feat: add live Codex research chat and reusable deck sources

src/features/research/events.test.ts

@@ -0,0 +1,83 @@
+// @vitest-environment node
+import { expect, it, vi } from 'vitest'
+import { researchEvents } from './events.server'
+
+it('streams the initial state and pushes updates without another HTTP request', async () => {
+  let emit = (_value: { configured: boolean; run: null }) => {}
+  const unsubscribe = vi.fn()
+  const response = researchEvents(
+    new Request('http://127.0.0.1/api/research/events'),
+    (listener) => {
+      emit = listener
+      listener({ configured: false, run: null })
+      return unsubscribe
+    },
+  )
+  const reader = response.body?.getReader()
+  expect.assert.isDefined(reader)
+  const decoder = new TextDecoder()
+  expect(response.headers.get('content-type')).toContain('text/event-stream')
+  expect(decoder.decode((await reader.read()).value)).toBe(
+    'data: {"configured":false,"run":null}\n\n',
+  )
+  emit({ configured: true, run: null })
+  expect(decoder.decode((await reader.read()).value)).toContain(
+    '"configured":true',
+  )
+  await reader.cancel()
+  expect(unsubscribe).toHaveBeenCalledOnce()
+})
+
+it('unsubscribes on browser abort and sends current state on a fresh connection', async () => {
+  const controller = new AbortController()
+  const unsubscribe = vi.fn()
+  let configured = false
+  const subscribe = (
+    listener: (value: { configured: boolean; run: null }) => void,
+  ) => {
+    listener({ configured, run: null })
+    return unsubscribe
+  }
+  const first = researchEvents(
+    new Request('http://127.0.0.1/events', { signal: controller.signal }),
+    subscribe,
+  )
+  const firstReader = first.body?.getReader()
+  expect.assert.isDefined(firstReader)
+  await firstReader.read()
+  controller.abort()
+  expect(unsubscribe).toHaveBeenCalledOnce()
+  expect((await firstReader.read()).done).toBe(true)
+  configured = true
+  const second = researchEvents(
+    new Request('http://127.0.0.1/events'),
+    subscribe,
+  )
+  const reader = second.body?.getReader()
+  expect.assert.isDefined(reader)
+  expect(new TextDecoder().decode((await reader.read()).value)).toContain(
+    '"configured":true',
+  )
+  await reader.cancel()
+})
+
+it('bounds a slow viewer buffer while retaining the latest state', async () => {
+  let emit = (_value: { configured: boolean; run: null }) => {}
+  const response = researchEvents(
+    new Request('http://127.0.0.1/events'),
+    (listener) => {
+      emit = listener
+      listener({ configured: false, run: null })
+      return () => {}
+    },
+  )
+  for (let i = 0; i < 1000; i++) emit({ configured: false, run: null })
+  emit({ configured: true, run: null })
+  const reader = response.body?.getReader()
+  expect.assert.isDefined(reader)
+  await reader.read()
+  expect(new TextDecoder().decode((await reader.read()).value)).toContain(
+    '"configured":true',
+  )
+  await reader.cancel()
+})