fix(scripts/build): fix date formatting issue on different OS

Signed-off-by: njucjc <[email protected]>

Author: njucjc

scripts/build/.variables

@@ -13,13 +13,23 @@ PLATFORM=${PLATFORM:-}
 VERSION=${VERSION:-$(git describe --match 'v[0-9]*' --dirty='.m' --always --tags | sed 's/^v//' 2>/dev/null || echo "unknown-version" )}
 GITCOMMIT=${GITCOMMIT:-$(git rev-parse --short HEAD 2> /dev/null || true)}
 
-if [ "$(uname)" = "Darwin" ]; then
-    # Using BSD date (macOS), which doesn't suppoort the --date option
-    # date -jf "<input format>" "<input value>" +"<output format>" (https://unix.stackexchange.com/a/86510)
-    BUILDTIME=${BUILDTIME:-$(TZ=UTC date -jf "%s" "${SOURCE_DATE_EPOCH:-$(date +%s)}" +"%Y-%m-%dT%H:%M:%SZ")}
-else
-    # Using GNU date (Linux)
-    BUILDTIME=${BUILDTIME:-$(TZ=UTC date -u --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +"%Y-%m-%dT%H:%M:%SZ")}
+# Try GNU date syntax first (Linux), fallback to BSD date syntax (macOS) if failed
+BUILDTIME_SET=false
+if [ -z "${BUILDTIME:-}" ]; then
+    # Try GNU date syntax
+    TZ=UTC date -u --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +"%Y-%m-%dT%H:%M:%SZ" >/dev/null 2>&1 && {
+        BUILDTIME=$(TZ=UTC date -u --date="@${SOURCE_DATE_EPOCH:-$(date +%s)}" +"%Y-%m-%dT%H:%M:%SZ")
+        BUILDTIME_SET=true
+    }
+fi
+
+if [ -z "${BUILDTIME:-}" ] && [ "$BUILDTIME_SET" = false ]; then
+    # Fallback to BSD date syntax
+    echo "GNU date syntax not supported, fallback to BSD date syntax"
+    TZ=UTC date -jf "%s" "${SOURCE_DATE_EPOCH:-$(date +%s)}" +"%Y-%m-%dT%H:%M:%SZ" >/dev/null 2>&1 && {
+        BUILDTIME=$(TZ=UTC date -jf "%s" "${SOURCE_DATE_EPOCH:-$(date +%s)}" +"%Y-%m-%dT%H:%M:%SZ")
+        BUILDTIME_SET=true
+    }
 fi
 
 case "$VERSION" in