[Init] Initial commit - NetMesh terminal manager

electron/bridges/emitTerminalSessionData.cjs

@@ -0,0 +1,139 @@
+"use strict";
+
+const { trackEmitted } = require("./terminalFlowAck.cjs");
+const {
+  attachTerminalOutputPerfMeta,
+  createTerminalOutputPerfMeta,
+  logTerminalOutputPerf,
+} = require("./terminalPerformanceDiagnostics.cjs");
+
+let getSession = null;
+let outputChannel = null;
+let onSessionActivity = null;
+/** @type {Set<(sessionId: string, data: string) => void>} */
+const dataTaps = new Set();
+const emitPerfLogStateBySession = new Map();
+const MAX_EMIT_PERF_SESSION_STATES = 512;
+
+function retainTerminalSessionPerformanceState(key, state) {
+  emitPerfLogStateBySession.delete(key);
+  emitPerfLogStateBySession.set(key, state);
+  while (emitPerfLogStateBySession.size > MAX_EMIT_PERF_SESSION_STATES) {
+    const oldestKey = emitPerfLogStateBySession.keys().next().value;
+    if (oldestKey === undefined) break;
+    emitPerfLogStateBySession.delete(oldestKey);
+  }
+}
+
+function clearTerminalSessionPerformanceState(sessionId) {
+  if (!sessionId) return;
+  emitPerfLogStateBySession.delete(sessionId);
+}
+
+function configureTerminalSessionDataEmitter(options = {}) {
+  getSession = typeof options.getSession === "function" ? options.getSession : null;
+  outputChannel = options.outputChannel || null;
+  onSessionActivity = typeof options.onSessionActivity === "function"
+    ? options.onSessionActivity
+    : null;
+}
+
+function addTerminalDataTap(listener) {
+  if (typeof listener !== "function") return () => {};
+  dataTaps.add(listener);
+  return () => dataTaps.delete(listener);
+}
+
+function getEmitPerfLogDetails(sessionId, terminalPerf, options = {}) {
+  if (!terminalPerf) return null;
+  const key = sessionId || "__unknown__";
+  const now = Date.now();
+  const state = emitPerfLogStateBySession.get(key) || {
+    lastLoggedAt: 0,
+    batchChunks: 0,
+    batchChars: 0,
+    batchLineFeeds: 0,
+  };
+
+  state.batchChunks += 1;
+  state.batchChars += terminalPerf.chars;
+  state.batchLineFeeds += terminalPerf.lineFeeds;
+
+  const shouldLog =
+    state.lastLoggedAt === 0
+    || state.batchChars >= 512 * 1024
+    || state.batchLineFeeds >= 200
+    || now - state.lastLoggedAt >= 1000;
+
+  if (!shouldLog) {
+    retainTerminalSessionPerformanceState(key, state);
+    return null;
+  }
+
+  const details = {
+    id: terminalPerf.id,
+    sessionId,
+    chars: terminalPerf.chars,
+    lineFeeds: terminalPerf.lineFeeds,
+    batchChunks: state.batchChunks,
+    batchChars: state.batchChars,
+    batchLineFeeds: state.batchLineFeeds,
+    cols: options?.cols,
+    rows: options?.rows,
+  };
+
+  retainTerminalSessionPerformanceState(key, {
+    lastLoggedAt: now,
+    batchChunks: 0,
+    batchChars: 0,
+    batchLineFeeds: 0,
+  });
+  return details;
+}
+
+function emitTerminalSessionData(contents, sessionId, data, options = {}) {
+  const currentSession = getSession && sessionId ? getSession(sessionId) : null;
+  if (options.session && currentSession !== options.session) return false;
+  if (sessionId && data && onSessionActivity) {
+    try {
+      onSessionActivity({ sessionId, phase: "touch" });
+    } catch {
+      // Session activity tracking is best-effort and must not break output.
+    }
+  }
+  if (currentSession && sessionId && data) {
+    trackEmitted(currentSession, typeof data === "string" ? data.length : 0, sessionId);
+  }
+  if (sessionId && data) {
+    for (const tap of dataTaps) {
+      try {
+        tap(sessionId, data);
+      } catch (err) {
+        console.warn("[emitTerminalSessionData] tap failed", err);
+      }
+    }
+  }
+  const terminalPerf = createTerminalOutputPerfMeta(sessionId, data);
+  const meta = attachTerminalOutputPerfMeta(options?.meta, terminalPerf);
+  const emitPerfDetails = getEmitPerfLogDetails(sessionId, terminalPerf, options);
+  if (emitPerfDetails) {
+    logTerminalOutputPerf("backend-emit", emitPerfDetails);
+  }
+  if (outputChannel?.send?.(sessionId, data, meta)) return true;
+  const generation = options.session?._terminalSessionGeneration;
+  contents?.send("netcatty:data", {
+    sessionId,
+    data,
+    ...(meta ? { meta } : {}),
+    ...(Number.isSafeInteger(generation) ? { _terminalSessionGeneration: generation } : {}),
+  });
+  return true;
+}
+
+module.exports = {
+  configureTerminalSessionDataEmitter,
+  emitTerminalSessionData,
+  addTerminalDataTap,
+  clearTerminalSessionPerformanceState,
+  _getTerminalSessionPerformanceStateCountForTests: () => emitPerfLogStateBySession.size,
+};