/**
 * Production Server Wrapper
 *
 * Wraps @sveltejs/adapter-node's output with WebSocket support for:
 * - Terminal connections (xterm.js ↔ Docker exec/attach)
 * - Hawser Edge agent connections
 *
 * Usage: node ./server.js
 */

import { createServer as createHttpServer, request as httpRequest } from 'node:http';
import { createServer as createHttpsServer, request as httpsRequest } from 'node:https';
import { createConnection } from 'node:net';
import { connect as tlsConnect, rootCertificates } from 'node:tls';
import { randomUUID, X509Certificate } from 'node:crypto';
import { readFileSync } from 'node:fs';
import { WebSocketServer } from 'ws';
import { handler } from './build/handler.js';

// Patch console to prepend an ISO timestamp and a log level (#1166), e.g.
//   2026-06-11T12:34:56.789Z INFO  ...
//   2026-06-11T12:34:56.789Z WARN  ...
//   2026-06-11T12:34:56.789Z ERROR ...
const _log = console.log;
const _error = console.error;
const _warn = console.warn;
const _info = console.info;
const ts = () => new Date().toISOString();
console.log = (...args) => _log(ts(), 'INFO ', ...args);
console.info = (...args) => _info(ts(), 'INFO ', ...args);
console.warn = (...args) => _warn(ts(), 'WARN ', ...args);
console.error = (...args) => _error(ts(), 'ERROR', ...args);

const PORT = parseInt(process.env.PORT || '3000', 10);
const HOST = process.env.HOST || '0.0.0.0';

// Optional native HTTPS listener (#1102). Off by default to keep existing
// deployments unchanged. When HTTPS_MODE=on, HTTPS_CERT_PATH and
// HTTPS_KEY_PATH must both point to readable PEM files.
const HTTPS_MODE = (process.env.HTTPS_MODE || 'off').toLowerCase();
const useHttps = HTTPS_MODE === 'on';

let server;
if (useHttps) {
	const certPath = process.env.HTTPS_CERT_PATH;
	const keyPath = process.env.HTTPS_KEY_PATH;
	const caPath = process.env.HTTPS_CA_PATH;

	console.log('[HTTPS] mode=on');
	console.log(`[HTTPS] cert=${certPath || '(missing)'}`);
	console.log(`[HTTPS] key=${keyPath || '(missing)'}`);
	console.log(`[HTTPS] ca=${caPath || '(none)'}`);

	if (!certPath || !keyPath) {
		console.error('[HTTPS] HTTPS_MODE=on requires HTTPS_CERT_PATH and HTTPS_KEY_PATH');
		process.exit(1);
	}

	let certPem, keyPem, caPem;
	try {
		certPem = readFileSync(certPath);
		keyPem = readFileSync(keyPath);
		if (caPath) caPem = readFileSync(caPath);
	} catch (e) {
		console.error(`[HTTPS] Failed to read cert/key file: ${e.message}`);
		process.exit(1);
	}

	// Parse cert metadata so operators can confirm they mounted the right file.
	try {
		const x509 = new X509Certificate(certPem);
		console.log(`[HTTPS] cert subject: ${x509.subject.replace(/\n/g, ', ')}`);
		console.log(`[HTTPS] cert issuer:  ${x509.issuer.replace(/\n/g, ', ')}`);
		console.log(`[HTTPS] cert SAN:     ${x509.subjectAltName || '(none)'}`);
		console.log(`[HTTPS] cert valid:   ${x509.validFrom} → ${x509.validTo}`);
		const expiresAt = new Date(x509.validTo).getTime();
		const daysLeft = Math.floor((expiresAt - Date.now()) / 86400000);
		if (daysLeft < 0) {
			console.warn(`[HTTPS] WARNING: certificate expired ${-daysLeft} day(s) ago`);
		} else if (daysLeft < 30) {
			console.warn(`[HTTPS] WARNING: certificate expires in ${daysLeft} day(s)`);
		} else {
			console.log(`[HTTPS] cert expires in ${daysLeft} day(s)`);
		}
	} catch (e) {
		console.error(`[HTTPS] Failed to parse certificate: ${e.message}`);
		process.exit(1);
	}

	const tlsOptions = { cert: certPem, key: keyPem };
	if (caPem) tlsOptions.ca = caPem;

