Improve compatibility with some pango parsers by always escaping complex chars

qbar/src/QBar/BlockOutput.hs

@@ -45,6 +45,7 @@ import QBar.Prelude
 
 import Control.Lens
 import Data.Aeson
+import Data.Char
 import Data.Int (Int64)
 import Data.Text.Lazy qualified as T
 import GHC.Generics
@@ -209,8 +210,31 @@ printedLength (BlockText b) = sum . map segmentLength $ b
 mkText :: Bool -> Importance -> T.Text -> BlockText
 mkText active importance segmentText = BlockText [BlockTextSegment { segmentText = pangoFriendly segmentText, active, importance }]
   where
+    toHex :: Int -> T.Text
+    toHex 1 = "1"
+    toHex 2 = "2"
+    toHex 3 = "3"
+    toHex 4 = "4"
+    toHex 5 = "5"
+    toHex 6 = "6"
+    toHex 7 = "7"
+    toHex 8 = "8"
+    toHex 9 = "9"
+    toHex 10 = "A"
+    toHex 11 = "B"
+    toHex 12 = "C"
+    toHex 13 = "D"
+    toHex 14 = "E"
+    toHex 15 = "F"
+    toHex x
+      | x <= 0 = "0"
+      | otherwise = toHex (div x 16) <> toHex (mod x 16)
+    pangoFriendlyIcon :: Char -> T.Text
+    pangoFriendlyIcon x
+      | isAlphaNum x || isAscii x = T.singleton x
+      | otherwise = "&#x" <> toHex (ord x) <> ";"
     pangoFriendly :: T.Text -> T.Text
-    pangoFriendly = T.replace "<" "&lt;" . T.replace ">" "&gt;" . T.replace "&" "&amp;"
+    pangoFriendly = T.concatMap pangoFriendlyIcon . T.replace "<" "&lt;" . T.replace ">" "&gt;" . T.replace "&" "&amp;"
 
 activeImportantText :: Importance -> T.Text -> BlockText
 activeImportantText = mkText True