feat(tui): add session render state dump

packages/opencode/src/cli/cmd/tui/routes/session/index.tsx

@@ -91,6 +91,7 @@ import { SessionRetry } from "@/session/retry"
 import { getRevertDiffFiles } from "../../util/revert-diff"
 import { OPENCODE_BASE_MODE, useBindings, useCommandShortcut, useOpencodeKeymap } from "../../keymap"
 import { PathFormatterProvider, usePathFormatter } from "../../context/path-format"
+import { InstallationChannel, InstallationVersion } from "@opencode-ai/core/installation/version"
 
 addDefaultParsers(parsers.parsers)
 
@@ -100,6 +101,7 @@ const GO_UPSELL_ACCOUNT_RATE_LIMIT_LAST_SEEN_AT = "go_upsell_account_rate_limit_
 const GO_UPSELL_ACCOUNT_RATE_LIMIT_DONT_SHOW = "go_upsell_account_rate_limit_dont_show"
 const GO_UPSELL_WINDOW = 86_400_000 // 24 hrs
 const GO_UPSELL_PROVIDERS = new Set(["opencode", "opencode-go"])
+const SESSION_RENDER_STATE_CHANNELS = new Set(["local", "dev", "beta"])
 
 function goUpsellKeys(action: SessionRetry.Retryable["action"]) {
   if (!action) return
@@ -415,6 +417,49 @@ export function Session() {
     }, 50)
   }
 
+  async function dumpRenderState() {
+    const timestamp = Date.now()
+    const maxTop = Math.max(0, scroll.scrollHeight - scroll.viewport.height)
+    const filename = `session-${route.sessionID.slice(0, 8)}-render-state-${timestamp}.json`
+    renderer.dumpBuffers(timestamp)
+    await Filesystem.writeJson(path.join(process.cwd(), filename), {
+      capturedAt: timestamp,
+      channel: InstallationChannel,
+      version: InstallationVersion,
+      sessionID: route.sessionID,
+      scroll: {
+        top: scroll.scrollTop,
+        height: scroll.scrollHeight,
+        viewportHeight: scroll.viewport.height,
+        maxTop,
+        atBottom: scroll.scrollTop >= maxTop,
+      },
+      messages: messages().map((message) => ({
+        id: message.id,
+        role: message.role,
+        parts: (sync.data.part[message.id] ?? []).map((part) => {
+          const renderable = scroll.findDescendantById(`text-${part.id}`)
+          return {
+            id: part.id,
+            type: part.type,
+            ...((part.type === "text" || part.type === "reasoning") && { textLength: part.text.length }),
+            ...(renderable && {
+              renderable: {
+                id: renderable.id,
+                x: renderable.x,
+                y: renderable.y,
+                width: renderable.width,
+                height: renderable.height,
+                visible: renderable.visible,
+              },
+            }),
+          }
+        }),
+      })),
+    })
+    toast.show({ message: `Session render state written to ${filename}`, variant: "success" })
+  }
+
   const local = useLocal()
 
   function enterChild(sessionID: string) {
@@ -1008,6 +1053,23 @@ export function Session() {
         dialog.clear()
       },
     },
+    ...(SESSION_RENDER_STATE_CHANNELS.has(InstallationChannel)
+      ? [
+          {
+            title: "Dump session render state",
+            value: "session.debug.dump_render_state",
+            category: "Debug",
+            run: async () => {
+              try {
+                await dumpRenderState()
+              } catch {
+                toast.show({ message: "Failed to dump session render state", variant: "error" })
+              }
+              dialog.clear()
+            },
+          },
+        ]
+      : []),
     {
       title: "Go to child session",
       value: "session.child.first",