loadfile: truncate long track URL titles

When a track title is a URL longer than 90 characters, truncate it to
not make track information too verbose.

This uses term_disp_width() which is convenient even for ASS output
because it avoids cutting in the middle of UTF-8 characters. So wide
unicode characters will count as 2 characters.

Long track URLs like reported in #10975 no longer flood the terminal
with useless information.

Long track URLs also no longer push track metadata beyond the track
menu, without having to implement UTF-8 aware functions in select.lua to
avoid cutting titles in the middle of UTF-8 characters.

The full URLs are always available in track-list/N/external-filename.

--osd-max-track-title-url-length configures this behavior.

Author: guidocella

DOCS/interface-changes/osd-max-track-title-url-length.txt

@@ -0,0 +1 @@
+add `--osd-track-title-url-max-length`

DOCS/man/options.rst

@@ -4698,6 +4698,13 @@ OSD
 
     Default: ``title``.
 
+``--osd-track-title-url-max-length=<length>``
+    Truncate URL track titles to ``length`` characters. Wide unicode characters
+    count as multiple characters to make this work correctly with terminal
+    output. Set to 0 to disable.
+
+    Default: 90.
+
 ``--osd-bar-align-x=<-1-1>``
     Position of the OSD bar. -1 is far left, 0 is centered, 1 is far right.
     Fractional values (like 0.5) are allowed.

options/options.c

@@ -888,6 +888,8 @@ static const m_option_t mp_opts[] = {
 
     {"osd-playlist-entry", OPT_CHOICE(playlist_entry_name,
         {"title", 0}, {"filename", 1}, {"both", 2})},
+    {"osd-track-title-url-max-length", OPT_INT(max_track_title_url_max_length),
+        M_RANGE(0, INT_MAX)},
 
     {"video-osd", OPT_BOOL(video_osd), .flags = UPDATE_OSD},
 
@@ -999,6 +1001,7 @@ static const struct MPOpts mp_default_opts = {
     .osd_level = 1,
     .osd_on_seek = 1,
     .osd_duration = 1000,
+    .max_track_title_url_max_length = 90,
 #if HAVE_LUA
     .lua_load_osc = true,
     .lua_load_ytdl = true,

options/options.h

@@ -277,6 +277,7 @@ typedef struct MPOpts {
     char *osd_status_msg;
     char *osd_msg[3];
     int playlist_entry_name;
+    int max_track_title_url_max_length;
     int player_idle_mode;
     char **input_commands;
     bool consolecontrols;

player/loadfile.c

@@ -25,6 +25,7 @@
 
 #include "mpv_talloc.h"
 
+#include "misc/codepoint_width.h"
 #include "misc/thread_pool.h"
 #include "misc/thread_tools.h"
 #include "osdep/io.h"
@@ -909,8 +910,18 @@ int mp_add_external_file(struct MPContext *mpctx, char *filename,
             bstr title = bstr0(mp_basename(disp_filename));
             bstr_eatstart(&title, parent);
             bstr_eatstart(&title, bstr0("."));
-            if (title.len)
+
+            const unsigned char *cut_pos = NULL;
+            if (mp_is_url(bstr0(disp_filename))
+                && mpctx->opts->max_track_title_url_max_length)
+                term_disp_width(title, mpctx->opts->max_track_title_url_max_length,
+                                &cut_pos);
+            if (cut_pos) {
+                title.len = cut_pos - title.start;
+                t->title = talloc_asprintf(t, "%.*s\u2026", BSTR_P(title));
+            } else if (title.len) {
                 t->title = bstrdup0(t, title);
+            }
         }
         t->external_filename = mp_normalize_user_path(t, mpctx->global, filename);
         t->no_default = sh->type != filter;