[mpv] Fix battery detection

mpv/.config/mpv/mpv.conf

@@ -147,8 +147,8 @@ ytdl-raw-options=playlist-reverse=
 [lowquality]
 scale=bilinear
 cscale=ewa_lanczossharp
-video-sync=audio
 interpolation=no
+video-sync=audio
 
 [highquality]
 scale=ewa_lanczossharp
@@ -156,3 +156,6 @@ cscale=ewa_lanczossharp
 video-sync=display-resample
 interpolation=yes
 tscale=oversample
+
+# default to hq
+profile=highquality

mpv/.config/mpv/scripts/battery.lua

@@ -1,17 +1,24 @@
 -- If the laptop is on battery, the profile 'lq' will be loaded; otherwise 'hq' is used
-local lqprofile = "lq"
-local hqprofile = "hq"
-local utils = require 'mp.utils'
-if mp.get_property_bool("option-info/vo/set-from-commandline") == true then
-    return
+--
+local lqprofile = "lowquality"
+local hqprofile = "highquality"
+
+local function powerstate()
+  local f = assert(io.open("/sys/class/power_supply/AC/online"))
+  local t = f:read("*n")
+  f:close()
+  return t
 end
-t = {}
-t.args = {"/bin/cat", "/sys/class/power_supply/AC/online"}
-res = utils.subprocess(t)
-if res.stdout == "0\n" then
-    mp.msg.info("On Battery, setting low-quality options.")
+
+local function adjust()
+  local state = powerstate()
+  -- this actually overrides automatically applied profiles
+  -- like 'protocol.http'
+  if state == 0 then
+    mp.msg.info("Running on battery, setting low-quality options.")
     mp.set_property("profile", lqprofile)
-    mp.set_property("speed", 2)
-else
-    mp.msg.info("On AC, setting high-quality options.")
+  else
+    mp.msg.info("Not running on battery, setting high-quality options.")
+  end
 end
+mp.add_hook("on_load", 1, adjust)