fix(app): terminal rework (#14217)

5 files changed, 122 insertions, 118 deletions

diff --git a/packages/app/src/components/terminal.tsx b/packages/app/src/components/terminal.tsx
index 085a79613..bd7ab2447 100644
--- a/packages/app/src/components/terminal.tsx
+++ b/packages/app/src/components/terminal.tsx
@@ -320,8 +320,6 @@ export const Terminal = (props: TerminalProps) => {
       const mod = loaded.mod
       const g = loaded.ghostty
 
-      const once = { value: false }
-
       const restore = typeof local.pty.buffer === "string" ? local.pty.buffer : ""
       const restoreSize =
         restore &&
@@ -416,20 +414,28 @@ export const Terminal = (props: TerminalProps) => {
         cleanups.push(() => window.removeEventListener("resize", handleResize))
       }
 
-      if (restore && restoreSize) {
-        t.write(restore, () => {
-          fit.fit()
-          scheduleSize(t.cols, t.rows)
-          if (typeof local.pty.scrollY === "number") t.scrollToLine(local.pty.scrollY)
-          startResize()
+      const write = (data: string) =>
+        new Promise<void>((resolve) => {
+          if (!output) {
+            resolve()
+            return
+          }
+          output.push(data)
+          output.flush(resolve)
         })
+
+      if (restore && restoreSize) {
+        await write(restore)
+        fit.fit()
+        scheduleSize(t.cols, t.rows)
+        if (typeof local.pty.scrollY === "number") t.scrollToLine(local.pty.scrollY)
+        startResize()
       } else {
         fit.fit()
         scheduleSize(t.cols, t.rows)
         if (restore) {
-          t.write(restore, () => {
-            if (typeof local.pty.scrollY === "number") t.scrollToLine(local.pty.scrollY)
-          })
+          await write(restore)
+          if (typeof local.pty.scrollY === "number") t.scrollToLine(local.pty.scrollY)
         }
         startResize()
       }
@@ -438,38 +444,32 @@ export const Terminal = (props: TerminalProps) => {
       // console.log("Scroll position:", ydisp)
       // })
 
+      const once = { value: false }
+      let closing = false
+
       const url = new URL(sdk.url + `/pty/${local.pty.id}/connect`)
       url.searchParams.set("directory", sdk.directory)
       url.searchParams.set("cursor", String(start !== undefined ? start : local.pty.buffer ? -1 : 0))
       url.protocol = url.protocol === "https:" ? "wss:" : "ws:"
       url.username = server.current?.http.username ?? ""
       url.password = server.current?.http.password ?? ""
+
       const socket = new WebSocket(url)
       socket.binaryType = "arraybuffer"
       ws = socket
-      cleanups.push(() => {
-        if (socket.readyState !== WebSocket.CLOSED && socket.readyState !== WebSocket.CLOSING) socket.close()
-      })
-      if (disposed) {
-        cleanup()
-        return
-      }
 
       const handleOpen = () => {
         local.onConnect?.()
         scheduleSize(t.cols, t.rows)
       }
       socket.addEventListener("open", handleOpen)
-      cleanups.push(() => socket.removeEventListener("open", handleOpen))
-
       if (socket.readyState === WebSocket.OPEN) handleOpen()
 
       const decoder = new TextDecoder()
-
       const handleMessage = (event: MessageEvent) => {
         if (disposed) return
+        if (closing) return
         if (event.data instanceof ArrayBuffer) {
-          // WebSocket control frame: 0x00 + UTF-8 JSON (currently { cursor }).
           const bytes = new Uint8Array(event.data)
           if (bytes[0] !== 0) return
           const json = decoder.decode(bytes.subarray(1))
@@ -491,20 +491,20 @@ export const Terminal = (props: TerminalProps) => {
         cursor += data.length
       }
       socket.addEventListener("message", handleMessage)
-      cleanups.push(() => socket.removeEventListener("message", handleMessage))
 
       const handleError = (error: Event) => {
         if (disposed) return
+        if (closing) return
         if (once.value) return
         once.value = true
         console.error("WebSocket error:", error)
         local.onConnectError?.(error)
       }
       socket.addEventListener("error", handleError)
-      cleanups.push(() => socket.removeEventListener("error", handleError))
 
