/* This file is part of
 * ======================================================
 * 
 *           LyX, The Document Processor
 * 	 
 *           Copyright 1995-2001 The LyX Team.
 *
 * ====================================================== */

#include <config.h>

#include "CutAndPaste.h"
#include "BufferView.h"
#include "buffer.h"
#include "paragraph.h"
#include "insets/inseterror.h"
#include "lyx_gui_misc.h"
#include "lyxcursor.h"
#include "gettext.h"

#ifdef __GNUG__
#pragma implementation
#endif

using std::pair;

extern BufferView * current_view;

// Jürgen, note that this means that you cannot currently have a list
// of selections cut/copied. So IMHO later we should have a
// list/vector/deque that we could store
// struct selection_item {
//       Paragraph * buf;
//       LyXTextClassList::size_type textclass;
// };
// in and some method of choosing beween them (based on the first few chars
// in the selection probably.) This would be a nice feature and quite
// easy to implement. (Lgb)
//
// Sure but I just cleaned up this code for now with the same functionality
// as before. I also want to add a XClipboard function so that we can copy
// text from LyX to some other X-application in the form of ASCII or in the
// form of LaTeX (or Docbook depending on the document-class!). Think how nice
// it could be to select a math-inset do a "Copy to X-Clipboard as LaTeX" and
// then do a middle mouse button click in the application you want and have
// the whole formula there in LaTeX-Code. (Jug)

namespace {

Paragraph * buf = 0;
LyXTextClassList::size_type textclass = 0;

// for now here this should be in another Cut&Paste Class!
// Jürgen, I moved this out of CutAndPaste since it does not operate on any
// member of the CutAndPaste class and in addition it was private.
// Perhaps it even should take a parameter? (Lgb)
void DeleteBuffer()
{
	if (!buf)
		return;
	
	Paragraph * tmppar;
	
	while (buf) {
		tmppar =  buf;
		buf = buf->next();
		delete tmppar;
	}
	buf = 0;
}

} // namespace anon


bool CutAndPaste::cutSelection(Paragraph * startpar, Paragraph ** endpar,
                               int start, int & end, char tc, bool doclear,
							   bool realcut)
{
	if (!startpar || (start > startpar->size()))
		return false;
	
	if (realcut)
		DeleteBuffer();
	
	textclass = tc;
	
	if (!(*endpar) || startpar == (*endpar)) {
		// only within one paragraph
		if (realcut)
			buf = new Paragraph;
		Paragraph::size_type i = start;
		if (end > startpar->size())
			end = startpar->size();
		for (; i < end; ++i) {
			if (realcut)
				startpar->copyIntoMinibuffer(*current_view->buffer(),
				                             start);
			startpar->erase(start);
			if (realcut)
				buf->insertFromMinibuffer(buf->size());
		}
		end = start - 1;
	} else {
		// more than one paragraph
		(*endpar)->breakParagraphConservative(current_view->buffer()->params,
		                                      end);
		*endpar = (*endpar)->next();
		end = 0;
		
		startpar->breakParagraphConservative(current_view->buffer()->params,
		                                     start);
		
		// store the selection
		if (realcut) {
			buf = startpar->next();
			buf->previous(0);
		} else {
			startpar->next()->previous(0);
		}
		(*endpar)->previous()->next(0);
		
		// cut the selection
		startpar->next(*endpar);
		
		(*endpar)->previous(startpar);
		
		// the cut selection should begin with standard layout
		if (realcut)
			buf->clear(); 
		
		// paste the paragraphs again, if possible
		if (doclear)
			startpar->next()->stripLeadingSpaces(textclass);
		if (startpar->hasSameLayout(startpar->next()) ||
		    !startpar->next()->size()) {
			startpar->pasteParagraph(current_view->buffer()->params);
			(*endpar) = startpar; // this because endpar gets deleted here!
		}
	}
	return true;
}


bool CutAndPaste::copySelection(Paragraph * startpar, Paragraph * endpar,
				int start, int end, char tc)
{
	if (!startpar || (start > startpar->size()))
		return false;
	
	DeleteBuffer();
	
	textclass = tc;
	
	if (!endpar ||
	    startpar == endpar) {
		// only within one paragraph
		buf = new Paragraph;
		Paragraph::size_type i = start;
		if (end > startpar->size())
			end = startpar->size();
		for (; i < end; ++i) {
			startpar->copyIntoMinibuffer(*current_view->buffer(), i);
			buf->insertFromMinibuffer(buf->size());
		}
	} else {
		// copy more than one paragraph
		// clone the paragraphs within the selection
		Paragraph * tmppar = startpar;
		buf = new Paragraph(*tmppar, false);
		Paragraph * tmppar2 = buf;
		
		while (tmppar != endpar
		       && tmppar->next()) {
			tmppar = tmppar->next();
			tmppar2->next(new Paragraph(*tmppar, false));
			tmppar2->next()->previous(tmppar2);
			tmppar2 = tmppar2->next();
		}
		tmppar2->next(0);
		
		// the buf paragraph is too big
		Paragraph::size_type tmpi2 = start;
		for (; tmpi2; --tmpi2)
			buf->erase(0);
		
		// now tmppar 2 is too big, delete all after end
		tmpi2 = end;
		while (tmppar2->size() > tmpi2) {
			tmppar2->erase(tmppar2->size() - 1);
		}
	}
	return true;
}


bool CutAndPaste::pasteSelection(Paragraph ** par, Paragraph ** endpar,
                                 int & pos, char tc)
{
	if (!checkPastePossible(*par))
		return false;
	
	if (pos > (*par)->size())
		pos = (*par)->size();
	
