/* text.c
 *
 *
 * $Id$
 *
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/blenkernel/intern/text.c
 *  \ingroup bke
 */


#include <string.h> /* strstr */
#include <sys/types.h>
#include <sys/stat.h>

#include "MEM_guardedalloc.h"

#include "BLI_blenlib.h"
#include "BLI_utildefines.h"

#include "DNA_constraint_types.h"
#include "DNA_controller_types.h"
#include "DNA_scene_types.h"
#include "DNA_screen_types.h"
#include "DNA_space_types.h"
#include "DNA_text_types.h"
#include "DNA_userdef_types.h"
#include "DNA_object_types.h"

#include "BKE_depsgraph.h"
#include "BKE_global.h"
#include "BKE_library.h"
#include "BKE_main.h"
#include "BKE_text.h"


#ifdef WITH_PYTHON
#include "BPY_extern.h"
#endif

/***************/ /*

How Texts should work
--
A text should relate to a file as follows -
(Text *)->name should be the place where the 
	file will or has been saved.
	
(Text *)->flags has the following bits
	TXT_ISDIRTY - should always be set if the file in mem. differs from
					the file on disk, or if there is no file on disk.
	TXT_ISMEM - should always be set if the Text has not been mapped to
					a file, in which case (Text *)->name may be NULL or garbage.			
	TXT_ISEXT - should always be set if the Text is not to be written into
					the .blend
	TXT_ISSCRIPT - should be set if the user has designated the text
					as a script. (NEW: this was unused, but now it is needed by
					space handler script links (see header_view3d.c, for example)

->>> see also: /makesdna/DNA_text_types.h

Display
--
The st->top determines at what line the top of the text is displayed.
If the user moves the cursor the st containing that cursor should
be popped ... other st's retain their own top location.

Markers
--
The mrk->flags define the behaviour and relationships between markers. The
upper two bytes are used to hold a group ID, the lower two are normal flags. If
TMARK_EDITALL is set the group ID defines which other markers should be edited.

The mrk->clr field is used to visually group markers where the flags may not
match. A template system, for example, may allow editing of repeating tokens
(in one group) but include other marked positions (in another group) all in the
same template with the same color.

Undo
--
Undo/Redo works by storing
events in a queue, and a pointer
to the current position in the
queue...

Events are stored using an
arbitrary op-code system
to keep track of
a) the two cursors (normal and selected)
b) input (visible and control (ie backspace))

input data is stored as its
ASCII value, the opcodes are
then selected to not conflict.

opcodes with data in between are
written at the beginning and end
of the data to allow undo and redo
to simply check the code at the current
undo position

*/ /***************/

/***/

static void txt_pop_first(Text *text);
static void txt_pop_last(Text *text);
static void txt_undo_add_op(Text *text, int op);
static void txt_undo_add_block(Text *text, int op, const char *buf);
static void txt_delete_line(Text *text, TextLine *line);
static void txt_delete_sel (Text *text);
static void txt_make_dirty (Text *text);

/***/

static unsigned char undoing;

/* allow to switch off undoing externally */
void txt_set_undostate(int u)
{
	undoing = u;
}

int txt_get_undostate(void)
{
	return undoing;
}

static void init_undo_text(Text *text)
{
	text->undo_pos= -1;
	text->undo_len= TXT_INIT_UNDO;
	text->undo_buf= MEM_mallocN(text->undo_len, "undo buf");
}

void free_text(Text *text)
{
	TextLine *tmp;

	for (tmp= text->lines.first; tmp; tmp= tmp->next) {
		MEM_freeN(tmp->line);
		if (tmp->format)
		  MEM_freeN(tmp->format);
	}
	
	BLI_freelistN(&text->lines);
	BLI_freelistN(&text->markers);

	if(text->name) MEM_freeN(text->name);
	MEM_freeN(text->undo_buf);
#ifdef WITH_PYTHON
	if (text->compiled) BPY_text_free_code(text);
#endif
}

Text *add_empty_text(const char *name) 
{
	Main *bmain= G.main;
	Text *ta;
	TextLine *tmp;
	
	ta= alloc_libblock(&bmain->text, ID_TXT, name);
	ta->id.us= 1;
	
	ta->name= NULL;

	init_undo_text(ta);

	ta->nlines=1;
	ta->flags= TXT_ISDIRTY | TXT_ISMEM;
	if((U.flag & USER_TXT_TABSTOSPACES_DISABLE)==0)
		ta->flags |= TXT_TABSTOSPACES;

	ta->lines.first= ta->lines.last= NULL;
	ta->markers.first= ta->markers.last= NULL;

	tmp= (TextLine*) MEM_mallocN(sizeof(TextLine), "textline");
	tmp->line= (char*) MEM_mallocN(1, "textline_string");
	tmp->format= NULL;
	
	tmp->line[0]=0;
	tmp->len= 0;
				
	tmp->next= NULL;
	tmp->prev= NULL;
				
	BLI_addhead(&ta->lines, tmp);
	
	ta->curl= ta->lines.first;
	ta->curc= 0;
	ta->sell= ta->lines.first;
	ta->selc= 0;

	return ta;
}

// this function removes any control characters from
// a textline

static void cleanup_textline(TextLine * tl)
{
	int i;

	for (i = 0; i < tl->len; i++ ) {
		if (tl->line[i] < ' ' && tl->line[i] != '\t') {
			memmove(tl->line + i, tl->line + i + 1, tl->len - i);
			tl->len--;
			i--;
		}
	}
}

int reopen_text(Text *text)
{
	FILE *fp;
	int i, llen, len, res;
	unsigned char *buffer;
	TextLine *tmp;
	char str[FILE_MAXDIR+FILE_MAXFILE];
	struct stat st;

	if (!text || !text->name) return 0;
	
	BLI_strncpy(str, text->name, FILE_MAXDIR+FILE_MAXFILE);
	BLI_path_abs(str, G.main->name);
	
	fp= fopen(str, "r");
	if(fp==NULL) return 0;

	/* free memory: */

	for (tmp= text->lines.first; tmp; tmp= tmp->next) {
		MEM_freeN(tmp->line);
		if (tmp->format) MEM_freeN(tmp->format);
	}
	
	BLI_freelistN(&text->lines);

	text->lines.first= text->lines.last= NULL;
	text->curl= text->sell= NULL;

	/* clear undo buffer */
	MEM_freeN(text->undo_buf);
	init_undo_text(text);
	
	fseek(fp, 0L, SEEK_END);
	len= ftell(fp);
	fseek(fp, 0L, SEEK_SET);	

	text->undo_pos= -1;
	
	buffer= MEM_mallocN(len, "text_buffer");
	// under windows fread can return less then len bytes because
	// of CR stripping
	len = fread(buffer, 1, len, fp);

	fclose(fp);

	res= stat(str, &st);
	text->mtime= st.st_mtime;
	
	text->nlines=0;
	llen=0;
	for(i=0; i<len; i++) {
		if (buffer[i]=='\n') {
			tmp= (TextLine*) MEM_mallocN(sizeof(TextLine), "textline");
			tmp->line= (char*) MEM_mallocN(llen+1, "textline_string");
			tmp->format= NULL;
			
			if(llen) memcpy(tmp->line, &buffer[i-llen], llen);
			tmp->line[llen]=0;
			tmp->len= llen;
				
			cleanup_textline(tmp);

			BLI_addtail(&text->lines, tmp);
			text->nlines++;
				
			llen=0;
			continue;
		}
		llen++;
	}

	if (llen!=0 || text->nlines==0) {
		tmp= (TextLine*) MEM_mallocN(sizeof(TextLine), "textline");
		tmp->line= (char*) MEM_mallocN(llen+1, "textline_string");
		tmp->format= NULL;
		
		if(llen) memcpy(tmp->line, &buffer[i-llen], llen);

		tmp->line[llen]=0;
		tmp->len= llen;
		
		cleanup_textline(tmp);

		BLI_addtail(&text->lines, tmp);
		text->nlines++;
	}
	
	text->curl= text->sell= text->lines.first;
	text->curc= text->selc= 0;
	
	MEM_freeN(buffer);	
	return 1;
}

Text *add_text(const char *file, const char *relpath) 
{
	Main *bmain= G.main;
	FILE *fp;
	int i, llen, len, res;
	unsigned char *buffer;
	TextLine *tmp;
	Text *ta;
	char str[FILE_MAXDIR+FILE_MAXFILE];
	struct stat st;

	BLI_strncpy(str, file, FILE_MAXDIR+FILE_MAXFILE);
	if (relpath) /* can be NULL (bg mode) */
		BLI_path_abs(str, relpath);
	
	fp= fopen(str, "r");
	if(fp==NULL) return NULL;
	
	ta= alloc_libblock(&bmain->text, ID_TXT, BLI_path_basename(str));
	ta->id.us= 1;

	ta->lines.first= ta->lines.last= NULL;
	ta->markers.first= ta->markers.last= NULL;
	ta->curl= ta->sell= NULL;

	if((U.flag & USER_TXT_TABSTOSPACES_DISABLE)==0)
		ta->flags= TXT_TABSTOSPACES;

	fseek(fp, 0L, SEEK_END);
	len= ftell(fp);
	fseek(fp, 0L, SEEK_SET);	

	ta->name= MEM_mallocN(strlen(file)+1, "text_name");
	strcpy(ta->name, file);

	init_undo_text(ta);
	
	buffer= MEM_mallocN(len, "text_buffer");
	// under windows fread can return less then len bytes because
	// of CR stripping
	len = fread(buffer, 1, len, fp);

	fclose(fp);

	res= stat(str, &st);
	ta->mtime= st.st_mtime;
	
	ta->nlines=0;
	llen=0;
	for(i=0; i<len; i++) {
		if (buffer[i]=='\n') {
			tmp= (TextLine*) MEM_mallocN(sizeof(TextLine), "textline");
			tmp->line= (char*) MEM_mallocN(llen+1, "textline_string");
			tmp->format= NULL;
			
			if(llen) memcpy(tmp->line, &buffer[i-llen], llen);
			tmp->line[llen]=0;
			tmp->len= llen;
			
			cleanup_textline(tmp);

