Merge pull request #427 from eg-bole/fix/selection-popup-dismiss-cursor-insert

fix(editor/conversation): selection popup dismissal + caret-anchored draft insert (#425)

src/client/TextEditor.tsx

@@ -28,6 +28,7 @@ import { cmSurfaceTheme, CmThemeCompartment } from './cm-themes.ts'
 import { isDarkScheme, subscribeColorScheme } from './theme.ts'
 import { SandboxStatusBar } from './SandboxStatusBar.tsx'
 import { appendToDraft } from './conversation-draft.ts'
+import { useSelectionPopup } from './selection-popup.ts'
 import { buildSelectionInsert, linesOfSelection } from './selection-payload.ts'
 import { lazyChunkComponent } from './lazy-chunk.tsx'
 import { analyzeMarkdownHtml } from './markdown-html.ts'
@@ -41,13 +42,6 @@ import css from './sidebar.module.css'
 /** Previewable files (rendered output vs source editing). */
 type ViewMode = 'preview' | 'edit'
 
-/** The floating "add to conversation" action: payload + viewport anchor. */
-interface SelectionPopup {
-  insert: string
-  left: number
-  top: number
-}
-
 /**
  * The sandbox tokens of the HTML preview iframe. NO allow-same-origin (the
  * preview must stay in an opaque origin — with the route's own origin it
@@ -71,36 +65,23 @@ export function TextEditor(props: FileViewerProps) {
   const themeCompRef = useRef<CmThemeCompartment | null>(null)
   /** The app's resolved color scheme; the editor re-themes in place on flips. */
   const [dark, setDark] = useState(() => isDarkScheme())
-  /** The floating "add to conversation" popup (viewport-anchored; null = hidden). */
-  const [popup, setPopup] = useState<SelectionPopup | null>(null)
-  /** Live mirror of the popup state for click-time reads (no re-render race). */
-  const popupRef = useRef<SelectionPopup | null>(null)
   /** The markdown preview container (selection-containment + line lookup). */
   const mdRef = useRef<HTMLDivElement>(null)
+  const markdown = viewerId === 'markdown'
+  const html = viewerId === 'html'
 
-  const hidePopup = (): void => {
-    popupRef.current = null
-    setPopup(null)
-  }
-
-  /** Anchor the popup above the selection center; clamp inside the viewport. */
-  const showPopup = (insert: string, left: number, top: number): void => {
-    const next: SelectionPopup = {
-      insert,
-      left: Math.min(Math.max(left, 80), window.innerWidth - 80),
-      top,
-    }
-    popupRef.current = next
-    setPopup(next)
-  }
-
-  /** The popup button's click: insert the stored payload into the draft. */
-  const commitPopup = (): void => {
-    const current = popupRef.current
-    if (current === null) return
-    appendToDraft(ctx, scope.sessionId, current.insert)
-    hidePopup()
-  }
+  /**
+   * The floating "add to conversation" popup (viewport-anchored; null =
+   * hidden). The hook owns show/hide/commit plus the global dismissal
+   * listeners (outside mousedown, Escape, hidden tab/window, surface
+   * leaving the viewport) — see selection-popup.ts.
+   */
+  const selectionPopup = useSelectionPopup({
+    onCommit: (insert) => { appendToDraft(ctx, scope.sessionId, insert) },
+    // The surface that must stay on screen: the markdown preview container
+    // in preview mode, the CodeMirror host otherwise.
+    getSurface: () => (markdown && mode === 'preview' ? mdRef.current : hostRef.current),
+  })
 
   useEffect(() => subscribeColorScheme(() => { setDark(isDarkScheme()) }), [])
 
@@ -110,7 +91,7 @@ export function TextEditor(props: FileViewerProps) {
     setDraft(null)
     setDirty(false)
     setSaveState('idle')
-    hidePopup()
+    selectionPopup.hide()
   }, [content])
 
