fix(scripts/renew_copyright_header): Add per filetype handling

Otherwise, the mistakes are not avoidable.

scripts/renew_copyright_header.sh

@@ -1,6 +1,42 @@
 #! /usr/bin/env sh
 
-fd --type file . | xargs grep 'The Trinitrix Project <soispha@vhack.eu, antifallobst@systemausfall.org>' | awk 'BEGIN{ FS=":"} {print $1}' | xargs sed -i '20s|*/||; 1,19d'
+TEMPLATE_LINE_LENGHT=19
+
+fd --type file . | while read -r file; do
+    if grep --quiet 'The Trinitrix Project <soispha@vhack.eu, antifallobst@systemausfall.org>' "$file"; then
+        filename="$(basename -- "$file")"
+        extension="${filename##*.}"
+        filename="${filename%.*}"
+
+        # We need to differentiate, when removing the old copyright header, as some
+        # formatters do weird things to the file
+        case "$extension" in
+        # normal '#' comments (these are 19 lines long)
+        "Makefile" | "toml")
+            sed --in-place "1,${TEMPLATE_LINE_LENGHT}d" "$file"
+            ;;
+        # normal '/* ... */' like comments (these are 21 lines long--'#' + 2)
+        "c" | "ebnf" | "h" | "md" | "rs" | "tri")
+            lenght="$((TEMPLATE_LINE_LENGHT + 2))"
+            sed --in-place "1,${lenght}d;" "$file"
+            ;;
+        # alejandra (the nix formatter) removes the blank line after the comment,
+        # thus only 18 lines
+        "nix")
+            lenght="$((TEMPLATE_LINE_LENGHT - 1))"
+            sed --in-place "1,${lenght}d;" "$file"
+            ;;
+        # Shell needs a shebang on the first line, only after the first line can we
+        # remove the 19 lines
+        "sh")
+            sed --in-place "2,${TEMPLATE_LINE_LENGHT}d;" "$file"
+            ;;
+        *)
+            echo "File '$file' with extension '$extension' is not know yet, please add it!"
+            ;;
+        esac
+    fi
+done
 
 nix fmt