	// Paragraph * tmpbuf;
	Paragraph * tmppar = *par;
	int tmppos = pos;
	
	// There are two cases: cutbuffer only one paragraph or many
	if (!buf->next()) {
		// only within a paragraph
		Paragraph * tmpbuf = new Paragraph(*buf, false);
		
		// Some provisions should be done here for checking
		// if we are inserting at the beginning of a
		// paragraph. If there are a space at the beginning
		// of the text to insert and we are inserting at
		// the beginning of the paragraph the space should
		// be removed.
		while (buf->size()) {
			// This is an attempt to fix the
			// "never insert a space at the
			// beginning of a paragraph" problem.
			if (!tmppos && buf->isLineSeparator(0)) {
				buf->erase(0);
			} else {
				buf->cutIntoMinibuffer(current_view->buffer()->params, 0);
				buf->erase(0);
				if (tmppar->insertFromMinibuffer(tmppos))
					++tmppos;
			}
		}
		delete buf;
		buf = tmpbuf;
		*endpar = tmppar->next();
		pos = tmppos;
	} else {
		// many paragraphs
		
		// make a copy of the simple cut_buffer
		Paragraph * tmpbuf = buf;
		Paragraph * simple_cut_clone = new Paragraph(*tmpbuf, false);
		Paragraph * tmpbuf2 = simple_cut_clone;
		
		while (tmpbuf->next()) {
			tmpbuf = tmpbuf->next();
			tmpbuf2->next(new Paragraph(*tmpbuf, false));
			tmpbuf2->next()->previous(tmpbuf2);
			tmpbuf2 = tmpbuf2->next();
		}
		
		// make sure there is no class difference
		SwitchLayoutsBetweenClasses(textclass, tc, buf);
		
		// make the buf exactly the same layout than
		// the cursor paragraph
		buf->makeSameLayout(*par);
		
		// find the end of the buffer
		Paragraph * lastbuffer = buf;
		while (lastbuffer->next())
			lastbuffer = lastbuffer->next();
		
		bool paste_the_end = false;
		
		// open the paragraph for inserting the buf
		// if necessary
		if (((*par)->size() > pos) || !(*par)->next()) {
			(*par)->breakParagraphConservative(current_view->buffer()->params,
							   pos);
			paste_the_end = true;
		}
		// set the end for redoing later
		*endpar = (*par)->next()->next();
		
		// paste it!
		lastbuffer->next((*par)->next());
		(*par)->next()->previous(lastbuffer);
		
		(*par)->next(buf);
		buf->previous(*par);
		
		if ((*par)->next() == lastbuffer)
			lastbuffer = *par;
		
		(*par)->pasteParagraph(current_view->buffer()->params);
		// store the new cursor position
		*par = lastbuffer;
		pos = lastbuffer->size();
		// maybe some pasting
		if (lastbuffer->next() && paste_the_end) {
			if (lastbuffer->next()->hasSameLayout(lastbuffer)) {
				lastbuffer->pasteParagraph(current_view->buffer()->params);
			} else if (!lastbuffer->next()->size()) {
				lastbuffer->next()->makeSameLayout(lastbuffer);
				lastbuffer->pasteParagraph(current_view->buffer()->params);
			} else if (!lastbuffer->size()) {
				lastbuffer->makeSameLayout(lastbuffer->next());
				lastbuffer->pasteParagraph(current_view->buffer()->params);
			} else
				lastbuffer->next()->stripLeadingSpaces(tc);
		}
		// restore the simple cut buffer
		buf = simple_cut_clone;
	}
	
	return true;
}


int CutAndPaste::nrOfParagraphs()
{
	if (!buf)
		return 0;
	
	int n = 1;
	Paragraph * tmppar = buf;
	while(tmppar->next()) {
		++n;
		tmppar = tmppar->next();
	}
	return n;
}


int CutAndPaste::SwitchLayoutsBetweenClasses(LyXTextClassList::size_type c1,
					     LyXTextClassList::size_type c2,
					     Paragraph * par)
{
	int ret = 0;
	if (!par || c1 == c2)
		return ret;
	
	while (par) {
		string const name = textclasslist.NameOfLayout(c1,
							       par->layout);
		int lay = 0;
		pair<bool, LyXTextClass::LayoutList::size_type> pp =
			textclasslist.NumberOfLayout(c2, name);
		if (pp.first) {
			lay = pp.second;
		} else { // layout not found
			// use default layout "Standard" (0)
			lay = 0;
		}
		par->layout = lay;
		
		if (name != textclasslist.NameOfLayout(c2, par->layout)) {
			++ret;
			string const s = _("Layout had to be changed from\n")
				+ name + _(" to ")
				+ textclasslist.NameOfLayout(c2, par->layout)
				+ _("\nbecause of class conversion from\n")
				+ textclasslist.NameOfClass(c1) + _(" to ")
				+ textclasslist.NameOfClass(c2);
			InsetError * new_inset = new InsetError(s);
			par->insertInset(0, new_inset);
		}
		par = par->next();
	}
	return ret;
}


bool CutAndPaste::checkPastePossible(Paragraph *)
{
	if (!buf) return false;
	
	return true;
}