       const handleClose = (event: CloseEvent) => {
         if (disposed) return
+        if (closing) return
         // Normal closure (code 1000) means PTY process exited - server event handles cleanup
         // For other codes (network issues, server restart), trigger error handler
         if (event.code !== 1000) {
@@ -514,7 +514,15 @@ export const Terminal = (props: TerminalProps) => {
         }
       }
       socket.addEventListener("close", handleClose)
-      cleanups.push(() => socket.removeEventListener("close", handleClose))
+
+      cleanups.push(() => {
+        closing = true
+        socket.removeEventListener("open", handleOpen)
+        socket.removeEventListener("message", handleMessage)
+        socket.removeEventListener("error", handleError)
+        socket.removeEventListener("close", handleClose)
+        if (socket.readyState !== WebSocket.CLOSED && socket.readyState !== WebSocket.CLOSING) socket.close(1000)
+      })
     }
 
     void run().catch((err) => {
diff --git a/packages/app/src/pages/session/terminal-panel.tsx b/packages/app/src/pages/session/terminal-panel.tsx
index 33421c386..73f61ab05 100644
--- a/packages/app/src/pages/session/terminal-panel.tsx
+++ b/packages/app/src/pages/session/terminal-panel.tsx
@@ -38,9 +38,34 @@ export function TerminalPanel() {
 
   const [store, setStore] = createStore({
     autoCreated: false,
+    everOpened: false,
     activeDraggable: undefined as string | undefined,
   })
 
+  const rendered = createMemo(() => isDesktop() && (opened() || store.everOpened))
+
+  createEffect(
+    on(open, (isOpen, prev) => {
+      if (isOpen) {
+        if (!store.everOpened) setStore("everOpened", true)
+        const activeId = terminal.active()
+        if (!activeId) return
+        if (document.activeElement instanceof HTMLElement) {
+          document.activeElement.blur()
+        }
+        setTimeout(() => focusTerminalById(activeId), 0)
+        return
+      }
+
+      if (!prev) return
+      const panel = document.getElementById("terminal-panel")
+      const activeElement = document.activeElement
+      if (!panel || !(activeElement instanceof HTMLElement)) return
+      if (!panel.contains(activeElement)) return
+      activeElement.blur()
+    }),
+  )
+
   createEffect(() => {
     if (!opened()) {
       setStore("autoCreated", false)
@@ -67,7 +92,7 @@ export function TerminalPanel() {
     on(
       () => terminal.active(),
       (activeId) => {
-        if (!activeId || !opened()) return
+        if (!activeId || !open()) return
         if (document.activeElement instanceof HTMLElement) {
           document.activeElement.blur()
         }
@@ -133,23 +158,32 @@ export function TerminalPanel() {
   }
 
   return (
-    <Show when={open()}>
+    <Show when={rendered()}>
       <div
         id="terminal-panel"
         role="region"
         aria-label={language.t("terminal.title")}
-        class="relative w-full flex flex-col shrink-0 border-t border-border-weak-base"
-        style={{ height: `${height()}px` }}
+        classList={{
+          "relative w-full flex flex-col shrink-0 overflow-hidden": true,
+          "border-t border-border-weak-base": open(),
+          "pointer-events-none": !open(),
+        }}
+        style={{
+          height: `${height()}px`,
+          display: open() ? "flex" : "none",
+        }}
       >
-        <ResizeHandle
-          direction="vertical"
-          size={height()}
-          min={100}
-          max={typeof window === "undefined" ? 1000 : window.innerHeight * 0.6}
-          collapseThreshold={50}
-          onResize={layout.terminal.resize}
-          onCollapse={close}
-        />
+        <Show when={open()}>
+          <ResizeHandle
+            direction="vertical"
+            size={height()}
+            min={100}
+            max={typeof window === "undefined" ? 1000 : window.innerHeight * 0.6}
+            collapseThreshold={50}
+            onResize={layout.terminal.resize}
+            onCollapse={close}
+          />
+        </Show>
         <Show
           when={terminal.ready()}
           fallback={
diff --git a/packages/opencode/src/pty/index.ts b/packages/opencode/src/pty/index.ts
index c98e99daf..72969a555 100644
--- a/packages/opencode/src/pty/index.ts
+++ b/packages/opencode/src/pty/index.ts
@@ -18,27 +18,26 @@ export namespace Pty {
 
   type Socket = {
     readyState: number
-    data: object
-    send: (data: string | Uint8Array<ArrayBuffer> | ArrayBuffer) => void
+    send: (data: string | Uint8Array | ArrayBuffer) => void
     close: (code?: number, reason?: string) => void
   }
 
