select.lua: populate the context menu

Make select.lua parse menu.conf, fill menu-data and open the context
menu. This is done from select.lua to reuse the code to format the data
and retrieve key bindings.

The first time the context menu is opened, menu-data is filled
initially, and the referenced properties are observed so that menu-data
is already updated by the next time you open the context menu. So if you
never use the context menu there is no extra overhead.

While the context menu is scrollable, for the playlist it is better to
start from around the current entry rather than from the beginning, and
since menu-data has no way to specify where to start, when there are
more than 25 items playlist items this adds … entries that open the
scrollable console menu when clicked.

input-bindings is parsed to show the shortcuts bound to commands. Since
it is not observable, it just uses the bindings from the first time the
context menu is opened. console and stats key bindings are skipped in
case the context menu is opened together with those scripts. Multimedia
and numpad keys are not shown to reduce clutter.

The old Context Menu section of the docs is merged in the more detailed
context_menu.rst to not repeat the same information.

Author: guidocella

.luacheckrc

@@ -106,4 +106,5 @@ stds = { mp = { read_globals = mp_globals } }
 -- mp_internal seems to be merged with mp for other files too...
 files["player/lua/defaults.lua"] = { globals = mp_internal }
 files["player/lua/auto_profiles.lua"] = { globals = { "p", "get" } }
+files["player/lua/select.lua"] = { globals = { "p", "get" } }
 max_line_length = 100

DOCS/man/context_menu.rst

@@ -1,13 +1,14 @@
-CONTEXT MENU SCRIPT
-===================
+CONTEXT MENU
+============
 
 The context menu is a menu that pops up on the video window. By default, it is
 bound to right click.
 
 menu.conf
 ---------
 
-You can define your own menu in ``~~/menu.conf`` (see `FILES`_). It is
+You can define your own menu in ``~~/menu.conf`` (see `FILES`_), or an
+alternative path specified with ``--script-opt=select-menu_conf_path``. It is
 recommended to use the default ``menu.conf`` from
 https://github.com/mpv-player/mpv/blob/master/etc/menu.conf as an example to get
 started.
@@ -30,6 +31,19 @@ submenu with the relative items: ``$playlist``, ``$video-tracks``,
 ``$editions``, ``$audio-devices``. These menus are automatically disabled when
 empty.
 
+To use the native context menu, you need to fill the ``menu-data`` property with
+menu definition data, and call the ``context-menu`` command. In builtin scripts,
+this is done by ``select.lua``, which parses ``menu.conf`` to populate
+``menu-data``. It then calls the ``context-menu`` command on platforms where
+integration with the native context menu is implemented, while on platforms
+where it is not, it opens ``context_menu.lua``.
+
+On platforms without integration with the native context menu,
+``context_menu.lua`` can be disabled entirely using the
+``--load-context-menu=no`` option. On platforms where the integration is
+implemented, it is already disabled by default, and ``--load-context-menu=yes``
+will make ``select.lua`` use it.
+
 Script messages
 ---------------
 

DOCS/man/mpv.rst

@@ -399,16 +399,6 @@ Ctrl+Wheel up/down
     Change video zoom keeping the part of the video hovered by the cursor under
     it.
 
-Context Menu
--------------
-
-Context Menu is a menu that pops up on the video window on user interaction
-(mouse right click, etc.).
-
-To use this feature, you need to fill the ``menu-data`` property with menu
-definition data, and add a keybinding to run the ``context-menu`` command,
-which can be done with a user script.
-
 USAGE
 =====
 

DOCS/man/select.rst

@@ -7,6 +7,8 @@ providing script bindings that gather and format the data to be selected in the
 console and do operations on the selected item. It can be disabled using the
 ``--load-select=no`` option.
 
+This script is also used to populate the context menu.
+
 Key bindings
 ------------
 
@@ -141,6 +143,9 @@ Available script bindings are:
 ``menu``
     Show a menu with miscellaneous entries.
 
+``context-menu``
+    Show the context menu.
+
 Configuration
 -------------
 
@@ -161,3 +166,26 @@ Configurable options
     Default: yes
 
     Whether to show only the last of history entries with the same path.
+
+``menu_conf_path``
+    Default: ~~/menu.conf (see `FILES`_).
+
+    The path from which to read the custom context menu definition (see `CONTEXT
+    MENU`_).
+
+``max_playlist_items``
+    Default: 25
+
+    The maximum number of playlist entries in the context menu.
+
+``use_context_menu_script``
+    Default: auto
+
+    Whether to use the native context menu or ``context_menu.lua``.
+
+    ``auto`` means ``context_menu.lua`` is used with
+    ``--load-context-menu=yes``, and the native context menu is attempted to be
+    used with ``--load-context-menu=no``.
+
+    ``yes`` allows using a fork of ``context_menu.lua`` with
+    ``--load-context-menu=no``.