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#include "q3textedit.h"

#ifndef QT_NO_TEXTEDIT

#include <private/q3richtext_p.h>

#include "qpainter.h"

#include "qpen.h"

#include "qbrush.h"

#include "qpixmap.h"

#include "qfont.h"

#include "qcolor.h"

#include "qstyle.h"

#include "qsize.h"

#include "qevent.h"

#include "qtimer.h"

#include "qapplication.h"

#include "q3listbox.h"

#include "qclipboard.h"

#include "qcolordialog.h"

#include "q3stylesheet.h"

#include "q3dragobject.h"

#include "qurl.h"

#include "qcursor.h"

#include "qregexp.h"

#include "q3popupmenu.h"

#include "qstack.h"

#include "qmetaobject.h"

#include "q3textbrowser.h"

#include "private/q3syntaxhighlighter_p.h"

#include "qtextformat.h"

#ifndef QT_NO_IM

#include <qinputcontext.h>

#endif

#ifndef QT_NO_ACCEL

#include <qkeysequence.h>

#define ACCEL_KEY(k) QLatin1Char('\t') + QString(QKeySequence(Qt::CTRL | Qt::Key_ ## k))

#else

#define ACCEL_KEY(k) QLatin1Char('\t' )+ QString::fromLatin1("Ctrl+" #k)

#endif

#ifdef QT_TEXTEDIT_OPTIMIZATION

#define LOGOFFSET(i) d->logOffset + i

#endif

QT_BEGIN_NAMESPACE

struct QUndoRedoInfoPrivate

{

    Q3TextString text;

};

class Q3TextEditPrivate

{

public:

    Q3TextEditPrivate()

        :preeditStart(-1),preeditLength(-1),numPreeditSelections(0),ensureCursorVisibleInShowEvent(false),

         tabChangesFocus(false),

#ifndef QT_NO_CLIPBOARD

         clipboard_mode(QClipboard::Clipboard),

#endif

#ifdef QT_TEXTEDIT_OPTIMIZATION

         od(0), optimMode(false),

         maxLogLines(-1),

         logOffset(0),

#endif

         autoFormatting((uint)Q3TextEdit::AutoAll),

         cursorRepaintMode(false),

         cursorBlinkActive(false)

    {

        for (int i=0; i<7; i++)

            id[i] = 0;

    }

    int id[7];

    int preeditStart;

    int preeditLength;

    int numPreeditSelections;

    uint ensureCursorVisibleInShowEvent : 1;

    uint tabChangesFocus : 1;

    QString scrollToAnchor; // used to deferr scrollToAnchor() until the show event when we are resized

    QString pressedName;

    QString onName;

#ifndef QT_NO_CLIPBOARD

    QClipboard::Mode clipboard_mode;

#endif

    QTimer *trippleClickTimer;

    QPoint trippleClickPoint;

#ifdef QT_TEXTEDIT_OPTIMIZATION

    Q3TextEditOptimPrivate * od;

    bool optimMode : 1;

    int maxLogLines;

    int logOffset;

#endif

    Q3TextEdit::AutoFormatting autoFormatting;

    uint cursorRepaintMode : 1;

    uint cursorBlinkActive : 1;

};

#ifndef QT_NO_MIME

class Q3RichTextDrag : public Q3TextDrag

{

public:

    Q3RichTextDrag(QWidget *dragSource = 0, const char *name = 0);

    void setPlainText(const QString &txt) { setText(txt); }

    void setRichText(const QString &txt) { richTxt = txt; }

    virtual QByteArray encodedData(const char *mime) const;

    virtual const char* format(int i) const;

    static bool decode(QMimeSource *e, QString &str, const QString &mimetype,

                        const QString &subtype);

    static bool canDecode(QMimeSource* e);

private:

    QString richTxt;

};

Q3RichTextDrag::Q3RichTextDrag(QWidget *dragSource, const char *name)

    : Q3TextDrag(dragSource, name)

{

}

QByteArray Q3RichTextDrag::encodedData(const char *mime) const

{

    if (qstrcmp("application/x-qrichtext", mime) == 0) {

        return richTxt.toUtf8(); // #### perhaps we should use USC2 instead?

    } else

        return Q3TextDrag::encodedData(mime);

}

bool Q3RichTextDrag::decode(QMimeSource *e, QString &str, const QString &mimetype,

                            const QString &subtype)

{

    if (mimetype == QLatin1String("application/x-qrichtext")) {

        // do richtext decode

        const char *mime;

        int i;

        for (i = 0; (mime = e->format(i)); ++i) {

            if (qstrcmp("application/x-qrichtext", mime) != 0)

                continue;

            str = QString::fromUtf8(e->encodedData(mime));

            return true;

        }

        return false;

    }

    // do a regular text decode

    QString st = subtype;

    return Q3TextDrag::decode(e, str, st);

}

bool Q3RichTextDrag::canDecode(QMimeSource* e)

{

    if (e->provides("application/x-qrichtext"))

        return true;

    return Q3TextDrag::canDecode(e);

}

const char* Q3RichTextDrag::format(int i) const

{

    if (Q3TextDrag::format(i))

        return Q3TextDrag::format(i);

    if (Q3TextDrag::format(i-1))

        return "application/x-qrichtext";

    return 0;

}

#endif

static bool block_set_alignment = false;

/*!

