eget: simplify User-Agent handling, remove eval and duplication

eget

@@ -309,9 +309,7 @@ verbose=''
 WGETNOSSLCHECK=''
 CURLNOSSLCHECK=''
 AXELNOSSLCHECK=''
-WGETUSERAGENT=''
-CURLUSERAGENT=''
-AXELUSERAGENT=''
+USERAGENT=''
 WGETHEADER=''
 CURLHEADER=''
 AXELHEADER=''
@@ -513,10 +511,7 @@ while [ -n "$1" ] ; do
             USEOUTPUTDIR="$1"
             ;;
         -U|-A|--user-agent)
-            user_agent="Mozilla/5.0 (X11; Linux $arch) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36" #"
-            WGETUSERAGENT="-U '$user_agent'"
-            CURLUSERAGENT="-A '$user_agent'"
-            AXELUSERAGENT="--user-agent='$user_agent'"
+            USERAGENT="Mozilla/5.0 (X11; Linux $arch) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36"
             ;;
         --compressed)
             CURLCOMPRESSED='--compressed'
@@ -1030,11 +1025,8 @@ esac
 # Defined globally so it can be used by aria2/axel backends for header operations
 __wget()
 {
-    if [ -n "$WGETUSERAGENT" ] ; then
-        docmd $WGET $FORCEIPV $WGETQ $WGETSHOWPROGRESS $NOGLOB $WGETCOMPRESSED $WGETHEADER $WGETOUTPUTDIR $WGETNOSSLCHECK $WGETNODIRECTORIES $WGETCONTINUE $WGETTIMEOUT $WGETREADTIMEOUT $WGETRETRYCONNREFUSED $WGETTRIES $WGETLOADCOOKIES $WGETRUSTSERVERNAMES "$(eval echo "$WGETUSERAGENT")" $EGET_WGET_OPTIONS "$@"
-    else
-        docmd $WGET $FORCEIPV $WGETQ $WGETSHOWPROGRESS $NOGLOB $WGETCOMPRESSED $WGETHEADER $WGETOUTPUTDIR $WGETNOSSLCHECK $WGETNODIRECTORIES $WGETCONTINUE $WGETTIMEOUT $WGETREADTIMEOUT $WGETRETRYCONNREFUSED $WGETTRIES $WGETLOADCOOKIES $WGETRUSTSERVERNAMES $EGET_WGET_OPTIONS "$@"
-    fi
+    [ -n "$USERAGENT" ] && set -- -U "$USERAGENT" "$@"
+    docmd $WGET $FORCEIPV $WGETQ $WGETSHOWPROGRESS $NOGLOB $WGETCOMPRESSED $WGETHEADER $WGETOUTPUTDIR $WGETNOSSLCHECK $WGETNODIRECTORIES $WGETCONTINUE $WGETTIMEOUT $WGETREADTIMEOUT $WGETRETRYCONNREFUSED $WGETTRIES $WGETLOADCOOKIES $WGETRUSTSERVERNAMES $EGET_WGET_OPTIONS "$@"
 }
 
 
@@ -1230,11 +1222,8 @@ elif [ "$EGET_BACKEND" = "curl" ] ; then
 
 __curl()
 {
-    if [ -n "$CURLUSERAGENT" ] ; then
-        docmd $CURL $FORCEIPV --fail -L $CURLQ $CURLSHOWPROGRESS $CURLCOMPRESSED $CURLHEADER $CURLOUTPUTDIR $CURLNOSSLCHECK $CURLCONTINUE $CURLMAXTIME $CURLRETRYCONNREFUSED $CURLRETRY $CURLCOOKIE $CURLTRUSTSERVERNAMES "$(eval echo "$CURLUSERAGENT")" $EGET_CURL_OPTIONS "$@"
-    else
-        docmd $CURL $FORCEIPV --fail -L $CURLQ $CURLSHOWPROGRESS $CURLCOMPRESSED $CURLHEADER $CURLOUTPUTDIR $CURLNOSSLCHECK $CURLCONTINUE $CURLMAXTIME $CURLRETRYCONNREFUSED $CURLRETRY $CURLCOOKIE $CURLTRUSTSERVERNAMES $EGET_CURL_OPTIONS "$@"
-    fi
+    [ -n "$USERAGENT" ] && set -- -A "$USERAGENT" "$@"
+    docmd $CURL $FORCEIPV --fail -L $CURLQ $CURLSHOWPROGRESS $CURLCOMPRESSED $CURLHEADER $CURLOUTPUTDIR $CURLNOSSLCHECK $CURLCONTINUE $CURLMAXTIME $CURLRETRYCONNREFUSED $CURLRETRY $CURLCOOKIE $CURLTRUSTSERVERNAMES $EGET_CURL_OPTIONS "$@"
 }
 # put remote content to stdout
 url_scat()
@@ -1352,11 +1341,8 @@ __axel()
     local AXELQ_LOCAL="$AXELQ"
     # --show-progress overrides --quiet for axel
     [ -n "$AXELSHOWPROGRESS" ] && AXELQ_LOCAL=''
-    if [ -n "$AXELUSERAGENT" ] ; then
-        docmd $AXEL $FORCEIPV $AXELQ_LOCAL $AXELOUTPUTDIR $AXELCONTINUE $AXELTIMEOUT $AXELHEADER $AXELNOSSLCHECK "$(eval echo "$AXELUSERAGENT")" $EGET_AXEL_OPTIONS "$@"
-    else
-        docmd $AXEL $FORCEIPV $AXELQ_LOCAL $AXELOUTPUTDIR $AXELCONTINUE $AXELTIMEOUT $AXELHEADER $AXELNOSSLCHECK $EGET_AXEL_OPTIONS "$@"
-    fi
+    [ -n "$USERAGENT" ] && set -- --user-agent="$USERAGENT" "$@"
+    docmd $AXEL $FORCEIPV $AXELQ_LOCAL $AXELOUTPUTDIR $AXELCONTINUE $AXELTIMEOUT $AXELHEADER $AXELNOSSLCHECK $EGET_AXEL_OPTIONS "$@"
 }
 
 # put remote content to stdout