	// HSTS — only meaningful over HTTPS, so wired only here. Default 1 year;
	// set HSTS_MAX_AGE=0 to disable.
	const hstsMaxAge = parseInt(process.env.HSTS_MAX_AGE ?? '31536000', 10);
	const hstsHeader = hstsMaxAge > 0 ? `max-age=${hstsMaxAge}` : null;
	if (hstsHeader) {
		console.log(`[HTTPS] HSTS enabled: ${hstsHeader}`);
	} else {
		console.log('[HTTPS] HSTS disabled (HSTS_MAX_AGE=0)');
	}

	server = createHttpsServer(tlsOptions, (req, res) => {
		if (hstsHeader) res.setHeader('Strict-Transport-Security', hstsHeader);
		handler(req, res);
	});
} else {
	console.log(`[HTTPS] mode=off (set HTTPS_MODE=on to enable native TLS)`);
	server = createHttpServer((req, res) => {
		handler(req, res);
	});
}

// Create WebSocket server attached to the HTTP server
const wss = new WebSocketServer({ noServer: true });

// Track connections
const wsConnections = new Map();
let wsConnectionCounter = 0;

// Track Edge exec sessions: execId -> { ws, environmentId }
const edgeExecSessions = new Map();

// Register global send function for Hawser Edge WebSocket messages.
// hawser.ts checks this first, and handleEdgeExec uses it for terminal relay.
// Reads from __hawserEdgeConnections which is populated by hawser.ts.
globalThis.__hawserSendMessage = (envId, message) => {
	const connections = globalThis.__hawserEdgeConnections;
	if (!connections) return false;
	const conn = connections.get(envId);
	if (!conn || !conn.ws) return false;
	try {
		conn.ws.send(message);
		return true;
	} catch (e) {
		console.error('[Hawser WS] sendMessage error:', e);
		return false;
	}
};

// Register global handler for exec messages from Hawser Edge agents
// Called by hawser.ts when it receives exec_ready/exec_output/exec_end/error messages
globalThis.__terminalHandleExecMessage = (msg) => {
	const execId = msg.execId || msg.requestId;
	if (!execId) return;

	const session = edgeExecSessions.get(execId);
	if (!session || session.ws.readyState !== 1) return;

	if (msg.type === 'exec_ready') {
		// Agent is ready, frontend is already waiting for output
		return;
	}

	if (msg.type === 'exec_output') {
		const bytes = Buffer.from(msg.data, 'base64');
		// Attach sessions carry a stream state: demultiplex non-TTY frames before
		// forwarding. Exec sessions are raw TTY text and pass straight through.
		if (session.streamState) {
			for (const text of processDockerStreamChunk(bytes, session.streamState)) {
				if (text) session.ws.send(JSON.stringify({ type: 'output', data: text }));
			}
		} else {
			session.ws.send(JSON.stringify({ type: 'output', data: bytes.toString('utf-8') }));
		}
		return;
	}

	if (msg.type === 'exec_end') {
		session.ws.send(JSON.stringify({ type: 'exit' }));
		session.ws.close();
		edgeExecSessions.delete(execId);
		return;
	}

	if (msg.type === 'error') {
		session.ws.send(JSON.stringify({ type: 'error', message: msg.error || msg.message }));
		session.ws.close();
		edgeExecSessions.delete(execId);
	}
};

// Handle WebSocket upgrade
server.on('upgrade', async (req, socket, head) => {
	const url = new URL(req.url || '/', `http://${req.headers.host}`);

	// Only handle our specific WebSocket paths
	const isTerminal = url.pathname.includes('/api/containers/') && url.pathname.includes('/exec');
	const isHawser = url.pathname === '/api/hawser/connect';

	if (!isTerminal && !isHawser) {
		socket.destroy();
		return;
	}

	let wsAuth = null;
	if (isTerminal) {
		try {
			if (typeof globalThis.__authenticateWsUpgrade !== 'function') {
				socket.write('HTTP/1.1 503 Service Unavailable\r\nConnection: close\r\n\r\n');
				socket.destroy();
				return;
			}
			wsAuth = await globalThis.__authenticateWsUpgrade(req.headers);
			if (!wsAuth) {
				socket.write('HTTP/1.1 401 Unauthorized\r\nConnection: close\r\n\r\n');
				socket.destroy();
				return;
			}
		} catch (err) {
			console.error('[WS] auth error during upgrade:', err);
			socket.write('HTTP/1.1 500 Internal Server Error\r\nConnection: close\r\n\r\n');
			socket.destroy();
			return;
		}
	}

