command, lua: change script_message semantics

Change script_message to broadcast the message to all clients. Add a new
script_message_to command, which does what the old script_message
command did.

This is intended as simplification, although it might lead to chaos too.

2 files changed, 29 insertions, 14 deletions

diff --git a/DOCS/man/en/input.rst b/DOCS/man/en/input.rst
index f5efb1f49e..5dabc72761 100644
--- a/DOCS/man/en/input.rst
+++ b/DOCS/man/en/input.rst
@@ -443,13 +443,20 @@ Input Commands that are Possibly Subject to Change
     Remove an overlay added with ``overlay_add`` and the same ID. Does nothing
     if no overlay with this ID exists.
 
-``script_message "<target>" "<arg1>" "<arg2>" ...``
-    Send a message to the client named ``<target>``, and pass it the following
-    list of arguments. The target can be for example a script (Lua scripts
-    can get their name via ``mp.get_script_name()``). What this message means,
-    how many arguments it takes, and what the arguments mean is fully up to
-    the target and the sender. Lua scripts use it to add key bindings via
-    input.conf.
+``script_message "<arg1>" "<arg2>" ...``
+    Send a message to all clients, and pass it the following list of arguments.
+    What this message means, how many arguments it takes, and what the arguments
+    mean is fully up to the receiver and the sender. Every client receives the
+    message, so be careful about name clashes (or use ``script_message_to``).
+
+``script_message_to "<target>" "<arg1>" "<arg2>" ...``
+    Same as ``script_message``, but send it only to the client named
+    ``<target>``. Each client (scripts etc.) has a unique name. For example,
+    Lua scripts can get their name via ``mp.get_script_name()``.
+
+    (Scripts use this internally to dispatch key bindings, and this can also
+    be used in input.conf to reassign such bindings.)
+
 
 Undocumented commands: ``tv_start_scan``, ``tv_step_channel``, ``tv_step_norm``,
 ``tv_step_chanlist``, ``tv_set_channel``, ``tv_last_channel``, ``tv_set_freq``,
diff --git a/DOCS/man/en/lua.rst b/DOCS/man/en/lua.rst
index c632553c5c..fc7606a5fc 100644
--- a/DOCS/man/en/lua.rst
+++ b/DOCS/man/en/lua.rst
@@ -162,13 +162,13 @@ The ``mp`` module is preloaded, although it can be loaded manually with
 
     The ``name`` argument should be a short symbolic string. It allows the user
     to remap the key binding via input.conf using the ``script_message``
-    command, the script name, and the name of the key binding (see below for
+    command, and the name of the key binding (see below for
     an example). The name should be unique across other bindings in the same
     script - if not, the previous binding with the same name will be
     overwritten. You can omit the name, in which case a random name is generated
     internally.
 
-    Internally, key bindings are dispatched via the ``script_message`` input
+    Internally, key bindings are dispatched via the ``script_message_to`` input
     command and ``mp.register_script_command``.
 
     Trying to map multiple commands to a key will essentially prefer a random
@@ -187,17 +187,24 @@ The ``mp`` module is preloaded, although it can be loaded manually with
 
     This will print the message ``the key was pressed`` when ``x`` was pressed.
 
-    The user can remap these key bindings. Assume the above script was using
-    the filename ``fooscript.lua``, then the user has to put the following
+    The user can remap these key bindings. Then the user has to put the following
     into his input.conf to remap the command to the ``y`` key:
 
     ::
 
-        y script_message lua/fooscript something
+        y script_message something
+
 
     This will print the message when the key ``y`` is pressed. (``x`` will
     still work, unless the user overmaps it.)
 
+    You can also explicitly send a message to a named script only. Assume the
+    above script was using the filename ``fooscript.lua``:
+
+    ::
+
+        y script_message_to lua/fooscript something
+
 ``mp.add_forced_key_binding(...)``
     This works almost the same as ``mp.add_key_binding``, but registers the
     key binding in a way that will overwrite the user's custom bindings in his
@@ -292,8 +299,9 @@ The ``mp`` module is preloaded, although it can be loaded manually with
     The level is a string, see ``msg.log`` for allowed log levels.
 
 ``mp.register_script_command(name, fn)``
-    This is a helper to dispatch ``script_message`` invocations to Lua
-    functions. ``fn`` is called if ``script_message`` is called on this script
+    This is a helper to dispatch ``script_message`` or ``script_message_to``
+    invocations to Lua functions. ``fn`` is called if ``script_message`` or
+    ``script_message_to`` (with this script as destination) is run
     with ``name`` as first parameter. The other parameters are passed to ``fn``.
     If a command with the given name is already registered, it's overwritten.