			BLI_addtail(&ta->lines, tmp);
			ta->nlines++;
				
			llen=0;
			continue;
		}
		llen++;
	}

	if (llen!=0 || ta->nlines==0) {
		tmp= (TextLine*) MEM_mallocN(sizeof(TextLine), "textline");
		tmp->line= (char*) MEM_mallocN(llen+1, "textline_string");
		tmp->format= NULL;
		
		if(llen) memcpy(tmp->line, &buffer[i-llen], llen);

		tmp->line[llen]=0;
		tmp->len= llen;
		
		cleanup_textline(tmp);

		BLI_addtail(&ta->lines, tmp);
		ta->nlines++;
	}
	
	ta->curl= ta->sell= ta->lines.first;
	ta->curc= ta->selc= 0;
	
	MEM_freeN(buffer);	

	return ta;
}

Text *copy_text(Text *ta)
{
	Text *tan;
	TextLine *line, *tmp;
	
	tan= copy_libblock(ta);
	
	/* file name can be NULL */
	if(ta->name) {
		tan->name= MEM_mallocN(strlen(ta->name)+1, "text_name");
		strcpy(tan->name, ta->name);
	}
	else {
		tan->name= NULL;
	}

	tan->flags = ta->flags | TXT_ISDIRTY;
	
	tan->lines.first= tan->lines.last= NULL;
	tan->markers.first= tan->markers.last= NULL;
	tan->curl= tan->sell= NULL;
	
	tan->nlines= ta->nlines;

	line= ta->lines.first;	
	/* Walk down, reconstructing */
	while (line) {
		tmp= (TextLine*) MEM_mallocN(sizeof(TextLine), "textline");
		tmp->line= MEM_mallocN(line->len+1, "textline_string");
		tmp->format= NULL;
		
		strcpy(tmp->line, line->line);

		tmp->len= line->len;
		
		BLI_addtail(&tan->lines, tmp);
		
		line= line->next;
	}

	tan->curl= tan->sell= tan->lines.first;
	tan->curc= tan->selc= 0;

	init_undo_text(tan);

	return tan;
}

void unlink_text(Main *bmain, Text *text)
{
	bScreen *scr;
	ScrArea *area;
	SpaceLink *sl;
	Scene *scene;
	Object *ob;
	bController *cont;
	bConstraint *con;
	short update;

	/* dome */
	for(scene=bmain->scene.first; scene; scene=scene->id.next)
		if(scene->r.dometext == text)
			scene->r.dometext = NULL;

	for(ob=bmain->object.first; ob; ob=ob->id.next) {
		/* game controllers */
		for(cont=ob->controllers.first; cont; cont=cont->next) {
			if(cont->type==CONT_PYTHON) {
				bPythonCont *pc;
				
				pc= cont->data;
				if(pc->text==text) pc->text= NULL;
			}
		}

		/* pyconstraints */
		update = 0;

		if(ob->type==OB_ARMATURE && ob->pose) {
			bPoseChannel *pchan;
			for(pchan= ob->pose->chanbase.first; pchan; pchan= pchan->next) {
				for(con = pchan->constraints.first; con; con=con->next) {
					if(con->type==CONSTRAINT_TYPE_PYTHON) {
						bPythonConstraint *data = con->data;
						if (data->text==text) data->text = NULL;
						update = 1;
						
					}
				}
			}
		}

		for(con = ob->constraints.first; con; con=con->next) {
			if(con->type==CONSTRAINT_TYPE_PYTHON) {
				bPythonConstraint *data = con->data;
				if (data->text==text) data->text = NULL;
				update = 1;
			}
		}
		
		if(update)
			DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
	}

	/* pynodes */
	// XXX nodeDynamicUnlinkText(&text->id);
	
	/* text space */
	for(scr= bmain->screen.first; scr; scr= scr->id.next) {
		for(area= scr->areabase.first; area; area= area->next) {
			for(sl= area->spacedata.first; sl; sl= sl->next) {
				if(sl->spacetype==SPACE_TEXT) {
					SpaceText *st= (SpaceText*) sl;
					
					if(st->text==text) {
						st->text= NULL;
						st->top= 0;
					}
				}
			}
		}
	}

	text->id.us= 0;
}

void clear_text(Text *text) /* called directly from rna */
{
	int oldstate;

	oldstate = txt_get_undostate(  );
	txt_set_undostate( 1 );
	txt_sel_all( text );
	txt_delete_sel(text);
	txt_set_undostate( oldstate );

	txt_make_dirty(text);
}

void write_text(Text *text, const char *str) /* called directly from rna */
{
	int oldstate;

	oldstate = txt_get_undostate(  );
	txt_insert_buf( text, str );
	txt_move_eof( text, 0 );
	txt_set_undostate( oldstate );

	txt_make_dirty(text);
}

/*****************************/
/* Editing utility functions */
/*****************************/

static void make_new_line (TextLine *line, char *newline) 
{
	if (line->line) MEM_freeN(line->line);
	if (line->format) MEM_freeN(line->format);
	
	line->line= newline;
	line->len= strlen(newline);
	line->format= NULL;
}

static TextLine *txt_new_line(const char *str)
{
	TextLine *tmp;

	if(!str) str= "";
	
	tmp= (TextLine *) MEM_mallocN(sizeof(TextLine), "textline");
	tmp->line= MEM_mallocN(strlen(str)+1, "textline_string");
	tmp->format= NULL;
	
	strcpy(tmp->line, str);
	
	tmp->len= strlen(str);
	tmp->next= tmp->prev= NULL;
	
	return tmp;
}

static TextLine *txt_new_linen(const char *str, int n)
{
	TextLine *tmp;

	tmp= (TextLine *) MEM_mallocN(sizeof(TextLine), "textline");
	tmp->line= MEM_mallocN(n+1, "textline_string");
	tmp->format= NULL;
	
	BLI_strncpy(tmp->line, (str)? str: "", n+1);
	
	tmp->len= strlen(tmp->line);
	tmp->next= tmp->prev= NULL;
	
	return tmp;
}

void txt_clean_text (Text *text) 
{	
	TextLine **top, **bot;
	
	if (!text) return;
	
	if (!text->lines.first) {
		if (text->lines.last) text->lines.first= text->lines.last;
		else text->lines.first= text->lines.last= txt_new_line(NULL);
	} 
	
	if (!text->lines.last) text->lines.last= text->lines.first;

	top= (TextLine **) &text->lines.first;
	bot= (TextLine **) &text->lines.last;
	
	while ((*top)->prev) *top= (*top)->prev;
	while ((*bot)->next) *bot= (*bot)->next;

	if(!text->curl) {
		if(text->sell) text->curl= text->sell;
		else text->curl= text->lines.first;
		text->curc= 0;
	}

	if(!text->sell) {
		text->sell= text->curl;
		text->selc= 0;
	}
}

int txt_get_span (TextLine *from, TextLine *to)
{
	int ret=0;
	TextLine *tmp= from;

	if (!to || !from) return 0;
	if (from==to) return 0;

	/* Look forwards */
	while (tmp) {
		if (tmp == to) return ret;
		ret++;
		tmp= tmp->next;
	}

	/* Look backwards */
	if (!tmp) {
		tmp= from;
		ret=0;
		while(tmp) {
			if (tmp == to) break;
			ret--;
			tmp= tmp->prev;
		}
		if(!tmp) ret=0;
	}

	return ret;	
}

static void txt_make_dirty (Text *text)
{
	text->flags |= TXT_ISDIRTY;
#ifdef WITH_PYTHON
	if (text->compiled) BPY_text_free_code(text);
#endif
}

/* 0:whitespace, 1:punct, 2:alphanumeric */
static short txt_char_type (char ch)
{
	if (ch <= ' ') return 0; /* 32 */
	if (ch <= '/') return 1; /* 47 */
	if (ch <= '9') return 2; /* 57 */
	if (ch <= '@') return 1; /* 64 */
	if (ch <= 'Z') return 2; /* 90 */
	if (ch == '_') return 2; /* 95, dont delimit '_' */
	if (ch <= '`') return 1; /* 96 */
	if (ch <= 'z') return 2; /* 122 */
	return 1;
}

/****************************/
/* Cursor utility functions */
/****************************/

static void txt_curs_cur (Text *text, TextLine ***linep, int **charp)
{
	*linep= &text->curl; *charp= &text->curc;
}

static void txt_curs_sel (Text *text, TextLine ***linep, int **charp)
{
	*linep= &text->sell; *charp= &text->selc;
}

static void txt_curs_first (Text *text, TextLine **linep, int *charp)
{
	if (text->curl==text->sell) {
		*linep= text->curl;
		if (text->curc<text->selc) *charp= text->curc;
		else *charp= text->selc;
	} else if (txt_get_span(text->lines.first, text->curl)<txt_get_span(text->lines.first, text->sell)) {
		*linep= text->curl;
		*charp= text->curc;
	} else {
		*linep= text->sell;
		*charp= text->selc;		
	}
}