	wss.handleUpgrade(req, socket, head, (ws) => {
		if (wsAuth) ws.__auth = wsAuth;
		wss.emit('connection', ws, req);
	});
});

wss.on('connection', (ws, req) => {
	const url = new URL(req.url || '/', `http://${req.headers.host}`);
	const connId = `ws-${++wsConnectionCounter}`;
	const remoteIp = (req.headers['x-forwarded-for'] || '').split(',')[0].trim()
		|| req.socket.remoteAddress
		|| 'unknown';

	if (url.pathname === '/api/hawser/connect') {
		handleHawserConnection(ws, connId, remoteIp);
	} else {
		handleTerminalConnection(ws, url, connId);
	}
});

/**
 * Handle terminal exec WebSocket connections.
 * Supports all connection types: socket, direct TCP/TLS, hawser-standard, hawser-edge.
 *
 * Uses globalThis functions exposed by the SvelteKit app (docker.ts):
 * - __terminalGetTarget(envId) - resolves connection info from environment
 * - __terminalCreateExec(containerId, shell, user, envId) - creates exec via Docker API
 * - __terminalResizeExec(execId, cols, rows, envId) - resizes exec terminal
 * - __terminalGetContainerTty(containerId, envId) - reads the container TTY setting
 * - __terminalResizeContainer(containerId, cols, rows, envId) - resizes an attached TTY
 */

// NOTE: createDockerStreamState/decodeChunkedDockerBody/processDockerStreamChunk below
// mirror src/lib/server/docker-stream-core.ts (the tested source of truth). server.js
// runs against ./build and cannot import the TS core at runtime, so the logic is kept
// inline here; keep the two in sync (vite.config.ts imports the core directly).
function buildDockerStreamRequest(path, target, body = '') {
	const host = target.host || 'localhost';
	const tokenHeader = target.hawserToken ? `X-Hawser-Token: ${target.hawserToken}\r\n` : '';
	return (
		`POST ${path} HTTP/1.1\r\n` +
		`Host: ${host}\r\n` +
		`Content-Type: application/json\r\n` +
		`${tokenHeader}` +
		`Connection: Upgrade\r\n` +
		`Upgrade: tcp\r\n` +
		`Content-Length: ${Buffer.byteLength(body)}\r\n` +
		`\r\n` +
		body
	);
}

// Mirrors translateAttachInput in docker-stream-core.ts: for non-TTY attach map a lone
// \r (xterm Enter) to \n (no pty to do it); exec / TTY attach pass through. Keep in sync.
function translateAttachInput(data, nonTtyAttach) {
	if (!nonTtyAttach) return data;
	return data.replace(/\r(?!\n)/g, '\n');
}

function createDockerStreamState(multiplexed = false) {
	return {
		headersStripped: false,
		isChunked: false,
		headerBuffer: Buffer.alloc(0),
		chunkBuffer: Buffer.alloc(0),
		chunkSize: null,
		chunkEnded: false,
		multiplexed,
		streamBuffer: Buffer.alloc(0)
	};
}

function decodeChunkedDockerBody(data, state) {
	state.chunkBuffer = Buffer.concat([state.chunkBuffer, data]);
	const chunks = [];

	while (!state.chunkEnded) {
		if (state.chunkSize === null) {
			const lineEnd = state.chunkBuffer.indexOf('\r\n');
			if (lineEnd < 0) break;

			const sizeText = state.chunkBuffer.slice(0, lineEnd).toString('ascii').split(';', 1)[0];
			const size = parseInt(sizeText, 16);
			if (!Number.isFinite(size) || size < 0) {
				state.chunkEnded = true;
				chunks.push(state.chunkBuffer);
				state.chunkBuffer = Buffer.alloc(0);
				break;
			}

			state.chunkBuffer = state.chunkBuffer.slice(lineEnd + 2);
			state.chunkSize = size;
			if (size === 0) {
				state.chunkEnded = true;
				state.chunkBuffer = Buffer.alloc(0);
				break;
			}
		}

