[Init] Initial commit - NetMesh terminal manager

electron/bridges/terminalFlowPauseArbiter.cjs

@@ -0,0 +1,87 @@
+"use strict";
+
+const { randomUUID } = require("node:crypto");
+
+function createTerminalFlowPauseArbiter(options = {}) {
+  const createLeaseId = options.createLeaseId || randomUUID;
+  const states = new Map();
+
+  const getState = (sessionId) => {
+    let state = states.get(sessionId);
+    if (!state) {
+      state = {
+        directPauseSenders: new Set(),
+        leases: new Map(),
+      };
+      states.set(sessionId, state);
+    }
+    return state;
+  };
+
+  const isPaused = (state) => (
+    state.directPauseSenders.size > 0 || state.leases.size > 0
+  );
+
+  const cleanup = (sessionId, state) => {
+    if (!isPaused(state)) states.delete(sessionId);
+  };
+
+  return {
+    setDirectPaused(sessionId, senderId, paused) {
+      const state = getState(sessionId);
+      if (paused) state.directPauseSenders.add(senderId);
+      else state.directPauseSenders.delete(senderId);
+      const effectivePaused = isPaused(state);
+      cleanup(sessionId, state);
+      return effectivePaused;
+    },
+
+    acquire(sessionId, senderId) {
+      const state = getState(sessionId);
+      const leaseId = createLeaseId();
+      state.leases.set(leaseId, senderId);
+      return { leaseId, paused: true };
+    },
+
+    owns(sessionId, senderId, leaseId) {
+      return states.get(sessionId)?.leases.get(leaseId) === senderId;
+    },
+
+    release(sessionId, senderId, leaseId, options = {}) {
+      const state = states.get(sessionId);
+      if (!state || state.leases.get(leaseId) !== senderId) {
+        return { success: false, paused: state ? isPaused(state) : false };
+      }
+      state.leases.delete(leaseId);
+      if (options.keepPaused) state.directPauseSenders.add(senderId);
+      const paused = isPaused(state);
+      cleanup(sessionId, state);
+      return { success: true, paused };
+    },
+
+    clearSender(senderId) {
+      const changed = [];
+      for (const [sessionId, state] of states) {
+        const before = isPaused(state);
+        state.directPauseSenders.delete(senderId);
+        for (const [leaseId, ownerId] of state.leases) {
+          if (ownerId === senderId) state.leases.delete(leaseId);
+        }
+        const paused = isPaused(state);
+        if (before !== paused) changed.push({ sessionId, paused });
+        cleanup(sessionId, state);
+      }
+      return changed;
+    },
+
+    clearSession(sessionId) {
+      states.delete(sessionId);
+    },
+
+    reset() {
+      states.clear();
+    },
+  };
+}
+
+module.exports = { createTerminalFlowPauseArbiter };