/*
 * Copyright (C) 1999-2005, Michael Jennings
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies of the Software, its documentation and marketing & publicity
 * materials, and acknowledgment shall be given in the documentation, materials
 * and software packages that this Software was used.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include "config.h"
#include "epplet.h"

#if 0
#define D(x) do {printf("%10s | %7d:  [debug] ", __FILE__, __LINE__); printf x; fflush(stdout);} while (0)
#else
#define D(x) ((void) 0)
#endif
#define BEGMATCH(a, b)  (!strncasecmp((a), (b), (sizeof(b) - 1)))
#define NONULL(x)       ((x) ? (x) : (""))

static Epplet_gadget close_button, in_bar, out_bar, in_label, out_label, title,
    cfg_button;
static int      in_val = 0, out_val = 0;
static unsigned long max_in = 1, max_out = 1;
static unsigned char show_title = 1;

static void
show_size(unsigned long n, char *buff)
{
    if (n < 1024)
    {
        sprintf(buff, "%lu b", n);
    }
    else if (n < 1024 * 1024)
    {
        sprintf(buff, "%lu k", n / 1024);
    }
    else if (n < 1024 * 1024 * 1024)
    {
        sprintf(buff, "%lu M", n / (1024 * 1024));
    }
    else
    {
        sprintf(buff, "%lu G", n / (1024 * 1024 * 1024));
    }
}

static void
timer_cb(void *data __UNUSED__)
{
    FILE           *fp;
    char            buff[1024];
    unsigned long   a, b, c, d, e;
    unsigned long   in_blks = 0, out_blks = 0;
    static unsigned long last_in = 0, last_out = 0, in_delta = 0, out_delta = 0;

    if (!(fp = fopen("/proc/diskstats", "r")))
    {
        if (!(fp = fopen("/proc/stat", "r")))
        {
            D(("Failed to open /proc/stat -- %s\n", strerror(errno)));
            return;
        }
    }

    for (; fgets(buff, sizeof(buff), fp);)
    {
        if (BEGMATCH(buff, "disk_rblk"))
        {
            sscanf(buff, "%*s %lu %lu %lu %lu", &a, &b, &c, &d);
            in_blks = a + b + c + d;
            fgets(buff, sizeof(buff), fp);
            sscanf(buff, "%*s %lu %lu %lu %lu", &a, &b, &c, &d);
            out_blks = a + b + c + d;
        }
        else if (BEGMATCH(buff, "disk_io"))
        {
            char           *pbuff = buff + 9;

            for (in_blks = out_blks = 0; *pbuff == '(';
                 pbuff = strchr(pbuff, ' ') + 1)
            {
                pbuff = strchr(++pbuff, '(');
                sscanf(++pbuff, "%lu,%lu,%lu,%lu,%lu", &a, &b, &c, &d, &e);
                in_blks += c;
                out_blks += e;
            }
        }
        else
        {
            char            tmp[64];

            /* Hopefully no one can exploit /proc/diskstats without root. :-) */
            sscanf(buff, "%lu %lu %s %*u %*u %lu %*u %*u %*u %lu", &a, &b, tmp,
                   &c, &d);
            /* Check for hdX or sdX, or md#, or...??? */
            if (((*tmp == 'h' || *tmp == 's') && tmp[1] == 'd' &&
                 isalpha(tmp[2]) && tmp[3] == 0) ||
                (*tmp == 'm' && tmp[1] == 'd' && isdigit(tmp[2])))
            {
                in_blks += c;
                out_blks += d;
            }
        }
    }
    in_blks -= last_in;
    out_blks -= last_out;
    fclose(fp);

    if (last_in)
    {
        /* We must have some history data to do anything. */
        if (in_blks > max_in)
        {
            max_in = in_blks;
            snprintf(buff, sizeof(buff), "%lu", max_in);
            Epplet_modify_config("max_in", buff);
        }
        if (in_blks != in_delta)
        {
            in_val = (int)((((float)in_blks) / max_in) * 100.0);
            Epplet_gadget_data_changed(in_bar);
            sprintf(buff, "I: ");
            show_size(in_blks * 512, buff + 3);
            strcat(buff, "/s");
            Epplet_change_label(in_label, buff);
        }
        in_delta = in_blks;
    }
    last_in += in_blks;

    if (last_out)
    {
        /* We must have some history data to do anything. */
        if (out_blks > max_out)
        {
            max_out = out_blks;
            snprintf(buff, sizeof(buff), "%lu", max_out);
            Epplet_modify_config("max_out", buff);
        }
        if (out_blks != out_delta)
        {
            out_val = (int)((((float)out_blks) / max_out) * 100.0);
            Epplet_gadget_data_changed(out_bar);
            sprintf(buff, "O: ");
            show_size(out_blks * 512, buff + 3);
            strcat(buff, "/s");
            Epplet_change_label(out_label, buff);
        }
        out_delta = out_blks;
    }
    last_out += out_blks;