   // Create the CodeMirror editor once the content is loaded. The view owns
@@ -160,33 +141,33 @@ export function TextEditor(props: FileViewerProps) {
         ...(viewerId === 'code' || viewerId === 'markdown' ? [
           CodeMirrorView.updateListener.of((update) => {
             if (update.geometryChanged || update.viewportChanged) {
-              hidePopup()
+              selectionPopup.hide()
               return
             }
             if (!update.view.hasFocus) {
-              hidePopup()
+              selectionPopup.hide()
               return
             }
             if (!(update.selectionSet || update.docChanged || update.focusChanged)) return
             const sel = update.state.selection.main
             if (sel.empty) {
-              hidePopup()
+              selectionPopup.hide()
               return
             }
             const text = update.state.sliceDoc(sel.from, sel.to)
             if (text.trim() === '') {
-              hidePopup()
+              selectionPopup.hide()
               return
             }
             // Page coordinates (the document root may scroll); the popup is
             // position:fixed, so convert to viewport coordinates.
             const rect = update.view.coordsAtPos(sel.head)
             if (rect === null) {
-              hidePopup()
+              selectionPopup.hide()
               return
             }
             const doc = update.state.doc
-            showPopup(
+            selectionPopup.show(
               buildSelectionInsert(path, scope.cwd, {
                 start: doc.lineAt(sel.from).number,
                 end: doc.lineAt(sel.to).number,
@@ -223,7 +204,7 @@ export function TextEditor(props: FileViewerProps) {
   // it becomes visible again (CodeMirror sizes itself on reveal). A mode
   // flip also invalidates any anchored selection popup.
   useEffect(() => {
-    hidePopup()
+    selectionPopup.hide()
     if (mode === 'edit') viewRef.current?.requestMeasure()
   }, [mode])
 
@@ -254,8 +235,6 @@ export function TextEditor(props: FileViewerProps) {
     })
   }
 
-  const markdown = viewerId === 'markdown'
-  const html = viewerId === 'html'
   /** The markdown source the preview renders (draft wins over saved content). */
   const mdText = draft ?? content ?? ''
   /** The preview source: `mdText` with local image destinations rewritten to
@@ -307,22 +286,22 @@ export function TextEditor(props: FileViewerProps) {
   const handlePreviewMouseUp = (): void => {
     const sel = window.getSelection()
     if (sel === null || sel.isCollapsed || sel.anchorNode === null || sel.focusNode === null) {
-      hidePopup()
+      selectionPopup.hide()
       return
     }
     const host = mdRef.current
     if (host === null || !host.contains(sel.anchorNode) || !host.contains(sel.focusNode)) {
-      hidePopup()
+      selectionPopup.hide()
       return
     }
     const text = sel.toString()
     if (text.trim() === '') {
-      hidePopup()
+      selectionPopup.hide()
       return
     }
     const rect = sel.getRangeAt(0).getBoundingClientRect()
     const lines = linesOfSelection(mdText, text)
-    showPopup(
+    selectionPopup.show(
       buildSelectionInsert(path, scope.cwd, lines ?? undefined, text),
       rect.left + rect.width / 2,
       rect.top,
@@ -413,7 +392,7 @@ export function TextEditor(props: FileViewerProps) {
           className={css.editorMd}
           ref={mdRef}
           onMouseUp={handlePreviewMouseUp}
-          onScroll={hidePopup}
+          onScroll={selectionPopup.hide}
         >
           {/* The fence copy-button labels must come from this plugin's own
               dictionary: the DSH MarkdownText/CodeBlock are cordis-free and
@@ -461,15 +440,16 @@ export function TextEditor(props: FileViewerProps) {
           />
         </>
       )}
-      {popup !== null && createPortal(
+      {selectionPopup.popup !== null && createPortal(
         <button
           type="button"
+          ref={selectionPopup.buttonRef}
           className={css.selectionPopup}
-          style={{ left: popup.left, top: popup.top }}
+          style={{ left: selectionPopup.popup.left, top: selectionPopup.popup.top }}
           // Keep the selection (and CodeMirror focus) alive until the click
           // commits — without this the popup unmounts before click lands.
           onMouseDown={(event) => { event.preventDefault() }}
-          onClick={commitPopup}
+          onClick={selectionPopup.commit}
         >
           {t('addToConversation')}
         </button>,

