There are too many FTL files for Thunderbird L10n now, so I’m going to try to write Java code to deal with them in MozillaTranslator or its successor. I don’t plan to write a full Java transcodification of Fluent libraries, just the strictly needed code to parsing (including comments and spaces, not just meaningful elements) and writing FTL files.
I plan to use fluent.js as the reference model (I think it is the closer syntax to Java, apart from C#, but I’m hesitant to use a non-official implementation as model). Of all JS Fluent packages, I’d say the one I need is fluent/syntax. Am I right? Will I need something else besides it?