		if (state.chunkBuffer.length < state.chunkSize + 2) break;
		chunks.push(state.chunkBuffer.slice(0, state.chunkSize));
		state.chunkBuffer = state.chunkBuffer.slice(state.chunkSize + 2);
		state.chunkSize = null;
	}

	return chunks;
}

function processDockerStreamChunk(data, state) {
	let buffer = Buffer.isBuffer(data) ? data : Buffer.from(data);
	if (!state.headersStripped) {
		state.headerBuffer = Buffer.concat([state.headerBuffer, buffer]);
		const headerEnd = state.headerBuffer.indexOf('\r\n\r\n');
		if (headerEnd < 0) return [];

		const headers = state.headerBuffer.slice(0, headerEnd).toString('ascii').toLowerCase();
		state.isChunked = headers.includes('transfer-encoding: chunked');
		buffer = state.headerBuffer.slice(headerEnd + 4);
		state.headerBuffer = Buffer.alloc(0);
		state.headersStripped = true;
	}

	const bodyChunks = state.isChunked ? decodeChunkedDockerBody(buffer, state) : [buffer];
	const output = [];
	for (const body of bodyChunks) {
		if (!body.length) continue;
		if (!state.multiplexed) {
			output.push(body.toString('utf-8'));
			continue;
		}

		state.streamBuffer = Buffer.concat([state.streamBuffer, body]);
		while (state.streamBuffer.length > 0) {
			if (state.streamBuffer.length < 8) break;

			const streamType = state.streamBuffer.readUInt8(0);
			const frameSize = state.streamBuffer.readUInt32BE(4);
			if (
				streamType > 2 ||
				state.streamBuffer[1] !== 0 ||
				state.streamBuffer[2] !== 0 ||
				state.streamBuffer[3] !== 0 ||
				frameSize > 10 * 1024 * 1024
			) {
				// TTY output is normally raw. Fall back to raw output if a Docker
				// proxy did not preserve the expected multiplexed framing.
				output.push(state.streamBuffer.toString('utf-8'));
				state.streamBuffer = Buffer.alloc(0);
				state.multiplexed = false;
				break;
			}

			if (state.streamBuffer.length < 8 + frameSize) break;
			if (streamType === 1 || streamType === 2) {
				output.push(state.streamBuffer.slice(8, 8 + frameSize).toString('utf-8'));
			}
			state.streamBuffer = state.streamBuffer.slice(8 + frameSize);
		}
	}

	return output;
}

async function handleTerminalConnection(ws, url, connId) {
	const pathParts = url.pathname.split('/');
	const containerIdIndex = pathParts.indexOf('containers') + 1;
	const containerId = pathParts[containerIdIndex];
	const mode = url.searchParams.get('mode') === 'attach' ? 'attach' : 'exec';
	const shell = url.searchParams.get('shell') || '/bin/sh';
	const user = url.searchParams.get('user') || 'root';
	const envIdParam = url.searchParams.get('envId');
	const envId = envIdParam ? parseInt(envIdParam, 10) : undefined;

	if (!containerId) {
		ws.send(JSON.stringify({ type: 'error', message: 'No container ID' }));
		ws.close();
		return;
	}

	// Fail closed: a terminal upgrade is rejected with 401 before it reaches here unless
	// authenticated, so ws.__auth is always set. Assert it explicitly so the env/exec
	// gates below never run on a null auth (never rely on the handshake invariant alone).
	if (!ws.__auth) {
		ws.close(1008, 'unauthenticated');
		return;
	}

	if (typeof globalThis.__canAccessEnvForUser === 'function') {
		try {
			const ok = await globalThis.__canAccessEnvForUser(ws.__auth, envId);
			if (!ok) {
				console.warn(`[WS] env access denied: user=${ws.__auth.username} envId=${envId}`);
				ws.send(JSON.stringify({ type: 'error', message: 'Access denied for this environment' }));
				ws.close(1008, 'env access denied');
				return;
			}
		} catch (err) {
			console.error('[WS] env access check failed:', err);
			ws.close(1011, 'internal error');
			return;
		}
	}