src/client/conversation-draft.ts

@@ -1,29 +1,187 @@
 /**
- * Append text to the current session's composer draft through the
+ * Insert text into the current session's composer draft through the
  * conversation service — the shared path behind the explorer's @-reference
  * button and the viewer selection popup. The service is resolved lazily
  * through `ctx.get` (the inject-free read the app's own plugins use); a
  * missing service or scope degrades to a logged no-op, never a crash.
+ *
+ * Insert position (fixes upstream issue #425): the draft store only exposes
+ * the whole string (`getSnapshot().draft` + `setDraft(text)`) — there is no
+ * caret API on the conversation service. The composer's `<textarea>` keeps
+ * its last selection even while unfocused, so the live caret is probed from
+ * the DOM (guarded by a value-sync check), and the text is spliced at that
+ * position, replacing any live selection — with whitespace-aware joins, an
+ * insert into the middle of a sentence keeps single-space separation like
+ * the append path. An unknown/stale caret falls back to appending at the
+ * end (the pre-fix behavior).
+ *
+ * The caret is also *restored* after the insert: committing a programmatic
+ * draft change resets the controlled textarea's caret (observed landing at
+ * the start of the value), which would make every later insert probe the
+ * reset position and drift the stack (A|B + C + D ended up as |DACB). The
+ * placement (`placeComposerCaretAfterInsert`) puts the caret right after the
+ * inserted text once the value commit lands — the index accounts for the
+ * separating space on the left, so stacked inserts stay at their running
+ * position (A|B + C + D → ACD|B).
  */
 import type { Context, SidebarConversation } from '../context-types.ts'
 