/****************************/
/* Cursor movement functions */
/****************************/

void txt_move_up(Text *text, short sel)
{
	TextLine **linep;
	int *charp, old;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else { txt_pop_first(text); txt_curs_cur(text, &linep, &charp); }
	if (!*linep) return;
	old= *charp;

	if((*linep)->prev) {
		*linep= (*linep)->prev;
		if (*charp > (*linep)->len) {
			*charp= (*linep)->len;
			if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, (*linep)->next), old, txt_get_span(text->lines.first, *linep), (unsigned short) *charp);
		} else {
			if(!undoing) txt_undo_add_op(text, sel?UNDO_SUP:UNDO_CUP);
		}
	} else {
		txt_move_bol(text, sel);
	}

	if(!sel) txt_pop_sel(text);
}

void txt_move_down(Text *text, short sel) 
{
	TextLine **linep;
	int *charp, old;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else { txt_pop_last(text); txt_curs_cur(text, &linep, &charp); }
	if (!*linep) return;
	old= *charp;

	if((*linep)->next) {
		*linep= (*linep)->next;
		if (*charp > (*linep)->len) {
			*charp= (*linep)->len;
			if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, (*linep)->prev), old, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
		} else
			if(!undoing) txt_undo_add_op(text, sel?UNDO_SDOWN:UNDO_CDOWN);	
	} else {
		txt_move_eol(text, sel);
	}

	if(!sel) txt_pop_sel(text);
}

void txt_move_left(Text *text, short sel) 
{
	TextLine **linep;
	int *charp, oundoing= undoing;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else { txt_pop_first(text); txt_curs_cur(text, &linep, &charp); }
	if (!*linep) return;

	undoing= 1;
	if (*charp== 0) {
		if ((*linep)->prev) {
			txt_move_up(text, sel);
			*charp= (*linep)->len;
		}
	} else {
		(*charp)--;
	}
	undoing= oundoing;
	if(!undoing) txt_undo_add_op(text, sel?UNDO_SLEFT:UNDO_CLEFT);
	
	if(!sel) txt_pop_sel(text);
}

void txt_move_right(Text *text, short sel) 
{
	TextLine **linep;
	int *charp, oundoing= undoing;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else { txt_pop_last(text); txt_curs_cur(text, &linep, &charp); }
	if (!*linep) return;

	undoing= 1;
	if (*charp== (*linep)->len) {
		if ((*linep)->next) {
			txt_move_down(text, sel);
			*charp= 0;
		}
	} else {
		(*charp)++;
	}
	undoing= oundoing;
	if(!undoing) txt_undo_add_op(text, sel?UNDO_SRIGHT:UNDO_CRIGHT);

	if(!sel) txt_pop_sel(text);
}

void txt_jump_left(Text *text, short sel)
{
	TextLine **linep, *oldl;
	int *charp, oldc, count, i;
	unsigned char oldu;

	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else { txt_pop_first(text); txt_curs_cur(text, &linep, &charp); }
	if (!*linep) return;

	oldl= *linep;
	oldc= *charp;
	oldu= undoing;
	undoing= 1; /* Don't push individual moves to undo stack */

	count= 0;
	for (i=0; i<3; i++) {
		if (count < 2) {
			while (*charp>0 && txt_char_type((*linep)->line[*charp-1])==i) {
				txt_move_left(text, sel);
				count++;
			}
		}
	}
	if (count==0) txt_move_left(text, sel);

	undoing= oldu;
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, oldl), oldc, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
}

void txt_jump_right(Text *text, short sel)
{
	TextLine **linep, *oldl;
	int *charp, oldc, count, i;
	unsigned char oldu;

	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else { txt_pop_last(text); txt_curs_cur(text, &linep, &charp); }
	if (!*linep) return;

	oldl= *linep;
	oldc= *charp;
	oldu= undoing;
	undoing= 1; /* Don't push individual moves to undo stack */

	count= 0;
	for (i=0; i<3; i++) {
		if (count < 2) {
			while (*charp<(*linep)->len && txt_char_type((*linep)->line[*charp])==i) {
				txt_move_right(text, sel);
				count++;
			}
		}
	}
	if (count==0) txt_move_right(text, sel);

	undoing= oldu;
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, oldl), oldc, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
}

void txt_move_bol (Text *text, short sel) 
{
	TextLine **linep;
	int *charp, old;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else txt_curs_cur(text, &linep, &charp);
	if (!*linep) return;
	old= *charp;
	
	*charp= 0;

	if(!sel) txt_pop_sel(text);
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, *linep), old, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
}

void txt_move_eol (Text *text, short sel) 
{
	TextLine **linep;
	int *charp, old;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else txt_curs_cur(text, &linep, &charp);
	if (!*linep) return;
	old= *charp;
		
	*charp= (*linep)->len;

	if(!sel) txt_pop_sel(text);
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, *linep), old, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
}

void txt_move_bof (Text *text, short sel)
{
	TextLine **linep;
	int *charp, old;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else txt_curs_cur(text, &linep, &charp);
	if (!*linep) return;
	old= *charp;

	*linep= text->lines.first;
	*charp= 0;

	if(!sel) txt_pop_sel(text);
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, *linep), old, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
}

void txt_move_eof (Text *text, short sel)
{
	TextLine **linep;
	int *charp, old;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else txt_curs_cur(text, &linep, &charp);
	if (!*linep) return;
	old= *charp;

	*linep= text->lines.last;
	*charp= (*linep)->len;

	if(!sel) txt_pop_sel(text);
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, *linep), old, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);	
}

void txt_move_toline (Text *text, unsigned int line, short sel)
{
	txt_move_to(text, line, 0, sel);
}

void txt_move_to (Text *text, unsigned int line, unsigned int ch, short sel)
{
	TextLine **linep, *oldl;
	int *charp, oldc;
	unsigned int i;
	
	if (!text) return;
	if(sel) txt_curs_sel(text, &linep, &charp);
	else txt_curs_cur(text, &linep, &charp);
	if (!*linep) return;
	oldc= *charp;
	oldl= *linep;
	
	*linep= text->lines.first;
	for (i=0; i<line; i++) {
		if ((*linep)->next) *linep= (*linep)->next;
		else break;
	}
	if (ch>(unsigned int)((*linep)->len))
		ch= (unsigned int)((*linep)->len);
	*charp= ch;
	
	if(!sel) txt_pop_sel(text);
	if(!undoing) txt_undo_add_toop(text, sel?UNDO_STO:UNDO_CTO, txt_get_span(text->lines.first, oldl), oldc, txt_get_span(text->lines.first, *linep), (unsigned short)*charp);
}

/****************************/
/* Text selection functions */
/****************************/

static void txt_curs_swap (Text *text)
{
	TextLine *tmpl;
	int tmpc;
		
	tmpl= text->curl;
	text->curl= text->sell;
	text->sell= tmpl;
	
	tmpc= text->curc;
	text->curc= text->selc;
	text->selc= tmpc;
	
	if(!undoing) txt_undo_add_op(text, UNDO_SWAP);
}

static void txt_pop_first (Text *text)
{
			
	if (txt_get_span(text->curl, text->sell)<0 ||
		(text->curl==text->sell && text->curc>text->selc)) {	
		txt_curs_swap(text);
	}

	if(!undoing) txt_undo_add_toop(text, UNDO_STO,
		txt_get_span(text->lines.first, text->sell), 
		text->selc, 
		txt_get_span(text->lines.first, text->curl), 
		text->curc);		
	
	txt_pop_sel(text);
}

static void txt_pop_last (Text *text)
{
	if (txt_get_span(text->curl, text->sell)>0 ||
		(text->curl==text->sell && text->curc<text->selc)) {
		txt_curs_swap(text);
	}

	if(!undoing) txt_undo_add_toop(text, UNDO_STO,
		txt_get_span(text->lines.first, text->sell), 
		text->selc, 
		txt_get_span(text->lines.first, text->curl), 
		text->curc);		
	
	txt_pop_sel(text);
}

/* never used: CVS 1.19 */
/*  static void txt_pop_selr (Text *text) */

void txt_pop_sel (Text *text)
{
	text->sell= text->curl;
	text->selc= text->curc;	
}

void txt_order_cursors(Text *text)
{
	if (!text) return;
	if (!text->curl) return;
	if (!text->sell) return;
	
		/* Flip so text->curl is before text->sell */
	if (txt_get_span(text->curl, text->sell)<0 ||
			(text->curl==text->sell && text->curc>text->selc))
		txt_curs_swap(text);
}

int txt_has_sel(Text *text)
{
	return ((text->curl!=text->sell) || (text->curc!=text->selc));
}

static void txt_delete_sel (Text *text)
{
	TextLine *tmpl;
	TextMarker *mrk;
	char *buf;
	int move, lineno;
	
	if (!text) return;
	if (!text->curl) return;
	if (!text->sell) return;

	if (!txt_has_sel(text)) return;
	
	txt_order_cursors(text);

	if(!undoing) {
		buf= txt_sel_to_buf(text);
		txt_undo_add_block(text, UNDO_DBLOCK, buf);
		MEM_freeN(buf);
	}

	buf= MEM_mallocN(text->curc+(text->sell->len - text->selc)+1, "textline_string");
	
	if (text->curl != text->sell) {
		txt_clear_marker_region(text, text->curl, text->curc, text->curl->len, 0, 0);
		move= txt_get_span(text->curl, text->sell);
	} else {
		mrk= txt_find_marker_region(text, text->curl, text->curc, text->selc, 0, 0);
		if (mrk && (mrk->start > text->curc || mrk->end < text->selc))
			txt_clear_marker_region(text, text->curl, text->curc, text->selc, 0, 0);
		move= 0;
	}