-  // Bun's ServerWebSocket has a per-connection `.data` object (set during
-  // `server.upgrade`) that changes when the underlying connection is recycled.
-  // We keep a reference to a stable part of it so output can't leak even when
-  // websocket objects are reused.
-  const token = (ws: Socket) => {
-    const data = ws.data
-    const events = (data as { events?: unknown }).events
-    if (events && typeof events === "object") return events
+  type Subscriber = {
+    id: number
+  }
 
-    const url = (data as { url?: unknown }).url
-    if (url && typeof url === "object") return url
+  const sockets = new WeakMap<object, number>()
+  const owners = new WeakMap<object, string>()
+  let socketCounter = 0
 
-    return data
+  const tagSocket = (ws: Socket) => {
+    if (!ws || typeof ws !== "object") return
+    const next = (socketCounter = (socketCounter + 1) % Number.MAX_SAFE_INTEGER)
+    sockets.set(ws, next)
+    return next
   }
 
-  // WebSocket control frame: 0x00 + UTF-8 JSON (currently { cursor }).
+  // WebSocket control frame: 0x00 + UTF-8 JSON.
   const meta = (cursor: number) => {
     const json = JSON.stringify({ cursor })
     const bytes = encoder.encode(json)
@@ -102,7 +101,7 @@ export namespace Pty {
     buffer: string
     bufferCursor: number
     cursor: number
-    subscribers: Map<Socket, object>
+    subscribers: Map<Socket, Subscriber>
   }
 
   const state = Instance.state(
@@ -185,13 +184,13 @@ export namespace Pty {
     ptyProcess.onData((chunk) => {
       session.cursor += chunk.length
 
-      for (const [ws, data] of session.subscribers) {
+      for (const [ws, sub] of session.subscribers) {
         if (ws.readyState !== 1) {
           session.subscribers.delete(ws)
           continue
         }
 
-        if (token(ws) !== data) {
+        if (typeof ws === "object" && sockets.get(ws) !== sub.id) {
           session.subscribers.delete(ws)
           continue
         }
@@ -280,6 +279,25 @@ export namespace Pty {
     }
     log.info("client connected to session", { id })
 
+    const socketId = tagSocket(ws)
+    if (socketId === undefined) {
+      ws.close()
+      return
+    }
+
+    const previous = owners.get(ws)
+    if (previous && previous !== id) {
+      state().get(previous)?.subscribers.delete(ws)
+    }
+
+    owners.set(ws, id)
+    session.subscribers.set(ws, { id: socketId })
+
+    const cleanup = () => {
+      session.subscribers.delete(ws)
+      if (owners.get(ws) === id) owners.delete(ws)
+    }
+
     const start = session.bufferCursor
     const end = session.cursor
 
@@ -300,6 +318,7 @@ export namespace Pty {
           ws.send(data.slice(i, i + BUFFER_CHUNK))
         }
       } catch {
+        cleanup()
         ws.close()
         return
       }
@@ -308,23 +327,17 @@ export namespace Pty {
     try {
       ws.send(meta(end))
     } catch {
+      cleanup()
       ws.close()
       return
     }
-
-    if (!ws.data || typeof ws.data !== "object") {
-      ws.close()
-      return
-    }
-
-    session.subscribers.set(ws, token(ws))
     return {
       onMessage: (message: string | ArrayBuffer) => {
         session.process.write(String(message))
       },
       onClose: () => {
         log.info("client disconnected from session", { id })
-        session.subscribers.delete(ws)
+        cleanup()
       },
     }
   }
diff --git a/packages/opencode/src/server/routes/pty.ts b/packages/opencode/src/server/routes/pty.ts
index d516859f7..368c9612b 100644
--- a/packages/opencode/src/server/routes/pty.ts
+++ b/packages/opencode/src/server/routes/pty.ts
@@ -163,18 +163,13 @@ export const PtyRoutes = lazy(() =>
 