+/** A resolved composer caret/selection in draft coordinates. */
+export interface DraftCaret {
+  start: number
+  end: number
+}
+
 /**
- * Append `text` to the session's composer draft (space-separated, like the
- * @-mentions). Returns false — and logs — when the conversation service or
- * the session scope is unavailable.
+ * The spliced draft plus the caret index (in that draft) right after the
+ * inserted text — the left-side separating space shifts the caret by one,
+ * which naive `start + text.length` misses (it would land before the tail).
+ */
+interface SpliceResult {
+  draft: string
+  caretAfter: number
+}
+
+/**
+ * Splice `text` into `draft` at `caret` (replacing any live selection) with
+ * whitespace-aware joins and report the caret position right after the
+ * inserted text. `caret === null` (position unknown) appends at the end,
+ * exactly like the original behavior.
+ */
+function spliceInsert(draft: string, text: string, caret: DraftCaret | null): SpliceResult {
+  if (caret === null || draft === '') {
+    const next = draft.trim() === '' ? text : `${draft} ${text}`
+    return { draft: next, caretAfter: next.length }
+  }
+  const prefix = draft.slice(0, caret.start)
+  const suffix = draft.slice(caret.end)
+  if (prefix === '' && suffix === '') return { draft: text, caretAfter: text.length }
+  // One separating space, but never doubled against adjacent whitespace
+  // (or the string edges) — mirrors how typing in the middle of a sentence
+  // behaves.
+  const left = prefix === '' || /\s$/.test(prefix) ? '' : ' '
+  const right = suffix === '' || /^\s/.test(suffix) ? '' : ' '
+  return {
+    draft: `${prefix}${left}${text}${right}${suffix}`,
+    caretAfter: prefix.length + left.length + text.length,
+  }
+}
+
+/**
+ * The spliced draft string (see {@link spliceInsert}); pure string math —
+ * unit-tested directly.
+ */
+export function insertAtCaret(draft: string, text: string, caret: DraftCaret | null): string {
+  return spliceInsert(draft, text, caret).draft
+}
+
+/**
+ * Locate the composer `<textarea>` in the conversation column: prefer the
+ * `data-phase`-tagged textarea (the composer's marker), falling back to any
+ * textarea in the column, then to a bare data-phase textarea (older host
+ * layouts without the column attribute). Null in jsdom-less hosts.
+ */
+function findComposerTextarea(): HTMLTextAreaElement | null {
+  if (typeof document === 'undefined') return null
+  const column = document.querySelector('#root [data-slot="conversation"]')
+  const find = (scope: ParentNode): HTMLTextAreaElement | null =>
+    scope.querySelector('textarea[data-phase]') ?? scope.querySelector('textarea')
+  return column !== null
+    ? find(column)
+    : document.querySelector<HTMLTextAreaElement>('textarea[data-phase]')
+}
+
+/**
+ * Resolve the composer's live caret from its DOM `<textarea>`. The draft
+ * store has no caret API, so the sidebar reads the composed input's selection
+ * directly; the value-sync check (`el.value === draft`) discards stale or
+ * wrong-composer reads — a caret must never be applied against a draft it
+ * was not measured on.
+ *
+ * Returns null when the composer is missing, disabled/read-only, out of
+ * sync with the store draft, or has no measurable selection (jsdom/odd
+ * hosts report null selectionStart/End).
+ */
+export function probeComposerCaret(draft: string): DraftCaret | null {
+  const el = findComposerTextarea()
+  if (el === null || el.disabled || el.readOnly) return null