    Esync();
    Epplet_timer(timer_cb, NULL, 1.0, "TIMER");
}

static void
close_cb(void *data __UNUSED__)
{
    Epplet_Exit(0);
}

static void
title_cb(void *data __UNUSED__)
{
    show_title = !show_title;
    if (show_title)
    {
        Epplet_gadget_move(in_label, 3, 13);
        Epplet_gadget_move(out_label, 3, 30);
        Epplet_gadget_move(in_bar, 3, 22);
        Epplet_gadget_move(out_bar, 3, 39);
        Epplet_gadget_show(title);
    }
    else
    {
        Epplet_gadget_move(in_label, 4, 4);
        Epplet_gadget_move(out_label, 4, 24);
        Epplet_gadget_move(in_bar, 4, 14);
        Epplet_gadget_move(out_bar, 4, 36);
        Epplet_gadget_hide(title);
    }
    Epplet_modify_config("title", (show_title ? "1" : "0"));
    Epplet_redraw();
}

static void
in_cb(void *data __UNUSED__, Window w)
{
    if (w == Epplet_get_main_window())
    {
        Epplet_gadget_show(close_button);
        Epplet_gadget_show(cfg_button);
    }
}

static void
out_cb(void *data __UNUSED__, Window w)
{
    if (w == Epplet_get_main_window())
    {
        Epplet_gadget_hide(close_button);
        Epplet_gadget_hide(cfg_button);
    }
}

static void
parse_conf(void)
{
    const char     *s;

    s = Epplet_query_config("max_in");
    if (s)
        max_in = strtoul(s, (char **)NULL, 10);

    s = Epplet_query_config("max_out");
    if (s)
        max_out = strtoul(s, (char **)NULL, 10);

    show_title = atoi(Epplet_query_config_def("title", "1"));
}

int
main(int argc, char **argv)
{
    Epplet_adjust_priority(10);

    Epplet_Init("E-Disk", "0.2", "Enlightenment Disk I/O Monitor Epplet", 3, 3,
                argc, argv, 0);
    Epplet_load_config();
    parse_conf();

    title = Epplet_create_label(3, 3, "Disk I/O", 1);
    if (show_title)
    {
        /* New arrangement */
        in_label = Epplet_create_label(3, 13, "I: 0 b/s", 1);
        out_label = Epplet_create_label(3, 30, "O: 0 b/s", 1);
        in_bar = Epplet_create_hbar(3, 22, 42, 7, 0, &in_val);
        out_bar = Epplet_create_hbar(3, 39, 42, 7, 0, &out_val);
        Epplet_gadget_show(title);
    }
    else
    {
        /* Old arrangement */
        in_label = Epplet_create_label(4, 4, "I: 0 b/s", 1);
        out_label = Epplet_create_label(4, 24, "O: 0 b/s", 1);
        in_bar = Epplet_create_hbar(4, 14, 40, 8, 0, &in_val);
        out_bar = Epplet_create_hbar(4, 36, 40, 8, 0, &out_val);
    }
    close_button =
        Epplet_create_button(NULL, NULL, 2, 2, 0, 0, "CLOSE", 0, NULL, close_cb,
                             NULL);
    cfg_button =
        Epplet_create_button(NULL, NULL, 33, 2, 0, 0, "CONFIGURE", 0, NULL,
                             title_cb, NULL);
    Epplet_gadget_show(in_label);
    Epplet_gadget_show(in_bar);
    Epplet_gadget_show(out_label);
    Epplet_gadget_show(out_bar);
    Epplet_show();

    Epplet_register_focus_in_handler(in_cb, NULL);
    Epplet_register_focus_out_handler(out_cb, NULL);
    timer_cb(NULL);             /* Set everything up */
    Epplet_Loop();

    return 0;
}