commands: add show_chapters_osd command to display chapters on OSD

The command lists the chapters in the current file on the OSD. It also
marks the current chapter.

This is actually a cheap replacement for the chapter select libmenu
functionality.

DOCS/OUTDATED-tech/slave.txt

@@ -493,6 +493,8 @@ vo_rootwin [value]
 volume <value> [abs]
     Increase/decrease volume or set it to <value> if [abs] is nonzero.
 
+show_chapters_osd
+    Show the list of chapters in the currently played file on the OSD.
 
 Available properties:
 

command.c

@@ -2806,6 +2806,44 @@ static void clear_play_tree(MPContext *mpctx)
     do_clear_pt(mpctx->playtree, exclude);
 }
 
+static char *format_time(double time)
+{
+    int h, m, s = time;
+    h = s / 3600;
+    s -= h * 3600;
+    m = s / 60;
+    s -= m * 60;
+    return talloc_asprintf(NULL, "%02d:%02d:%02d", h, m, s);
+}
+
+static void show_chapters_on_osd(MPContext *mpctx)
+{
+    int count = get_chapter_count(mpctx);
+    int cur = mpctx->demuxer ? get_current_chapter(mpctx) : -1;
+    char *res = NULL;
+    int n;
+
+    if (count < 1) {
+        res = talloc_asprintf_append(res, "No chapters.");
+    }
+
+    for (n = 0; n < count; n++) {
+        char *name = chapter_display_name(mpctx, n);
+        double t = chapter_start_time(mpctx, n);
+        char* time = format_time(t);
+        res = talloc_asprintf_append(res, "%s", time);
+        talloc_free(time);
+        char *m1 = "> ", *m2 = " <";
+        if (n != cur)
+            m1 = m2 = "";
+        res = talloc_asprintf_append(res, "   %s%s%s\n", m1, name, m2);
+        talloc_free(name);
+    }
+
+    set_osd_msg(OSD_MSG_TEXT, 1, mpctx->opts.osd_duration, "%s", res);
+    talloc_free(res);
+}
+
 void run_command(MPContext *mpctx, mp_cmd_t *cmd)
 {
     struct MPOpts *opts = &mpctx->opts;
@@ -3622,6 +3660,9 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
             af_reinit(sh_audio->afilter, af);
         }
         break;
+    case MP_CMD_SHOW_CHAPTERS:
+        show_chapters_on_osd(mpctx);
+        break;
 
     default:
         mp_msg(MSGT_CPLAYER, MSGL_V,

input/input.c

@@ -221,6 +221,9 @@ static const mp_cmd_t mp_cmds[] = {
   { MP_CMD_AF_DEL, "af_del", { ARG_STRING } },
   { MP_CMD_AF_CLR, "af_clr", },
   { MP_CMD_AF_CMDLINE, "af_cmdline", { ARG_STRING, ARG_STRING } },
+
+  { MP_CMD_SHOW_CHAPTERS, "show_chapters_osd", },
+
   {0}
 };
 

input/input.h

@@ -153,6 +153,8 @@ enum mp_command_type {
     MP_CMD_AF_DEL,
     MP_CMD_AF_CLR,
     MP_CMD_AF_CMDLINE,
+
+    MP_CMD_SHOW_CHAPTERS,
 };
 
 // The arg types