	mrk= txt_find_marker_region(text, text->sell, text->selc-1, text->sell->len, 0, 0);
	if (mrk) {
		lineno= mrk->lineno;
		do {
			mrk->lineno -= move;
			if (mrk->start > text->curc) mrk->start -= text->selc - text->curc;
			mrk->end -= text->selc - text->curc;
			mrk= mrk->next;
		} while (mrk && mrk->lineno==lineno);
	}

	strncpy(buf, text->curl->line, text->curc);
	strcpy(buf+text->curc, text->sell->line + text->selc);
	buf[text->curc+(text->sell->len - text->selc)]=0;

	make_new_line(text->curl, buf);
	
	tmpl= text->sell;
	while (tmpl != text->curl) {
		tmpl= tmpl->prev;
		if (!tmpl) break;
		
		txt_delete_line(text, tmpl->next);
	}
	
	text->sell= text->curl;
	text->selc= text->curc;
}

void txt_sel_all (Text *text)
{
	if (!text) return;

	text->curl= text->lines.first;
	text->curc= 0;
	
	text->sell= text->lines.last;
	text->selc= text->sell->len;
}

void txt_sel_line (Text *text)
{
	if (!text) return;
	if (!text->curl) return;
	
	text->curc= 0;
	text->sell= text->curl;
	text->selc= text->sell->len;
}

/***************************/
/* Cut and paste functions */
/***************************/

char *txt_to_buf (Text *text)
{
	int length;
	TextLine *tmp, *linef, *linel;
	int charf, charl;
	char *buf;
	
	if (!text) return NULL;
	if (!text->curl) return NULL;
	if (!text->sell) return NULL;
	if (!text->lines.first) return NULL;

	linef= text->lines.first;
	charf= 0;
		
	linel= text->lines.last;
	charl= linel->len;

	if (linef == text->lines.last) {
		length= charl-charf;

		buf= MEM_mallocN(length+2, "text buffer");
		
		BLI_strncpy(buf, linef->line + charf, length+1);
		buf[length]=0;
	} else {
		length= linef->len - charf;
		length+= charl;
		length+= 2; /* For the 2 '\n' */
		
		tmp= linef->next;
		while (tmp && tmp!= linel) {
			length+= tmp->len+1;
			tmp= tmp->next;
		}
		
		buf= MEM_mallocN(length+1, "cut buffer");

		strncpy(buf, linef->line + charf, linef->len-charf);
		length= linef->len - charf;
		
		buf[length++]='\n';
		
		tmp= linef->next;
		while (tmp && tmp!=linel) {
			strncpy(buf+length, tmp->line, tmp->len);
			length+= tmp->len;
			
			buf[length++]='\n';			
			
			tmp= tmp->next;
		}
		strncpy(buf+length, linel->line, charl);
		length+= charl;
		
		/* python compiler wants an empty end line */
		buf[length++]='\n';			
		buf[length]=0;
	}
	
	return buf;
}

int txt_find_string(Text *text, char *findstr, int wrap)
{
	TextLine *tl, *startl;
	char *s= NULL;
	int oldcl, oldsl;

	if (!text || !text->curl || !text->sell) return 0;
	
	txt_order_cursors(text);

	oldcl= txt_get_span(text->lines.first, text->curl);
	oldsl= txt_get_span(text->lines.first, text->sell);
	tl= startl= text->sell;
	
	s= strstr(&tl->line[text->selc], findstr);
	while (!s) {
		tl= tl->next;
		if (!tl) {
			if (wrap)
				tl= text->lines.first;
			else
				break;
		}

		s= strstr(tl->line, findstr);
		if (tl==startl)
			break;
	}
	
	if (s) {
		int newl= txt_get_span(text->lines.first, tl);
		int newc= (int)(s-tl->line);
		txt_move_to(text, newl, newc, 0);
		txt_move_to(text, newl, newc + strlen(findstr), 1);
		return 1;				
	} else
		return 0;
}

char *txt_sel_to_buf (Text *text)
{
	char *buf;
	int length=0;
	TextLine *tmp, *linef, *linel;
	int charf, charl;
	
	if (!text) return NULL;
	if (!text->curl) return NULL;
	if (!text->sell) return NULL;
	
	if (text->curl==text->sell) {
		linef= linel= text->curl;
		
		if (text->curc < text->selc) {
			charf= text->curc;
			charl= text->selc;
		} else{
			charf= text->selc;
			charl= text->curc;
		}
	} else if (txt_get_span(text->curl, text->sell)<0) {
		linef= text->sell;
		linel= text->curl;

		charf= text->selc;		
		charl= text->curc;
	} else {
		linef= text->curl;
		linel= text->sell;
		
		charf= text->curc;
		charl= text->selc;
	}

	if (linef == linel) {
		length= charl-charf;

		buf= MEM_mallocN(length+1, "sel buffer");
		
		BLI_strncpy(buf, linef->line + charf, length+1);
	} else {
		length+= linef->len - charf;
		length+= charl;
		length++; /* For the '\n' */
		
		tmp= linef->next;
		while (tmp && tmp!= linel) {
			length+= tmp->len+1;
			tmp= tmp->next;
		}
		
		buf= MEM_mallocN(length+1, "sel buffer");
		
		strncpy(buf, linef->line+ charf, linef->len-charf);
		length= linef->len-charf;
		
		buf[length++]='\n';
		
		tmp= linef->next;
		while (tmp && tmp!=linel) {
			strncpy(buf+length, tmp->line, tmp->len);
			length+= tmp->len;
			
			buf[length++]='\n';			
			
			tmp= tmp->next;
		}
		strncpy(buf+length, linel->line, charl);
		length+= charl;
		
		buf[length]=0;
	}	

	return buf;
}

static void txt_shift_markers(Text *text, int lineno, int count)
{
	TextMarker *marker;

	for (marker=text->markers.first; marker; marker= marker->next)
		if (marker->lineno>=lineno) {
			marker->lineno+= count;
		}
}

void txt_insert_buf(Text *text, const char *in_buffer)
{
	int i=0, l=0, j, u, len, lineno= -1, count= 0;
	TextLine *add;

	if (!text) return;
	if (!in_buffer) return;

	txt_delete_sel(text);
	
	if(!undoing) txt_undo_add_block (text, UNDO_IBLOCK, in_buffer); 	

	u= undoing;
	undoing= 1;

	/* Read the first line (or as close as possible */
	while (in_buffer[i] && in_buffer[i]!='\n') {
		txt_add_raw_char(text, in_buffer[i]);
		i++;
	}
	
	if (in_buffer[i]=='\n') txt_split_curline(text);
	else { undoing = u; return; }
	i++;

	/* Read as many full lines as we can */
	len= strlen(in_buffer);
	lineno= txt_get_span(text->lines.first, text->curl);

	while (i<len) {
		l=0;

		while (in_buffer[i] && in_buffer[i]!='\n') {
			i++; l++;
		}
	
		if(in_buffer[i]=='\n') {
			add= txt_new_linen(in_buffer +(i-l), l);
			BLI_insertlinkbefore(&text->lines, text->curl, add);
			i++;
			count++;
		} else {
			if(count) {
				txt_shift_markers(text, lineno, count);
				count= 0;
			}

			for (j= i-l; j<i && j<(int)strlen(in_buffer); j++) {
				txt_add_raw_char(text, in_buffer[j]);
			}
			break;
		}
	}

	if(count) {
		txt_shift_markers(text, lineno, count);
		count= 0;
	}

	undoing= u;
}

/******************/
/* Undo functions */
/******************/

static int max_undo_test(Text *text, int x)
{
	while (text->undo_pos+x >= text->undo_len) {
		if(text->undo_len*2 > TXT_MAX_UNDO) {
			/* XXX error("Undo limit reached, buffer cleared\n"); */
			MEM_freeN(text->undo_buf);
			init_undo_text(text);
			return 0;
		} else {
			void *tmp= text->undo_buf;
			text->undo_buf= MEM_callocN(text->undo_len*2, "undo buf");
			memcpy(text->undo_buf, tmp, text->undo_len);
			text->undo_len*=2;
			MEM_freeN(tmp);
		}
	}

	return 1;
}

static void dump_buffer(Text *text) 
{
	int i= 0;
	
	while (i++<text->undo_pos) printf("%d: %d %c\n", i, text->undo_buf[i], text->undo_buf[i]);
}

void txt_print_undo(Text *text)
{
	int i= 0;
	int op;
	const char *ops;
	int linep, charp;
	
	dump_buffer(text);
	
	printf ("---< Undo Buffer >---\n");
	
	printf ("UndoPosition is %d\n", text->undo_pos);
	
	while (i<=text->undo_pos) {
		op= text->undo_buf[i];
		
		if (op==UNDO_CLEFT) {
			ops= "Cursor left";
		} else if (op==UNDO_CRIGHT) {
			ops= "Cursor right";
		} else if (op==UNDO_CUP) {
			ops= "Cursor up";
		} else if (op==UNDO_CDOWN) {
			ops= "Cursor down";
		} else if (op==UNDO_SLEFT) {
			ops= "Selection left";
		} else if (op==UNDO_SRIGHT) {
			ops= "Selection right";
		} else if (op==UNDO_SUP) {
			ops= "Selection up";
		} else if (op==UNDO_SDOWN) {
			ops= "Selection down";
		} else if (op==UNDO_STO) {
			ops= "Selection ";
		} else if (op==UNDO_CTO) {
			ops= "Cursor ";
		} else if (op==UNDO_INSERT) {
			ops= "Insert";
		} else if (op==UNDO_BS) {
			ops= "Backspace";
		} else if (op==UNDO_DEL) {
			ops= "Delete";
		} else if (op==UNDO_SWAP) {
			ops= "Cursor swap";
		} else if (op==UNDO_DBLOCK) {
			ops= "Delete text block";
		} else if (op==UNDO_IBLOCK) {
			ops= "Insert text block";
		} else if (op==UNDO_INDENT) {
			ops= "Indent ";
		} else if (op==UNDO_UNINDENT) {
			ops= "Unindent ";
		} else if (op==UNDO_COMMENT) {
			ops= "Comment ";
		} else if (op==UNDO_UNCOMMENT) {
			ops= "Uncomment ";
		} else {
			ops= "Unknown";
		}
		
