LyX 1.6.0 release candidate 4 (rc4)

[lyx.git] / src / BufferView.cpp

/**
 * \file BufferView.cpp
 * This file is part of LyX, the document processor.
 * Licence details can be found in the file COPYING.
 *
 * \author Alfredo Braunstein
 * \author Lars Gullik Bjønnes
 * \author John Levon
 * \author André Pönitz
 * \author Jürgen Vigna
 *
 * Full author contact details are available in file CREDITS.
 */

#include <config.h>

#include "BufferView.h"

#include "BranchList.h"
#include "Buffer.h"
#include "buffer_funcs.h"
#include "BufferList.h"
#include "BufferParams.h"
#include "CoordCache.h"
#include "Cursor.h"
#include "CutAndPaste.h"
#include "DispatchResult.h"
#include "ErrorList.h"
#include "factory.h"
#include "FloatList.h"
#include "FuncRequest.h"
#include "FuncStatus.h"
#include "Intl.h"
#include "InsetIterator.h"
#include "Language.h"
#include "LaTeXFeatures.h"
#include "LyX.h"
#include "lyxfind.h"
#include "LyXFunc.h"
#include "Layout.h"
#include "LyXRC.h"
#include "MetricsInfo.h"
#include "Paragraph.h"
#include "paragraph_funcs.h"
#include "ParagraphParameters.h"
#include "ParIterator.h"
#include "Session.h"
#include "Text.h"
#include "TextClass.h"
#include "TextMetrics.h"
#include "TexRow.h"
#include "TocBackend.h"
#include "VSpace.h"
#include "WordLangTuple.h"

#include "insets/InsetBibtex.h"
#include "insets/InsetCommand.h" // ChangeRefs
#include "insets/InsetExternal.h"
#include "insets/InsetGraphics.h"
#include "insets/InsetRef.h"
#include "insets/InsetText.h"
#include "insets/InsetNote.h"

#include "frontends/alert.h"
#include "frontends/Application.h"
#include "frontends/Delegates.h"
#include "frontends/FontMetrics.h"
#include "frontends/Painter.h"
#include "frontends/Selection.h"

#include "graphics/Previews.h"

#include "support/convert.h"
#include "support/debug.h"
#include "support/ExceptionMessage.h"
#include "support/filetools.h"
#include "support/gettext.h"
#include "support/lstrings.h"
#include "support/Package.h"
#include "support/types.h"

#include <cerrno>
#include <fstream>
#include <functional>
#include <iterator>
#include <vector>

using namespace std;
using namespace lyx::support;

namespace lyx {

namespace Alert = frontend::Alert;

namespace {

/// Return an inset of this class if it exists at the current cursor position
template <class T>
T * getInsetByCode(Cursor const & cur, InsetCode code)
{
        DocIterator it = cur;
        Inset * inset = it.nextInset();
        if (inset && inset->lyxCode() == code)
                return static_cast<T*>(inset);
        return 0;
}


bool findInset(DocIterator & dit, vector<InsetCode> const & codes,
        bool same_content);

bool findNextInset(DocIterator & dit, vector<InsetCode> const & codes,
        docstring const & contents)
{
        DocIterator tmpdit = dit;

        while (tmpdit) {
                Inset const * inset = tmpdit.nextInset();
                if (inset
                    && std::find(codes.begin(), codes.end(), inset->lyxCode()) != codes.end()
                    && (contents.empty() ||
                    static_cast<InsetCommand const *>(inset)->getFirstNonOptParam() == contents)) {
                        dit = tmpdit;
                        return true;
                }
                tmpdit.forwardInset();
        }

        return false;
}


/// Looks for next inset with one of the given codes.
bool findInset(DocIterator & dit, vector<InsetCode> const & codes,
        bool same_content)
{
        docstring contents;
        DocIterator tmpdit = dit;
        tmpdit.forwardInset();
        if (!tmpdit)
                return false;

        if (same_content) {
                Inset const * inset = tmpdit.nextInset();
                if (inset
                    && std::find(codes.begin(), codes.end(), inset->lyxCode()) != codes.end()) {
                        contents = static_cast<InsetCommand const *>(inset)->getFirstNonOptParam();
                }
        }

        if (!findNextInset(tmpdit, codes, contents)) {
                if (dit.depth() != 1 || dit.pit() != 0 || dit.pos() != 0) {
                        tmpdit  = doc_iterator_begin(tmpdit.bottom().inset());
                        if (!findNextInset(tmpdit, codes, contents))
                                return false;
                } else
                        return false;
        }

        dit = tmpdit;
        return true;
}


/// Looks for next inset with the given code
void findInset(DocIterator & dit, InsetCode code, bool same_content)
{
        findInset(dit, vector<InsetCode>(1, code), same_content);
}


/// Moves cursor to the next inset with one of the given codes.
void gotoInset(BufferView * bv, vector<InsetCode> const & codes,
               bool same_content)
{
        Cursor tmpcur = bv->cursor();
        if (!findInset(tmpcur, codes, same_content)) {
                bv->cursor().message(_("No more insets"));
                return;
        }

        tmpcur.clearSelection();
        bv->setCursor(tmpcur);
        bv->showCursor();
}


/// Moves cursor to the next inset with given code.
void gotoInset(BufferView * bv, InsetCode code, bool same_content)
{
        gotoInset(bv, vector<InsetCode>(1, code), same_content);
}


/// A map from a Text to the associated text metrics
typedef map<Text const *, TextMetrics> TextMetricsCache;

enum ScreenUpdateStrategy {
        NoScreenUpdate,
        SingleParUpdate,
        FullScreenUpdate,
        DecorationUpdate
};

} // anon namespace


/////////////////////////////////////////////////////////////////////
//
// BufferView
//
/////////////////////////////////////////////////////////////////////

struct BufferView::Private
{
        Private(BufferView & bv): wh_(0), cursor_(bv),
                anchor_pit_(0), anchor_ypos_(0),
                inlineCompletionUniqueChars_(0),
                last_inset_(0), gui_(0)
        {}

        ///
        ScrollbarParameters scrollbarParameters_;
        ///
        ScreenUpdateStrategy update_strategy_;
        ///
        CoordCache coord_cache_;

        /// Estimated average par height for scrollbar.
        int wh_;
        /// this is used to handle XSelection events in the right manner.
        struct {
                CursorSlice cursor;
                CursorSlice anchor;
                bool set;
        } xsel_cache_;
        ///
        Cursor cursor_;
        ///
        pit_type anchor_pit_;
        ///
        int anchor_ypos_;
        ///
        vector<int> par_height_;

        ///
        DocIterator inlineCompletionPos_;
        ///
        docstring inlineCompletion_;
        ///
        size_t inlineCompletionUniqueChars_;

        /// keyboard mapping object.
        Intl intl_;

        /// last visited inset.
        /** kept to send setMouseHover(false).
          * Not owned, so don't delete.
          */
        Inset * last_inset_;

        mutable TextMetricsCache text_metrics_;

        /// Whom to notify.
        /** Not owned, so don't delete.
          */
        frontend::GuiBufferViewDelegate * gui_;

        /// Cache for Find Next
        FuncRequest search_request_cache_;
};


BufferView::BufferView(Buffer & buf)
        : width_(0), height_(0), full_screen_(false), buffer_(buf), d(new Private(*this))
{
        d->xsel_cache_.set = false;
        d->intl_.initKeyMapper(lyxrc.use_kbmap);

        d->cursor_.push(buffer_.inset());
        d->cursor_.resetAnchor();
        d->cursor_.setCurrentFont();

        if (graphics::Previews::status() != LyXRC::PREVIEW_OFF)
                thePreviews().generateBufferPreviews(buffer_);
}


BufferView::~BufferView()
{
        // current buffer is going to be switched-off, save cursor pos
        // Ideally, the whole cursor stack should be saved, but session
        // currently can only handle bottom (whole document) level pit and pos.
        // That is to say, if a cursor is in a nested inset, it will be
        // restore to the left of the top level inset.
        LastFilePosSection::FilePos fp;
        fp.pit = d->cursor_.bottom().pit();
        fp.pos = d->cursor_.bottom().pos();
        theSession().lastFilePos().save(buffer_.fileName(), fp);

        delete d;
}


int BufferView::rightMargin() const
{
        // The additional test for the case the outliner is opened.
        if (!full_screen_ ||
                !lyxrc.full_screen_limit ||
                width_ < lyxrc.full_screen_width + 20)
                        return 10;

        return (width_ - lyxrc.full_screen_width) / 2;
}


int BufferView::leftMargin() const
{
        return rightMargin();
}


bool BufferView::isTopScreen() const
{
        return d->scrollbarParameters_.position == d->scrollbarParameters_.min;
}


bool BufferView::isBottomScreen() const
{
        return d->scrollbarParameters_.position == d->scrollbarParameters_.max;
}


Intl & BufferView::getIntl()
{
        return d->intl_;
}


Intl const & BufferView::getIntl() const
{
        return d->intl_;
}


CoordCache & BufferView::coordCache()
{
        return d->coord_cache_;
}


CoordCache const & BufferView::coordCache() const
{
        return d->coord_cache_;
}


Buffer & BufferView::buffer()
{
        return buffer_;
}


Buffer const & BufferView::buffer() const
{
        return buffer_;
}


bool BufferView::fitCursor()
{
        if (cursorStatus(d->cursor_) == CUR_INSIDE) {
                frontend::FontMetrics const & fm =
                        theFontMetrics(d->cursor_.getFont().fontInfo());
                int const asc = fm.maxAscent();
                int const des = fm.maxDescent();
                Point const p = getPos(d->cursor_, d->cursor_.boundary());
                if (p.y_ - asc >= 0 && p.y_ + des < height_)
                        return false;
        }
        return true;
}


void BufferView::processUpdateFlags(Update::flags flags)
{
        // last_inset_ points to the last visited inset. This pointer may become
        // invalid because of keyboard editing. Since all such operations
        // causes screen update(), I reset last_inset_ to avoid such a problem.
        d->last_inset_ = 0;
        // This is close to a hot-path.
        LYXERR(Debug::DEBUG, "BufferView::processUpdateFlags()"
                << "[fitcursor = " << (flags & Update::FitCursor)
                << ", forceupdate = " << (flags & Update::Force)
                << ", singlepar = " << (flags & Update::SinglePar)
                << "]  buffer: " << &buffer_);

        buffer_.updateMacros();

        // Now do the first drawing step if needed. This consists on updating
        // the CoordCache in updateMetrics().
        // The second drawing step is done in WorkArea::redraw() if needed.

