* emms-player-mpv.el: fix reconnect-playback-restart issue from d4d9171

Adds ability to send/queue batched commands, so that multiple commands
can be re-queued after restarting dead mpv process, not just the last one,
which was the problem with adding unpause command after loadfile.

1 files changed, 42 insertions, 35 deletions

diff --git a/emms-player-mpv.el b/emms-player-mpv.el
index bc5b2d8..b562147 100644
--- a/emms-player-mpv.el
+++ b/emms-player-mpv.el
@@ -571,24 +571,35 @@ HANDLER func will be called with decoded response JSON as (handler data err),
 where ERR will be either nil on \"success\", 'connection-error or whatever is in JSON.
 If HANDLER is nil, default `emms-player-mpv-ipc-req-error-printer'
 will be used to at least log errors.
+Multiple commands can be batched in one list as '(batch (cmd1 . handler1) ...),
+in which case common HANDLER argument is ignored.
 PROC can be specified to avoid `emms-player-mpv-ipc' call (e.g. from sentinel/filter funcs)."
-  (let
-      ((req-id (emms-player-mpv-ipc-id-get))
-       (req-proc (or proc (emms-player-mpv-ipc)))
-       (handler (or handler #'emms-player-mpv-ipc-req-error-printer)))
-    (unless emms-player-mpv-ipc-req-table
-      (setq emms-player-mpv-ipc-req-table (make-hash-table)))
-    (let ((json (concat (json-encode (list :command cmd :request_id req-id))
-                        "\n")))
-      (emms-player-mpv-debug-msg "json >> %s" json)
-      (condition-case _err
-          ;; On any disconnect, assume that mpv process is to blame and force restart.
-          (process-send-string req-proc json)
-        (error
-         (emms-player-mpv-proc-stop)
-         (funcall handler nil 'connection-error)
-         (setq handler nil))))
-    (when handler (puthash req-id handler emms-player-mpv-ipc-req-table))))
+  (dolist
+      (cmd-and-handler
+       (if (and (listp cmd)
+                (eq (car cmd)
+                    'batch))
+           (cdr cmd)
+         `((,cmd . ,handler))))
+    (cl-destructuring-bind (cmd . handler)
+        cmd-and-handler
+      (let
+          ((req-id (emms-player-mpv-ipc-id-get))
+           (req-proc (or proc (emms-player-mpv-ipc)))
+           (handler (or handler #'emms-player-mpv-ipc-req-error-printer)))
+        (unless emms-player-mpv-ipc-req-table
+          (setq emms-player-mpv-ipc-req-table (make-hash-table)))
+        (let ((json (concat (json-encode (list :command cmd :request_id req-id))
+                            "\n")))
+          (emms-player-mpv-debug-msg "json >> %s" json)
+          (condition-case _err
+              ;; On any disconnect, assume that mpv process is to blame and force restart.
+              (process-send-string req-proc json)
+            (error
+             (emms-player-mpv-proc-stop)
+             (funcall handler nil 'connection-error)
+             (setq handler nil))))
+        (when handler (puthash req-id handler emms-player-mpv-ipc-req-table))))))
 
 (defun emms-player-mpv-ipc-req-resolve (req-id data err)
   "Run handler-func for specified req-id."
@@ -764,7 +775,9 @@ Called before `emms-player-mpv-event-functions' and does same thing as these hoo
 (defun emms-player-mpv-cmd (cmd &optional handler)
   "Send mpv command to process/connection if both are running,
 or otherwise schedule start/connect and set
-`emms-player-mpv-ipc-start-track' for `emms-player-mpv-ipc-sentinel'."
+`emms-player-mpv-ipc-connect-command' for `emms-player-mpv-ipc-sentinel'.
+Multiple commands can be batched in one list as '(batch (cmd1 . handler1) ...),
+in which case common HANDLER argument is ignored."
   (setq emms-player-mpv-ipc-connect-command nil)
   (let ((proc (emms-player-mpv-ipc)))
     (if proc
@@ -795,17 +808,6 @@ and will be removed in a future EMMS version."
   (memq (emms-track-type track)
         '(file url streamlist playlist)))
 
-(defun emms-player-mpv-start-error-handler (mpv-cmd _mpv-data mpv-error)
-  "Playback-restart error handler for `emms-player-mpv-cmd',
-to restart/reconnect-to mpv and re-run MPV-CMD,
-if there was any issue when trying to start it initially."
-  (if (eq mpv-error 'connection-error)
-      ;; Reconnect and restart playback if current connection fails (e.g. mpv crash)
-      (emms-player-mpv-cmd mpv-cmd
-                           (lambda (_mpv-data _mpv-error)
-                             (emms-player-mpv-cmd mpv-cmd)
-                             (emms-player-mpv-cmd '(set pause no))))))
-
 (defun emms-player-mpv-start (track)
   (setq emms-player-mpv-stopped nil)
   (emms-player-mpv-proc-playing nil)
@@ -821,12 +823,17 @@ if there was any issue when trying to start it initially."
                                      track-name)
           (emms-player-started emms-player-mpv))
       (let*
-          ((start-cmd (list (if track-is-playlist 'loadlist 'loadfile)
-                            track-name 'replace))
-           (start-func (lambda ()
-                          (emms-player-mpv-cmd start-cmd
-                                               (apply-partially #'emms-player-mpv-start-error-handler start-cmd))
-                          (emms-player-mpv-cmd '(set pause no)))))
+          ((play-cmd
+            `(batch
+              ((,(if track-is-playlist 'loadlist 'loadfile)
+                ,track-name replace))
+              ((set pause no))))
+           (start-func
+            ;; Try running play-cmd and retry it on connection failure, e.g. if mpv died
+            (apply-partially 'emms-player-mpv-cmd play-cmd
+                             (lambda (_mpv-data mpv-error)
+                               (when (eq mpv-error 'connection-error)
+                                 (emms-player-mpv-cmd play-cmd))))))
         (if emms-player-mpv-ipc-stop-command
             (setq emms-player-mpv-ipc-stop-command start-func)
           (funcall start-func))))))