src/hscroll.c

   1 /* ncmpc (Ncurses MPD Client)
   2  * (c) 2004-2010 The Music Player Daemon Project
   3  * Project homepage: http://musicpd.org
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #include "hscroll.h"
  21 #include "charset.h"
  22 #include "ncfix.h"
  23 #include "glib_compat.h"
  24
  25 #include <assert.h>
  26 #include <string.h>
  27
  28 char *
  29 strscroll(struct hscroll *hscroll, const char *str, const char *separator,
  30           unsigned width)
  31 {
  32         gchar *tmp, *buf;
  33
  34         assert(hscroll != NULL);
  35         assert(str != NULL);
  36         assert(separator != NULL);
  37
  38         /* create a buffer containing the string and the separator */
  39         tmp = replace_locale_to_utf8(g_strconcat(str, separator,
  40                                                  str, separator, NULL));
  41
  42         if (hscroll->offset >= (unsigned)g_utf8_strlen(tmp, -1) / 2)
  43                 hscroll->offset = 0;
  44
  45         /* create the new scrolled string */
  46         buf = g_utf8_offset_to_pointer(tmp, hscroll->offset);
  47         utf8_cut_width(buf, width);
  48
  49         /* convert back to locale */
  50         buf = utf8_to_locale(buf);
  51         g_free(tmp);
  52         return buf;
  53 }
  54
  55 /**
  56  * This timer scrolls the area by one and redraws.
  57  */
  58 static gboolean
  59 hscroll_timer_callback(gpointer data)
  60 {
  61         struct hscroll *hscroll = data;
  62
  63         hscroll_step(hscroll);
  64         hscroll_draw(hscroll);
  65         wrefresh(hscroll->w);
  66         return true;
  67 }
  68
  69 void
  70 hscroll_set(struct hscroll *hscroll, unsigned x, unsigned y, unsigned width,
  71             const char *text)
  72 {
  73         assert(hscroll != NULL);
  74         assert(hscroll->w != NULL);
  75         assert(text != NULL);
  76
  77         if (hscroll->text != NULL && hscroll->x == x && hscroll->y == y &&
  78             hscroll->width == width && strcmp(hscroll->text, text) == 0)
  79                 /* no change, do nothing (and, most importantly, do
  80                    not reset the current offset!) */
  81                 return;
  82
  83         hscroll_clear(hscroll);
  84
  85         hscroll->x = x;
  86         hscroll->y = y;
  87         hscroll->width = width;
  88
  89         /* obtain the ncurses attributes and the current color, store
  90            them */
  91         fix_wattr_get(hscroll->w, &hscroll->attrs, &hscroll->pair, NULL);
  92
  93         hscroll->text = g_strdup(text);
  94         hscroll->offset = 0;
  95         hscroll->source_id = g_timeout_add_seconds(1, hscroll_timer_callback,
  96                                                    hscroll);
  97 }
  98
  99 void
 100 hscroll_clear(struct hscroll *hscroll)
 101 {
 102         assert(hscroll != NULL);
 103
 104         if (hscroll->text == NULL)
 105                 return;
 106
 107         g_source_remove(hscroll->source_id);
 108
 109         g_free(hscroll->text);
 110         hscroll->text = NULL;
 111 }
 112
 113 void
 114 hscroll_draw(struct hscroll *hscroll)
 115 {
 116         attr_t old_attrs;
 117         short old_pair;
 118         char *p;
 119
 120         assert(hscroll != NULL);
 121         assert(hscroll->w != NULL);
 122         assert(hscroll->text != NULL);
 123
 124         /* set stored attributes and color */
 125         fix_wattr_get(hscroll->w, &old_attrs, &old_pair, NULL);
 126         wattr_set(hscroll->w, hscroll->attrs, hscroll->pair, NULL);
 127
 128         /* scroll the string, and draw it */
 129         p = strscroll(hscroll, hscroll->text, hscroll->separator,
 130                       hscroll->width);
 131         mvwaddstr(hscroll->w, hscroll->y, hscroll->x, p);
 132         g_free(p);
 133
 134         /* restore previous attributes and color */
 135         wattr_set(hscroll->w, old_attrs, old_pair, NULL);
 136 }