        // Case when no explicit update is requested.
        if (!flags) {
                // no need to redraw anything.
                d->update_strategy_ = NoScreenUpdate;
                return;
        }

        if (flags == Update::Decoration) {
                d->update_strategy_ = DecorationUpdate;
                buffer_.changed();
                return;
        }

        if (flags == Update::FitCursor
                || flags == (Update::Decoration | Update::FitCursor)) {
                // tell the frontend to update the screen if needed.
                if (fitCursor()) {
                        showCursor();
                        return;
                }
                if (flags & Update::Decoration) {
                        d->update_strategy_ = DecorationUpdate;
                        buffer_.changed();
                        return;
                }
                // no screen update is needed.
                d->update_strategy_ = NoScreenUpdate;
                return;
        }

        bool const full_metrics = flags & Update::Force || !singleParUpdate();

        if (full_metrics)
                // We have to update the full screen metrics.
                updateMetrics();

        if (!(flags & Update::FitCursor)) {
                // Nothing to do anymore. Trigger a redraw and return
                buffer_.changed();
                return;
        }

        // updateMetrics() does not update paragraph position
        // This is done at draw() time. So we need a redraw!
        buffer_.changed();

        if (fitCursor()) {
                // The cursor is off screen so ensure it is visible.
                // refresh it:
                showCursor();
        }
}


void BufferView::updateScrollbar()
{
        if (height_ == 0 && width_ == 0)
                return;

        // We prefer fixed size line scrolling.
        d->scrollbarParameters_.single_step = defaultRowHeight();
        // We prefer full screen page scrolling.
        d->scrollbarParameters_.page_step = height_;

        Text & t = buffer_.text();
        TextMetrics & tm = d->text_metrics_[&t];                

        LYXERR(Debug::GUI, " Updating scrollbar: height: "
                << t.paragraphs().size()
                << " curr par: " << d->cursor_.bottom().pit()
                << " default height " << defaultRowHeight());

        size_t const parsize = t.paragraphs().size();
        if (d->par_height_.size() != parsize) {
                d->par_height_.clear();
                // FIXME: We assume a default paragraph height of 2 rows. This
                // should probably be pondered with the screen width.
                d->par_height_.resize(parsize, defaultRowHeight() * 2);
        }

        // Look at paragraph heights on-screen
        pair<pit_type, ParagraphMetrics const *> first = tm.first();
        pair<pit_type, ParagraphMetrics const *> last = tm.last();
        for (pit_type pit = first.first; pit <= last.first; ++pit) {
                d->par_height_[pit] = tm.parMetrics(pit).height();
                LYXERR(Debug::SCROLLING, "storing height for pit " << pit << " : "
                        << d->par_height_[pit]);
        }

        int top_pos = first.second->position() - first.second->ascent();
        int bottom_pos = last.second->position() + last.second->descent();
        bool first_visible = first.first == 0 && top_pos >= 0;
        bool last_visible = last.first + 1 == int(parsize) && bottom_pos <= height_;
        if (first_visible && last_visible) {
                d->scrollbarParameters_.min = 0;
                d->scrollbarParameters_.max = 0;
                return;
        }

        d->scrollbarParameters_.min = top_pos;
        for (size_t i = 0; i != size_t(first.first); ++i)
                d->scrollbarParameters_.min -= d->par_height_[i];
        d->scrollbarParameters_.max = bottom_pos;
        for (size_t i = last.first + 1; i != parsize; ++i)
                d->scrollbarParameters_.max += d->par_height_[i];

        d->scrollbarParameters_.position = 0;
        // The reference is the top position so we remove one page.
        d->scrollbarParameters_.max -= d->scrollbarParameters_.page_step;
}


ScrollbarParameters const & BufferView::scrollbarParameters() const
{
        return d->scrollbarParameters_;
}


docstring BufferView::toolTip(int x, int y) const
{
        // Get inset under mouse, if there is one.
        Inset const * covering_inset = getCoveringInset(buffer_.text(), x, y);
        if (!covering_inset)
                // No inset, no tooltip...
                return docstring();
        return covering_inset->toolTip(*this, x, y);
}


docstring BufferView::contextMenu(int x, int y) const
{
        //If there is a selection, return the containing inset menu
        if (d->cursor_.selection())
                return d->cursor_.inset().contextMenu(*this, x, y);

        // Get inset under mouse, if there is one.
        Inset const * covering_inset = getCoveringInset(buffer_.text(), x, y);
        if (covering_inset)
                return covering_inset->contextMenu(*this, x, y);

        return buffer_.inset().contextMenu(*this, x, y);
}


void BufferView::scrollDocView(int value)
{
        int const offset = value - d->scrollbarParameters_.position;
        // If the offset is less than 2 screen height, prefer to scroll instead.
        if (abs(offset) <= 2 * height_) {
                scroll(offset);
                updateMetrics();
                buffer_.changed();
                return;
        }

        // cut off at the top
        if (value <= d->scrollbarParameters_.min) {
                DocIterator dit = doc_iterator_begin(buffer_.inset());
                showCursor(dit);
                LYXERR(Debug::SCROLLING, "scroll to top");
                return;
        }

        // cut off at the bottom
        if (value >= d->scrollbarParameters_.max) {
                DocIterator dit = doc_iterator_end(buffer_.inset());
                dit.backwardPos();
                showCursor(dit);
                LYXERR(Debug::SCROLLING, "scroll to bottom");
                return;
        }

        // find paragraph at target position
        int par_pos = d->scrollbarParameters_.min;
        pit_type i = 0;
        for (; i != int(d->par_height_.size()); ++i) {
                par_pos += d->par_height_[i];
                if (par_pos >= value)
                        break;
        }

        if (par_pos < value) {
                // It seems we didn't find the correct pit so stay on the safe side and
                // scroll to bottom.
                LYXERR0("scrolling position not found!");
                scrollDocView(d->scrollbarParameters_.max);
                return;
        }

        DocIterator dit = doc_iterator_begin(buffer_.inset());
        dit.pit() = i;
        LYXERR(Debug::SCROLLING, "value = " << value << " -> scroll to pit " << i);
        showCursor(dit);
}


// FIXME: this method is not working well.
void BufferView::setCursorFromScrollbar()
{
        TextMetrics & tm = d->text_metrics_[&buffer_.text()];

        int const height = 2 * defaultRowHeight();
        int const first = height;
        int const last = height_ - height;
        int newy = 0;
        Cursor const & oldcur = d->cursor_;

        switch (cursorStatus(oldcur)) {
        case CUR_ABOVE:
                newy = first;
                break;
        case CUR_BELOW:
                newy = last;
                break;
        case CUR_INSIDE:
                int const y = getPos(oldcur, oldcur.boundary()).y_;
                newy = min(last, max(y, first));
                if (y == newy) 
                        return;
        }
        // We reset the cursor because cursorStatus() does not
        // work when the cursor is within mathed.
        Cursor cur(*this);
        cur.reset(buffer_.inset());
        tm.setCursorFromCoordinates(cur, 0, newy);
        mouseSetCursor(cur);
}


Change const BufferView::getCurrentChange() const
{
        if (!d->cursor_.selection())
                return Change(Change::UNCHANGED);

        DocIterator dit = d->cursor_.selectionBegin();
        return dit.paragraph().lookupChange(dit.pos());
}


// this could be used elsewhere as well?
// FIXME: This does not work within mathed!
CursorStatus BufferView::cursorStatus(DocIterator const & dit) const
{
        Point const p = getPos(dit, dit.boundary());
        if (p.y_ < 0)
                return CUR_ABOVE;
        if (p.y_ > workHeight())
                return CUR_BELOW;
        return CUR_INSIDE;
}


void BufferView::saveBookmark(unsigned int idx)
{
        // tenatively save bookmark, id and pos will be used to
        // acturately locate a bookmark in a 'live' lyx session.
        // pit and pos will be updated with bottom level pit/pos
        // when lyx exits.
        theSession().bookmarks().save(
                buffer_.fileName(),
                d->cursor_.bottom().pit(),
                d->cursor_.bottom().pos(),
                d->cursor_.paragraph().id(),
                d->cursor_.pos(),
                idx
        );
        if (idx)
                // emit message signal.
                message(_("Save bookmark"));
}


bool BufferView::moveToPosition(pit_type bottom_pit, pos_type bottom_pos,
        int top_id, pos_type top_pos)
{
        bool success = false;
        DocIterator dit;

        d->cursor_.clearSelection();