	// Opening a shell requires the containers:exec permission, same as the REST exec endpoint.
	if (typeof globalThis.__canExecForUser === 'function') {
		try {
			const allowed = await globalThis.__canExecForUser(ws.__auth, envId);
			if (!allowed) {
				console.warn(`[WS] exec denied: user=${ws.__auth.username} envId=${envId}`);
				ws.send(JSON.stringify({ type: 'error', message: 'Permission denied' }));
				ws.close(1008, 'exec permission denied');
				return;
			}
		} catch (err) {
			console.error('[WS] exec permission check failed:', err);
			ws.close(1011, 'internal error');
			return;
		}
	}

	try {
		// Resolve Docker target via SvelteKit app's database
		let target;
		if (typeof globalThis.__terminalGetTarget === 'function') {
			target = await globalThis.__terminalGetTarget(envId);
		} else {
			// Fallback: local socket only (SvelteKit not yet loaded)
			target = { type: 'socket', connectionType: 'socket', socketPath: process.env.DOCKER_SOCKET || '/var/run/docker.sock' };
		}

		// Hawser Edge relays exec and (for capable agents) attach through the agent.
		if (target.connectionType === 'hawser-edge') {
			let multiplexed = false;
			if (mode === 'attach') {
				let containerTty = false;
				if (typeof globalThis.__terminalGetContainerTty === 'function') {
					try {
						containerTty = await globalThis.__terminalGetContainerTty(containerId, envId);
					} catch {
						// Keep multiplexing enabled if the TTY setting cannot be read.
					}
				}
				multiplexed = !containerTty;
			}
			handleEdgeExec(ws, connId, containerId, shell, user, target.environmentId, mode, multiplexed);
			return;
		}

		let execId = null;
		let streamPath;
		let streamBody = '';
		let multiplexed = false;
		if (mode === 'attach') {
			let containerTty = false;
			if (typeof globalThis.__terminalGetContainerTty === 'function') {
				try {
					containerTty = await globalThis.__terminalGetContainerTty(containerId, envId);
				} catch {
					// Keep multiplexing enabled if the TTY setting cannot be read.
				}
			}
			multiplexed = !containerTty;
			streamPath = `/containers/${encodeURIComponent(containerId)}/attach?stream=1&stdin=1&stdout=1&stderr=1`;
		} else {
			// Create exec instance via SvelteKit app (handles all connection types)
			if (typeof globalThis.__terminalCreateExec === 'function') {
				execId = await globalThis.__terminalCreateExec(containerId, shell, user, envId);
			} else {
				// Fallback: create exec directly via local socket
				execId = await createExecLocal(containerId, shell, user, target.socketPath || '/var/run/docker.sock');
			}
			streamPath = `/exec/${execId}/start`;
			streamBody = JSON.stringify({ Detach: false, Tty: true });
		}

		// Open raw bidirectional stream to Docker for the attach or exec session.
		let dockerStream;

		if (target.type === 'socket') {
			const socketPath = target.socketPath || '/var/run/docker.sock';
			dockerStream = createConnection({ path: socketPath });
		} else if (target.type === 'https' && target.tls) {
			const tlsOpts = {
				host: target.host,
				port: target.port,
				servername: target.host,
				rejectUnauthorized: target.tls.rejectUnauthorized ?? true
			};
			if (target.tls.ca) tlsOpts.ca = [target.tls.ca, ...rootCertificates];
			if (target.tls.cert) tlsOpts.cert = [target.tls.cert];
			if (target.tls.key) tlsOpts.key = target.tls.key;
			dockerStream = tlsConnect(tlsOpts);
		} else {
			// Plain HTTP (direct TCP or hawser-standard)
			dockerStream = createConnection({ host: target.host, port: target.port });
		}

		dockerStream.on('connect', () => {
			dockerStream.write(buildDockerStreamRequest(streamPath, target, streamBody));
		});

		const streamState = createDockerStreamState(multiplexed);

		dockerStream.on('data', (data) => {
			if (ws.readyState !== 1) return;

			for (const text of processDockerStreamChunk(data, streamState)) {
				if (text) ws.send(JSON.stringify({ type: 'output', data: text }));
			}
		});

		dockerStream.on('close', () => {
			if (ws.readyState === 1) {
				ws.send(JSON.stringify({ type: 'exit' }));
				ws.close();
			}
		});

		dockerStream.on('error', (err) => {
			console.error('[Terminal WS] Socket error:', err.message);
			if (ws.readyState === 1) {
				ws.send(JSON.stringify({ type: 'error', message: err.message }));
			}
		});