    \class Q3TextEdit

    \brief The Q3TextEdit widget provides a powerful single-page rich text editor.

    \compat

    \tableofcontents

    \section1 Introduction and Concepts

    Q3TextEdit is an advanced WYSIWYG viewer/editor supporting rich

    text formatting using HTML-style tags. It is optimized to handle

    large documents and to respond quickly to user input.

    Q3TextEdit has four modes of operation:

    \table

    \header \i Mode \i Command \i Notes

    \row \i Plain Text Editor \i setTextFormat(Qt::PlainText)

         \i Set text with setText(); text() returns plain text. Text

         attributes (e.g. colors) can be set, but plain text is always

         returned.

    \row \i Rich Text Editor \i setTextFormat(Qt::RichText)

         \i Set text with setText(); text() returns rich text. Rich

         text editing is fairly limited. You can't set margins or

         insert images for example (although you can read and

         correctly display files that have margins set and that

         include images). This mode is mostly useful for editing small

         amounts of rich text.

    \row \i Text Viewer \i setReadOnly(true)

         \i Set text with setText() or append() (which has no undo

         history so is faster and uses less memory); text() returns

         plain or rich text depending on the textFormat(). This mode

         can correctly display a large subset of HTML tags.

    \row \i Log Viewer \i setTextFormat(Qt::LogText)

         \i Append text using append(). The widget is set to be read

         only and rich text support is disabled although a few HTML

         tags (for color, bold, italic and underline) may be used.

         (See \link #logtextmode Qt::LogText mode\endlink for details.)

    \endtable

    Q3TextEdit can be used as a syntax highlighting editor when used in

    conjunction with QSyntaxHighlighter.

    We recommend that you always call setTextFormat() to set the mode

    you want to use. If you use Qt::AutoText then setText() and

    append() will try to determine whether the text they are given is

    plain text or rich text. If you use Qt::RichText then setText() and

    append() will assume that the text they are given is rich text.

    insert() simply inserts the text it is given.

    Q3TextEdit works on paragraphs and characters. A paragraph is a

    formatted string which is word-wrapped to fit into the width of

    the widget. By default when reading plain text, one newline

    signify a paragraph. A document consists of zero or more

    paragraphs, indexed from 0. Characters are indexed on a

    per-paragraph basis, also indexed from 0. The words in the

    paragraph are aligned in accordance with the paragraph's

    alignment(). Paragraphs are separated by hard line breaks. Each

    character within a paragraph has its own attributes, for example,

    font and color.

    The text edit documentation uses the following concepts:

    \list

    \i \e{current format} --

    this is the format at the current cursor position, \e and it

    is the format of the selected text if any.

    \i \e{current paragraph} -- the paragraph which contains the

    cursor.

    \endlist

    Q3TextEdit can display images (using Q3MimeSourceFactory), lists and

    tables. If the text is too large to view within the text edit's

    viewport, scroll bars will appear. The text edit can load both

    plain text and HTML files (a subset of HTML 3.2 and 4). The

    rendering style and the set of valid tags are defined by a

    styleSheet(). Custom tags can be created and placed in a custom

    style sheet. Change the style sheet with \l{setStyleSheet()}; see

    Q3StyleSheet for details. The images identified by image tags are

    displayed if they can be interpreted using the text edit's

    \l{Q3MimeSourceFactory}; see setMimeSourceFactory().

    If you want a text browser with more navigation use QTextBrowser.

    If you just need to display a small piece of rich text use QLabel

    or QSimpleRichText.

    If you create a new Q3TextEdit, and want to allow the user to edit

    rich text, call setTextFormat(Qt::RichText) to ensure that the

    text is treated as rich text. (Rich text uses HTML tags to set

    text formatting attributes. See Q3StyleSheet for information on the

    HTML tags that are supported.). If you don't call setTextFormat()

    explicitly the text edit will guess from the text itself whether

    it is rich text or plain text. This means that if the text looks

    like HTML or XML it will probably be interpreted as rich text, so

    you should call setTextFormat(Qt::PlainText) to preserve such

    text.

    Note that we do not intend to add a full-featured web browser

    widget to Qt (because that would easily double Qt's size and only

    a few applications would benefit from it). The rich

    text support in Qt is designed to provide a fast, portable and

    efficient way to add reasonable online help facilities to

    applications, and to provide a basis for rich text editors.