		printf ("Op (%o) at %d = %s", op, i, ops);
		if (op==UNDO_INSERT || op==UNDO_BS || op==UNDO_DEL) {
			i++;
			printf (" - Char is %c", text->undo_buf[i]);  
			i++;
		} else if (op==UNDO_STO || op==UNDO_CTO) {
			i++;

			charp= text->undo_buf[i]; i++;
			charp= charp+(text->undo_buf[i]<<8); i++;

			linep= text->undo_buf[i]; i++;
			linep= linep+(text->undo_buf[i]<<8); i++;
			linep= linep+(text->undo_buf[i]<<16); i++;
			linep= linep+(text->undo_buf[i]<<24); i++;
			
			printf ("to <%d, %d> ", linep, charp);

			charp= text->undo_buf[i]; i++;
			charp= charp+(text->undo_buf[i]<<8); i++;

			linep= text->undo_buf[i]; i++;
			linep= linep+(text->undo_buf[i]<<8); i++;
			linep= linep+(text->undo_buf[i]<<16); i++;
			linep= linep+(text->undo_buf[i]<<24); i++;
			
			printf ("from <%d, %d>", linep, charp);
		} else if (op==UNDO_DBLOCK || op==UNDO_IBLOCK) {
			i++;

			linep= text->undo_buf[i]; i++;
			linep= linep+(text->undo_buf[i]<<8); i++;
			linep= linep+(text->undo_buf[i]<<16); i++;
			linep= linep+(text->undo_buf[i]<<24); i++;
			
			printf (" (length %d) <", linep);
			
			while (linep>0) {
				putchar(text->undo_buf[i]);
				linep--; i++;
			}
			
			linep= text->undo_buf[i]; i++;
			linep= linep+(text->undo_buf[i]<<8); i++;
			linep= linep+(text->undo_buf[i]<<16); i++;
			linep= linep+(text->undo_buf[i]<<24); i++;
			printf ("> (%d)", linep);
		} else if (op==UNDO_INDENT || op==UNDO_UNINDENT) {
			i++;

			charp= text->undo_buf[i]; i++;
			charp= charp+(text->undo_buf[i]<<8); i++;

			linep= text->undo_buf[i]; i++;
			linep= linep+(text->undo_buf[i]<<8); i++;
			linep= linep+(text->undo_buf[i]<<16); i++;
			linep= linep+(text->undo_buf[i]<<24); i++;
			
			printf ("to <%d, %d> ", linep, charp);

			charp= text->undo_buf[i]; i++;
			charp= charp+(text->undo_buf[i]<<8); i++;

			linep= text->undo_buf[i]; i++;
			linep= linep+(text->undo_buf[i]<<8); i++;
			linep= linep+(text->undo_buf[i]<<16); i++;
			linep= linep+(text->undo_buf[i]<<24); i++;
			
			printf ("from <%d, %d>", linep, charp);
		}
		
		printf (" %d\n",  i);
		i++;
	}
}

static void txt_undo_add_op(Text *text, int op)
{
	if(!max_undo_test(text, 2))
		return;
	
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;
	text->undo_buf[text->undo_pos+1]= 0;
}

static void txt_undo_add_block(Text *text, int op, const char *buf)
{
	int length;
	
	length= strlen(buf);
	
	if(!max_undo_test(text, length+11))
		return;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;
	
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length>>8)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length>>16)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length>>24)&0xff;

	text->undo_pos++;
	strncpy(text->undo_buf+text->undo_pos, buf, length);
	text->undo_pos+=length;

	text->undo_buf[text->undo_pos]= (length)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length>>8)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length>>16)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (length>>24)&0xff;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;
	
	text->undo_buf[text->undo_pos+1]= 0;
}

void txt_undo_add_toop(Text *text, int op, unsigned int froml, unsigned short fromc, unsigned int tol, unsigned short toc)
{
	if(!max_undo_test(text, 15))
		return;

	if (froml==tol && fromc==toc) return;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (fromc)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (fromc>>8)&0xff;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (froml)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (froml>>8)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (froml>>16)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (froml>>24)&0xff;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (toc)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (toc>>8)&0xff;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (tol)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (tol>>8)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (tol>>16)&0xff;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= (tol>>24)&0xff;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;

	text->undo_buf[text->undo_pos+1]= 0;
}

static void txt_undo_add_charop(Text *text, int op, char c)
{
	if(!max_undo_test(text, 4))
		return;

	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= c;
	text->undo_pos++;
	text->undo_buf[text->undo_pos]= op;
	text->undo_buf[text->undo_pos+1]= 0;
}

void txt_do_undo(Text *text)
{
	int op= text->undo_buf[text->undo_pos];
	unsigned int linep, i;
	unsigned short charp;
	TextLine *holdl;
	int holdc, holdln;
	char *buf;
	
	if (text->undo_pos<0) {
		return;
	}

	text->undo_pos--;

	undoing= 1;
	
	switch(op) {
		case UNDO_CLEFT:
			txt_move_right(text, 0);
			break;
			
		case UNDO_CRIGHT:
			txt_move_left(text, 0);
			break;
			
		case UNDO_CUP:
			txt_move_down(text, 0);
			break;
			
		case UNDO_CDOWN:
			txt_move_up(text, 0);
			break;

		case UNDO_SLEFT:
			txt_move_right(text, 1);
			break;

		case UNDO_SRIGHT:
			txt_move_left(text, 1);
			break;

		case UNDO_SUP:
			txt_move_down(text, 1);
			break;

		case UNDO_SDOWN:
			txt_move_up(text, 1);
			break;
		
		case UNDO_CTO:
		case UNDO_STO:
			text->undo_pos--;
			text->undo_pos--;
			text->undo_pos--;
			text->undo_pos--;
		
			text->undo_pos--;
			text->undo_pos--;
		
			linep= text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;

			charp= text->undo_buf[text->undo_pos]; text->undo_pos--;
			charp= (charp<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			
			if (op==UNDO_CTO) {
				txt_move_toline(text, linep, 0);
				text->curc= charp;
				txt_pop_sel(text);
			} else {
				txt_move_toline(text, linep, 1);
				text->selc= charp;
			}
			
			text->undo_pos--;
			break;
			
		case UNDO_INSERT:
			txt_backspace_char(text);
			text->undo_pos--;
			text->undo_pos--;
			break;

		case UNDO_BS:
			txt_add_char(text, text->undo_buf[text->undo_pos]);
			text->undo_pos--;
			text->undo_pos--;
			break;

		case UNDO_DEL:
			txt_add_char(text, text->undo_buf[text->undo_pos]);
			txt_move_left(text, 0);
			text->undo_pos--;
			text->undo_pos--;
			break;

		case UNDO_SWAP:
			txt_curs_swap(text);
			break;

		case UNDO_DBLOCK:
			linep= text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;

			buf= MEM_mallocN(linep+1, "dblock buffer");
			for (i=0; i < linep; i++){
				buf[(linep-1)-i]= text->undo_buf[text->undo_pos]; 
				text->undo_pos--;
			}
			buf[i]= 0;
			
			txt_curs_first(text, &holdl, &holdc);
			holdln= txt_get_span(text->lines.first, holdl);
			
			txt_insert_buf(text, buf);			
			MEM_freeN(buf);

			text->curl= text->lines.first;
			while (holdln>0) {
				if(text->curl->next)
					text->curl= text->curl->next;
					
				holdln--;
			}
			text->curc= holdc;

			linep= text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;

			text->undo_pos--;
			
			break;

		case UNDO_IBLOCK:
			linep= text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep= (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;

			txt_delete_sel(text);
			while (linep>0) {
				txt_backspace_char(text);
				text->undo_pos--;
				linep--;
			}

			text->undo_pos--;
			text->undo_pos--;
			text->undo_pos--; 
			text->undo_pos--;
			
			text->undo_pos--;

			break;
		case UNDO_INDENT:
		case UNDO_UNINDENT:
		case UNDO_COMMENT:
		case UNDO_UNCOMMENT:
			linep= text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep = (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep = (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep = (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			//linep is now the end line of the selection
			
			charp = text->undo_buf[text->undo_pos]; text->undo_pos--;
			charp = (charp<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			//charp is the last char selected or text->line->len
			//set the selcetion for this now
			text->selc = charp;
			text->sell = text->lines.first;
			for (i= 0; i < linep; i++) {
				text->sell = text->sell->next;
			}

			linep= text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep = (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep = (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			linep = (linep<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			//first line to be selected
			
			charp = text->undo_buf[text->undo_pos]; text->undo_pos--;
			charp = (charp<<8)+text->undo_buf[text->undo_pos]; text->undo_pos--;
			//first postion to be selected
			text->curc = charp;
			text->curl = text->lines.first;
			for (i = 0; i < linep; i++) {
				text->curl = text->curl->next;
			}

			
			if (op==UNDO_INDENT) {
				unindent(text);
			} else if (op== UNDO_UNINDENT) {
				indent(text);
			} else if (op == UNDO_COMMENT) {
				uncomment(text);
			} else if (op == UNDO_UNCOMMENT) {
				comment(text);
			}

			text->undo_pos--;
			break;
		default:
			//XXX error("Undo buffer error - resetting");
			text->undo_pos= -1;
			
