BlendIcon);
}