ferdium: add custom update script

Based on the Lidarr script:
952869b980/pkgs/servers/lidarr/update.sh

pkgs/applications/networking/instant-messengers/ferdium/default.nix

@@ -21,9 +21,7 @@ in mkFranzDerivation rec {
   extraBuildInputs = [ xorg.libxshmfence ];
 
   passthru = {
-    updateScript = nix-update-script {
-      extraArgs = [ "--override-filename" ./default.nix ];
-    };
+    updateScript = ./update.sh;
   };
 
   meta = with lib; {

pkgs/applications/networking/instant-messengers/ferdium/update.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p curl gnused nix-prefetch jq
+
+set -e
+
+dirname="$(dirname "$0")"
+
+updateHash()
+{
+    version=$1
+    arch=$2
+
+    hashKey="${arch}-linux_hash"
+
+    url="https://github.com/ferdium/ferdium-app/releases/download/v$version/Ferdium-linux-$version-$arch.deb"
+    hash=$(nix-prefetch-url --type sha256 $url)
+    sriHash="$(nix hash to-sri --type sha256 $hash)"
+
+    sed -i "s|$hashKey = \"[a-zA-Z0-9\/+-=]*\";|$hashKey = \"$sriHash\";|g" "$dirname/default.nix"
+}
+
+updateVersion()
+{
+    sed -i "s/version = \"[0-9.]*\";/version = \"$1\";/g" "$dirname/default.nix"
+}
+
+currentVersion=$(cd $dirname && nix eval --raw -f ../../../../.. ferdium.version)
+
+latestTag=$(curl https://api.github.com/repos/ferdium/ferdium-app/releases/latest | jq -r ".tag_name")
+latestVersion="$(expr $latestTag : 'v\(.*\)')"
+
+if [[ "$currentVersion" == "$latestVersion" ]]; then
+    echo "Ferdium is up-to-date: ${currentVersion}"
+    exit 0
+fi
+
+updateVersion $latestVersion
+
+updateHash $latestVersion amd64
+updateHash $latestVersion arm64