+  if (el.value !== draft) return null
+  let start = el.selectionStart
+  let end = el.selectionEnd
+  if (typeof start !== 'number' || typeof end !== 'number') return null
+  if (!Number.isFinite(start) || !Number.isFinite(end)) return null
+  start = Math.max(0, Math.min(start, draft.length))
+  end = Math.max(start, Math.min(end, draft.length))
+  return { start, end }
+}
+
+/**
+ * Restore the composer caret to `caretIndex` after a programmatic
+ * `setDraft` commit. A controlled textarea update resets the caret (React
+ * commits the value asynchronously and the browser moves the caret to the
+ * start/end), so the placement is scheduled and retried across at most two
+ * animation frames (setTimeout fallback for jsdom), and only applied when
+ * the textarea still matches `expectedDraft` — a newer edit or a different
+ * composer wins the race untouched. The caret is clamped into the value
+ * bounds, mirroring how browsers clamp type-in positions.
+ */
+export function placeComposerCaretAfterInsert(expectedDraft: string, caretIndex: number): void {
+  let remaining = 2
+  let scheduled = false
+  const schedule = (fn: () => void): void => {
+    if (scheduled) return
+    scheduled = true
+    if (typeof requestAnimationFrame === 'function') requestAnimationFrame(fn)
+    else setTimeout(fn, 0)
+  }
+  const place = (): void => {
+    scheduled = false
+    if (remaining <= 0) return
+    remaining -= 1
+    const el = findComposerTextarea()
+    if (el === null || el.disabled || el.readOnly) return
+    if (el.value !== expectedDraft) {
+      // The commit has not landed yet (or a competing edit won) — one more
+      // frame before giving up.
+      schedule(place)
+      return
+    }
+    const clamped = Math.max(0, Math.min(caretIndex, el.value.length))
+    el.setSelectionRange(clamped, clamped)
+  }
+  schedule(place)
+}
+
+/**
+ * Insert `text` into the session's composer draft at the composer's live
+ * caret (see {@link probeComposerCaret}), falling back to appending at the
+ * end when the caret cannot be resolved. Returns false — and logs — when the
+ * conversation service or the session scope is unavailable.
  */
 export function appendToDraft(ctx: Context, sessionId: string, text: string): boolean {
   try {
     const actx = ctx.sessions.scope(sessionId)
-    if (actx === undefined) return false
+    if (actx === undefined) {
+      console.warn('[dsh-better-sidebar] draft insert skipped: no session scope', sessionId)
+      return false
+    }
     const conversation = ctx.get('conversation') as SidebarConversation | undefined
-    if (conversation === undefined) return false
+    if (conversation === undefined) {
+      console.warn('[dsh-better-sidebar] draft insert skipped: conversation service unavailable')
+      return false
+    }
     const input = conversation.input.for(actx)
     const draft = input.state.getSnapshot().draft
-    input.setDraft(draft.trim() === '' ? text : `${draft} ${text}`)
+    const caret = probeComposerCaret(draft)
+    const { draft: next, caretAfter } = spliceInsert(draft, text, caret)
+    input.setDraft(next)
+    // Put the caret right after the inserted text once the value commit
+    // lands — see the module doc for why this keeps stacked inserts at the
+    // running position.
+    placeComposerCaretAfterInsert(next, caretAfter)
     return true
   } catch (error) {
     console.warn('[dsh-better-sidebar] draft insert failed:', error)
     return false
   }
-}
+}

