/*
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1998 Kenneth D. Merry.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/*
 * Copyright (c) 1980, 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */



#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/resource.h>

#include <devstat.h>
#include <err.h>
#include <nlist.h>
#include <paths.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>

#include "systat.h"
#include "extern.h"
#include "devs.h"

static  int linesperregion;
static  double etime;
static  bool numbers = false;           /* default display bar graphs */
static  bool kbpt = false;              /* default ms/seek shown */

static int barlabels(int);
static void histogram(long double, int, double);
static int numlabels(int);
static int devstats(int, int, int);
static void stat1(int, int);

WINDOW *
openiostat(void)
{
        return (subwin(stdscr, LINES-3-1, 0, MAINWIN_ROW, 0));
}

void
closeiostat(WINDOW *w)
{
        if (w == NULL)
                return;
        wclear(w);
        wrefresh(w);
        delwin(w);
}

int
initiostat(void)
{
        /*
         * This value for maxshowdevs (100) is bogus.  I'm not sure exactly
         * how to calculate it, though.
         */
        if (dsinit(7) != 1)
                return(0);

        return(1);
}

void
fetchiostat(void)
{
        struct devinfo *tmp_dinfo;
        size_t len;

        len = sizeof(cur_dev.cp_time);
        if (sysctlbyname("kern.cp_time", &cur_dev.cp_time, &len, NULL, 0)
            || len != sizeof(cur_dev.cp_time)) {
                perror("kern.cp_time");
                exit (1);
        }
        tmp_dinfo = last_dev.dinfo;
        last_dev.dinfo = cur_dev.dinfo;
        cur_dev.dinfo = tmp_dinfo;

        last_dev.snap_time = cur_dev.snap_time;

        /*
         * Here what we want to do is refresh our device stats.
         * getdevs() returns 1 when the device list has changed.
         * If the device list has changed, we want to go through
         * the selection process again, in case a device that we
         * were previously displaying has gone away.
         */
        switch (devstat_getdevs(NULL, &cur_dev)) {
        case -1:
                errx(1, "%s", devstat_errbuf);
                break;
        case 1:
                cmdiostat("refresh", NULL);
                break;
        default:
                break;
        }
        num_devices = cur_dev.dinfo->numdevs;
        generation = cur_dev.dinfo->generation;

}

#define INSET   10

void
labeliostat(void)
{
        int row;

        row = 0;
        wmove(wnd, row, 0); wclrtobot(wnd);
        mvwaddstr(wnd, row++, INSET,
            "/0%  /10  /20  /30  /40  /50  /60  /70  /80  /90  /100");
        mvwaddstr(wnd, row++, 0, "cpu  user|");
        mvwaddstr(wnd, row++, 0, "     nice|");
        mvwaddstr(wnd, row++, 0, "   system|");
        mvwaddstr(wnd, row++, 0, "interrupt|");
        mvwaddstr(wnd, row++, 0, "     idle|");
        if (numbers)
                row = numlabels(row + 1);
        else
                row = barlabels(row + 1);
}

static int
numlabels(int row)
{
        int i, _col, regions, ndrives;
        char tmpstr[32];

#define COLWIDTH        17
#define DRIVESPERLINE   ((getmaxx(wnd) - 1 - INSET) / COLWIDTH)
        for (ndrives = 0, i = 0; i < num_devices; i++)
                if (dev_select[i].selected)
                        ndrives++;
        regions = howmany(ndrives, DRIVESPERLINE);
        /*
         * Deduct -regions for blank line after each scrolling region.
         */
        linesperregion = (getmaxy(wnd) - 1 - row - regions) / regions;
        /*
         * Minimum region contains space for two
         * label lines and one line of statistics.
         */
        if (linesperregion < 3)
                linesperregion = 3;
        _col = INSET;
        for (i = 0; i < num_devices; i++)
                if (dev_select[i].selected) {
                        if (_col + COLWIDTH >= getmaxx(wnd) - 1 - INSET) {
                                _col = INSET, row += linesperregion + 1;
                                if (row > getmaxy(wnd) - 1 - (linesperregion + 1))
                                        break;
                        }
                        snprintf(tmpstr, sizeof(tmpstr), "%s%d", dev_select[i].device_name,
                                dev_select[i].unit_number);
                        mvwaddstr(wnd, row, _col + 4, tmpstr);
                        mvwaddstr(wnd, row + 1, _col, "  KB/t tps  MB/s ");
                        _col += COLWIDTH;
                }
        if (_col)
                row += linesperregion + 1;
        return (row);
}

static int
barlabels(int row)
{
        int i;
        char tmpstr[32];

        mvwaddstr(wnd, row++, INSET,
            "/0%  /10  /20  /30  /40  /50  /60  /70  /80  /90  /100");
        linesperregion = 2 + kbpt;
        for (i = 0; i < num_devices; i++)
                if (dev_select[i].selected) {
                        if (row > getmaxy(wnd) - 1 - linesperregion)
                                break;
                        snprintf(tmpstr, sizeof(tmpstr), "%s%d", dev_select[i].device_name,
                                dev_select[i].unit_number);
                        mvwprintw(wnd, row++, 0, "%-5.5s MB/s|",
                                  tmpstr);
                        mvwaddstr(wnd, row++, 0, "      tps|");
                        if (kbpt)
                                mvwaddstr(wnd, row++, 0, "     KB/t|");
                }
        return (row);
}

void
showiostat(void)
{
        long t;
        int i, row, _col;

