'use strict';

var isWin = process.platform === 'win32';

function notFoundError(command, syscall) {
    var err;

    err = new Error(syscall + ' ' + command + ' ENOENT');
    err.code = err.errno = 'ENOENT';
    err.syscall = syscall + ' ' + command;

    return err;
}

function hookChildProcess(cp, parsed) {
    var originalEmit;

    if (!isWin) {
        return;
    }

    originalEmit = cp.emit;
    cp.emit = function (name, arg1) {
        var err;

        // If emitting "exit" event and exit code is 1, we need to check if
        // the command exists and emit an "error" instead
        // See: https://github.com/IndigoUnited/node-cross-spawn/issues/16
        if (name === 'exit') {
            err = verifyENOENT(arg1, parsed, 'spawn');

            if (err) {
                return originalEmit.call(cp, 'error', err);
            }
        }

        return originalEmit.apply(cp, arguments);
    };
}

function verifyENOENT(status, parsed, syscall) {
    if (isWin && status === 1 && !parsed.file) {
        return notFoundError(parsed.original, syscall);
    }

    return null;
}

module.exports.hookChildProcess = hookChildProcess;
module.exports.verifyENOENT     = verifyENOENT;
module.exports.notFoundError    = notFoundError;