        // if a valid par_id is given, try it first
        // This is the case for a 'live' bookmark when unique paragraph ID
        // is used to track bookmarks.
        if (top_id > 0) {
                dit = buffer_.getParFromID(top_id);
                if (!dit.atEnd()) {
                        dit.pos() = min(dit.paragraph().size(), top_pos);
                        // Some slices of the iterator may not be
                        // reachable (e.g. closed collapsable inset)
                        // so the dociterator may need to be
                        // shortened. Otherwise, setCursor may crash
                        // lyx when the cursor can not be set to these
                        // insets.
                        size_t const n = dit.depth();
                        for (size_t i = 0; i < n; ++i)
                                if (dit[i].inset().editable() != Inset::HIGHLY_EDITABLE) {
                                        dit.resize(i);
                                        break;
                                }
                        success = true;
                }
        }

        // if top_id == 0, or searching through top_id failed
        // This is the case for a 'restored' bookmark when only bottom
        // (document level) pit was saved. Because of this, bookmark
        // restoration is inaccurate. If a bookmark was within an inset,
        // it will be restored to the left of the outmost inset that contains
        // the bookmark.
        if (bottom_pit < int(buffer_.paragraphs().size())) {
                dit = doc_iterator_begin(buffer_.inset());
                                
                dit.pit() = bottom_pit;
                dit.pos() = min(bottom_pos, dit.paragraph().size());
                success = true;
        }

        if (success) {
                // Note: only bottom (document) level pit is set.
                setCursor(dit);
                // set the current font.
                d->cursor_.setCurrentFont();
                // To center the screen on this new position we need the
                // paragraph position which is computed at draw() time.
                // So we need a redraw!
                buffer_.changed();
                if (fitCursor())
                        showCursor();
        }

        return success;
}


void BufferView::translateAndInsert(char_type c, Text * t, Cursor & cur)
{
        if (lyxrc.rtl_support) {
                if (d->cursor_.real_current_font.isRightToLeft()) {
                        if (d->intl_.keymap == Intl::PRIMARY)
                                d->intl_.keyMapSec();
                } else {
                        if (d->intl_.keymap == Intl::SECONDARY)
                                d->intl_.keyMapPrim();
                }
        }

        d->intl_.getTransManager().translateAndInsert(c, t, cur);
}


int BufferView::workWidth() const
{
        return width_;
}


void BufferView::showCursor()
{
        showCursor(d->cursor_);
}


void BufferView::showCursor(DocIterator const & dit)
{
        // We are not properly started yet, delay until resizing is
        // done.
        if (height_ == 0)
                return;

        LYXERR(Debug::SCROLLING, "recentering!");

        CursorSlice const & bot = dit.bottom();
        TextMetrics & tm = d->text_metrics_[bot.text()];

        pos_type const max_pit = pos_type(bot.text()->paragraphs().size() - 1);
        int bot_pit = bot.pit();
        if (bot_pit > max_pit) {
                // FIXME: Why does this happen?
                LYXERR0("bottom pit is greater that max pit: "
                        << bot_pit << " > " << max_pit);
                bot_pit = max_pit;
        }

        if (bot_pit == tm.first().first - 1)
                tm.newParMetricsUp();
        else if (bot_pit == tm.last().first + 1)
                tm.newParMetricsDown();

        if (tm.contains(bot_pit)) {
                ParagraphMetrics const & pm = tm.parMetrics(bot_pit);
                LASSERT(!pm.rows().empty(), /**/);
                // FIXME: smooth scrolling doesn't work in mathed.
                CursorSlice const & cs = dit.innerTextSlice();
                int offset = coordOffset(dit, dit.boundary()).y_;
                int ypos = pm.position() + offset;
                Dimension const & row_dim =
                        pm.getRow(cs.pos(), dit.boundary()).dimension();
                int scrolled = 0;
                if (ypos - row_dim.ascent() < 0)
                        scrolled = scrollUp(- ypos + row_dim.ascent());
                else if (ypos + row_dim.descent() > height_)
                        scrolled = scrollDown(ypos - height_ + row_dim.descent());
                // else, nothing to do, the cursor is already visible so we just return.
                if (scrolled != 0) {
                        updateMetrics();
                        buffer_.changed();
                }
                return;
        }

        // fix inline completion position
        if (d->inlineCompletionPos_.fixIfBroken())
                d->inlineCompletionPos_ = DocIterator();

        tm.redoParagraph(bot_pit);
        ParagraphMetrics const & pm = tm.parMetrics(bot_pit);
        int offset = coordOffset(dit, dit.boundary()).y_;

        d->anchor_pit_ = bot_pit;
        CursorSlice const & cs = dit.innerTextSlice();
        Dimension const & row_dim =
                pm.getRow(cs.pos(), dit.boundary()).dimension();

        if (d->anchor_pit_ == 0)
                d->anchor_ypos_ = offset + pm.ascent();
        else if (d->anchor_pit_ == max_pit)
                d->anchor_ypos_ = height_ - offset - row_dim.descent();
        else
                d->anchor_ypos_ = defaultRowHeight() * 2 - offset - row_dim.descent();

        updateMetrics();
        buffer_.changed();
}


FuncStatus BufferView::getStatus(FuncRequest const & cmd)
{
        FuncStatus flag;

        Cursor & cur = d->cursor_;

        switch (cmd.action) {

        case LFUN_UNDO:
                flag.setEnabled(buffer_.undo().hasUndoStack());
                break;
        case LFUN_REDO:
                flag.setEnabled(buffer_.undo().hasRedoStack());
                break;
        case LFUN_FILE_INSERT:
        case LFUN_FILE_INSERT_PLAINTEXT_PARA:
        case LFUN_FILE_INSERT_PLAINTEXT:
        case LFUN_BOOKMARK_SAVE:
                // FIXME: Actually, these LFUNS should be moved to Text
                flag.setEnabled(cur.inTexted());
                break;
        case LFUN_FONT_STATE:
        case LFUN_LABEL_INSERT:
        case LFUN_INFO_INSERT:
        case LFUN_INSET_EDIT:
        case LFUN_PARAGRAPH_GOTO:
        case LFUN_NOTE_NEXT:
        case LFUN_REFERENCE_NEXT:
        case LFUN_WORD_FIND:
        case LFUN_WORD_REPLACE:
        case LFUN_MARK_OFF:
        case LFUN_MARK_ON:
        case LFUN_MARK_TOGGLE:
        case LFUN_SCREEN_RECENTER:
        case LFUN_BIBTEX_DATABASE_ADD:
        case LFUN_BIBTEX_DATABASE_DEL:
        case LFUN_NOTES_MUTATE:
        case LFUN_ALL_INSETS_TOGGLE:
        case LFUN_STATISTICS:
                flag.setEnabled(true);
                break;

        case LFUN_NEXT_INSET_TOGGLE: 
        case LFUN_NEXT_INSET_MODIFY: {
                // this is the real function we want to invoke
                FuncRequest tmpcmd = cmd;
                tmpcmd.action = (cmd.action == LFUN_NEXT_INSET_TOGGLE) 
                        ? LFUN_INSET_TOGGLE : LFUN_INSET_MODIFY;
                // if there is an inset at cursor, see whether it
                // handles the lfun, other start from scratch
                Inset * inset = cur.nextInset();
                if (!inset || !inset->getStatus(cur, tmpcmd, flag))
                        flag = lyx::getStatus(tmpcmd);
                break;
        }

        case LFUN_LABEL_GOTO: {
                flag.setEnabled(!cmd.argument().empty()
                    || getInsetByCode<InsetRef>(cur, REF_CODE));
                break;
        }

        case LFUN_CHANGES_TRACK:
                flag.setEnabled(true);
                flag.setOnOff(buffer_.params().trackChanges);
                break;

        case LFUN_CHANGES_OUTPUT:
                flag.setEnabled(true);
                flag.setOnOff(buffer_.params().outputChanges);
                break;

        case LFUN_CHANGES_MERGE:
        case LFUN_CHANGE_NEXT:
        case LFUN_ALL_CHANGES_ACCEPT:
        case LFUN_ALL_CHANGES_REJECT:
                // TODO: context-sensitive enabling of LFUNs
                // In principle, these command should only be enabled if there
                // is a change in the document. However, without proper
                // optimizations, this will inevitably result in poor performance.
                flag.setEnabled(true);
                break;

        case LFUN_BUFFER_TOGGLE_COMPRESSION: {
                flag.setOnOff(buffer_.params().compressed);
                break;
        }
        
        case LFUN_SCREEN_UP:
        case LFUN_SCREEN_DOWN:
        case LFUN_SCROLL:
        case LFUN_SCREEN_UP_SELECT:
        case LFUN_SCREEN_DOWN_SELECT:
                flag.setEnabled(true);
                break;

        case LFUN_LAYOUT_TABULAR:
                flag.setEnabled(cur.innerInsetOfType(TABULAR_CODE));
                break;

