GARbro-mirror/GUI/TextViewer.xaml.cs

242 lines
8.1 KiB
C#

//! \file TextViewer.cs
//! \date Mon May 11 23:24:33 2015
//! \brief Text file viewer widget.
//
// Copyright (C) 2015 by morkt
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//
using System;
using System.IO;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Media;
namespace JustView
{
/// <summary>
/// Interaction logic for TextViewer.xaml
/// </summary>
public partial class TextViewer : FlowDocumentScrollViewer
{
Lazy<double> m_default_width;
public TextViewer ()
{
m_default_width = new Lazy<double> (() => GetFixedWidth (80));
InitializeComponent();
DefaultZoom = 100;
}
public void Clear ()
{
this.Document.Blocks.Clear();
Input = null;
}
public ScrollViewer ScrollViewer { get { return FindScrollViewer(); } }
public double DefaultWidth { get { return m_default_width.Value; } }
public double DefaultZoom { get; private set; }
public Stream Input { get; set; }
public double MaxLineWidth { get; set; }
private bool m_word_wrap;
public bool IsWordWrapEnabled
{
get { return m_word_wrap; }
set
{
m_word_wrap = value;
if (Input != null)
ApplyWordWrap (value);
}
}
private Encoding m_current_encoding;
public Encoding CurrentEncoding
{
get { return m_current_encoding; }
set
{
if (m_current_encoding != value)
{
m_current_encoding = value;
Refresh();
}
}
}
public void DisplayStream (Stream file, Encoding enc)
{
if (file.Length > 0xffffff)
throw new ApplicationException ("File is too long");
ReadStream (file, enc);
var sv = FindScrollViewer();
if (sv != null)
sv.ScrollToHome();
Input = file;
m_current_encoding = enc;
}
public void Refresh ()
{
if (Input != null)
{
Input.Position = 0;
ReadStream (Input, CurrentEncoding);
}
}
byte[] m_test_buf = new byte[0x400];
public Encoding GuessEncoding (Stream file)
{
var enc = Encoding.Default;
if (3 == file.Read (m_test_buf, 0, 3))
{
if (IsUTF8())
enc = Encoding.UTF8;
else if (IsUTF16BE())
enc = Encoding.BigEndianUnicode;
else if (IsUTF16LE())
enc = Encoding.Unicode;
}
file.Position = 0;
return enc;
}
private bool IsUTF8 ()
{
return 0xEF == m_test_buf[0] && 0xBB == m_test_buf[1] && 0xBF == m_test_buf[2];
}
private bool IsUTF16BE ()
{
return 0xFE == m_test_buf[0] && 0xFF == m_test_buf[1];
}
private bool IsUTF16LE ()
{
return 0xFF == m_test_buf[0] && 0xFE == m_test_buf[1];
}
public bool IsTextFile (Stream file)
{
int read = file.Read (m_test_buf, 0, m_test_buf.Length);
file.Position = 0;
if (read > 3 && (IsUTF8() || IsUTF16LE() || IsUTF16BE()))
return true;
bool found_eol = false;
for (int i = 0; i < read; ++i)
{
byte c = m_test_buf[i];
if (c < 9 || (c > 0x0d && c < 0x1a) || (c > 0x1b && c < 0x20))
return false;
found_eol = found_eol || 0x0A == c;
}
return found_eol || read < 80;
}
double GetFixedWidth (int char_width)
{
var block = new TextBlock();
block.FontFamily = this.Document.FontFamily;
block.FontSize = this.Document.FontSize;
block.Padding = this.Document.PagePadding;
block.Text = new string ('M', char_width);
block.Measure (new Size (double.PositiveInfinity, double.PositiveInfinity));
return block.DesiredSize.Width;
}
void ReadStream (Stream file, Encoding enc)
{
using (var reader = new StreamReader (file, enc, false, 0x400, true))
{
this.Document.Blocks.Clear();
var para = new Paragraph();
var block = new TextBlock();
block.FontFamily = this.Document.FontFamily;
block.FontSize = this.Document.FontSize;
block.Padding = this.Document.PagePadding;
double max_width = 0;
var max_size = new Size (double.PositiveInfinity, double.PositiveInfinity);
for (;;)
{
var line = reader.ReadLine();
if (null == line)
break;
if (line.Length > 0)
{
block.Text = line;
block.Measure (max_size);
var width = block.DesiredSize.Width;
if (width > max_width)
max_width = width;
para.Inlines.Add (new Run (line));
}
para.Inlines.Add (new LineBreak());
}
this.Document.Blocks.Add (para);
MaxLineWidth = max_width;
ApplyWordWrap (IsWordWrapEnabled);
}
}
public void ApplyWordWrap (bool word_wrap)
{
var scroll = this.ScrollViewer;
if (word_wrap && scroll != null)
{
this.Document.PageWidth = scroll.ViewportWidth;
var width_binding = new Binding ("ViewportWidth");
width_binding.Source = scroll;
width_binding.Mode = BindingMode.OneWay;
width_binding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
BindingOperations.SetBinding (this.Document, FlowDocument.PageWidthProperty, width_binding);
}
else
{
BindingOperations.ClearBinding (this.Document, FlowDocument.PageWidthProperty);
this.Document.PageWidth = MaxLineWidth;
}
}
private ScrollViewer FindScrollViewer ()
{
if (VisualTreeHelper.GetChildrenCount (this) == 0)
return null;
// Border is the first child of first child of a ScrolldocumentViewer
var firstChild = VisualTreeHelper.GetChild (this, 0);
if (firstChild == null)
return null;
var border = VisualTreeHelper.GetChild (firstChild, 0) as Decorator;
if (border == null)
return null;
return border.Child as ScrollViewer;
}
}
}