stats.lua: add page 4: active key-bindings list

This is a scrollable page which also works nicely with the terminal
OSD. Typically there are more than 100 bound keys.

It groups the binding using fuzzy property/command/script name after
simple analysis of the command string, and then further sorts the
binding in each group according to the "complexity" of the key itself
(plain keys -> keys with modifiers, alphabetically, etc).

The alignment/grouping style is heavily inspired by @medhefgo's #8924
but otherwise it's an independent implementation.

1 files changed, 17 insertions, 0 deletions

diff --git a/DOCS/man/stats.rst b/DOCS/man/stats.rst
index f9c125447c..3684922189 100644
--- a/DOCS/man/stats.rst
+++ b/DOCS/man/stats.rst
@@ -24,6 +24,7 @@ stats:
 1      Show usual stats
 2      Show frame timings (scroll)
 3      Input cache stats
+4      Active key bindings (scroll)
 0      Internal stuff (scroll)
 ====   ==================
 
@@ -64,6 +65,8 @@ Configurable Options
     Default: 2
 ``key_page_3``
     Default: 3
+``key_page_4``
+    Default: 4
 ``key_page_0``
     Default: 0
 
@@ -183,6 +186,20 @@ Using ``input.conf``, it is also possible to directly display a certain page::
     i script-binding stats/display-page-1
     e script-binding stats/display-page-2
 
+Active key bindings page
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Lists the active key bindings and the commands they're bound to, excluding the
+interactive keys of the stats script itself. See also `--input-test`_ for more
+detailed view of each binding.
+
+The keys are grouped automatically using a simple analysis of the command
+string, and one should not expect documentation-level grouping accuracy,
+however, it should still be reasonably useful.
+
+Like with ``--input-test``, the list includes bindings from ``input.conf`` and
+from user scripts. Use `--no-config`` to list only built-in bindings.
+
 Internal stuff page
 ~~~~~~~~~~~~~~~~~~~