        case LFUN_LAYOUT:
                flag.setEnabled(!cur.inset().forcePlainLayout(cur.idx()));
                break;

        case LFUN_LAYOUT_PARAGRAPH:
                flag.setEnabled(cur.inset().allowParagraphCustomization(cur.idx()));
                break;

        case LFUN_INSET_SETTINGS: {
                InsetCode code = cur.inset().lyxCode();
                if (cmd.getArg(0) == insetName(code)) {
                        flag.setEnabled(true);
                        break;
                }
                bool enable = false;
                InsetCode next_code = cur.nextInset()
                        ? cur.nextInset()->lyxCode() : NO_CODE;
                //FIXME: remove these special cases:
                switch (next_code) {
                        case TABULAR_CODE:
                        case ERT_CODE:
                        case FLOAT_CODE:
                        case WRAP_CODE:
                        case NOTE_CODE:
                        case BRANCH_CODE:
                        case BOX_CODE:
                        case LISTINGS_CODE:
                                enable = (cmd.argument().empty() ||
                                          cmd.getArg(0) == insetName(next_code));
                                break;
                        default:
                                break;
                }
                flag.setEnabled(enable);
                break;
        }

        case LFUN_DIALOG_SHOW_NEW_INSET:
                flag.setEnabled(cur.inset().lyxCode() != ERT_CODE &&
                        cur.inset().lyxCode() != LISTINGS_CODE);
                if (cur.inset().lyxCode() == CAPTION_CODE) {
                        FuncStatus flag;
                        if (cur.inset().getStatus(cur, cmd, flag))
                                return flag;
                }
                break;

        case LFUN_BRANCH_ACTIVATE: 
        case LFUN_BRANCH_DEACTIVATE: {
                bool enable = false;
                docstring const branchName = cmd.argument();
                if (!branchName.empty())
                        enable = buffer_.params().branchlist().find(branchName);
                flag.setEnabled(enable);
                break;
        }

        default:
                flag.setEnabled(false);
        }

        return flag;
}


bool BufferView::dispatch(FuncRequest const & cmd)
{
        //lyxerr << [ cmd = " << cmd << "]" << endl;

        // Make sure that the cached BufferView is correct.
        LYXERR(Debug::ACTION, " action[" << cmd.action << ']'
                << " arg[" << to_utf8(cmd.argument()) << ']'
                << " x[" << cmd.x << ']'
                << " y[" << cmd.y << ']'
                << " button[" << cmd.button() << ']');

        Cursor & cur = d->cursor_;

        switch (cmd.action) {

        case LFUN_UNDO:
                cur.message(_("Undo"));
                cur.clearSelection();
                if (!cur.textUndo())
                        cur.message(_("No further undo information"));
                else
                        processUpdateFlags(Update::Force | Update::FitCursor);
                break;

        case LFUN_REDO:
                cur.message(_("Redo"));
                cur.clearSelection();
                if (!cur.textRedo())
                        cur.message(_("No further redo information"));
                else
                        processUpdateFlags(Update::Force | Update::FitCursor);
                break;

        case LFUN_FONT_STATE:
                cur.message(cur.currentState());
                break;

        case LFUN_BOOKMARK_SAVE:
                saveBookmark(convert<unsigned int>(to_utf8(cmd.argument())));
                break;

        case LFUN_LABEL_GOTO: {
                docstring label = cmd.argument();
                if (label.empty()) {
                        InsetRef * inset =
                                getInsetByCode<InsetRef>(d->cursor_,
                                                         REF_CODE);
                        if (inset) {
                                label = inset->getParam("reference");
                                // persistent=false: use temp_bookmark
                                saveBookmark(0);
                        }
                }

                if (!label.empty())
                        gotoLabel(label);
                break;
        }
        
        case LFUN_INSET_EDIT: {
                FuncRequest fr(cmd);
                // if there is an inset at cursor, see whether it
                // can be modified.
                Inset * inset = cur.nextInset();
                if (inset)
                        inset->dispatch(cur, fr);
                // if it did not work, try the underlying inset.
                if (!inset || !cur.result().dispatched())
                        cur.dispatch(cmd);

                // FIXME I'm adding the last break to solve a crash,
                // but that is obviously not right.
                if (!cur.result().dispatched())
                        // It did not work too; no action needed.
                        break;
                break;
        }

        case LFUN_PARAGRAPH_GOTO: {
                int const id = convert<int>(cmd.getArg(0));
                int const pos = convert<int>(cmd.getArg(1));
                int i = 0;
                for (Buffer * b = &buffer_; i == 0 || b != &buffer_;
                        b = theBufferList().next(b)) {

                        DocIterator dit = b->getParFromID(id);
                        if (dit.atEnd()) {
                                LYXERR(Debug::INFO, "No matching paragraph found! [" << id << "].");
                                ++i;
                                continue;
                        }
                        LYXERR(Debug::INFO, "Paragraph " << dit.paragraph().id()
                                << " found in buffer `"
                                << b->absFileName() << "'.");

                        if (b == &buffer_) {
                                // Set the cursor
                                dit.pos() = pos;
                                setCursor(dit);
                                processUpdateFlags(Update::Force | Update::FitCursor);
                        } else {
                                // Switch to other buffer view and resend cmd
                                theLyXFunc().dispatch(FuncRequest(
                                        LFUN_BUFFER_SWITCH, b->absFileName()));
                                theLyXFunc().dispatch(cmd);
                        }
                        break;
                }
                break;
        }

        case LFUN_NOTE_NEXT:
                gotoInset(this, NOTE_CODE, false);
                break;

        case LFUN_REFERENCE_NEXT: {
                vector<InsetCode> tmp;
                tmp.push_back(LABEL_CODE);
                tmp.push_back(REF_CODE);
                gotoInset(this, tmp, true);
                break;
        }

        case LFUN_CHANGES_TRACK:
                buffer_.params().trackChanges = !buffer_.params().trackChanges;
                break;

        case LFUN_CHANGES_OUTPUT:
                buffer_.params().outputChanges = !buffer_.params().outputChanges;
                if (buffer_.params().outputChanges) {
                        bool dvipost    = LaTeXFeatures::isAvailable("dvipost");
                        bool xcolorsoul = LaTeXFeatures::isAvailable("soul") &&
                                          LaTeXFeatures::isAvailable("xcolor");

                        if (!dvipost && !xcolorsoul) {
                                Alert::warning(_("Changes not shown in LaTeX output"),
                                               _("Changes will not be highlighted in LaTeX output, "
                                                 "because neither dvipost nor xcolor/soul are installed.\n"
                                                 "Please install these packages or redefine "
                                                 "\\lyxadded and \\lyxdeleted in the LaTeX preamble."));
                        } else if (!xcolorsoul) {
                                Alert::warning(_("Changes not shown in LaTeX output"),
                                               _("Changes will not be highlighted in LaTeX output "
                                                 "when using pdflatex, because xcolor and soul are not installed.\n"
                                                 "Please install both packages or redefine "
                                                 "\\lyxadded and \\lyxdeleted in the LaTeX preamble."));
                        }
                }
                break;

        case LFUN_CHANGE_NEXT:
                findNextChange(this);
                break;

        case LFUN_CHANGES_MERGE:
                if (findNextChange(this))
                        showDialog("changes");
                break;

        case LFUN_ALL_CHANGES_ACCEPT:
                // select complete document
                d->cursor_.reset(buffer_.inset());
                d->cursor_.selHandle(true);
                buffer_.text().cursorBottom(d->cursor_);
                // accept everything in a single step to support atomic undo
                buffer_.text().acceptOrRejectChanges(d->cursor_, Text::ACCEPT);
                // FIXME: Move this LFUN to Buffer so that we don't have to do this:
                processUpdateFlags(Update::Force | Update::FitCursor);
                break;

        case LFUN_ALL_CHANGES_REJECT:
                // select complete document
                d->cursor_.reset(buffer_.inset());
                d->cursor_.selHandle(true);
                buffer_.text().cursorBottom(d->cursor_);
                // reject everything in a single step to support atomic undo
                // Note: reject does not work recursively; the user may have to repeat the operation
                buffer_.text().acceptOrRejectChanges(d->cursor_, Text::REJECT);
                // FIXME: Move this LFUN to Buffer so that we don't have to do this:
                processUpdateFlags(Update::Force | Update::FitCursor);
                break;

        case LFUN_WORD_FIND: {
                FuncRequest req = cmd;
                if (cmd.argument().empty() && !d->search_request_cache_.argument().empty())
                        req = d->search_request_cache_;
                if (req.argument().empty()) {
                        theLyXFunc().dispatch(FuncRequest(LFUN_DIALOG_SHOW, "findreplace"));
                        break;
                }
                if (find(this, req))
                        showCursor();
                else
                        message(_("String not found!"));
                d->search_request_cache_ = req;
                break;
        }

        case LFUN_WORD_REPLACE: {
                bool has_deleted = false;
                if (cur.selection()) {
                        DocIterator beg = cur.selectionBegin();
                        DocIterator end = cur.selectionEnd();
                        if (beg.pit() == end.pit()) {
                                for (pos_type p = beg.pos() ; p < end.pos() ; ++p) {
                                        if (cur.paragraph().isDeleted(p))
                                                has_deleted = true;
                                }
                        }
                }
                replace(this, cmd, has_deleted);
                break;
        }