src/client/selection-popup.ts

@@ -0,0 +1,157 @@
+/**
+ * The floating "add selection to conversation" popup shared by the text
+ * viewers (markdown preview + the catch-all code viewer): a viewport-anchored
+ * button portaled to `document.body`, kept alive across the selection gesture
+ * and committed on click.
+ *
+ * Dismissal contract (fixes upstream issue #425): the popup must never
+ * outlive its editor surface. The sidebar keeps every tab MOUNTED — switching
+ * tabs only flips the pane cell to `display:none` and collapsing the panel
+ * translates it off-screen — while the portaled `position:fixed` button stays
+ * pinned to its viewport anchor, ignoring both. The caller already hides on
+ * surface scrolls, selection collapse and mode flips; this hook adds the
+ * global dismissal that covers everything else:
+ *
+ * - any `mousedown` outside the button (tab bar, composer, another pane,
+ *   the collapse toggle, …) closes it;
+ * - `Escape` closes it;
+ * - the document going hidden (`visibilitychange`) or the window losing
+ *   focus closes it;
+ * - an `IntersectionObserver` on the editor surface closes it as soon as the
+ *   surface leaves the viewport — the tab-switch (`display:none`) and
+ *   panel-collapse (translated off-screen) paths have no DOM events of their
+ *   own, so the geometry signal is the only reliable one.
+ *
+ * The button's own `mousedown` is never treated as an outside click: the
+ * caller preventDefaults it to keep the selection/caret alive until the
+ * click commits (the hook's capture-phase listener runs first and must not
+ * hide for it).
+ */
+import { useEffect, useRef, useState, type RefObject } from 'react'
+
+/** The floating "add to conversation" action: payload + viewport anchor. */
+export interface SelectionPopup {
+  insert: string
+  left: number
+  top: number
+}
+
+export interface SelectionPopupOptions {
+  /** Commit the payload into the composer draft (button click). */
+  onCommit(insert: string): void
+  /**
+   * The DOM surface that must stay on screen for the popup to live: the
+   * markdown preview container in preview mode, the CodeMirror host
+   * otherwise. Called lazily (refs are null until the content loads).
+   */
+  getSurface(): HTMLElement | null
+}
+
+export interface SelectionPopupControls {
+  /** The current popup (null = hidden). */
+  popup: SelectionPopup | null
+  /** Attach to the portaled button element. */
+  buttonRef: RefObject<HTMLButtonElement>
+  /** Anchor the popup above a selection (viewport-clamped). */
+  show(insert: string, left: number, top: number): void
+  /** Hide the popup (idempotent). */
+  hide(): void
+  /** The button's click: commit the stored payload, then hide. */
+  commit(): void
+}
+
+export function useSelectionPopup(options: SelectionPopupOptions): SelectionPopupControls {
+  // Latest-callback refs: the dismissal listeners live for the mount's
+  // lifetime, so they must not capture stale closures across renders.
+  const onCommitRef = useRef(options.onCommit)
+  const getSurfaceRef = useRef(options.getSurface)
+  onCommitRef.current = options.onCommit
+  getSurfaceRef.current = options.getSurface
+
+  const [popup, setPopup] = useState<SelectionPopup | null>(null)
+  /** Live mirror for click/event-time reads (no re-render race). */
+  const popupRef = useRef<SelectionPopup | null>(null)
+  /** The portaled button itself (for the outside-click guard). */
+  const buttonRef = useRef<HTMLButtonElement>(null)
+  /** The surface visibility observer (created lazily on open). */
+  const observerRef = useRef<IntersectionObserver | null>(null)
+
+  const show = (insert: string, left: number, top: number): void => {
+    const next: SelectionPopup = {
+      insert,
+      left: Math.min(Math.max(left, 80), window.innerWidth - 80),
+      top,
+    }
+    popupRef.current = next
+    setPopup(next)
+  }
+
+  const hide = (): void => {
+    popupRef.current = null
+    setPopup(null)
+  }
+
+  const commit = (): void => {
+    const current = popupRef.current
+    if (current === null) return
+    onCommitRef.current(current.insert)
+    hide()
+  }
+
+  // Global dismissal listeners, registered once; every handler reads the
+  // live popup ref so it no-ops while no popup is open.
+  useEffect(() => {
+    const onMouseDown = (event: MouseEvent): void => {
+      if (popupRef.current === null) return
+      const button = buttonRef.current
+      if (button !== null && (button === event.target || button.contains(event.target as Node))) return
+      hide()
+    }
+    const onKeyDown = (event: KeyboardEvent): void => {
+      if (event.key === 'Escape' && popupRef.current !== null) hide()
+    }
+    const onVisibilityChange = (): void => {
+      if (document.hidden && popupRef.current !== null) hide()
+    }
+    const onWindowBlur = (): void => {
+      if (popupRef.current !== null) hide()
+    }
+    document.addEventListener('mousedown', onMouseDown, true)
+    document.addEventListener('keydown', onKeyDown, true)
+    document.addEventListener('visibilitychange', onVisibilityChange)
+    window.addEventListener('blur', onWindowBlur)
+    return () => {
+      document.removeEventListener('mousedown', onMouseDown, true)
+      document.removeEventListener('keydown', onKeyDown, true)
+      document.removeEventListener('visibilitychange', onVisibilityChange)
+      window.removeEventListener('blur', onWindowBlur)
+      observerRef.current?.disconnect()
+      observerRef.current = null
+    }
+  }, [])
+
+  // Re-target the visibility observer whenever a popup opens: the surface
+  // refs may have been null at mount (content loads async, mode flips swap
+  // the preview container for the CodeMirror host), so the surface is only
+  // trustworthy at open time.
+  useEffect(() => {
+    if (popup === null) return
+    observerRef.current?.disconnect()
+    observerRef.current = null
+    if (typeof IntersectionObserver === 'undefined') return
+    const surface = getSurfaceRef.current()
+    if (surface === null) return
+    const observer = new IntersectionObserver((entries) => {
+      for (const entry of entries) {
+        if (!entry.isIntersecting) hide()
+      }
+    }, { threshold: 0 })
+    observerRef.current = observer
+    observer.observe(surface)
+    // eslint-disable-next-line react-hooks/exhaustive-deps -- the boolean
+    // flip is the only thing that must re-run this; an anchor move while
+    // open keeps the same surface.
+  }, [popup !== null])
+
+  return { popup, buttonRef, show, hide, commit }
+}