			break;
	}

	/* next undo step may need evaluating */
	if (text->undo_pos>=0) {
		switch (text->undo_buf[text->undo_pos]) {
			case UNDO_STO:
				txt_do_undo(text);
				txt_do_redo(text); /* selections need restoring */
				break;
			case UNDO_SWAP:
				txt_do_undo(text); /* swaps should appear transparent */
				break;
		}
	}
	
	undoing= 0;	
}

void txt_do_redo(Text *text)
{
	char op;
	unsigned int linep, i;
	unsigned short charp;
	char *buf;
	
	text->undo_pos++;	
	op= text->undo_buf[text->undo_pos];
	
	if (!op) {
		text->undo_pos--;
		return;
	}
	
	undoing= 1;

	switch(op) {
		case UNDO_CLEFT:
			txt_move_left(text, 0);
			break;
			
		case UNDO_CRIGHT:
			txt_move_right(text, 0);
			break;
			
		case UNDO_CUP:
			txt_move_up(text, 0);
			break;
			
		case UNDO_CDOWN:
			txt_move_down(text, 0);
			break;

		case UNDO_SLEFT:
			txt_move_left(text, 1);
			break;

		case UNDO_SRIGHT:
			txt_move_right(text, 1);
			break;

		case UNDO_SUP:
			txt_move_up(text, 1);
			break;

		case UNDO_SDOWN:
			txt_move_down(text, 1);
			break;
		
		case UNDO_INSERT:
			text->undo_pos++;
			txt_add_char(text, text->undo_buf[text->undo_pos]);
			text->undo_pos++;
			break;

		case UNDO_BS:
			text->undo_pos++;
			txt_backspace_char(text);
			text->undo_pos++;
			break;

		case UNDO_DEL:
			text->undo_pos++;
			txt_delete_char(text);
			text->undo_pos++;
			break;

		case UNDO_SWAP:
			txt_curs_swap(text);
			txt_do_redo(text); /* swaps should appear transparent a*/
			break;
			
		case UNDO_CTO:
		case UNDO_STO:
			text->undo_pos++;
			text->undo_pos++;

			text->undo_pos++;
			text->undo_pos++;
			text->undo_pos++;
			text->undo_pos++;

			text->undo_pos++;

			charp= text->undo_buf[text->undo_pos];
			text->undo_pos++;
			charp= charp+(text->undo_buf[text->undo_pos]<<8);

			text->undo_pos++;
			linep= text->undo_buf[text->undo_pos]; text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<16); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<24); text->undo_pos++;
			
			if (op==UNDO_CTO) {
				txt_move_toline(text, linep, 0);
				text->curc= charp;
				txt_pop_sel(text);
			} else {
				txt_move_toline(text, linep, 1);
				text->selc= charp;
			}

			break;

		case UNDO_DBLOCK:
			text->undo_pos++;
			linep= text->undo_buf[text->undo_pos]; text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<16); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<24); text->undo_pos++;

			txt_delete_sel(text);
			text->undo_pos+=linep;

			text->undo_pos++;
			text->undo_pos++;
			text->undo_pos++; 
			text->undo_pos++;
			
			break;

		case UNDO_IBLOCK:
			text->undo_pos++;
			linep= text->undo_buf[text->undo_pos]; text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<16); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<24); text->undo_pos++;

			buf= MEM_mallocN(linep+1, "iblock buffer");
			memcpy (buf, &text->undo_buf[text->undo_pos], linep);
			text->undo_pos+= linep;
			buf[linep]= 0;
			
			txt_insert_buf(text, buf);			
			MEM_freeN(buf);

			linep= text->undo_buf[text->undo_pos]; text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<16); text->undo_pos++;
			linep= linep+(text->undo_buf[text->undo_pos]<<24); text->undo_pos++;
			(void)linep;

			break;
		case UNDO_INDENT:
		case UNDO_UNINDENT:
		case UNDO_COMMENT:
		case UNDO_UNCOMMENT:
			text->undo_pos++;
			charp = text->undo_buf[text->undo_pos]; text->undo_pos++;
			charp = charp+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			//charp is the first char selected or 0
			
			linep= text->undo_buf[text->undo_pos]; text->undo_pos++;
			linep = linep+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			linep = linep+(text->undo_buf[text->undo_pos]<<16); text->undo_pos++;
			linep = linep+(text->undo_buf[text->undo_pos]<<24); text->undo_pos++;
			//linep is now the first line of the selection			
			//set the selcetion for this now
			text->curc = charp;
			text->curl = text->lines.first;
			for (i= 0; i < linep; i++) {
				text->curl = text->curl->next;
			}
			
			charp = text->undo_buf[text->undo_pos]; text->undo_pos++;
			charp = charp+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			//last postion to be selected
			linep= text->undo_buf[text->undo_pos]; text->undo_pos++;
			linep = linep+(text->undo_buf[text->undo_pos]<<8); text->undo_pos++;
			linep = linep+(text->undo_buf[text->undo_pos]<<16); text->undo_pos++;
			linep = linep+(text->undo_buf[text->undo_pos]<<24); text->undo_pos++;
			//Last line to be selected
			
			text->selc = charp;
			text->sell = text->lines.first;
			for (i = 0; i < linep; i++) {
				text->sell = text->sell->next;
			}

			if (op==UNDO_INDENT) {
				indent(text);
			} else if (op== UNDO_UNINDENT) {
				unindent(text);
			} else if (op == UNDO_COMMENT) {
				comment(text);
			} else if (op == UNDO_UNCOMMENT) {
				uncomment(text);
			}
			break;
		default:
			//XXX error("Undo buffer error - resetting");
			text->undo_pos= -1;

			break;
	}
	
	undoing= 0;	
}

/**************************/
/* Line editing functions */ 
/**************************/

void txt_split_curline (Text *text) 
{
	TextLine *ins;
	TextMarker *mrk;
	char *left, *right;
	int lineno= -1;
	
	if (!text) return;
	if (!text->curl) return;

	txt_delete_sel(text);

	/* Move markers */

	lineno= txt_get_span(text->lines.first, text->curl);
	mrk= text->markers.first;
	while (mrk) {
		if (mrk->lineno==lineno && mrk->start>text->curc) {
			mrk->lineno++;
			mrk->start -= text->curc;
			mrk->end -= text->curc;
		} else if (mrk->lineno > lineno) {
			mrk->lineno++;
		}
		mrk= mrk->next;
	}

	/* Make the two half strings */

	left= MEM_mallocN(text->curc+1, "textline_string");
	if (text->curc) memcpy(left, text->curl->line, text->curc);
	left[text->curc]=0;
	
	right= MEM_mallocN(text->curl->len - text->curc+1, "textline_string");
	if (text->curl->len - text->curc) memcpy(right, text->curl->line+text->curc, text->curl->len-text->curc);
	right[text->curl->len - text->curc]=0;

	MEM_freeN(text->curl->line);
	if (text->curl->format) MEM_freeN(text->curl->format);

	/* Make the new TextLine */
	
	ins= MEM_mallocN(sizeof(TextLine), "textline");
	ins->line= left;
	ins->format= NULL;
	ins->len= text->curc;
	
	text->curl->line= right;
	text->curl->format= NULL;
	text->curl->len= text->curl->len - text->curc;
	
	BLI_insertlinkbefore(&text->lines, text->curl, ins);	
	
	text->curc=0;
	
	txt_make_dirty(text);
	txt_clean_text(text);
	
	txt_pop_sel(text);
	if(!undoing) txt_undo_add_charop(text, UNDO_INSERT, '\n');
}

static void txt_delete_line (Text *text, TextLine *line) 
{
	TextMarker *mrk=NULL, *nxt;
	int lineno= -1;

	if (!text) return;
	if (!text->curl) return;

	lineno= txt_get_span(text->lines.first, line);
	mrk= text->markers.first;
	while (mrk) {
		nxt= mrk->next;
		if (mrk->lineno==lineno)
			BLI_freelinkN(&text->markers, mrk);
		else if (mrk->lineno > lineno)
			mrk->lineno--;
		mrk= nxt;
	}

	BLI_remlink (&text->lines, line);
	
	if (line->line) MEM_freeN(line->line);
	if (line->format) MEM_freeN(line->format);

	MEM_freeN(line);

	txt_make_dirty(text);
	txt_clean_text(text);
}

static void txt_combine_lines (Text *text, TextLine *linea, TextLine *lineb)
{
	char *tmp;
	TextMarker *mrk= NULL;
	int lineno=-1;
	
	if (!text) return;
	
	if(!linea || !lineb) return;

	mrk= txt_find_marker_region(text, lineb, 0, lineb->len, 0, 0);
	if (mrk) {
		lineno= mrk->lineno;
		do {
			mrk->lineno--;
			mrk->start += linea->len;
			mrk->end += linea->len;
			mrk= mrk->next;
		} while (mrk && mrk->lineno==lineno);
	}
	if (lineno==-1) lineno= txt_get_span(text->lines.first, lineb);
	
	tmp= MEM_mallocN(linea->len+lineb->len+1, "textline_string");
	
	strcpy(tmp, linea->line);
	strcat(tmp, lineb->line);

	make_new_line(linea, tmp);
	
	txt_delete_line(text, lineb);
	
	txt_make_dirty(text);
	txt_clean_text(text);
}

void txt_delete_char (Text *text) 
{
	char c='\n';
	
	if (!text) return;
	if (!text->curl) return;

	if (txt_has_sel(text)) { /* deleting a selection */
		txt_delete_sel(text);
		txt_make_dirty(text);
		return;
	}
	else if (text->curc== text->curl->len) { /* Appending two lines */
		if (text->curl->next) {
			txt_combine_lines(text, text->curl, text->curl->next);
			txt_pop_sel(text);
		}
	} else { /* Just deleting a char */
		int i= text->curc;

