/*************************************************************
 * File: mon/hist.c
 * Purpose: Part of core Monitor
 * Author: Phil Bunce (pjb@carmel.com)
 * Revision History:
 *	970304	Start of revision history
 *	971002	Made some functions static
 *	971002	Fixed probs with ^N and ^P past end/beginning of history
 *	980331	changed getchar to GETCHAR for imon95
 */

#include <stdio.h>
#include <termio.h>
#include <string.h>
#include <mon.h>

#ifdef PMCC
#define GETCHAR getchar
#endif

#define H_PREV	CNTRL('P')
#define H_NEXT	CNTRL('N')
#define H_FORW	CNTRL('F')
#define H_BACK	CNTRL('B')
#define H_BEGIN	CNTRL('A')
#define H_END	CNTRL('E')
#define H_DELETE	CNTRL('D')

char *hist[HISTMAX];	/* array of old commands */

int histi;	/* index to hist[], indicates next slot */
int histo;	/* index to hist[], indicates oldest entry */
int histr;	/* index to hist[], used while walking back with H_PREV */
int histno;	/* current history number */
int column;	/* current column number */

char *gethistn(),*gethists();
static left(), right(), backspace(), putstr(); /* 971002 */
void addhist(),addchar();

/*************************************************************
*  histinit() 
*	initialize history mechanism
*/
histinit()
{

histno = 1;
}

/*************************************************************
*  get_cmd(p) 
*	get a line from stdin using lineedit and history
*/
get_cmd(p)
char *p;
{
int c,oc,v,i;
char *q,buf[20],*t;

ioctl_cbreak(STDIN);
*p = 0;
histr = histi;
column = 0;
for (;;) {
	c = GETCHAR();
	if (c == H_PREV) {
		if (histr != histo) {
			right(p,strlen(p)-column);
			backspace(column);
			histr = decmod(histr,HISTMAX);
			strcpy(p,hist[histr]);
			putstr(p);
			}
		}
	else if (c == H_NEXT) {
		if (histr != histi) {
			right(p,strlen(p)-column);
			backspace(column);
			histr = incmod(histr,HISTMAX);
			if (histr == histi) *p = 0;
			else strcpy(p,hist[histr]);
			putstr(p);
			}
		}
	else if (c == H_FORW) right(p,1);
	else if (c == H_BACK) left(1);
	else if (c == H_BEGIN) left(column);
	else if (c == H_END) right(p,strlen(&p[column]));
	else if (c == H_DELETE) {
		oc = column;
		strdchr(&p[column]);
		putstr(&p[column]);
		putstr(" ");
		left(strlen(&p[oc])+1);
		}
	else if (c == '\b') {
		left(1);
		oc = column;
		strdchr(&p[column]);
		putstr(&p[column]);
		putstr(" ");
		left(strlen(&p[oc])+1);
		}
	else if (c == '\n' || c == '\r') {
		putstr("\n");
		break;
		}
	else addchar(p,c);
	}

/* do C-shell history subs */
if (q = findbang(p)) {
	getword(buf,q);
	strdchr(buf); /* delete the bang */
	if (!strempty(buf)) {
		for (i=strlen(buf)+1;i>0;i--) strdchr(q);
		if (strequ(buf,"!")) { /* repeat last cmd */
			stristr(q,hist[decmod(histi,HISTMAX)]);
			printf("%s\n",p);
			}
		else if (atob(&v,buf,10)) { /* hist# */
			if (t = gethistn(v)) {
				stristr(q,t);
				printf("%s\n",p);
				}
			else printf("%s: Event not found.\n",buf);
			}
		else { /* hist string */
			if (t = gethists(buf)) {
				stristr(q,t);
				printf("%s\n",p);
				}
			else printf("%s: Event not found.\n",buf);
			}
		}
	}
addhist(p);
ioctl_restore(STDIN);
}

/*************************************************************
*  void addchar(p,c) 
*	add char to line, updates 'column'
*/
void addchar(p,c)
char *p;
int c;
{
int oc;

if (strlen(p) > LINESZ-40) return;
oc = column;
strichr(&p[column],c);
putstr(&p[column]);
left(strlen(&p[oc])-1);
}