    \section1 Using Q3TextEdit as a Display Widget

    Q3TextEdit can display a large HTML subset, including tables and

    images.

    The text is set or replaced using setText() which deletes any

    existing text and replaces it with the text passed in the

    setText() call. If you call setText() with legacy HTML (with

    setTextFormat(Qt::RichText) in force), and then call text(), the text

    that is returned may have different markup, but will render the

    same. Text can be inserted with insert(), paste(), pasteSubType()

    and append(). Text that is appended does not go into the undo

    history; this makes append() faster and consumes less memory. Text

    can also be cut(). The entire text is deleted with clear() and the

    selected text is deleted with removeSelectedText(). Selected

    (marked) text can also be deleted with del() (which will delete

    the character to the right of the cursor if no text is selected).

    Loading and saving text is achieved using setText() and text(),

    for example:

    \snippet doc/src/snippets/code/src_qt3support_text_q3textedit.cpp 0

    By default the text edit wraps words at whitespace to fit within

    the text edit widget. The setWordWrap() function is used to

    specify the kind of word wrap you want, or \c NoWrap if you don't

    want any wrapping. Call setWordWrap() to set a fixed pixel width

    \c FixedPixelWidth, or character column (e.g. 80 column) \c

    FixedColumnWidth with the pixels or columns specified with

    setWrapColumnOrWidth(). If you use word wrap to the widget's width

    \c WidgetWidth, you can specify whether to break on whitespace or

    anywhere with setWrapPolicy().

    The background color is set differently than other widgets, using

    setPaper(). You specify a brush style which could be a plain color

    or a complex pixmap.

    Hypertext links are automatically underlined; this can be changed

    with setLinkUnderline(). The tab stop width is set with

    setTabStopWidth().

    The zoomIn() and zoomOut() functions can be used to resize the

    text by increasing (decreasing for zoomOut()) the point size used.

    Images are not affected by the zoom functions.

    The lines() function returns the number of lines in the text and

    paragraphs() returns the number of paragraphs. The number of lines

    within a particular paragraph is returned by linesOfParagraph().

    The length of the entire text in characters is returned by

    length().

    You can scroll to an anchor in the text, e.g.

    \c{<a name="anchor">} with scrollToAnchor(). The find() function

    can be used to find and select a given string within the text.

    A read-only Q3TextEdit provides the same functionality as the

    (obsolete) QTextView. (QTextView is still supplied for

    compatibility with old code.)

    \section2 Read-only key bindings

    When Q3TextEdit is used read-only the key-bindings are limited to

    navigation, and text may only be selected with the mouse:

    \table

    \header \i Keypresses \i Action

    \row \i Up        \i Move one line up

    \row \i Down        \i Move one line down

    \row \i Left        \i Move one character left

    \row \i Right        \i Move one character right

    \row \i PageUp        \i Move one (viewport) page up

    \row \i PageDown        \i Move one (viewport) page down

    \row \i Home        \i Move to the beginning of the text

    \row \i End                \i Move to the end of the text

    \row \i Shift+Wheel

         \i Scroll the page horizontally (the Wheel is the mouse wheel)

    \row \i Ctrl+Wheel        \i Zoom the text

    \endtable

    The text edit may be able to provide some meta-information. For

    example, the documentTitle() function will return the text from

    within HTML \c{<title>} tags.

    The text displayed in a text edit has a \e context. The context is

    a path which the text edit's Q3MimeSourceFactory uses to resolve

    the locations of files and images. It is passed to the

    mimeSourceFactory() when quering data. (See Q3TextEdit() and

    \l{context()}.)

    \target logtextmode

    \section2 Using Q3TextEdit in Qt::LogText Mode

    Setting the text format to Qt::LogText puts the widget in a special

    mode which is optimized for very large texts. In this mode editing

    and rich text support are disabled (the widget is explicitly set

    to read-only mode). This allows the text to be stored in a

    different, more memory efficient manner. However, a certain degree

    of text formatting is supported through the use of formatting

    tags. A tag is delimited by \c < and \c {>}. The characters \c

    {<}, \c > and \c & are escaped by using \c {&lt;}, \c {&gt;} and

    \c {&}. A tag pair consists of a left and a right tag (or

    open/close tags). Left-tags mark the starting point for

    formatting, while right-tags mark the ending point. A right-tag

    always start with a \c / before the tag keyword. For example \c

    <b> and \c </b> are a tag pair. Tags can be nested, but they

    have to be closed in the same order as they are opened. For

    example, \c <b><u></u></b> is valid, while \c

    <b><u></b></u> will output an error message.

