chore: refactoring and tests, splitting up files (#12495)

packages/app/src/pages/session/use-session-hash-scroll.ts

@@ -0,0 +1,174 @@
+import { createEffect, on, onCleanup } from "solid-js"
+import { UserMessage } from "@opencode-ai/sdk/v2"
+
+export const messageIdFromHash = (hash: string) => {
+  const value = hash.startsWith("#") ? hash.slice(1) : hash
+  const match = value.match(/^message-(.+)$/)
+  if (!match) return
+  return match[1]
+}
+
+export const useSessionHashScroll = (input: {
+  sessionKey: () => string
+  sessionID: () => string | undefined
+  messagesReady: () => boolean
+  visibleUserMessages: () => UserMessage[]
+  turnStart: () => number
+  currentMessageId: () => string | undefined
+  pendingMessage: () => string | undefined
+  setPendingMessage: (value: string | undefined) => void
+  setActiveMessage: (message: UserMessage | undefined) => void
+  setTurnStart: (value: number) => void
+  scheduleTurnBackfill: () => void
+  autoScroll: { pause: () => void; forceScrollToBottom: () => void }
+  scroller: () => HTMLDivElement | undefined
+  anchor: (id: string) => string
+  scheduleScrollState: (el: HTMLDivElement) => void
+  consumePendingMessage: (key: string) => string | undefined
+}) => {
+  const clearMessageHash = () => {
+    if (!window.location.hash) return
+    window.history.replaceState(null, "", window.location.href.replace(/#.*$/, ""))
+  }
+
+  const updateHash = (id: string) => {
+    window.history.replaceState(null, "", `#${input.anchor(id)}`)
+  }
+
+  const scrollToElement = (el: HTMLElement, behavior: ScrollBehavior) => {
+    const root = input.scroller()
+    if (!root) return false
+
+    const a = el.getBoundingClientRect()
+    const b = root.getBoundingClientRect()
+    const top = a.top - b.top + root.scrollTop
+    root.scrollTo({ top, behavior })
+    return true
+  }
+
+  const scrollToMessage = (message: UserMessage, behavior: ScrollBehavior = "smooth") => {
+    input.setActiveMessage(message)
+
+    const msgs = input.visibleUserMessages()
+    const index = msgs.findIndex((m) => m.id === message.id)
+    if (index !== -1 && index < input.turnStart()) {
+      input.setTurnStart(index)
+      input.scheduleTurnBackfill()
+
+      requestAnimationFrame(() => {
+        const el = document.getElementById(input.anchor(message.id))
+        if (!el) {
+          requestAnimationFrame(() => {
+            const next = document.getElementById(input.anchor(message.id))
+            if (!next) return
+            scrollToElement(next, behavior)
+          })
+          return
+        }
+        scrollToElement(el, behavior)
+      })
+
+      updateHash(message.id)
+      return
+    }
+
+    const el = document.getElementById(input.anchor(message.id))
+    if (!el) {
+      updateHash(message.id)
+      requestAnimationFrame(() => {
+        const next = document.getElementById(input.anchor(message.id))
+        if (!next) return
+        if (!scrollToElement(next, behavior)) return
+      })
+      return
+    }
+    if (scrollToElement(el, behavior)) {
+      updateHash(message.id)
+      return
+    }
+
+    requestAnimationFrame(() => {
+      const next = document.getElementById(input.anchor(message.id))
+      if (!next) return
+      if (!scrollToElement(next, behavior)) return
+    })
+    updateHash(message.id)
+  }
+
+  const applyHash = (behavior: ScrollBehavior) => {
+    const hash = window.location.hash.slice(1)
+    if (!hash) {
+      input.autoScroll.forceScrollToBottom()
+      const el = input.scroller()
+      if (el) input.scheduleScrollState(el)
+      return
+    }
+
+    const messageId = messageIdFromHash(hash)
+    if (messageId) {
+      input.autoScroll.pause()
+      const msg = input.visibleUserMessages().find((m) => m.id === messageId)
+      if (msg) {
+        scrollToMessage(msg, behavior)
+        return
+      }
+      return
+    }
+
+    const target = document.getElementById(hash)
+    if (target) {
+      input.autoScroll.pause()
+      scrollToElement(target, behavior)
+      return
+    }
+
+    input.autoScroll.forceScrollToBottom()
+    const el = input.scroller()
+    if (el) input.scheduleScrollState(el)
+  }
+
+  createEffect(
+    on(input.sessionKey, (key) => {
+      if (!input.sessionID()) return
+      const messageID = input.consumePendingMessage(key)
+      if (!messageID) return
+      input.setPendingMessage(messageID)
+    }),
+  )
+
+  createEffect(() => {
+    if (!input.sessionID() || !input.messagesReady()) return
+    requestAnimationFrame(() => applyHash("auto"))
+  })
+
+  createEffect(() => {
+    if (!input.sessionID() || !input.messagesReady()) return
+
+    input.visibleUserMessages().length
+    input.turnStart()
+
+    const targetId = input.pendingMessage() ?? messageIdFromHash(window.location.hash)
+    if (!targetId) return
+    if (input.currentMessageId() === targetId) return
+
+    const msg = input.visibleUserMessages().find((m) => m.id === targetId)
+    if (!msg) return
+
+    if (input.pendingMessage() === targetId) input.setPendingMessage(undefined)
+    input.autoScroll.pause()
+    requestAnimationFrame(() => scrollToMessage(msg, "auto"))
+  })
+
+  createEffect(() => {
+    if (!input.sessionID() || !input.messagesReady()) return
+    const handler = () => requestAnimationFrame(() => applyHash("auto"))
+    window.addEventListener("hashchange", handler)
+    onCleanup(() => window.removeEventListener("hashchange", handler))
+  })
+
+  return {
+    clearMessageHash,
+    scrollToMessage,
+    applyHash,
+  }
+}