        case LFUN_MARK_OFF:
                cur.clearSelection();
                cur.resetAnchor();
                cur.message(from_utf8(N_("Mark off")));
                break;

        case LFUN_MARK_ON:
                cur.clearSelection();
                cur.setMark(true);
                cur.resetAnchor();
                cur.message(from_utf8(N_("Mark on")));
                break;

        case LFUN_MARK_TOGGLE:
                cur.clearSelection();
                if (cur.mark()) {
                        cur.setMark(false);
                        cur.message(from_utf8(N_("Mark removed")));
                } else {
                        cur.setMark(true);
                        cur.message(from_utf8(N_("Mark set")));
                }
                cur.resetAnchor();
                break;

        case LFUN_SCREEN_RECENTER:
                showCursor();
                break;

        case LFUN_BIBTEX_DATABASE_ADD: {
                Cursor tmpcur = d->cursor_;
                findInset(tmpcur, BIBTEX_CODE, false);
                InsetBibtex * inset = getInsetByCode<InsetBibtex>(tmpcur,
                                                BIBTEX_CODE);
                if (inset) {
                        if (inset->addDatabase(cmd.argument()))
                                buffer_.updateBibfilesCache();
                }
                break;
        }

        case LFUN_BIBTEX_DATABASE_DEL: {
                Cursor tmpcur = d->cursor_;
                findInset(tmpcur, BIBTEX_CODE, false);
                InsetBibtex * inset = getInsetByCode<InsetBibtex>(tmpcur,
                                                BIBTEX_CODE);
                if (inset) {
                        if (inset->delDatabase(cmd.argument()))
                                buffer_.updateBibfilesCache();
                }
                break;
        }

        case LFUN_STATISTICS: {
                DocIterator from, to;
                if (cur.selection()) {
                        from = cur.selectionBegin();
                        to = cur.selectionEnd();
                } else {
                        from = doc_iterator_begin(buffer_.inset());
                        to = doc_iterator_end(buffer_.inset());
                }
                int const words = countWords(from, to);
                int const chars = countChars(from, to, false);
                int const chars_blanks = countChars(from, to, true);
                docstring message;
                if (cur.selection())
                        message = _("Statistics for the selection:");
                else
                        message = _("Statistics for the document:");
                message += "\n\n";
                if (words != 1)
                        message += bformat(_("%1$d words"), words);
                else
                        message += _("One word");
                message += "\n";
                if (chars_blanks != 1)
                        message += bformat(_("%1$d characters (including blanks)"),
                                          chars_blanks);
                else
                        message += _("One character (including blanks)");
                message += "\n";
                if (chars != 1)
                        message += bformat(_("%1$d characters (excluding blanks)"),
                                          chars);
                else
                        message += _("One character (excluding blanks)");

                Alert::information(_("Statistics"), message);
        }
                break;

        case LFUN_BUFFER_TOGGLE_COMPRESSION:
                // turn compression on/off
                buffer_.params().compressed = !buffer_.params().compressed;
                break;
        
        case LFUN_NEXT_INSET_TOGGLE: {
                // create the the real function we want to invoke
                FuncRequest tmpcmd = cmd;
                tmpcmd.action = LFUN_INSET_TOGGLE;
                // if there is an inset at cursor, see whether it
                // wants to toggle.
                Inset * inset = cur.nextInset();
                if (inset) {
                        if (inset->isActive()) {
                                Cursor tmpcur = cur;
                                tmpcur.pushBackward(*inset);
                                inset->dispatch(tmpcur, tmpcmd);
                                if (tmpcur.result().dispatched())
                                        cur.dispatched();
                        } else 
                                inset->dispatch(cur, tmpcmd);
                }
                // if it did not work, try the underlying inset.
                if (!inset || !cur.result().dispatched())
                        cur.dispatch(tmpcmd);

                if (!cur.result().dispatched())
                        // It did not work too; no action needed.
                        break;
                cur.clearSelection();
                processUpdateFlags(Update::SinglePar | Update::FitCursor);
                break;
        }

        case LFUN_NEXT_INSET_MODIFY: {
                // create the the real function we want to invoke
                FuncRequest tmpcmd = cmd;
                tmpcmd.action = LFUN_INSET_MODIFY;
                // if there is an inset at cursor, see whether it
                // can be modified.
                Inset * inset = cur.nextInset();
                if (inset)
                        inset->dispatch(cur, tmpcmd);
                // if it did not work, try the underlying inset.
                if (!inset || !cur.result().dispatched())
                        cur.dispatch(tmpcmd);

                if (!cur.result().dispatched())
                        // It did not work too; no action needed.
                        break;
                cur.clearSelection();
                processUpdateFlags(Update::Force | Update::FitCursor);
                break;
        }

        case LFUN_SCREEN_UP:
        case LFUN_SCREEN_DOWN: {
                Point p = getPos(cur, cur.boundary());
                if (p.y_ < 0 || p.y_ > height_) {
                        // The cursor is off-screen so recenter before proceeding.
                        showCursor();
                        p = getPos(cur, cur.boundary());
                }
                int const scrolled = scroll(cmd.action == LFUN_SCREEN_UP
                        ? - height_ : height_);
                if (cmd.action == LFUN_SCREEN_UP && scrolled > - height_)
                        p = Point(0, 0);
                if (cmd.action == LFUN_SCREEN_DOWN && scrolled < height_)
                        p = Point(width_, height_);
                cur.reset(buffer_.inset());
                updateMetrics();
                buffer_.changed();
                d->text_metrics_[&buffer_.text()].editXY(cur, p.x_, p.y_);
                //FIXME: what to do with cur.x_target()?
                cur.finishUndo();
                break;
        }

        case LFUN_SCROLL:
                lfunScroll(cmd);
                break;

        case LFUN_SCREEN_UP_SELECT: {
                cur.selHandle(true);
                if (isTopScreen()) {
                        lyx::dispatch(FuncRequest(LFUN_BUFFER_BEGIN_SELECT));
                        cur.finishUndo();
                        break;
                }
                int y = getPos(cur, cur.boundary()).y_;
                int const ymin = y - height_ + defaultRowHeight();
                while (y > ymin && cur.up())
                        y = getPos(cur, cur.boundary()).y_;

                cur.finishUndo();
                processUpdateFlags(Update::SinglePar | Update::FitCursor);
                break;
        }

        case LFUN_SCREEN_DOWN_SELECT: {
                cur.selHandle(true);
                if (isBottomScreen()) {
                        lyx::dispatch(FuncRequest(LFUN_BUFFER_END_SELECT));
                        cur.finishUndo();
                        break;
                }
                int y = getPos(cur, cur.boundary()).y_;
                int const ymax = y + height_ - defaultRowHeight();
                while (y < ymax && cur.down())
                        y = getPos(cur, cur.boundary()).y_;

                cur.finishUndo();
                processUpdateFlags(Update::SinglePar | Update::FitCursor);
                break;
        }

        case LFUN_BRANCH_ACTIVATE:
        case LFUN_BRANCH_DEACTIVATE:
                buffer_.dispatch(cmd);
                processUpdateFlags(Update::Force);
                break;

        // This could be rewriten using some command like forall <insetname> <command>
        // once the insets refactoring is done.
        case LFUN_NOTES_MUTATE: {
                if (cmd.argument().empty())
                        break;

                if (mutateNotes(cur, cmd.getArg(0), cmd.getArg(1))) {
                        processUpdateFlags(Update::Force);
                }
                break;
        }

        case LFUN_ALL_INSETS_TOGGLE: {
                string action;
                string const name = split(to_utf8(cmd.argument()), action, ' ');
                InsetCode const inset_code = insetCode(name);

                FuncRequest fr(LFUN_INSET_TOGGLE, action);

                Inset & inset = cur.buffer().inset();
                InsetIterator it  = inset_iterator_begin(inset);
                InsetIterator const end = inset_iterator_end(inset);
                for (; it != end; ++it) {
                        if (it->asInsetCollapsable()
                            && (inset_code == NO_CODE
                            || inset_code == it->lyxCode())) {
                                Cursor tmpcur = cur;
                                tmpcur.pushBackward(*it);
                                it->dispatch(tmpcur, fr);
                        }
                }
                processUpdateFlags(Update::Force | Update::FitCursor);
                break;
        }

        default:
                return false;
        }

        return true;
}


docstring const BufferView::requestSelection()
{
        Cursor & cur = d->cursor_;

        LYXERR(Debug::SELECTION, "requestSelection: cur.selection: " << cur.selection());
        if (!cur.selection()) {
                d->xsel_cache_.set = false;
                return docstring();
        }

        LYXERR(Debug::SELECTION, "requestSelection: xsel_cache.set: " << d->xsel_cache_.set);
        if (!d->xsel_cache_.set ||
            cur.top() != d->xsel_cache_.cursor ||
            cur.anchor_.top() != d->xsel_cache_.anchor)
        {
                d->xsel_cache_.cursor = cur.top();
                d->xsel_cache_.anchor = cur.anchor_.top();
                d->xsel_cache_.set = cur.selection();
                return cur.selectionAsString(false);
        }
        return docstring();
}


void BufferView::clearSelection()
{
        d->cursor_.clearSelection();
        // Clear the selection buffer. Otherwise a subsequent
        // middle-mouse-button paste would use the selection buffer,
        // not the more current external selection.
        cap::clearSelection();
        d->xsel_cache_.set = false;
        // The buffer did not really change, but this causes the
        // redraw we need because we cleared the selection above.
        buffer_.changed();
}


void BufferView::resize(int width, int height)
{
        // Update from work area
        width_ = width;
        height_ = height;

