/// CLI entry point for the terminal Wolf3D host.
///
/// This executable locates bundled retail assets, constructs a [WolfEngine]
/// configured for terminal rendering, and then hands control to [CliGameLoop].
library;

import 'dart:io';

import 'package:args/args.dart';
import 'package:wolf_3d_dart/wolf_3d_audio.dart';
import 'package:wolf_3d_dart/wolf_3d_data.dart';
import 'package:wolf_3d_dart/wolf_3d_data_types.dart';
import 'package:wolf_3d_dart/wolf_3d_engine.dart';
import 'package:wolf_3d_dart/wolf_3d_host.dart';
import 'package:wolf_3d_dart/wolf_3d_input.dart';

/// Restores terminal state before exiting the process with [code].
void exitCleanly(int code) {
  stdout.write('\x1b[0m'); // Reset color
  stdout.write('\x1b[2J\x1b[H'); // Clear screen
  stdout.write('\x1b[?25h'); // SHOW the cursor again
  exit(code);
}

/// Launches the CLI renderer using discoverable or user-provided game data.
void main(List<String> arguments) async {
  final argParser = ArgParser()
    ..addOption(
      'data-directory',
      abbr: 'd',
      valueHelp: 'path',
      help: 'Directory containing Wolf3D data files.',
    )
    ..addFlag(
      'help',
      abbr: 'h',
      negatable: false,
      help: 'Show usage information.',
    );

  late final ArgResults parsedArgs;
  try {
    parsedArgs = argParser.parse(arguments);
  } on FormatException catch (e) {
    stderr.writeln(e.message);
    stderr.writeln('Usage: wolf_3d_cli [options]');
    stderr.writeln(argParser.usage);
    exitCleanly(64);
  }

  if (parsedArgs.flag('help')) {
    stdout.writeln('Usage: wolf_3d_cli [options]');
    stdout.writeln(argParser.usage);
    exitCleanly(0);
  }

  final String? rawPath = parsedArgs.option('data-directory');
  final String? dataDirectory = rawPath != null && rawPath.trim().isNotEmpty
      ? rawPath.trim()
      : null;

  if (dataDirectory != null) {
    stdout.write('Discovering game data in "$dataDirectory"...');
  } else {
    stdout.write('Discovering game data...');
  }

  final availableGames = await WolfensteinLoader.discover(
    directoryPath: dataDirectory,
    recursive: true,
  );

  if (availableGames.isEmpty) {
    if (dataDirectory == null) {
      stderr.writeln('\nNo Wolf3D game data was discovered.');
      stderr.writeln('Provide a game-data directory with one of these flags:');
      stderr.writeln('  --data-directory <path>');
      stderr.writeln('  -d <path>');
    } else {
      stderr.writeln('\nNo Wolf3D game files were found at: $dataDirectory');
      stderr.writeln(
        'Please provide valid game data files before starting the CLI host.',
      );
    }
    exitCleanly(1);
  }

  CliGameLoop? gameLoop;
  late final WolfEngine engine;

  void stopAndExit(int code) {
    gameLoop?.stop();
    engine.audio.dispose();
    exitCleanly(code);
  }

  engine = WolfEngine(
    availableGames: availableGames.values.toList(growable: false),
    startingEpisode: 0,
    frameBuffer: FrameBuffer(
      stdout.terminalColumns,
      stdout.terminalLines,
    ),
    input: CliInput(),
    engineAudio: NativeSubprocessAudio(),
    onGameWon: () => stopAndExit(0),
    onQuit: () => stopAndExit(0),
    saveGamePersistence: DefaultSaveGamePersistence(),
  );

  await engine.audio.init();
  engine.init();

  final persistence = DefaultRendererSettingsPersistence(
    hostKey: rendererSettingsHostCli,
  );
  final WolfRendererSettings? saved = await persistence.load();

  gameLoop = CliGameLoop(
    engine: engine,
    onExit: stopAndExit,
    persistence: persistence,
    initialSettings: saved,
  );

  await gameLoop.start();
}