Optdesc hi_opts[] = {
	{"[cnt]","display command history"},
	{"cnt","list cnt lines of command history"},
	{0}};

/*************************************************************
*  dohi() 
*	The hi command
*/
dohi(ac,av)
int ac;
char *av[];
{
int i,n,siz,l;
U64 rv;

if(ac == 2) {
	if(!get_rsa(&rv,av[1])) return(1);
	siz = rv.lo;
	}
else {
	if (!atob(&siz,getMonEnv("moresz"),10)) {
		printf("%s: bad moresz value\n",getMonEnv("moresz"));
		return(1);
		}
	}

ioctl_cbreak(STDIN);
l = siz;
i = decmod(histi,HISTMAX);
n = histno-1;
while (i != decmod(histo,HISTMAX)) {
	sprintf(prnbuf,"%5d  %s",n,hist[i]);
	if (more(prnbuf,&l,(ac>1)?0:siz)) break;
	i = decmod(i,HISTMAX);
	n--;
	}
return(0);
}

/*************************************************************
*  static backspace(n) 
*	distructive backspace, updates 'column'
*/
static backspace(n)
int n;
{

for (;n>0 && column > 0;n--) {
	printf("\b \b");
	column--;
	}
}

/*************************************************************
*  static right(p,n) 
*	move the cursor n places right, updates global 'column'
*/
static right(p,n)
char *p;
int n;
{
int len;

len = strlen(p);
for (;n>0 && column < len;n--) {
	putchar(p[column]);
	column++;
	}
}

/*************************************************************
*  static left(n) 
*	move the cursor n places left, updating global 'column'
*/
static left(n)
int n;
{

for (;n>0 && column > 0;n--) {
	putchar('\b');
	column--;
	}
}

/*************************************************************
*  char *gethistn(n) 
*	return ptr to hist entry n
*/
char *gethistn(n)
int n;
{
int m,d;

if (n < (histno - HISTMAX) || n > histno) return(0);
m = histi;
d = histno - n;
for (;d>0;d--) m = decmod(m,HISTMAX);
return(hist[m]);
}

/*************************************************************
*  char *gethists(p) 
*	use strbequ to return ptr to matching hist string
*/
char *gethists(p)
char *p;
{
int i;

i = decmod(histi,HISTMAX);
while (i != decmod(histo,HISTMAX)) {
	if (hist[i] == 0) break;
	if (strbequ(hist[i],p)) return(hist[i]);
	i = decmod(i,HISTMAX);
	}
return(0);
}

/*************************************************************
*  void addhist(p) 
*	add command line to history
*/
void addhist(p)
char *p;
{
int i;

/* discard empty lines */
if (strempty(p)) return;

/* discard dup lines if adjacent */
i = decmod(histi,HISTMAX);
if (hist[i] != 0) {
	if (strequ(p,hist[i])) return;
	}

/* make space if input has reached output */
if (incmod(histi,HISTMAX) == histo) {
	if (hist[histo] != 0) free(hist[histo]);
	hist[histo] = 0;
	histo = incmod(histo,HISTMAX);
	}
hist[histi] = (char *)malloc(strlen(p)+1);
if (hist[histi] == 0) {
	printf("addhist: out of memory\n");
	return;
	}
strcpy(hist[histi],p);
histi = incmod(histi,HISTMAX);
histno++;
}

/*************************************************************
*  static putstr(p) 
*	print string and update global 'column'
*/
static putstr(p)
char *p;
{
int i;

for (i=0;p[i] != 0;i++) {
	if (!noecho) putchar(p[i]);
	if (noecho && xvwmode && p[i] == '\n') putchar('\n');
	if (p[i] == '\n') column = 0;
	else column++;
	}
}

/*************************************************************
*  char *findbang(p)
*	Find the bang character (!). Skips stuff inside quotes.
*/
char *findbang(p)
char *p;
{
int quote;

for (;*p;p++) {
	if (*p == '\'' || *p == '"') {
		quote = *p;
		p++;
		while (*p && *p != quote) p++;
		}
	else if (*p == '!') return(p);
	}
return(0);
}