#define X(fld)  t = cur_dev.fld[i]; cur_dev.fld[i] -= last_dev.fld[i]; last_dev.fld[i] = t
        etime = 0;
        for(i = 0; i < CPUSTATES; i++) {
                X(cp_time);
                etime += cur_dev.cp_time[i];
        }
        if (etime == 0.0)
                etime = 1.0;
        etime /= hertz;
        row = 1;
        for (i = 0; i < CPUSTATES; i++)
                stat1(row++, i);
        if (!numbers) {
                row += 2;
                for (i = 0; i < num_devices; i++)
                        if (dev_select[i].selected) {
                                if (row > getmaxy(wnd) - linesperregion)
                                        break;
                                row = devstats(row, INSET, i);
                        }
                return;
        }
        _col = INSET;
        wmove(wnd, row + linesperregion, 0);
        wdeleteln(wnd);
        wmove(wnd, row + 3, 0);
        winsertln(wnd);
        for (i = 0; i < num_devices; i++)
                if (dev_select[i].selected) {
                        if (_col + COLWIDTH >= getmaxx(wnd) - 1 - INSET) {
                                _col = INSET, row += linesperregion + 1;
                                if (row > getmaxy(wnd) - 1 - (linesperregion + 1))
                                        break;
                                wmove(wnd, row + linesperregion, 0);
                                wdeleteln(wnd);
                                wmove(wnd, row + 3, 0);
                                winsertln(wnd);
                        }
                        (void) devstats(row + 3, _col, i);
                        _col += COLWIDTH;
                }
}

static int
devstats(int row, int _col, int dn)
{
        long double transfers_per_second;
        long double kb_per_transfer, mb_per_second;
        long double busy_seconds;
        int di;

        di = dev_select[dn].position;

        busy_seconds = cur_dev.snap_time - last_dev.snap_time;

        if (devstat_compute_statistics(&cur_dev.dinfo->devices[di],
            &last_dev.dinfo->devices[di], busy_seconds,
            DSM_KB_PER_TRANSFER, &kb_per_transfer,
            DSM_TRANSFERS_PER_SECOND, &transfers_per_second,
            DSM_MB_PER_SECOND, &mb_per_second, DSM_NONE) != 0)
                errx(1, "%s", devstat_errbuf);

        if (numbers) {
                mvwprintw(wnd, row, _col, " %5.2Lf %3.0Lf %5.2Lf ",
                         kb_per_transfer, transfers_per_second,
                         mb_per_second);
                return(row);
        }
        wmove(wnd, row++, _col);
        histogram(mb_per_second, 50, .5);
        wmove(wnd, row++, _col);
        histogram(transfers_per_second, 50, .5);
        if (kbpt) {
                wmove(wnd, row++, _col);
                histogram(kb_per_transfer, 50, .5);
        }

        return(row);

}

static void
stat1(int row, int o)
{
        int i;
        double dtime;

        dtime = 0.0;
        for (i = 0; i < CPUSTATES; i++)
                dtime += cur_dev.cp_time[i];
        if (dtime == 0.0)
                dtime = 1.0;
        wmove(wnd, row, INSET);
#define CPUSCALE        0.5
        histogram(100.0 * cur_dev.cp_time[o] / dtime, 50, CPUSCALE);
}

static void
histogram(long double val, int colwidth, double scale)
{
        char buf[10];
        int k;
        int v = (int)(val * scale) + 0.5;

        k = MIN(v, colwidth);
        if (v > colwidth) {
                snprintf(buf, sizeof(buf), "%5.2Lf", val);
                k -= strlen(buf);
                while (k--)
                        waddch(wnd, 'X');
                waddstr(wnd, buf);
                return;
        }
        while (k--)
                waddch(wnd, 'X');
        wclrtoeol(wnd);
}

int
cmdiostat(const char *cmd, const char *args)
{

        if (prefix(cmd, "kbpt"))
                kbpt = !kbpt;
        else if (prefix(cmd, "numbers"))
                numbers = true;
        else if (prefix(cmd, "bars"))
                numbers = false;
        else if (!dscmd(cmd, args, 100, &cur_dev))
                return (0);
        wclear(wnd);
        labeliostat();
        refresh();
        return (1);
}