osc: rework window control configuration to add auto mode

To aid in discoverability, and to address the most common case
directly, I'm adding an 'auto' mode for the window controls. In
this case, we will show the controls if there is no window border
and hide them if there are borders. This also respects the option
being toggled at runtime.

To ensure that it works in the wayland case, I've also made sure
that the wayland code explicitly forces the option to false if
decoration support is missing.

Based on feedback, I've split the config in two, with one option
for whether controls are active, and one for alignment. These are
new enough that we can get away with ignoring compatibility.

DOCS/man/osc.rst

@@ -344,7 +344,7 @@ Configurable Options
     fixed later.
 
 ``windowcontrols``
-    Default: no (Do not show window controls)
+    Default: auto (Show window controls if there is no window border)
 
     Whether to show window management controls over the video, and if so,
     which side of the window to place them. This may be desirable when the
@@ -356,6 +356,12 @@ Configurable Options
     and ``quit``. Not all platforms implement ``minimize`` and ``maximize``,
     but ``quit`` will always work.
 
+``windowcontrols_alignment``
+    Default: right
+
+    If window controls are shown, indicates which side should they be aligned
+    to.
+
     Supports ``left`` and ``right`` which will place the controls on those
     respective sides.
 

player/lua/osc.lua

@@ -45,7 +45,8 @@ local user_opts = {
     visibility = "auto",        -- only used at init to set visibility_mode(...)
     boxmaxchars = 80,           -- title crop threshold for box layout
     boxvideo = false,           -- apply osc_param.video_margins to video
-    windowcontrols = "no",      -- where to show window controls (or not at all)
+    windowcontrols = "auto",    -- whether to show window controls
+    windowcontrols_alignment = "right" -- which side to show window controls on
 }
 
 -- read_options may modify hidetimeout, so save the original default value in
@@ -58,6 +59,21 @@ if user_opts.hidetimeout < 0 then
     msg.warn("hidetimeout cannot be negative. Using " .. user_opts.hidetimeout)
 end
 
+-- validate window control options
+if user_opts.windowcontrols ~= "auto" and
+   user_opts.windowcontrols ~= "yes" and
+   user_opts.windowcontrols ~= "no" then
+    msg.warn("windowcontrols cannot be \"" ..
+             user_opts.windowcontrols .. "\". Ignoring.")
+    user_opts.windowcontrols = "auto"
+end
+if user_opts.windowcontrols_alignment ~= "right" and
+   user_opts.windowcontrols_alignment ~= "left" then
+    msg.warn("windowcontrols_alignment cannot be \"" ..
+             user_opts.windowcontrols_alignment .. "\". Ignoring.")
+    user_opts.windowcontrols_alignment = "right"
+end
+
 local osc_param = { -- calculated by osc_init()
     playresy = 0,                           -- canvas size Y
     playresx = 0,                           -- canvas size X
@@ -117,6 +133,7 @@ local state = {
     showhide_enabled = false,
     dmx_cache = 0,
     using_video_margins = false,
+    border = true,
 }
 
 local window_control_box_width = 80
@@ -393,6 +410,19 @@ function get_track(type)
     return 0
 end
 
+-- WindowControl helpers
+function window_controls_enabled()
+    val = user_opts.windowcontrols
+    if val == "auto" then
+        return not state.border
+    else
+        return val ~= "no"
+    end
+end
+
+function window_controls_alignment()
+    return user_opts.windowcontrols_alignment
+end
 
 --
 -- Element Management
@@ -966,7 +996,7 @@ function add_layout(name)
 end
 
 -- Window Controls
-function window_controls(alignment, topbar)
+function window_controls(topbar)
     local wc_geo = {
         x = 0,
         y = 30 + user_opts.barmargin,
@@ -975,6 +1005,7 @@ function window_controls(alignment, topbar)
         h = 30,
     }
 
+    local alignment = window_controls_alignment()
     local controlbox_w = window_control_box_width
     local titlebox_w = wc_geo.w - controlbox_w
 
