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 "glib_compat.h"
  23
  24 #include <assert.h>
  25 #include <string.h>
  26
  27 char *
  28 strscroll(struct hscroll *hscroll, const char *str, const char *separator,
  29           unsigned width)
  30 {
  31         gchar *tmp, *buf;
  32
  33         assert(hscroll != NULL);
  34         assert(str != NULL);
  35         assert(separator != NULL);
  36
  37         /* create a buffer containing the string and the separator */
  38         tmp = replace_locale_to_utf8(g_strconcat(str, separator,
  39                                                  str, separator, NULL));
  40
  41         if (hscroll->offset >= (unsigned)g_utf8_strlen(tmp, -1) / 2)
  42                 hscroll->offset = 0;
  43
  44         /* create the new scrolled string */
  45         buf = g_utf8_offset_to_pointer(tmp, hscroll->offset);
  46         utf8_cut_width(buf, width);
  47
  48         /* convert back to locale */
  49         buf = utf8_to_locale(buf);
  50         g_free(tmp);
  51         return buf;
  52 }
  53
  54 /**
  55  * This timer scrolls the area by one and redraws.
  56  */
  57 static gboolean
  58 hscroll_timer_callback(gpointer data)
  59 {
  60         struct hscroll *hscroll = data;
  61
  62         hscroll_step(hscroll);
  63         hscroll_draw(hscroll);
  64         wrefresh(hscroll->w);
  65         return true;
  66 }
  67
  68 void
  69 hscroll_set(struct hscroll *hscroll, unsigned x, unsigned y, unsigned width,
  70             const char *text)
  71 {
  72         assert(hscroll != NULL);
  73         assert(hscroll->w != NULL);
  74         assert(text != NULL);
  75
  76         if (hscroll->text != NULL && hscroll->x == x && hscroll->y == y &&
  77             hscroll->width == width && strcmp(hscroll->text, text) == 0)
  78                 /* no change, do nothing (and, most importantly, do
  79                    not reset the current offset!) */
  80                 return;
  81
  82         hscroll_clear(hscroll);
  83
  84         hscroll->x = x;
  85         hscroll->y = y;
  86         hscroll->width = width;
  87
  88         /* obtain the ncurses attributes and the current color, store
  89            them */
  90         wattr_get(hscroll->w, &hscroll->attrs, &hscroll->pair, NULL);
  91
  92         hscroll->text = g_strdup(text);
  93         hscroll->offset = 0;
  94         hscroll->source_id = g_timeout_add_seconds(1, hscroll_timer_callback,
  95                                                    hscroll);
  96 }
  97
  98 void
  99 hscroll_clear(struct hscroll *hscroll)
 100 {
 101         assert(hscroll != NULL);
 102
 103         if (hscroll->text == NULL)
 104                 return;
 105
 106         g_source_remove(hscroll->source_id);
 107
 108         g_free(hscroll->text);
 109         hscroll->text = NULL;
 110 }
 111
 112 void
 113 hscroll_draw(struct hscroll *hscroll)
 114 {
 115         attr_t old_attrs;
 116         short old_pair;
 117         char *p;
 118
 119         assert(hscroll != NULL);
 120         assert(hscroll->w != NULL);
 121         assert(hscroll->text != NULL);
 122
 123         /* set stored attributes and color */
 124         wattr_get(hscroll->w, &old_attrs, &old_pair, NULL);
 125         wattr_set(hscroll->w, hscroll->attrs, hscroll->pair, NULL);
 126
 127         /* scroll the string, and draw it */
 128         p = strscroll(hscroll, hscroll->text, hscroll->separator,
 129                       hscroll->width);
 130         mvwaddstr(hscroll->w, hscroll->y, hscroll->x, p);
 131         g_free(p);
 132
 133         /* restore previous attributes and color */
 134         wattr_set(hscroll->w, old_attrs, old_pair, NULL);
 135 }