        // Clear the paragraph height cache.
        d->par_height_.clear();
        // Redo the metrics.
        updateMetrics();
}


Inset const * BufferView::getCoveringInset(Text const & text,
                int x, int y) const
{
        TextMetrics & tm = d->text_metrics_[&text];
        Inset * inset = tm.checkInsetHit(x, y);
        if (!inset)
                return 0;

        if (!inset->descendable())
                // No need to go further down if the inset is not
                // descendable.
                return inset;

        size_t cell_number = inset->nargs();
        // Check all the inner cell.
        for (size_t i = 0; i != cell_number; ++i) {
                Text const * inner_text = inset->getText(i);
                if (inner_text) {
                        // Try deeper.
                        Inset const * inset_deeper =
                                getCoveringInset(*inner_text, x, y);
                        if (inset_deeper)
                                return inset_deeper;
                }
        }

        return inset;
}


void BufferView::mouseEventDispatch(FuncRequest const & cmd0)
{
        //lyxerr << "[ cmd0 " << cmd0 << "]" << endl;

        // This is only called for mouse related events including
        // LFUN_FILE_OPEN generated by drag-and-drop.
        FuncRequest cmd = cmd0;

        Cursor old = cursor();
        Cursor cur(*this);
        cur.push(buffer_.inset());
        cur.setSelection(d->cursor_.selection());

        // Either the inset under the cursor or the
        // surrounding Text will handle this event.

        // make sure we stay within the screen...
        cmd.y = min(max(cmd.y, -1), height_);

        if (cmd.action == LFUN_MOUSE_MOTION && cmd.button() == mouse_button::none) {

                // Get inset under mouse, if there is one.
                Inset const * covering_inset =
                        getCoveringInset(buffer_.text(), cmd.x, cmd.y);
                if (covering_inset == d->last_inset_)
                        // Same inset, no need to do anything...
                        return;

                bool need_redraw = false;
                // const_cast because of setMouseHover().
                Inset * inset = const_cast<Inset *>(covering_inset);
                if (d->last_inset_)
                        // Remove the hint on the last hovered inset (if any).
                        need_redraw |= d->last_inset_->setMouseHover(false);
                if (inset)
                        // Highlighted the newly hovered inset (if any).
                        need_redraw |= inset->setMouseHover(true);
                d->last_inset_ = inset;
                if (!need_redraw)
                        return;

                LYXERR(Debug::PAINTING, "Mouse hover detected at: ("
                        << cmd.x << ", " << cmd.y << ")");

                d->update_strategy_ = DecorationUpdate;

                // This event (moving without mouse click) is not passed further.
                // This should be changed if it is further utilized.
                buffer_.changed();
                return;
        }

        // Build temporary cursor.
        Inset * inset = d->text_metrics_[&buffer_.text()].editXY(cur, cmd.x, cmd.y);

        // Put anchor at the same position.
        cur.resetAnchor();

        cur.beginUndoGroup();

        // Try to dispatch to an non-editable inset near this position
        // via the temp cursor. If the inset wishes to change the real
        // cursor it has to do so explicitly by using
        //  cur.bv().cursor() = cur;  (or similar)
        if (inset)
                inset->dispatch(cur, cmd);

        // Now dispatch to the temporary cursor. If the real cursor should
        // be modified, the inset's dispatch has to do so explicitly.
        if (!inset || !cur.result().dispatched())
                cur.dispatch(cmd);

        cur.endUndoGroup();

        // Notify left insets
        if (cur != old) {
                old.fixIfBroken();
                bool badcursor = notifyCursorLeaves(old, cur);
                if (badcursor)
                        cursor().fixIfBroken();
        }
        
        // Do we have a selection?
        theSelection().haveSelection(cursor().selection());

        // If the command has been dispatched,
        if (cur.result().dispatched() || cur.result().update())
                processUpdateFlags(cur.result().update());
}


void BufferView::lfunScroll(FuncRequest const & cmd)
{
        string const scroll_type = cmd.getArg(0);
        int const scroll_step = 
                (scroll_type == "line") ? d->scrollbarParameters_.single_step
                : (scroll_type == "page") ? d->scrollbarParameters_.page_step : 0;
        if (scroll_step == 0)
                return;
        string const scroll_quantity = cmd.getArg(1);
        if (scroll_quantity == "up")
                scrollUp(scroll_step);
        else if (scroll_quantity == "down")
                scrollDown(scroll_step);
        else {
                int const scroll_value = convert<int>(scroll_quantity);
                if (scroll_value)
                        scroll(scroll_step * scroll_value);
        }
        updateMetrics();
        buffer_.changed();
}


int BufferView::scroll(int y)
{
        if (y > 0)
                return scrollDown(y);
        if (y < 0)
                return scrollUp(-y);
        return 0;
}


int BufferView::scrollDown(int offset)
{
        Text * text = &buffer_.text();
        TextMetrics & tm = d->text_metrics_[text];
        int ymax = height_ + offset;
        while (true) {
                pair<pit_type, ParagraphMetrics const *> last = tm.last();
                int bottom_pos = last.second->position() + last.second->descent();
                if (last.first + 1 == int(text->paragraphs().size())) {
                        if (bottom_pos <= height_)
                                return 0;
                        offset = min(offset, bottom_pos - height_);
                        break;
                }
                if (bottom_pos > ymax)
                        break;
                tm.newParMetricsDown();
        }
        d->anchor_ypos_ -= offset;
        return -offset;
}


int BufferView::scrollUp(int offset)
{
        Text * text = &buffer_.text();
        TextMetrics & tm = d->text_metrics_[text];
        int ymin = - offset;
        while (true) {
                pair<pit_type, ParagraphMetrics const *> first = tm.first();
                int top_pos = first.second->position() - first.second->ascent();
                if (first.first == 0) {
                        if (top_pos >= 0)
                                return 0;
                        offset = min(offset, - top_pos);
                        break;
                }
                if (top_pos < ymin)
                        break;
                tm.newParMetricsUp();
        }
        d->anchor_ypos_ += offset;
        return offset;
}


void BufferView::setCursorFromRow(int row)
{
        int tmpid = -1;
        int tmppos = -1;

        buffer_.texrow().getIdFromRow(row, tmpid, tmppos);

        d->cursor_.reset(buffer_.inset());
        if (tmpid == -1)
                buffer_.text().setCursor(d->cursor_, 0, 0);
        else
                buffer_.text().setCursor(d->cursor_, buffer_.getParFromID(tmpid).pit(), tmppos);
}


bool BufferView::setCursorFromInset(Inset const * inset)
{
        // are we already there?
        if (cursor().nextInset() == inset)
                return true;

        // Inset is not at cursor position. Find it in the document.
        Cursor cur(*this);
        cur.reset(buffer().inset());
        while (cur && cur.nextInset() != inset)
                cur.forwardInset();

        if (cur) {
                setCursor(cur);
                return true;
        }
        return false;
}


void BufferView::gotoLabel(docstring const & label)
{
        Toc & toc = buffer().tocBackend().toc("label");
        TocIterator toc_it = toc.begin();
        TocIterator end = toc.end();
        for (; toc_it != end; ++toc_it) {
                if (label == toc_it->str())
                        dispatch(toc_it->action());
        }
        //FIXME: We could do a bit more searching thanks to this:
        //InsetLabel const * inset = buffer_.insetLabel(label);
}


TextMetrics const & BufferView::textMetrics(Text const * t) const
{
        return const_cast<BufferView *>(this)->textMetrics(t);
}


TextMetrics & BufferView::textMetrics(Text const * t)
{
        TextMetricsCache::iterator tmc_it  = d->text_metrics_.find(t);
        if (tmc_it == d->text_metrics_.end()) {
                tmc_it = d->text_metrics_.insert(
                        make_pair(t, TextMetrics(this, const_cast<Text *>(t)))).first;
        }
        return tmc_it->second;
}


ParagraphMetrics const & BufferView::parMetrics(Text const * t,
                pit_type pit) const
{
        return textMetrics(t).parMetrics(pit);
}


int BufferView::workHeight() const
{
        return height_;
}


void BufferView::setCursor(DocIterator const & dit)
{
        size_t const n = dit.depth();
        for (size_t i = 0; i < n; ++i)
                dit[i].inset().edit(d->cursor_, true);

        d->cursor_.setCursor(dit);
        d->cursor_.setSelection(false);
}


bool BufferView::checkDepm(Cursor & cur, Cursor & old)
{
        // Would be wrong to delete anything if we have a selection.
        if (cur.selection())
                return false;

        bool need_anchor_change = false;
        bool changed = d->cursor_.text()->deleteEmptyParagraphMechanism(cur, old,
                need_anchor_change);

        if (need_anchor_change)
                cur.resetAnchor();

        if (!changed)
                return false;

        d->cursor_ = cur;

        updateLabels(buffer_);

        updateMetrics();
        buffer_.changed();
        return true;
}


bool BufferView::mouseSetCursor(Cursor & cur, bool select)
{
        LASSERT(&cur.bv() == this, /**/);

        if (!select)
                // this event will clear selection so we save selection for
                // persistent selection
                cap::saveSelection(cursor());