@@ -985,12 +1016,6 @@ function window_controls(alignment, topbar)
     if alignment == "left" then
         controlbox_left = wc_geo.x
         titlebox_left = wc_geo.x + controlbox_w + 5
-    elseif alignment == "right" or
-           alignment == "yes" then
-        -- Already default
-    else
-        msg.error("Invalid setting \""..alignment.."\" for windowcontrols")
-        -- Falls back to "right"
     end
 
     add_area("window-controls",
@@ -1367,7 +1392,7 @@ layouts["slimbox"] = function ()
 
 end
 
-function bar_layout(direction, windowcontrols)
+function bar_layout(direction)
     local osc_geo = {
         x = -2,
         y,
@@ -1386,10 +1411,10 @@ function bar_layout(direction, windowcontrols)
     -- Special topbar handling when window controls are present
     local padwc_l
     local padwc_r
-    if direction < 0 or windowcontrols == "no" then
+    if direction < 0 or not window_controls_enabled() then
         padwc_l = 0
         padwc_r = 0
-    elseif windowcontrols == "left" then
+    elseif window_controls_alignment() == "left" then
         padwc_l = window_control_box_width
         padwc_r = 0
     else
@@ -1571,11 +1596,11 @@ function bar_layout(direction, windowcontrols)
 end
 
 layouts["bottombar"] = function()
-    bar_layout(-1, false)
+    bar_layout(-1)
 end
 
 layouts["topbar"] = function()
-    bar_layout(1, user_opts.windowcontrols)
+    bar_layout(1)
 end
 
 -- Validate string type user options
@@ -1992,9 +2017,8 @@ function osc_init()
     layouts[user_opts.layout]()
 
     -- load window controls
-    if user_opts.windowcontrols ~= "no" then
-        window_controls(user_opts.windowcontrols,
-                        user_opts.layout == "topbar")
+    if window_controls_enabled() then
+        window_controls(user_opts.layout == "topbar")
     end
 
     --do something with the elements
@@ -2244,7 +2268,7 @@ function render()
         end
     end
 
-    if user_opts.windowcontrols ~= "no" then
+    if osc_param.areas["window-controls"] then
         for _,cords in ipairs(osc_param.areas["window-controls"]) do
             if state.osc_visible then -- activate only when OSC is actually visible
                 set_virt_mouse_area(cords.x1, cords.y1, cords.x2, cords.y2, "window-controls")
@@ -2470,6 +2494,11 @@ mp.observe_property("fullscreen", "bool",
         request_init()
     end
 )
+mp.observe_property("border", "bool",
+    function(name, val)
+        state.border = val
+    end
+)
 mp.observe_property("idle-active", "bool",
     function(name, val)
         state.idle = val

video/out/wayland_common.c

@@ -1047,8 +1047,12 @@ static int create_xdg_surface(struct vo_wayland_state *wl)
 
 static int set_border_decorations(struct vo_wayland_state *wl, int state)
 {
-    if (!wl->xdg_toplevel_decoration)
+    if (!wl->xdg_toplevel_decoration) {
+        wl->vo_opts->border = false;
+        m_config_cache_write_opt(wl->vo_opts_cache,
+                                 &wl->vo_opts->border);
         return VO_NOTIMPL;
+    }
 
     enum zxdg_toplevel_decoration_v1_mode mode;
     if (state) {
@@ -1131,6 +1135,9 @@ int vo_wayland_init(struct vo *vo)
         wl->xdg_toplevel_decoration = zxdg_decoration_manager_v1_get_toplevel_decoration(wl->xdg_decoration_manager, wl->xdg_toplevel);
         set_border_decorations(wl, wl->vo_opts->border);
     } else {
+        wl->vo_opts->border = false;
+        m_config_cache_write_opt(wl->vo_opts_cache,
+                                 &wl->vo_opts->border);
         MP_VERBOSE(wl, "Compositor doesn't support the %s protocol!\n",
                    zxdg_decoration_manager_v1_interface.name);
     }