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"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.StdioClientTransport = exports.DEFAULT_INHERITED_ENV_VARS = void 0;
exports.getDefaultEnvironment = getDefaultEnvironment;
const cross_spawn_1 = __importDefault(require("cross-spawn"));
const node_process_1 = __importDefault(require("node:process"));
const node_stream_1 = require("node:stream");
const stdio_js_1 = require("../shared/stdio.js");
/**

 * Environment variables to inherit by default, if an environment is not explicitly given.

 */
exports.DEFAULT_INHERITED_ENV_VARS = node_process_1.default.platform === 'win32'
    ? [
        'APPDATA',
        'HOMEDRIVE',
        'HOMEPATH',
        'LOCALAPPDATA',
        'PATH',
        'PROCESSOR_ARCHITECTURE',
        'SYSTEMDRIVE',
        'SYSTEMROOT',
        'TEMP',
        'USERNAME',
        'USERPROFILE',
        'PROGRAMFILES'
    ]
    : /* list inspired by the default env inheritance of sudo */
        ['HOME', 'LOGNAME', 'PATH', 'SHELL', 'TERM', 'USER'];
/**

 * Returns a default environment object including only environment variables deemed safe to inherit.

 */
function getDefaultEnvironment() {
    const env = {};
    for (const key of exports.DEFAULT_INHERITED_ENV_VARS) {
        const value = node_process_1.default.env[key];
        if (value === undefined) {
            continue;
        }
        if (value.startsWith('()')) {
            // Skip functions, which are a security risk.
            continue;
        }
        env[key] = value;
    }
    return env;
}
/**

 * Client transport for stdio: this will connect to a server by spawning a process and communicating with it over stdin/stdout.

 *

 * This transport is only available in Node.js environments.

 */
class StdioClientTransport {
    constructor(server) {
        this._readBuffer = new stdio_js_1.ReadBuffer();
        this._stderrStream = null;
        this._serverParams = server;
        if (server.stderr === 'pipe' || server.stderr === 'overlapped') {
            this._stderrStream = new node_stream_1.PassThrough();
        }
    }
    /**

     * Starts the server process and prepares to communicate with it.

     */
    async start() {
        if (this._process) {
            throw new Error('StdioClientTransport already started! If using Client class, note that connect() calls start() automatically.');
        }
        return new Promise((resolve, reject) => {
            this._process = (0, cross_spawn_1.default)(this._serverParams.command, this._serverParams.args ?? [], {
                // merge default env with server env because mcp server needs some env vars
                env: {
                    ...getDefaultEnvironment(),
                    ...this._serverParams.env
                },
                stdio: ['pipe', 'pipe', this._serverParams.stderr ?? 'inherit'],
                shell: false,
                windowsHide: node_process_1.default.platform === 'win32',
                cwd: this._serverParams.cwd
            });
            this._process.on('error', error => {
                reject(error);
                this.onerror?.(error);
            });
            this._process.on('spawn', () => {
                resolve();
            });
            this._process.on('close', _code => {
                this._process = undefined;
                this.onclose?.();
            });
            this._process.stdin?.on('error', error => {
                this.onerror?.(error);
            });
            this._process.stdout?.on('data', chunk => {
                this._readBuffer.append(chunk);
                this.processReadBuffer();
            });
            this._process.stdout?.on('error', error => {
                this.onerror?.(error);
            });
            if (this._stderrStream && this._process.stderr) {
                this._process.stderr.pipe(this._stderrStream);
            }
        });
    }
    /**

     * The stderr stream of the child process, if `StdioServerParameters.stderr` was set to "pipe" or "overlapped".

     *

     * If stderr piping was requested, a PassThrough stream is returned _immediately_, allowing callers to

     * attach listeners before the start method is invoked. This prevents loss of any early

     * error output emitted by the child process.

     */
    get stderr() {
        if (this._stderrStream) {
            return this._stderrStream;
        }
        return this._process?.stderr ?? null;
    }
    /**

     * The child process pid spawned by this transport.

     *

     * This is only available after the transport has been started.

     */
    get pid() {
        return this._process?.pid ?? null;
    }
    processReadBuffer() {
        while (true) {
            try {
                const message = this._readBuffer.readMessage();
                if (message === null) {
                    break;
                }
                this.onmessage?.(message);
            }
            catch (error) {
                this.onerror?.(error);
            }
        }
    }
    async close() {
        if (this._process) {
            const processToClose = this._process;
            this._process = undefined;
            const closePromise = new Promise(resolve => {
                processToClose.once('close', () => {
                    resolve();
                });
            });
            try {
                processToClose.stdin?.end();
            }
            catch {
                // ignore
            }
            await Promise.race([closePromise, new Promise(resolve => setTimeout(resolve, 2000).unref())]);
            if (processToClose.exitCode === null) {
                try {
                    processToClose.kill('SIGTERM');
                }
                catch {
                    // ignore
                }
                await Promise.race([closePromise, new Promise(resolve => setTimeout(resolve, 2000).unref())]);
            }
            if (processToClose.exitCode === null) {
                try {
                    processToClose.kill('SIGKILL');
                }
                catch {
                    // ignore
                }
            }
        }
        this._readBuffer.clear();
    }
    send(message) {
        return new Promise(resolve => {
            if (!this._process?.stdin) {
                throw new Error('Not connected');
            }
            const json = (0, stdio_js_1.serializeMessage)(message);
            if (this._process.stdin.write(json)) {
                resolve();
            }
            else {
                this._process.stdin.once('drain', resolve);
            }
        });
    }
}
exports.StdioClientTransport = StdioClientTransport;
//# sourceMappingURL=stdio.js.map