		// Forward terminal input from browser to Docker
		ws.on('message', (data) => {
			try {
				const msg = JSON.parse(data.toString());
				if (msg.type === 'input' && msg.data) {
					// Non-TTY attach has no pty to convert Enter (\r) to a newline.
					dockerStream.write(translateAttachInput(msg.data, multiplexed));
				} else if (msg.type === 'resize' && msg.cols && msg.rows) {
					if (mode === 'attach') {
						if (typeof globalThis.__terminalResizeContainer === 'function') {
							globalThis.__terminalResizeContainer(containerId, msg.cols, msg.rows, envId).catch(() => {});
						} else if (target.type === 'socket') {
							const socketPath = target.socketPath || '/var/run/docker.sock';
							const resizeReq = httpRequest({
								socketPath,
								path: `/containers/${encodeURIComponent(containerId)}/resize?h=${msg.rows}&w=${msg.cols}`,
								method: 'POST',
							}, () => {});
							resizeReq.on('error', () => {});
							resizeReq.end();
						}
					} else {
						// Use SvelteKit's resize function if available (works for all connection types)
						if (typeof globalThis.__terminalResizeExec === 'function') {
							globalThis.__terminalResizeExec(execId, msg.cols, msg.rows, envId).catch(() => {});
						} else {
							// Fallback: resize via local socket
							const socketPath = target.socketPath || '/var/run/docker.sock';
							const resizeReq = httpRequest({
								socketPath,
								path: `/exec/${execId}/resize?h=${msg.rows}&w=${msg.cols}`,
								method: 'POST',
							}, () => {});
							resizeReq.on('error', () => {});
							resizeReq.end();
						}
					}
				}
			} catch {}
		});

		ws.on('close', () => {
			dockerStream.destroy();
		});

		wsConnections.set(connId, { stream: dockerStream, ws });
	} catch (err) {
		console.error('[Terminal WS] Error:', err.message);
		if (ws.readyState === 1) {
			ws.send(JSON.stringify({ type: 'error', message: err.message }));
			ws.close();
		}
	}

	ws.on('close', () => {
		wsConnections.delete(connId);
	});

	// Without an 'error' listener, an emitted socket error (abrupt disconnect,
	// ECONNRESET) is re-thrown as an uncaught exception and crashes the process.
	ws.on('error', (err) => {
		console.error('[Terminal WS] Connection error:', err.message);
		wsConnections.delete(connId);
	});
}

/**
 * Handle Hawser Edge exec or attach session.
 * Sends exec/attach commands through the Hawser WebSocket relay. Attach reuses the
 * exec_* protocol with attach:true; for non-TTY containers the agent pipes a
 * multiplexed stream, demultiplexed here via the session's stream state.
 */
function handleEdgeExec(ws, connId, containerId, shell, user, environmentId, mode = 'exec', multiplexed = false) {
	if (typeof globalThis.__hawserSendMessage !== 'function') {
		ws.send(JSON.stringify({ type: 'error', message: 'Edge agent handler not ready' }));
		ws.close();
		return;
	}

	const attach = mode === 'attach';
	const execId = randomUUID();
	// Attach output is a raw hijacked stream (no HTTP headers); only the multiplexing
	// demux is needed, so seed the state with headersStripped already true.
	const streamState = attach ? createDockerStreamState(multiplexed) : null;
	if (streamState) streamState.headersStripped = true;
	edgeExecSessions.set(execId, { ws, execId, environmentId, streamState });

	// Send exec_start (attach:true reuses the exec relay) to the Hawser agent
	const execStartMsg = JSON.stringify({
		type: 'exec_start',
		execId,
		containerId,
		cmd: shell,
		user,
		cols: 120,
		rows: 30,
		attach
	});

	const sent = globalThis.__hawserSendMessage(environmentId, execStartMsg);
	if (!sent) {
		edgeExecSessions.delete(execId);
		ws.send(JSON.stringify({ type: 'error', message: 'Edge agent not connected' }));
		ws.close();
		return;
	}