		TextMarker *mrk= txt_find_marker_region(text, text->curl, i-1, text->curl->len, 0, 0);
		if (mrk) {
			int lineno= mrk->lineno;
			if (mrk->end==i) {
				if ((mrk->flags & TMARK_TEMP) && !(mrk->flags & TMARK_EDITALL)) {
					txt_clear_markers(text, mrk->group, TMARK_TEMP);
				} else {
					BLI_freelinkN(&text->markers, mrk);
				}
				return;
			}
			do {
				if (mrk->start>i) mrk->start--;
				mrk->end--;
				mrk= mrk->next;
			} while (mrk && mrk->lineno==lineno);
		}
		
		c= text->curl->line[i];
		while(i< text->curl->len) {
			text->curl->line[i]= text->curl->line[i+1];
			i++;
		}
		text->curl->len--;

		txt_pop_sel(text);
	}

	txt_make_dirty(text);
	txt_clean_text(text);
	
	if(!undoing) txt_undo_add_charop(text, UNDO_DEL, c);
}

void txt_delete_word (Text *text) 
{
	txt_jump_right(text, 1);
	txt_delete_sel(text);
}

void txt_backspace_char (Text *text) 
{
	char c='\n';
	
	if (!text) return;
	if (!text->curl) return;
	
	if (txt_has_sel(text)) { /* deleting a selection */
		txt_delete_sel(text);
		txt_make_dirty(text);
		return;
	}
	else if (text->curc==0) { /* Appending two lines */
		if (!text->curl->prev) return;
		
		text->curl= text->curl->prev;
		text->curc= text->curl->len;
		
		txt_combine_lines(text, text->curl, text->curl->next);
		txt_pop_sel(text);
	}
	else { /* Just backspacing a char */
		int i= text->curc-1;

		TextMarker *mrk= txt_find_marker_region(text, text->curl, i, text->curl->len, 0, 0);
		if (mrk) {
			int lineno= mrk->lineno;
			if (mrk->start==i+1) {
				if ((mrk->flags & TMARK_TEMP) && !(mrk->flags & TMARK_EDITALL)) {
					txt_clear_markers(text, mrk->group, TMARK_TEMP);
				} else {
					BLI_freelinkN(&text->markers, mrk);
				}
				return;
			}
			do {
				if (mrk->start>i) mrk->start--;
				mrk->end--;
				mrk= mrk->next;
			} while (mrk && mrk->lineno==lineno);
		}
		
		c= text->curl->line[i];
		while(i< text->curl->len) {
			text->curl->line[i]= text->curl->line[i+1];
			i++;
		}
		text->curl->len--;
		text->curc--;

		txt_pop_sel(text);
	}

	txt_make_dirty(text);
	txt_clean_text(text);
	
	if(!undoing) txt_undo_add_charop(text, UNDO_BS, c);
}

void txt_backspace_word (Text *text) 
{
	txt_jump_left(text, 1);
	txt_delete_sel(text);
}

/* Max spaces to replace a tab with, currently hardcoded to TXT_TABSIZE = 4.
 * Used by txt_convert_tab_to_spaces, indent and unintent.
 * Remember to change this string according to max tab size */
static char tab_to_spaces[] = "    ";

static void txt_convert_tab_to_spaces (Text *text)
{
	/* sb aims to pad adjust the tab-width needed so that the right number of spaces
	 * is added so that the indention of the line is the right width (i.e. aligned
	 * to multiples of TXT_TABSIZE)
	 */
	char *sb = &tab_to_spaces[text->curc % TXT_TABSIZE];
	txt_insert_buf(text, sb);
}

static int txt_add_char_intern (Text *text, char add, int replace_tabs)
{
	int len, lineno;
	char *tmp;
	TextMarker *mrk;
	
	if (!text) return 0;
	if (!text->curl) return 0;

	if (add=='\n') {
		txt_split_curline(text);
		return 1;
	}
	
	/* insert spaces rather then tabs */
	if (add == '\t' && replace_tabs) {
		txt_convert_tab_to_spaces(text);
		return 1;
	}

	txt_delete_sel(text);
	
	mrk= txt_find_marker_region(text, text->curl, text->curc-1, text->curl->len, 0, 0);
	if (mrk) {
		lineno= mrk->lineno;
		do {
			if (mrk->start>text->curc) mrk->start++;
			mrk->end++;
			mrk= mrk->next;
		} while (mrk && mrk->lineno==lineno);
	}
	
	tmp= MEM_mallocN(text->curl->len+2, "textline_string");
	
	if(text->curc) memcpy(tmp, text->curl->line, text->curc);
	tmp[text->curc]= add;
	
	len= text->curl->len - text->curc;
	if(len>0) memcpy(tmp+text->curc+1, text->curl->line+text->curc, len);
	tmp[text->curl->len+1]=0;
	make_new_line(text->curl, tmp);
		
	text->curc++;

	txt_pop_sel(text);
	
	txt_make_dirty(text);
	txt_clean_text(text);

	if(!undoing) txt_undo_add_charop(text, UNDO_INSERT, add);
	return 1;
}

int txt_add_char (Text *text, char add)
{
	return txt_add_char_intern(text, add, text->flags & TXT_TABSTOSPACES);
}

int txt_add_raw_char (Text *text, char add)
{
	return txt_add_char_intern(text, add, 0);
}

void txt_delete_selected(Text *text)
{
	txt_delete_sel(text);
	txt_make_dirty(text);
}

int txt_replace_char (Text *text, char add)
{
	char del;
	
	if (!text) return 0;
	if (!text->curl) return 0;

	/* If text is selected or we're at the end of the line just use txt_add_char */
	if (text->curc==text->curl->len || txt_has_sel(text) || add=='\n') {
		TextMarker *mrk;
		int i= txt_add_char(text, add);
		mrk= txt_find_marker(text, text->curl, text->curc, 0, 0);
		if (mrk && mrk->end==text->curc) mrk->end--;
		return i;
	}
	
	del= text->curl->line[text->curc];
	text->curl->line[text->curc]= (unsigned char) add;
	text->curc++;
	txt_pop_sel(text);
	
	txt_make_dirty(text);
	txt_clean_text(text);

	/* Should probably create a new op for this */
	if(!undoing) {
		txt_undo_add_charop(text, UNDO_DEL, del);
		txt_undo_add_charop(text, UNDO_INSERT, add);
	}
	return 1;
}

void indent(Text *text)
{
	int len, num;
	char *tmp;

	const char *add = "\t";
	int indentlen = 1;
	
	/* hardcoded: TXT_TABSIZE = 4 spaces: */
	int spaceslen = TXT_TABSIZE;

	/* insert spaces rather then tabs */
	if (text->flags & TXT_TABSTOSPACES){
		add = tab_to_spaces;
		indentlen = spaceslen;
	}
	
	if (!text) return;
	if (!text->curl) return;
	if (!text->sell) return;

	num = 0;
	while (TRUE)
	{
		tmp= MEM_mallocN(text->curl->len+indentlen+1, "textline_string");
		
		text->curc = 0; 
		if(text->curc) memcpy(tmp, text->curl->line, text->curc); /* XXX never true, check prev line */
		memcpy(tmp+text->curc, add, indentlen);
		
		len= text->curl->len - text->curc;
		if(len>0) memcpy(tmp+text->curc+indentlen, text->curl->line+text->curc, len);
		tmp[text->curl->len+indentlen]= 0;

		make_new_line(text->curl, tmp);
			
		text->curc+= indentlen;
		
		txt_make_dirty(text);
		txt_clean_text(text);
		
		if(text->curl == text->sell) 
		{
			text->selc = text->sell->len;
			break;
		} else {
			text->curl = text->curl->next;
			num++;
		}
	}
	text->curc = 0;
	while( num > 0 )
	{
		text->curl = text->curl->prev;
		num--;
	}
	
	if(!undoing) 
	{
		txt_undo_add_toop(text, UNDO_INDENT, txt_get_span(text->lines.first, text->curl), text->curc, txt_get_span(text->lines.first, text->sell), text->selc);
	}
}

void unindent(Text *text)
{
	int num = 0;
	const char *remove = "\t";
	int indent = 1;
	
	/* hardcoded: TXT_TABSIZE = 4 spaces: */
	int spaceslen = TXT_TABSIZE;

	/* insert spaces rather then tabs */
	if (text->flags & TXT_TABSTOSPACES){
		remove = tab_to_spaces;
		indent = spaceslen;
	}

	if (!text) return;
	if (!text->curl) return;
	if (!text->sell) return;

	while(TRUE)
	{
		int i = 0;
		
		if (BLI_strncasecmp(text->curl->line, remove, indent) == 0)
		{
			while(i< text->curl->len) {
				text->curl->line[i]= text->curl->line[i+indent];
				i++;
			}
			text->curl->len-= indent;
		}
	
		txt_make_dirty(text);
		txt_clean_text(text);
		
		if(text->curl == text->sell) 
		{
			text->selc = text->sell->len;
			break;
		} else {
			text->curl = text->curl->next;
			num++;
		}
		