        // Has the cursor just left the inset?
        bool badcursor = false;
        bool leftinset = (&d->cursor_.inset() != &cur.inset());
        if (leftinset) {
                d->cursor_.fixIfBroken();
                badcursor = notifyCursorLeaves(d->cursor_, cur);
                if (badcursor)
                        cur.fixIfBroken();
        }

        // FIXME: shift-mouse selection doesn't work well across insets.
        bool do_selection = select && &d->cursor_.anchor().inset() == &cur.inset();

        // do the dEPM magic if needed
        // FIXME: (1) move this to InsetText::notifyCursorLeaves?
        // FIXME: (2) if we had a working InsetText::notifyCursorLeaves,
        // the leftinset bool would not be necessary (badcursor instead).
        bool update = leftinset;
        if (!do_selection && !badcursor && d->cursor_.inTexted())
                update |= checkDepm(cur, d->cursor_);

        d->cursor_.setCursor(cur);
        d->cursor_.boundary(cur.boundary());
        if (do_selection)
                d->cursor_.setSelection();
        else
                d->cursor_.clearSelection();

        d->cursor_.finishUndo();
        d->cursor_.setCurrentFont();
        return update;
}


void BufferView::putSelectionAt(DocIterator const & cur,
                                int length, bool backwards)
{
        d->cursor_.clearSelection();

        setCursor(cur);

        if (length) {
                if (backwards) {
                        d->cursor_.pos() += length;
                        d->cursor_.setSelection(d->cursor_, -length);
                } else
                        d->cursor_.setSelection(d->cursor_, length);
        }
        // Ensure a redraw happens in any case because the new selection could 
        // possibly be on the same screen as the previous selection.
        processUpdateFlags(Update::Force | Update::FitCursor);
}


Cursor & BufferView::cursor()
{
        return d->cursor_;
}


Cursor const & BufferView::cursor() const
{
        return d->cursor_;
}


pit_type BufferView::anchor_ref() const
{
        return d->anchor_pit_;
}


bool BufferView::singleParUpdate()
{
        Text & buftext = buffer_.text();
        pit_type const bottom_pit = d->cursor_.bottom().pit();
        TextMetrics & tm = textMetrics(&buftext);
        int old_height = tm.parMetrics(bottom_pit).height();

        // make sure inline completion pointer is ok
        if (d->inlineCompletionPos_.fixIfBroken())
                d->inlineCompletionPos_ = DocIterator();

        // In Single Paragraph mode, rebreak only
        // the (main text, not inset!) paragraph containing the cursor.
        // (if this paragraph contains insets etc., rebreaking will
        // recursively descend)
        tm.redoParagraph(bottom_pit);
        ParagraphMetrics const & pm = tm.parMetrics(bottom_pit);                
        if (pm.height() != old_height)
                // Paragraph height has changed so we cannot proceed to
                // the singlePar optimisation.
                return false;

        d->update_strategy_ = SingleParUpdate;

        LYXERR(Debug::PAINTING, "\ny1: " << pm.position() - pm.ascent()
                << " y2: " << pm.position() + pm.descent()
                << " pit: " << bottom_pit
                << " singlepar: 1");
        return true;
}


void BufferView::updateMetrics()
{
        if (height_ == 0 || width_ == 0)
                return;

        Text & buftext = buffer_.text();
        pit_type const npit = int(buftext.paragraphs().size());

        // Clear out the position cache in case of full screen redraw,
        d->coord_cache_.clear();

        // Clear out paragraph metrics to avoid having invalid metrics
        // in the cache from paragraphs not relayouted below
        // The complete text metrics will be redone.
        d->text_metrics_.clear();

        TextMetrics & tm = textMetrics(&buftext);

        // make sure inline completion pointer is ok
        if (d->inlineCompletionPos_.fixIfBroken())
                d->inlineCompletionPos_ = DocIterator();
        
        if (d->anchor_pit_ >= npit)
                // The anchor pit must have been deleted...
                d->anchor_pit_ = npit - 1;

        // Rebreak anchor paragraph.
        tm.redoParagraph(d->anchor_pit_);
        ParagraphMetrics & anchor_pm = tm.par_metrics_[d->anchor_pit_];
        
        // position anchor
        if (d->anchor_pit_ == 0) {
                int scrollRange = d->scrollbarParameters_.max - d->scrollbarParameters_.min;
                
                // Complete buffer visible? Then it's easy.
                if (scrollRange == 0)
                        d->anchor_ypos_ = anchor_pm.ascent();
        
                // FIXME: Some clever handling needed to show
                // the _first_ paragraph up to the top if the cursor is
                // in the first line.
        }               
        anchor_pm.setPosition(d->anchor_ypos_);

        LYXERR(Debug::PAINTING, "metrics: "
                << " anchor pit = " << d->anchor_pit_
                << " anchor ypos = " << d->anchor_ypos_);

        // Redo paragraphs above anchor if necessary.
        int y1 = d->anchor_ypos_ - anchor_pm.ascent();
        // We are now just above the anchor paragraph.
        pit_type pit1 = d->anchor_pit_ - 1;
        for (; pit1 >= 0 && y1 >= 0; --pit1) {
                tm.redoParagraph(pit1);
                ParagraphMetrics & pm = tm.par_metrics_[pit1];
                y1 -= pm.descent();
                // Save the paragraph position in the cache.
                pm.setPosition(y1);
                y1 -= pm.ascent();
        }

        // Redo paragraphs below the anchor if necessary.
        int y2 = d->anchor_ypos_ + anchor_pm.descent();
        // We are now just below the anchor paragraph.
        pit_type pit2 = d->anchor_pit_ + 1;
        for (; pit2 < npit && y2 <= height_; ++pit2) {
                tm.redoParagraph(pit2);
                ParagraphMetrics & pm = tm.par_metrics_[pit2];
                y2 += pm.ascent();
                // Save the paragraph position in the cache.
                pm.setPosition(y2);
                y2 += pm.descent();
        }

        LYXERR(Debug::PAINTING, "Metrics: "
                << " anchor pit = " << d->anchor_pit_
                << " anchor ypos = " << d->anchor_ypos_
                << " y1 = " << y1
                << " y2 = " << y2
                << " pit1 = " << pit1
                << " pit2 = " << pit2);

        d->update_strategy_ = FullScreenUpdate;

        if (lyxerr.debugging(Debug::WORKAREA)) {
                LYXERR(Debug::WORKAREA, "BufferView::updateMetrics");
                d->coord_cache_.dump();
        }
}


void BufferView::insertLyXFile(FileName const & fname)
{
        LASSERT(d->cursor_.inTexted(), /**/);

        // Get absolute path of file and add ".lyx"
        // to the filename if necessary
        FileName filename = fileSearch(string(), fname.absFilename(), "lyx");

        docstring const disp_fn = makeDisplayPath(filename.absFilename());
        // emit message signal.
        message(bformat(_("Inserting document %1$s..."), disp_fn));

        docstring res;
        Buffer buf("", false);
        if (buf.loadLyXFile(filename)) {
                ErrorList & el = buffer_.errorList("Parse");
                // Copy the inserted document error list into the current buffer one.
                el = buf.errorList("Parse");
                buffer_.undo().recordUndo(d->cursor_);
                cap::pasteParagraphList(d->cursor_, buf.paragraphs(),
                                             buf.params().documentClassPtr(), el);
                res = _("Document %1$s inserted.");
        } else {
                res = _("Could not insert document %1$s");
        }

        updateMetrics();
        buffer_.changed();
        // emit message signal.
        message(bformat(res, disp_fn));
        buffer_.errors("Parse");
}


Point BufferView::coordOffset(DocIterator const & dit, bool boundary) const
{
        int x = 0;
        int y = 0;
        int lastw = 0;

        // Addup contribution of nested insets, from inside to outside,
        // keeping the outer paragraph for a special handling below
        for (size_t i = dit.depth() - 1; i >= 1; --i) {
                CursorSlice const & sl = dit[i];
                int xx = 0;
                int yy = 0;
                
                // get relative position inside sl.inset()
                sl.inset().cursorPos(*this, sl, boundary && (i + 1 == dit.depth()), xx, yy);
                
                // Make relative position inside of the edited inset relative to sl.inset()
                x += xx;
                y += yy;
                
                // In case of an RTL inset, the edited inset will be positioned to the left
                // of xx:yy
                if (sl.text()) {
                        bool boundary_i = boundary && i + 1 == dit.depth();
                        bool rtl = textMetrics(sl.text()).isRTL(sl, boundary_i);
                        if (rtl)
                                x -= lastw;
                }

                // remember width for the case that sl.inset() is positioned in an RTL inset
                if (i && dit[i - 1].text()) {
                        // If this Inset is inside a Text Inset, retrieve the Dimension
                        // from the containing text instead of using Inset::dimension() which
                        // might not be implemented.
                        // FIXME (Abdel 23/09/2007): this is a bit messy because of the
                        // elimination of Inset::dim_ cache. This coordOffset() method needs
                        // to be rewritten in light of the new design.
                        Dimension const & dim = parMetrics(dit[i - 1].text(),
                                dit[i - 1].pit()).insetDimension(&sl.inset());
                        lastw = dim.wid;
                } else {
                        Dimension const dim = sl.inset().dimension(*this);
                        lastw = dim.wid;
                }
                