         type Socket = {
           readyState: number
-          data: object
-          send: (data: string | Uint8Array<ArrayBuffer> | ArrayBuffer) => void
+          send: (data: string | Uint8Array | ArrayBuffer) => void
           close: (code?: number, reason?: string) => void
         }
 
         const isSocket = (value: unknown): value is Socket => {
           if (!value || typeof value !== "object") return false
           if (!("readyState" in value)) return false
-          if (!("data" in value)) return false
-          if (!((value as { data?: unknown }).data && typeof (value as { data?: unknown }).data === "object")) {
-            return false
-          }
           if (!("send" in value) || typeof (value as { send?: unknown }).send !== "function") return false
           if (!("close" in value) || typeof (value as { close?: unknown }).close !== "function") return false
           return typeof (value as { readyState?: unknown }).readyState === "number"
@@ -182,12 +177,12 @@ export const PtyRoutes = lazy(() =>
 
         return {
           onOpen(_event, ws) {
-            const raw = ws.raw
-            if (!isSocket(raw)) {
+            const socket = ws.raw
+            if (!isSocket(socket)) {
               ws.close()
               return
             }
-            handler = Pty.connect(id, raw, cursor)
+            handler = Pty.connect(id, socket, cursor)
           },
           onMessage(event) {
             if (typeof event.data !== "string") return
diff --git a/packages/opencode/test/pty/pty-output-isolation.test.ts b/packages/opencode/test/pty/pty-output-isolation.test.ts
index 337280d18..b80d37345 100644
--- a/packages/opencode/test/pty/pty-output-isolation.test.ts
+++ b/packages/opencode/test/pty/pty-output-isolation.test.ts
@@ -18,7 +18,6 @@ describe("pty", () => {
 
           const ws = {
             readyState: 1,
-            data: { events: { connection: "a" } },
             send: (data: unknown) => {
               outA.push(typeof data === "string" ? data : Buffer.from(data as Uint8Array).toString("utf8"))
             },
@@ -31,7 +30,6 @@ describe("pty", () => {
           Pty.connect(a.id, ws as any)
 
           // Now "reuse" the same ws object for another connection.
-          ws.data = { events: { connection: "b" } }
           ws.send = (data: unknown) => {
             outB.push(typeof data === "string" ? data : Buffer.from(data as Uint8Array).toString("utf8"))
           }
@@ -53,48 +51,4 @@ describe("pty", () => {
       },
     })
   })
-
-  test("does not leak output when Bun recycles websocket objects before re-connect", async () => {
-    await using dir = await tmpdir({ git: true })
-
-    await Instance.provide({
-      directory: dir.path,
-      fn: async () => {
-        const a = await Pty.create({ command: "cat", title: "a" })
-        try {
-          const outA: string[] = []
-          const outB: string[] = []
-
-          const ws = {
-            readyState: 1,
-            data: { events: { connection: "a" } },
-            send: (data: unknown) => {
-              outA.push(typeof data === "string" ? data : Buffer.from(data as Uint8Array).toString("utf8"))
-            },
-            close: () => {
-              // no-op (simulate abrupt drop)
-            },
-          }
-
-          // Connect "a" first.
-          Pty.connect(a.id, ws as any)
-          outA.length = 0
-
-          // Simulate Bun reusing the same websocket object for another connection
-          // before the new onOpen handler has a chance to tag it.
-          ws.data = { events: { connection: "b" } }
-          ws.send = (data: unknown) => {
-            outB.push(typeof data === "string" ? data : Buffer.from(data as Uint8Array).toString("utf8"))
-          }
-
-          Pty.write(a.id, "AAA\n")
-          await Bun.sleep(100)
-
-          expect(outB.join("")).not.toContain("AAA")
-        } finally {
-          await Pty.remove(a.id)
-        }
-      },
-    })
-  })
 })