	}
	text->curc = 0;
	while( num > 0 )
	{
		text->curl = text->curl->prev;
		num--;
	}
	
	if(!undoing) 
	{
		txt_undo_add_toop(text, UNDO_UNINDENT, txt_get_span(text->lines.first, text->curl), text->curc, txt_get_span(text->lines.first, text->sell), text->selc);
	}
}

void comment(Text *text)
{
	int len, num;
	char *tmp;
	char add = '#';
	
	if (!text) return;
	if (!text->curl) return;
	if (!text->sell) return;// Need to change this need to check if only one line is selected to more then one

	num = 0;
	while (TRUE)
	{
		tmp= MEM_mallocN(text->curl->len+2, "textline_string");
		
		text->curc = 0; 
		if(text->curc) memcpy(tmp, text->curl->line, text->curc);
		tmp[text->curc]= add;
		
		len= text->curl->len - text->curc;
		if(len>0) memcpy(tmp+text->curc+1, text->curl->line+text->curc, len);
		tmp[text->curl->len+1]=0;

		make_new_line(text->curl, tmp);
			
		text->curc++;
		
		txt_make_dirty(text);
		txt_clean_text(text);
		
		if(text->curl == text->sell) 
		{
			text->selc = text->sell->len;
			break;
		} else {
			text->curl = text->curl->next;
			num++;
		}
	}
	text->curc = 0;
	while( num > 0 )
	{
		text->curl = text->curl->prev;
		num--;
	}
	
	if(!undoing) 
	{
		txt_undo_add_toop(text, UNDO_COMMENT, txt_get_span(text->lines.first, text->curl), text->curc, txt_get_span(text->lines.first, text->sell), text->selc);
	}
}

void uncomment(Text *text)
{
	int num = 0;
	char remove = '#';
	
	if (!text) return;
	if (!text->curl) return;
	if (!text->sell) return;

	while(TRUE)
	{
		int i = 0;
		
		if (text->curl->line[i] == remove)
		{
			while(i< text->curl->len) {
				text->curl->line[i]= text->curl->line[i+1];
				i++;
			}
			text->curl->len--;
		}
			 
	
		txt_make_dirty(text);
		txt_clean_text(text);
		
		if(text->curl == text->sell) 
		{
			text->selc = text->sell->len;
			break;
		} else {
			text->curl = text->curl->next;
			num++;
		}
		
	}
	text->curc = 0;
	while( num > 0 )
	{
		text->curl = text->curl->prev;
		num--;
	}
	
	if(!undoing) 
	{
		txt_undo_add_toop(text, UNDO_UNCOMMENT, txt_get_span(text->lines.first, text->curl), text->curc, txt_get_span(text->lines.first, text->sell), text->selc);
	}
}

int setcurr_tab_spaces (Text *text, int space)
{
	int i = 0;
	int test = 0;
	const char *word = ":";
	const char *comm = "#";
	const char indent= (text->flags & TXT_TABSTOSPACES) ? ' ' : '\t';
	static const char *back_words[]= {"return", "break", "continue", "pass", "yield", NULL};
	if (!text) return 0;
	if (!text->curl) return 0;

	while (text->curl->line[i] == indent)
	{
		//we only count those tabs/spaces that are before any text or before the curs;
		if (i == text->curc)
		{
			return i;
		} else {
			i++;
		}
	}
	if(strstr(text->curl->line, word))
	{
		/* if we find a ':' on this line, then add a tab but not if it is:
		 * 	1) in a comment
		 * 	2) within an identifier
		 *	3) after the cursor (text->curc), i.e. when creating space before a function def [#25414] 
		 */
		int a, indent = 0;
		for(a=0; (a < text->curc) && (text->curl->line[a] != '\0'); a++)
		{
			char ch= text->curl->line[a];
			if (ch=='#') {
				break;
			} else if (ch==':') {
				indent = 1;
			} else if (ch==']' || ch=='}' || ch=='"' || ch=='\'') {
				indent = 0;
			}
		}
		if (indent) {
			i += space;
		}
	}

	for(test=0; back_words[test]; test++)
	{
		/* if there are these key words then remove a tab because we are done with the block */
		if(strstr(text->curl->line, back_words[test]) && i > 0)
		{
			if(strcspn(text->curl->line, back_words[test]) < strcspn(text->curl->line, comm))
			{
				i -= space;
			}
		}
	}
	return i;
}

/*********************************/
/* Text marker utility functions */
/*********************************/

/* Creates and adds a marker to the list maintaining sorted order */
void txt_add_marker(Text *text, TextLine *line, int start, int end, const unsigned char color[4], int group, int flags) {
	TextMarker *tmp, *marker;

	marker= MEM_mallocN(sizeof(TextMarker), "text_marker");
	
	marker->lineno= txt_get_span(text->lines.first, line);
	marker->start= MIN2(start, end);
	marker->end= MAX2(start, end);
	marker->group= group;
	marker->flags= flags;

	marker->color[0]= color[0];
	marker->color[1]= color[1];
	marker->color[2]= color[2];
	marker->color[3]= color[3];

	for (tmp=text->markers.last; tmp; tmp=tmp->prev)
		if (tmp->lineno < marker->lineno || (tmp->lineno==marker->lineno && tmp->start < marker->start))
			break;

	if (tmp) BLI_insertlinkafter(&text->markers, tmp, marker);
	else BLI_addhead(&text->markers, marker);
}

/* Returns the first matching marker on the specified line between two points.
   If the group or flags fields are non-zero the returned flag must be in the
   specified group and have at least the specified flags set. */
TextMarker *txt_find_marker_region(Text *text, TextLine *line, int start, int end, int group, int flags) {
	TextMarker *marker, *next;
	int lineno= txt_get_span(text->lines.first, line);
	
	for (marker=text->markers.first; marker; marker=next) {
		next= marker->next;

		if (group && marker->group != group) continue;
		else if ((marker->flags & flags) != flags) continue;
		else if (marker->lineno < lineno) continue;
		else if (marker->lineno > lineno) break;

		if ((marker->start==marker->end && start<=marker->start && marker->start<=end) ||
				(marker->start<end && marker->end>start))
			return marker;
	}
	return NULL;
}

/* Clears all markers on the specified line between two points. If the group or
   flags fields are non-zero the returned flag must be in the specified group
   and have at least the specified flags set. */
short txt_clear_marker_region(Text *text, TextLine *line, int start, int end, int group, int flags) {
	TextMarker *marker, *next;
	int lineno= txt_get_span(text->lines.first, line);
	short cleared= 0;
	
	for (marker=text->markers.first; marker; marker=next) {
		next= marker->next;

		if (group && marker->group != group) continue;
		else if ((marker->flags & flags) != flags) continue;
		else if (marker->lineno < lineno) continue;
		else if (marker->lineno > lineno) break;

		if ((marker->start==marker->end && start<=marker->start && marker->start<=end) ||
			(marker->start<end && marker->end>start)) {
			BLI_freelinkN(&text->markers, marker);
			cleared= 1;
		}
	}
	return cleared;
}

/* Clears all markers in the specified group (if given) with at least the
   specified flags set. Useful for clearing temporary markers (group=0,
   flags=TMARK_TEMP) */
short txt_clear_markers(Text *text, int group, int flags) {
	TextMarker *marker, *next;
	short cleared= 0;
	
	for (marker=text->markers.first; marker; marker=next) {
		next= marker->next;

		if ((!group || marker->group==group) &&
				(marker->flags & flags) == flags) {
			BLI_freelinkN(&text->markers, marker);
			cleared= 1;
		}
	}
	return cleared;
}

/* Finds the marker at the specified line and cursor position with at least the
   specified flags set in the given group (if non-zero). */
TextMarker *txt_find_marker(Text *text, TextLine *line, int curs, int group, int flags) {
	TextMarker *marker;
	int lineno= txt_get_span(text->lines.first, line);
	
	for (marker=text->markers.first; marker; marker=marker->next) {
		if (group && marker->group != group) continue;
		else if ((marker->flags & flags) != flags) continue;
		else if (marker->lineno < lineno) continue;
		else if (marker->lineno > lineno) break;

		if (marker->start <= curs && curs <= marker->end)
			return marker;
	}
	return NULL;
}

/* Finds the previous marker in the same group. If no other is found, the same
   marker will be returned */
TextMarker *txt_prev_marker(Text *text, TextMarker *marker) {
	TextMarker *tmp= marker;
	while (tmp) {
		if (tmp->prev) tmp= tmp->prev;
		else tmp= text->markers.last;
		if (tmp->group == marker->group)
			return tmp;
	}
	return NULL; /* Only if marker==NULL */
}

/* Finds the next marker in the same group. If no other is found, the same
   marker will be returned */
TextMarker *txt_next_marker(Text *text, TextMarker *marker) {
	TextMarker *tmp= marker;
	while (tmp) {
		if (tmp->next) tmp= tmp->next;
		else tmp= text->markers.first;
		if (tmp->group == marker->group)
			return tmp;
	}
	return NULL; /* Only if marker==NULL */
}


/*******************************/
/* Character utility functions */
/*******************************/

int text_check_bracket(char ch)
{
	int a;
	char opens[] = "([{";
	char close[] = ")]}";

	for(a=0; a<(sizeof(opens)-1); a++) {
		if(ch==opens[a])
			return a+1;
		else if(ch==close[a])
			return -(a+1);
	}
	return 0;
}

int text_check_delim(char ch)
{
	int a;
	char delims[] = "():\"\' ~!%^&*-+=[]{};/<>|.#\t,";

	for(a=0; a<(sizeof(delims)-1); a++) {
		if(ch==delims[a])
			return 1;
	}
	return 0;
}

int text_check_digit(char ch)
{
	if(ch < '0') return 0;
	if(ch <= '9') return 1;
	return 0;
}

int text_check_identifier(char ch)
{
	if(ch < '0') return 0;
	if(ch <= '9') return 1;
	if(ch < 'A') return 0;
	if(ch <= 'Z' || ch == '_') return 1;
	if(ch < 'a') return 0;
	if(ch <= 'z') return 1;
	return 0;
}

int text_check_whitespace(char ch)
{
	if(ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n')
		return 1;
	return 0;
}