	// Forward terminal input/resize from browser to agent
	ws.on('message', (data) => {
		try {
			const msg = JSON.parse(data.toString());
			if (msg.type === 'input' && msg.data) {
				// Non-TTY attach has no pty to convert Enter (\r) to a newline.
				const inputData = translateAttachInput(msg.data, attach && multiplexed);
				const inputMsg = JSON.stringify({
					type: 'exec_input',
					execId,
					data: Buffer.from(inputData).toString('base64')
				});
				globalThis.__hawserSendMessage(environmentId, inputMsg);
			} else if (msg.type === 'resize' && msg.cols && msg.rows) {
				const resizeMsg = JSON.stringify({
					type: 'exec_resize',
					execId,
					cols: msg.cols,
					rows: msg.rows
				});
				globalThis.__hawserSendMessage(environmentId, resizeMsg);
			}
		} catch {}
	});

	ws.on('close', () => {
		// Notify agent that exec session ended
		if (typeof globalThis.__hawserSendMessage === 'function') {
			const endMsg = JSON.stringify({
				type: 'exec_end',
				execId,
				reason: 'user_closed'
			});
			globalThis.__hawserSendMessage(environmentId, endMsg);
		}
		edgeExecSessions.delete(execId);
		wsConnections.delete(connId);
	});

	// An unhandled 'error' event would crash the process; log and clean up.
	ws.on('error', (err) => {
		console.error('[Edge exec WS] Connection error:', err.message);
		edgeExecSessions.delete(execId);
		wsConnections.delete(connId);
	});

	wsConnections.set(connId, { ws });
}

/**
 * Fallback: Create exec via local Docker socket (used before SvelteKit app is loaded)
 */
function createExecLocal(containerId, shell, user, socketPath) {
	const createBody = JSON.stringify({
		AttachStdin: true,
		AttachStdout: true,
		AttachStderr: true,
		Tty: true,
		Cmd: [shell],
		User: user
	});

	return new Promise((resolve, reject) => {
		const req = httpRequest({
			socketPath,
			path: `/containers/${containerId}/exec`,
			method: 'POST',
			headers: {
				'Content-Type': 'application/json',
				'Content-Length': Buffer.byteLength(createBody),
			},
		}, (res) => {
			const chunks = [];
			res.on('data', (chunk) => chunks.push(chunk));
			res.on('end', () => {
				try {
					const body = JSON.parse(Buffer.concat(chunks).toString());
					if (res.statusCode === 201 && body.Id) {
						resolve(body.Id);
					} else {
						reject(new Error(body.message || `Exec create failed: ${res.statusCode}`));
					}
				} catch (e) {
					reject(new Error('Failed to parse exec response'));
				}
			});
			res.on('error', reject);
		});
		req.on('error', reject);
		req.write(createBody);
		req.end();
	});
}

/**
 * Handle Hawser Edge WebSocket connections.
 * The full Hawser protocol is handled by the SvelteKit app
 * via the global hawser connection manager.
 */
function handleHawserConnection(ws, connId, remoteIp) {
	console.log('[Hawser WS] New connection pending authentication');

	ws.on('message', async (data) => {
		try {
			const msg = JSON.parse(data.toString());

			// Use the global hawser message handler injected by the SvelteKit app
			if (typeof globalThis.__hawserHandleMessage === 'function') {
				try {
					await globalThis.__hawserHandleMessage(ws, msg, connId, remoteIp);
				} catch (handlerError) {
					console.error('[Hawser WS] Handler error:', handlerError);
					// Don't close connection - let it recover
				}
			} else {
				console.warn('[Hawser WS] No global handler registered');
				ws.send(JSON.stringify({ type: 'error', message: 'Server not ready' }));
			}
		} catch (err) {
			console.error('[Hawser WS] Message parse error:', err.message);
		}
	});

	ws.on('close', () => {
		if (typeof globalThis.__hawserHandleDisconnect === 'function') {
			globalThis.__hawserHandleDisconnect(ws, connId);
		}
	});

	ws.on('error', (err) => {
		console.error('[Hawser WS] Connection error:', err.message);
	});
}

// Start the server
server.listen(PORT, HOST, () => {
	const scheme = useHttps ? 'https' : 'http';
	console.log(`Listening on ${scheme}://${HOST}:${PORT}/ with WebSocket`);
});