Refactor get-prebuilts for easier addition of apps

Signed-off-by: Velsoth <velsoth@adhoc.zone>

get-prebuilts

@@ -2,10 +2,38 @@
 set -e
 
 BASEDIR=$( dirname $0 )
+PREBUILT_PATH="$BASEDIR/prebuilt/common/apps"
+REPO_URL_FDROID="https://f-droid.org/repo"
+REPO_URL_GUARDIAN="https://guardianproject.info/fdroid/repo"
 
-mkdir -p $BASEDIR/prebuilt/common/apps/
+mkdir -p $PREBUILT_PATH
 
-# F-Droid
-curl -L -o $BASEDIR/prebuilt/common/apps/FDroid.apk -O -L https://f-droid.org/FDroid.apk
-curl -L -o $BASEDIR/prebuilt/common/apps/FDroid.apk.asc -O -L https://f-droid.org/FDroid.apk.asc
-gpg --armor --verify $BASEDIR/prebuilt/common/apps/FDroid.apk.asc $BASEDIR/prebuilt/common/apps/FDroid.apk
+function getPrebuild() {
+  repo="$1"
+  name="$2"
+  full_name="$3"
+  version="$4"
+  version_string=""
+  if [[ ! -z $version ]]; then version_string="_$version"; fi
+  case "$repo" in
+    "guardian") repo_url=$REPO_URL_GUARDIAN ;;
+    * )         repo_url=$REPO_URL_FDROID ;;
+  esac
+  local_app_path="$PREBUILT_PATH/$name.apk"
+  remote_app_path="$repo_url/${full_name}${version_string}.apk"
+  echo -e "Downloading app $name"
+  curl -s \
+    -L -o "$local_app_path" \
+    -O -L "$remote_app_path"
+  curl -s \
+    -L -o "$local_app_path.asc" \
+    -O -L "$remote_app_path.asc"
+  echo -e "Verifying app $name"
+  gpg -q \
+    --armor \
+    --verify \
+    "$local_app_path.asc" \
+    "$local_app_path"
+}
+
+getPrebuild fdroid   FDroid            org.fdroid.fdroid                    1007051