player: fix core-idle and eof-reached update notifcations

Make mpv_observe_property() work correctly on them even with
--keep-open-pause=no.

This also changes the situations in which the screensaver is
enabled/disabled subtly.

player/command.c

@@ -1503,8 +1503,7 @@ static int mp_property_core_idle(void *ctx, struct m_property *prop,
                                  int action, void *arg)
 {
     MPContext *mpctx = ctx;
-    bool idle = mpctx->paused || !mpctx->restart_complete || !mpctx->playing;
-    return m_property_flag_ro(action, arg, idle);
+    return m_property_flag_ro(action, arg, !mpctx->playback_active);
 }
 
 static int mp_property_idle(void *ctx, struct m_property *prop,
@@ -4093,8 +4092,8 @@ static const char *const *const mp_event_property_change[] = {
     E(MPV_EVENT_TRACK_SWITCHED, "vid", "video", "aid", "audio", "sid", "sub",
       "secondary-sid"),
     E(MPV_EVENT_IDLE, "*"),
-    E(MPV_EVENT_PAUSE,   "pause", "paused-on-cache", "core-idle", "eof-reached"),
-    E(MPV_EVENT_UNPAUSE, "pause", "paused-on-cache", "core-idle", "eof-reached"),
+    E(MPV_EVENT_PAUSE,   "pause"),
+    E(MPV_EVENT_UNPAUSE, "pause"),
     E(MPV_EVENT_TICK, "time-pos", "audio-pts", "stream-pos", "avsync",
       "percent-pos", "time-remaining", "playtime-remaining", "playback-time",
       "estimated-vf-fps", "drop-frame-count", "vo-drop-frame-count",
@@ -4126,6 +4125,7 @@ static const char *const *const mp_event_property_change[] = {
       "fullscreen"),
     E(MP_EVENT_CHANGE_PLAYLIST, "playlist", "playlist-pos", "playlist-pos-1",
       "playlist-count", "playlist/count"),
+    E(MP_EVENT_CORE_IDLE, "core-idle", "eof-reached"),
 };
 #undef E
 

player/command.h

@@ -56,6 +56,7 @@ enum {
     MP_EVENT_WIN_RESIZE,
     MP_EVENT_WIN_STATE,
     MP_EVENT_CHANGE_PLAYLIST,
+    MP_EVENT_CORE_IDLE,
 };
 
 bool mp_hook_test_completion(struct MPContext *mpctx, char *type);

player/core.h

@@ -415,7 +415,9 @@ typedef struct MPContext {
     int last_chapter_seek;
     double last_chapter_pts;
 
-    bool paused;
+    bool paused;            // internal pause state
+    bool playback_active;   // not paused, restarting, loading, unloading
+
     // step this many frames, then pause
     int step_frames;
     // Counted down each frame, stop playback if 0 is reached. (-1 = disable)
@@ -560,6 +562,7 @@ double get_relative_time(struct MPContext *mpctx);
 void reset_playback_state(struct MPContext *mpctx);
 void set_pause_state(struct MPContext *mpctx, bool user_pause);
 void update_internal_pause_state(struct MPContext *mpctx);
+void update_core_idle_state(struct MPContext *mpctx);
 void add_step_frame(struct MPContext *mpctx, int dir);
 void queue_seek(struct MPContext *mpctx, enum seek_type type, double amount,
                 enum seek_precision exact, int flags);

player/loadfile.c

@@ -1281,6 +1281,9 @@ reopen_file:
 
 terminate_playback:
 
+    mpctx->playback_active = false;
+    update_core_idle_state(mpctx);
+
     process_unload_hooks(mpctx);
 
     if (mpctx->stop_play == KEEP_PLAYING)
@@ -1306,7 +1309,6 @@ terminate_playback:
         uninit_audio_out(mpctx);
 
     mpctx->playback_initialized = false;
-    update_screensaver_state(mpctx);
 
     if (mpctx->stop_play == PT_RELOAD_FILE) {
         mpctx->stop_play = KEEP_PLAYING;

player/playloop.c

@@ -120,6 +120,22 @@ double get_relative_time(struct MPContext *mpctx)
     return delta * 0.000001;
 }
 
+void update_core_idle_state(struct MPContext *mpctx)
+{
+    bool eof = mpctx->video_status == STATUS_EOF &&
+               mpctx->audio_status == STATUS_EOF;
+    bool active =
+        !mpctx->paused && mpctx->restart_complete && mpctx->playing && !eof;
+
+    if (mpctx->playback_active != active) {
+        mpctx->playback_active = active;
+
+        update_screensaver_state(mpctx);
+
+        mp_notify(mpctx, MP_EVENT_CORE_IDLE, NULL);
+    }
+}
+
 // The value passed here is the new value for mpctx->opts->pause
 void set_pause_state(struct MPContext *mpctx, bool user_pause)
 {
@@ -159,10 +175,10 @@ void set_pause_state(struct MPContext *mpctx, bool user_pause)
         }
     }
 
-    if (send_update) {
-        update_screensaver_state(mpctx);
+    update_core_idle_state(mpctx);
+
+    if (send_update)
         mp_notify(mpctx, opts->pause ? MPV_EVENT_PAUSE : MPV_EVENT_UNPAUSE, 0);
-    }
 }
 
 void update_internal_pause_state(struct MPContext *mpctx)
@@ -175,8 +191,7 @@ void update_screensaver_state(struct MPContext *mpctx)
     if (!mpctx->video_out)
         return;
 
-    bool saver_state = mpctx->opts->pause || !mpctx->opts->stop_screensaver ||
-                       !mpctx->playback_initialized;
+    bool saver_state = !mpctx->playback_active || !mpctx->opts->stop_screensaver;
     vo_control_async(mpctx->video_out, saver_state ? VOCTRL_RESTORE_SCREENSAVER
                                                    : VOCTRL_KILL_SCREENSAVER, NULL);
 }
@@ -227,6 +242,8 @@ void reset_playback_state(struct MPContext *mpctx)
 #if HAVE_ENCODING
     encode_lavc_discontinuity(mpctx->encode_lavc_ctx);
 #endif
+
+    update_core_idle_state(mpctx);
 }
 
 static void mp_seek(MPContext *mpctx, struct seek_params seek)
@@ -980,6 +997,7 @@ static void handle_playback_restart(struct MPContext *mpctx)
         mpctx->audio_allow_second_chance_seek = false;
         handle_playback_time(mpctx);
         mp_notify(mpctx, MPV_EVENT_PLAYBACK_RESTART, NULL);
+        update_core_idle_state(mpctx);
         if (!mpctx->playing_msg_shown) {
             if (opts->playing_msg && opts->playing_msg[0]) {
                 char *msg =
@@ -1103,6 +1121,8 @@ void run_playloop(struct MPContext *mpctx)
 
     handle_sstep(mpctx);
 
+    update_core_idle_state(mpctx);
+
     if (mpctx->stop_play)
         return;