package lib;

import kernel.ps.Process;
import kernel.ps.ProcessHandle;

using tink.CoreApi;

abstract class CLIAppBase implements Process {
	private var handle: ProcessHandle;

	private final _subcommandsSync: Map<String, (Array<String>) -> Bool> = [];
	private final _subcommandsAsync: Map<String, (Array<String>) -> Future<Bool>> = [];
	private final _subcommandsSynopsis: Array<String> = [];

	public function run(handle: ProcessHandle){
		this.handle = handle;

		var subcommand = handle.args[0];

		if (subcommand == null || subcommand == "") {
			handle.writeLine("No subcommand specified");
			printHelp();
			return handle.close(false);
		}

		var args = handle.args.slice(1);

		if (_subcommandsSync.exists(subcommand)) {
			var result = _subcommandsSync[subcommand](args);
			return handle.close(result);
		} else if (_subcommandsAsync.exists(subcommand)) {
			_subcommandsAsync[subcommand](args).handle(handle.close);
		} else {
			handle.writeLine("Unknown subcommand: " + subcommand);
			printHelp();
			return handle.close(false);
		}

	}

	private function registerSyncSubcommand(command: String, callback: (Array<String>) -> Bool, synopsis: String = null) {
		_subcommandsSync.set(command, callback);
		_subcommandsSynopsis.push(command + " " + synopsis);
	}

	private function registerAsyncSubcommand(command: String, callback: (Array<String>) -> Future<Bool>, synopsis: String = null) {
		_subcommandsAsync.set(command, callback);
		_subcommandsSynopsis.push(command + " " + synopsis);
	}

	private function printHelp() {
		handle.writeLine("Usage: <subcommand> [args]");
		handle.writeLine("Subcommands:");
		for (subcommand in _subcommandsSynopsis) {
			handle.writeLine("  " + subcommand);
		}
	}
}