// Assets/ChessEngines/fairy-chess-server/engine-path.js
import path from 'path';
import os from 'os';
import { fileURLToPath } from 'url';
import { dirname } from 'path';

// Get current file's directory in ES modules
const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);

function getEnginePath() {
    // First check if path is provided through environment variable
    if (process.env.FAIRY_STOCKFISH_PATH) {
        return process.env.FAIRY_STOCKFISH_PATH;
    }

    // Get the current directory (fairy-chess-server)
    const currentDir = __dirname;
    
    // Navigate up to Assets/ChessEngines
    const engineBaseDir = path.join(currentDir, '..', '..');
    // console.log(engineBaseDir + '/Fairy-Stockfish' + '/src' + '/stockfish')
    
    // Determine OS and set appropriate path
    if (os.platform() === 'win32') {
        // Windows path
        return engineBaseDir + '/ChessEngines' + '/stockfish' + '/stockfish.exe'
    } else {
        //res://Assets/ChessEngines/Fairy-Stockfish/src/stockfish
        // Unix-like systems (Linux, macOS)
        return engineBaseDir + '/ChessEngines'+ '/Fairy-Stockfish' + '/src' + '/stockfish';
    }
}

// Verify engine path exists
async function verifyEnginePath(enginePath) {
    const fs = await import('fs');
    if (!fs.existsSync(enginePath)) {
        throw new Error(`Chess engine not found at path: ${enginePath}`);
    }
    return enginePath;
}

export { getEnginePath, verifyEnginePath };