1 files changed, 35 insertions, 23 deletions

diff --git a/src/main/index.ts b/src/main/index.ts
index 0d93b17..d4d9b2d 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -11,7 +11,7 @@ import { CompilationManager } from './compilationManager'
 import { FileSyncBridge } from './fileSyncBridge'
 
 let mainWindow: BrowserWindow | null = null
-let ptyInstance: pty.IPty | null = null
+const ptyInstances = new Map<string, pty.IPty>()
 let overleafSock: OverleafSocket | null = null
 let compilationManager: CompilationManager | null = null
 let fileSyncBridge: FileSyncBridge | null = null
@@ -91,13 +91,16 @@ ipcMain.handle('synctex:editFromPdf', async (_e, pdfPath: string, page: number,
 
 // ── Terminal / PTY ───────────────────────────────────────────────
 
-ipcMain.handle('pty:spawn', async (_e, cwd: string) => {
-  if (ptyInstance) {
-    ptyInstance.kill()
+ipcMain.handle('pty:spawn', async (_e, id: string, cwd: string, cmd?: string, args?: string[]) => {
+  const existing = ptyInstances.get(id)
+  if (existing) {
+    existing.kill()
+    ptyInstances.delete(id)
   }
 
-  const shellPath = process.env.SHELL || '/bin/zsh'
-  ptyInstance = pty.spawn(shellPath, ['-l'], {
+  const shellPath = cmd || process.env.SHELL || '/bin/zsh'
+  const shellArgs = args || ['-l']
+  const instance = pty.spawn(shellPath, shellArgs, {
     name: 'xterm-256color',
     cols: 80,
     rows: 24,
@@ -105,28 +108,37 @@ ipcMain.handle('pty:spawn', async (_e, cwd: string) => {
     env: process.env as Record<string, string>
   })
 
-  ptyInstance.onData((data) => {
-    sendToRenderer('pty:data', data)
+  ptyInstances.set(id, instance)
+
+  instance.onData((data) => {
+    sendToRenderer(`pty:data:${id}`, data)
   })
 
-  ptyInstance.onExit(() => {
-    sendToRenderer('pty:exit')
+  instance.onExit(() => {
+    // Only delete if this is still the current instance (avoid race with re-spawn)
+    if (ptyInstances.get(id) === instance) {
+      sendToRenderer(`pty:exit:${id}`)
+      ptyInstances.delete(id)
+    }
   })
 })
 
-ipcMain.handle('pty:write', async (_e, data: string) => {
-  ptyInstance?.write(data)
+ipcMain.handle('pty:write', async (_e, id: string, data: string) => {
+  ptyInstances.get(id)?.write(data)
 })
 
-ipcMain.handle('pty:resize', async (_e, cols: number, rows: number) => {
+ipcMain.handle('pty:resize', async (_e, id: string, cols: number, rows: number) => {
   try {
-    ptyInstance?.resize(cols, rows)
+    ptyInstances.get(id)?.resize(cols, rows)
   } catch { /* ignore resize errors */ }
 })
 
-ipcMain.handle('pty:kill', async () => {
-  ptyInstance?.kill()
-  ptyInstance = null
+ipcMain.handle('pty:kill', async (_e, id: string) => {
+  const instance = ptyInstances.get(id)
+  if (instance) {
+    instance.kill()
+    ptyInstances.delete(id)
+  }
 })
 
 // ── Overleaf Web Session (for comments) ─────────────────────────
@@ -613,12 +625,15 @@ ipcMain.handle('ot:connect', async (_e, projectId: string) => {
     })
 
     // otUpdateApplied: server acknowledges our op (ack signal for OT client)
+    // Only ack when there's no 'op' field — presence of 'op' means it's a remote update, not our ack
     overleafSock.on('serverEvent', (name: string, args: unknown[]) => {
       if (name === 'otUpdateApplied') {
-        const update = args[0] as { doc?: string; v?: number } | undefined
-        if (update?.doc) {
+        const update = args[0] as { doc?: string; op?: unknown[]; v?: number } | undefined
+        if (update?.doc && !update.op) {
           sendToRenderer('ot:ack', { docId: update.doc })
         }
+      } else if (name === 'otUpdateError') {
+        console.log(`[ot:error] server rejected update:`, JSON.stringify(args).slice(0, 500))
       }
     })
 
@@ -650,9 +665,7 @@ ipcMain.handle('ot:connect', async (_e, projectId: string) => {
     // Set up file sync bridge for bidirectional sync
     const tmpDir = compilationManager.dir
     fileSyncBridge = new FileSyncBridge(overleafSock, tmpDir, docPathMap, pathDocMap, fileRefs, mainWindow!, projectId, overleafSessionCookie, overleafCsrfToken)
-    fileSyncBridge.start().catch((e) => {
-      console.log('[ot:connect] fileSyncBridge start error:', e)
-    })
+    await fileSyncBridge.start()
 
     return {
       success: true,
@@ -691,7 +704,6 @@ ipcMain.handle('ot:joinDoc', async (_e, docId: string) => {
   try {
     const result = await overleafSock.joinDoc(docId)
     const content = (result.docLines || []).join('\n')
-
     // Update compilation manager with doc content
     if (compilationManager && overleafSock.projectData) {
       const { docPathMap } = walkRootFolder(overleafSock.projectData.project.rootFolder)