                //lyxerr << "Cursor::getPos, i: "
                // << i << " x: " << xx << " y: " << y << endl;
        }

        // Add contribution of initial rows of outermost paragraph
        CursorSlice const & sl = dit[0];
        TextMetrics const & tm = textMetrics(sl.text());
        ParagraphMetrics const & pm = tm.parMetrics(sl.pit());
        LASSERT(!pm.rows().empty(), /**/);
        y -= pm.rows()[0].ascent();
#if 1
        // FIXME: document this mess
        size_t rend;
        if (sl.pos() > 0 && dit.depth() == 1) {
                int pos = sl.pos();
                if (pos && boundary)
                        --pos;
//              lyxerr << "coordOffset: boundary:" << boundary << " depth:" << dit.depth() << " pos:" << pos << " sl.pos:" << sl.pos() << endl;
                rend = pm.pos2row(pos);
        } else
                rend = pm.pos2row(sl.pos());
#else
        size_t rend = pm.pos2row(sl.pos());
#endif
        for (size_t rit = 0; rit != rend; ++rit)
                y += pm.rows()[rit].height();
        y += pm.rows()[rend].ascent();
        
        TextMetrics const & bottom_tm = textMetrics(dit.bottom().text());
        
        // Make relative position from the nested inset now bufferview absolute.
        int xx = bottom_tm.cursorX(dit.bottom(), boundary && dit.depth() == 1);
        x += xx;
        
        // In the RTL case place the nested inset at the left of the cursor in 
        // the outer paragraph
        bool boundary_1 = boundary && 1 == dit.depth();
        bool rtl = bottom_tm.isRTL(dit.bottom(), boundary_1);
        if (rtl)
                x -= lastw;
        
        return Point(x, y);
}


Point BufferView::getPos(DocIterator const & dit, bool boundary) const
{
        CursorSlice const & bot = dit.bottom();
        TextMetrics const & tm = textMetrics(bot.text());
        if (!tm.contains(bot.pit()))
                return Point(-1, -1);

        Point p = coordOffset(dit, boundary); // offset from outer paragraph
        p.y_ += tm.parMetrics(bot.pit()).position();
        return p;
}


void BufferView::draw(frontend::Painter & pain)
{
        if (height_ == 0 || width_ == 0)
                return;
        LYXERR(Debug::PAINTING, "\t\t*** START DRAWING ***");
        Text & text = buffer_.text();
        TextMetrics const & tm = d->text_metrics_[&text];
        int const y = tm.first().second->position();
        PainterInfo pi(this, pain);

        switch (d->update_strategy_) {

        case NoScreenUpdate:
                // If no screen painting is actually needed, only some the different
                // coordinates of insets and paragraphs needs to be updated.
                pi.full_repaint = true;
                pi.pain.setDrawingEnabled(false);
                tm.draw(pi, 0, y);
                break;

        case SingleParUpdate:
                pi.full_repaint = false;
                // In general, only the current row of the outermost paragraph
                // will be redrawn. Particular cases where selection spans
                // multiple paragraph are correctly detected in TextMetrics.
                tm.draw(pi, 0, y);
                break;

        case DecorationUpdate:
                // FIXME: We should also distinguish DecorationUpdate to avoid text
                // drawing if possible. This is not possible to do easily right now
                // because of the single backing pixmap.

        case FullScreenUpdate:
                // The whole screen, including insets, will be refreshed.
                pi.full_repaint = true;

                // Clear background.
                pain.fillRectangle(0, 0, width_, height_,
                        buffer_.inset().backgroundColor());

                // Draw everything.
                tm.draw(pi, 0, y);

                // and possibly grey out below
                pair<pit_type, ParagraphMetrics const *> lastpm = tm.last();
                int const y2 = lastpm.second->position() + lastpm.second->descent();
                if (y2 < height_)
                        pain.fillRectangle(0, y2, width_, height_ - y2, Color_bottomarea);
                break;
        }
        LYXERR(Debug::PAINTING, "\n\t\t*** END DRAWING  ***");

        // The scrollbar needs an update.
        updateScrollbar();

        // Normalize anchor for next time
        pair<pit_type, ParagraphMetrics const *> firstpm = tm.first();
        pair<pit_type, ParagraphMetrics const *> lastpm = tm.last();
        for (pit_type pit = firstpm.first; pit <= lastpm.first; ++pit) {
                ParagraphMetrics const & pm = tm.parMetrics(pit);
                if (pm.position() + pm.descent() > 0) {
                        d->anchor_pit_ = pit;
                        d->anchor_ypos_ = pm.position();
                        break;
                }
        }
        LYXERR(Debug::PAINTING, "Found new anchor pit = " << d->anchor_pit_
                << "  anchor ypos = " << d->anchor_ypos_);
}


void BufferView::message(docstring const & msg)
{
        if (d->gui_)
                d->gui_->message(msg);
}


void BufferView::showDialog(string const & name)
{
        if (d->gui_)
                d->gui_->showDialog(name, string());
}


void BufferView::showDialog(string const & name,
        string const & data, Inset * inset)
{
        if (d->gui_)
                d->gui_->showDialog(name, data, inset);
}


void BufferView::updateDialog(string const & name, string const & data)
{
        if (d->gui_)
                d->gui_->updateDialog(name, data);
}


void BufferView::setGuiDelegate(frontend::GuiBufferViewDelegate * gui)
{
        d->gui_ = gui;
}


// FIXME: Move this out of BufferView again
docstring BufferView::contentsOfPlaintextFile(FileName const & fname)
{
        if (!fname.isReadableFile()) {
                docstring const error = from_ascii(strerror(errno));
                docstring const file = makeDisplayPath(fname.absFilename(), 50);
                docstring const text =
                  bformat(_("Could not read the specified document\n"
                            "%1$s\ndue to the error: %2$s"), file, error);
                Alert::error(_("Could not read file"), text);
                return docstring();
        }

        if (!fname.isReadableFile()) {
                docstring const file = makeDisplayPath(fname.absFilename(), 50);
                docstring const text =
                  bformat(_("%1$s\n is not readable."), file);
                Alert::error(_("Could not open file"), text);
                return docstring();
        }

        // FIXME UNICODE: We don't know the encoding of the file
        docstring file_content = fname.fileContents("UTF-8");
        if (file_content.empty()) {
                Alert::error(_("Reading not UTF-8 encoded file"),
                             _("The file is not UTF-8 encoded.\n"
                               "It will be read as local 8Bit-encoded.\n"
                               "If this does not give the correct result\n"
                               "then please change the encoding of the file\n"
                               "to UTF-8 with a program other than LyX.\n"));
                file_content = fname.fileContents("local8bit");
        }

        return normalize_c(file_content);
}


void BufferView::insertPlaintextFile(FileName const & f, bool asParagraph)
{
        docstring const tmpstr = contentsOfPlaintextFile(f);

        if (tmpstr.empty())
                return;

        Cursor & cur = cursor();
        cap::replaceSelection(cur);
        buffer_.undo().recordUndo(cur);
        if (asParagraph)
                cur.innerText()->insertStringAsParagraphs(cur, tmpstr);
        else
                cur.innerText()->insertStringAsLines(cur, tmpstr);

        updateMetrics();
        buffer_.changed();
}


docstring const & BufferView::inlineCompletion() const
{
        return d->inlineCompletion_;
}


size_t const & BufferView::inlineCompletionUniqueChars() const
{
        return d->inlineCompletionUniqueChars_;
}


DocIterator const & BufferView::inlineCompletionPos() const
{
        return d->inlineCompletionPos_;
}


bool samePar(DocIterator const & a, DocIterator const & b)
{
        if (a.empty() && b.empty())
                return true;
        if (a.empty() || b.empty())
                return false;
        return &a.innerParagraph() == &b.innerParagraph();
}


void BufferView::setInlineCompletion(Cursor & cur, DocIterator const & pos, 
        docstring const & completion, size_t uniqueChars)
{
        uniqueChars = min(completion.size(), uniqueChars);
        bool changed = d->inlineCompletion_ != completion
                || d->inlineCompletionUniqueChars_ != uniqueChars;
        bool singlePar = true;
        d->inlineCompletion_ = completion;
        d->inlineCompletionUniqueChars_ = min(completion.size(), uniqueChars);
        
        //lyxerr << "setInlineCompletion pos=" << pos << " completion=" << completion << " uniqueChars=" << uniqueChars << std::endl;
        
        // at new position?
        DocIterator const & old = d->inlineCompletionPos_;
        if (old != pos) {
                //lyxerr << "inlineCompletionPos changed" << std::endl;
                // old or pos are in another paragraph?
                if ((!samePar(cur, pos) && !pos.empty())
                    || (!samePar(cur, old) && !old.empty())) {
                        singlePar = false;
                        //lyxerr << "different paragraph" << std::endl;
                }
                d->inlineCompletionPos_ = pos;
        }
        
        // set update flags
        if (changed) {
                if (singlePar && !(cur.disp_.update() & Update::Force))
                        cur.updateFlags(cur.disp_.update() | Update::SinglePar);
                else
                        cur.updateFlags(cur.disp_.update() | Update::Force);
        }
}

} // namespace lyx