    By using tags it is possible to change the color, bold, italic and

    underline settings for a piece of text. A color can be specified

    by using the HTML font tag \c {<font color=colorname>}. The color

    name can be one of the color names from the X11 color database, or

    a RGB hex value (e.g \c {#00ff00}). Example of valid color tags:

    \c {<font color=red>}, \c{<font color="light blue">},\c {<font

    color="#223344">}. Bold, italic and underline settings can be

    specified by the tags \c {<b>}, \c <i> and \c {<u>}. Note that a

    tag does not necessarily have to be closed. A valid example:

    \snippet doc/src/snippets/code/src_qt3support_text_q3textedit.cpp 1

    Stylesheets can also be used in Qt::LogText mode. To create and use a

    custom tag, you could do the following:

    \snippet doc/src/snippets/code/src_qt3support_text_q3textedit.cpp 2

    Note that only the color, bold, underline and italic attributes of

    a Q3StyleSheetItem is used in Qt::LogText mode.

    Note that you can use setMaxLogLines() to limit the number of

    lines the widget can hold in Qt::LogText mode.

    There are a few things that you need to be aware of when the

    widget is in this mode:

    \list

    \i Functions that deal with rich text formatting and cursor

    movement will not work or return anything valid.

    \i Lines are equivalent to paragraphs.

    \endlist

    \section1 Using Q3TextEdit as an Editor

    All the information about using Q3TextEdit as a display widget also

    applies here.

    The current format's attributes are set with setItalic(),

    setBold(), setUnderline(), setFamily() (font family),

    setPointSize(), setColor() and setCurrentFont(). The current

    paragraph's alignment is set with setAlignment().

    Use setSelection() to select text. The setSelectionAttributes()

    function is used to indicate how selected text should be

    displayed. Use hasSelectedText() to find out if any text is

    selected. The currently selected text's position is available

    using getSelection() and the selected text itself is returned by

    selectedText(). The selection can be copied to the clipboard with

    copy(), or cut to the clipboard with cut(). It can be deleted with

    removeSelectedText(). The entire text can be selected (or

    unselected) using selectAll(). Q3TextEdit supports multiple

    selections. Most of the selection functions operate on the default

    selection, selection 0. If the user presses a non-selecting key,

    e.g. a cursor key without also holding down Shift, all selections

    are cleared.

    Set and get the position of the cursor with setCursorPosition()

    and getCursorPosition() respectively. When the cursor is moved,

    the signals currentFontChanged(), currentColorChanged() and

    currentAlignmentChanged() are emitted to reflect the font, color

    and alignment at the new cursor position.

    If the text changes, the textChanged() signal is emitted, and if

    the user inserts a new line by pressing Return or Enter,

    returnPressed() is emitted. The isModified() function will return

    true if the text has been modified.

    Q3TextEdit provides command-based undo and redo. To set the depth

    of the command history use setUndoDepth() which defaults to 100

    steps. To undo or redo the last operation call undo() or redo().

    The signals undoAvailable() and redoAvailable() indicate whether

    the undo and redo operations can be executed.

    \section2 Editing key bindings

    The list of key-bindings which are implemented for editing:

    \table

    \header \i Keypresses \i Action

    \row \i Backspace \i Delete the character to the left of the cursor

    \row \i Delete \i Delete the character to the right of the cursor

    \row \i Ctrl+A \i Move the cursor to the beginning of the line

    \row \i Ctrl+B \i Move the cursor one character left

    \row \i Ctrl+C \i Copy the marked text to the clipboard (also

                      Ctrl+Insert under Windows)

    \row \i Ctrl+D \i Delete the character to the right of the cursor

    \row \i Ctrl+E \i Move the cursor to the end of the line

    \row \i Ctrl+F \i Move the cursor one character right

    \row \i Ctrl+H \i Delete the character to the left of the cursor

    \row \i Ctrl+K \i Delete to end of line

    \row \i Ctrl+N \i Move the cursor one line down

    \row \i Ctrl+P \i Move the cursor one line up

    \row \i Ctrl+V \i Paste the clipboard text into line edit

                      (also Shift+Insert under Windows)

    \row \i Ctrl+X \i Cut the marked text, copy to clipboard

                      (also Shift+Delete under Windows)

    \row \i Ctrl+Z \i Undo the last operation

    \row \i Ctrl+Y \i Redo the last operation

    \row \i Left            \i Move the cursor one character left

    \row \i Ctrl+Left  \i Move the cursor one word left

    \row \i Right            \i Move the cursor one character right

    \row \i Ctrl+Right \i Move the cursor one word right

    \row \i Up            \i Move the cursor one line up

    \row \i Ctrl+Qt::Up    \i Move the cursor one word up

    \row \i DownArrow            \i Move the cursor one line down

    \row \i Ctrl+Down \i Move the cursor one word down

    \row \i PageUp            \i Move the cursor one page up

    \row \i PageDown            \i Move the cursor one page down