---
phase: 26-pwa-performance
plan: 02
type: execute
wave: 2
depends_on:
  - 26-00
files_modified:
  - ui/src/components/MobileChatView.tsx
  - ui/src/components/MobileNavBar.tsx
  - ui/src/components/PullToRefresh.tsx
  - ui/src/components/ChatPanel.tsx
  - ui/src/components/ChatConversationList.tsx
  - ui/src/components/ChatInput.tsx
  - ui/src/hooks/usePullToRefresh.ts
  - ui/src/hooks/useMediaQuery.ts
autonomous: true
requirements:
  - PWA-03
  - PWA-04
  - PWA-05
must_haves:
  truths:
    - "On screens < 768px, chat renders as a full-screen view, not a slide-in panel"
    - "Mobile chat has a 48px header with back button, a sticky input bar at the bottom, and safe area padding"
    - "Bottom navigation bar on mobile shows Dashboard, Chat, and Inbox tabs with 44px min height"
    - "Pulling down on the conversation list on mobile triggers a refresh after 64px threshold"
    - "Chat input has minimum 44px touch targets on mobile and env(safe-area-inset-bottom) padding"
  artifacts:
    - path: "ui/src/components/MobileChatView.tsx"
      provides: "Full-screen mobile chat layout"
      min_lines: 40
    - path: "ui/src/components/MobileNavBar.tsx"
      provides: "Bottom navigation bar for mobile"
      min_lines: 30
    - path: "ui/src/components/PullToRefresh.tsx"
      provides: "Touch gesture wrapper for conversation list refresh"
      min_lines: 40
    - path: "ui/src/hooks/usePullToRefresh.ts"
      provides: "Touch gesture logic (touchstart/touchmove/touchend)"
      min_lines: 30
    - path: "ui/src/hooks/useMediaQuery.ts"
      provides: "Responsive breakpoint hook"
      min_lines: 10
  key_links:
    - from: "ui/src/components/ChatPanel.tsx"
      to: "ui/src/components/MobileChatView.tsx"
      via: "Conditional render based on useMediaQuery('(min-width: 768px)')"
      pattern: "MobileChatView"
    - from: "ui/src/components/ChatConversationList.tsx"
      to: "ui/src/components/PullToRefresh.tsx"
      via: "PullToRefresh wrapper around conversation list on mobile"
      pattern: "PullToRefresh"
---

<objective>
Create the responsive mobile layout: MobileChatView (full-screen chat on phones), MobileNavBar (bottom tabs), PullToRefresh (conversation list gesture), and update ChatPanel/ChatInput for mobile-safe rendering.

Purpose: Makes Nexus usable on phones and tablets with proper touch targets, safe area insets, and keyboard-aware layout (PWA-03, PWA-04, PWA-05).
Output: 3 new components, 2 new hooks, 3 updated components.
</objective>

<execution_context>
@$HOME/.claude/get-shit-done/workflows/execute-plan.md
@$HOME/.claude/get-shit-done/templates/summary.md
</execution_context>

<context>
@.planning/PROJECT.md
@.planning/ROADMAP.md
@.planning/STATE.md
@.planning/phases/26-pwa-performance/26-RESEARCH.md
@.planning/phases/26-pwa-performance/26-UI-SPEC.md
@ui/src/components/ChatPanel.tsx
@ui/src/components/ChatConversationList.tsx
@ui/src/components/ChatInput.tsx
@ui/src/components/SwipeToArchive.tsx

<interfaces>
From ui/src/components/ChatPanel.tsx:
```typescript
export function ChatPanel()
// Uses: useChatPanel() for { activeConversationId, setActiveConversationId, ... }
// Uses: useChatMessages(), useStreamingChat(), useBrainstormerDefault(), useChatBookmarks()
// Uses: useChatFileUpload()
// Renders: ChatConversationList, ChatMessageList, ChatInput, ChatAgentSelector, etc.
// Layout class: "hidden md:flex overflow-hidden transition-[width] duration-100 ease-out flex-shrink-0 border-l border-border flex-col bg-background"
```

From ui/src/components/SwipeToArchive.tsx (touch gesture reference):
```typescript
interface SwipeToArchiveProps {
  // Uses useRef for startX, useState for offset, native touch events
}
```
</interfaces>
</context>

<tasks>

<task type="auto">
  <name>Task 1: Create useMediaQuery hook, MobileNavBar, and PullToRefresh components</name>
  <files>ui/src/hooks/useMediaQuery.ts, ui/src/hooks/usePullToRefresh.ts, ui/src/components/MobileNavBar.tsx, ui/src/components/PullToRefresh.tsx</files>
  <read_first>
    - ui/src/components/SwipeToArchive.tsx
    - ui/src/components/SwipeToArchive.test.tsx
    - .planning/phases/26-pwa-performance/26-UI-SPEC.md
    - .planning/phases/26-pwa-performance/26-RESEARCH.md
  </read_first>
  <action>
1. Create `ui/src/hooks/useMediaQuery.ts`:
   - Export `function useMediaQuery(query: string): boolean`
   - Use `window.matchMedia(query)` with `addEventListener("change", ...)` for live updates
   - Return `matches` state
   - SSR-safe: default to `false` if `window` is undefined

2. Create `ui/src/hooks/usePullToRefresh.ts`:
   - Export `function usePullToRefresh({ onRefresh, threshold = 64, maxPull = 96, enabled = true }: { onRefresh: () => void; threshold?: number; maxPull?: number; enabled?: boolean })`
   - Use `useRef` for `startYRef` (touch start Y coordinate) and `containerRef` (scroll container)
   - Use `useState` for `pullDistance` (current pull offset) and `isRefreshing` (loading state)
   - Touch handlers (mirror SwipeToArchive.tsx convention — use native DOM events, not React synthetic):
     a. `handleTouchStart`: only capture if `containerRef.current?.scrollTop === 0`; store `e.touches[0].clientY` in `startYRef`
     b. `handleTouchMove`: calculate `dy = e.touches[0].clientY - startYRef.current`; if `dy > 0`, set `pullDistance` to `Math.min(dy, maxPull)`
     c. `handleTouchEnd`: if `pullDistance >= threshold`, call `navigator.vibrate?.(10)` for haptic feedback, set `isRefreshing = true`, call `onRefresh()`, then reset; else reset `pullDistance` to 0
   - Return `{ containerRef, pullDistance, isRefreshing, setIsRefreshing }`
   - `useEffect` to attach/detach touch listeners on `containerRef.current`

3. Create `ui/src/components/PullToRefresh.tsx`:
   - Props: `{ children: ReactNode; onRefresh: () => Promise<void> | void; enabled?: boolean }`
   - Use `usePullToRefresh` hook internally
   - Render a wrapper `div` with `ref={containerRef}` that contains:
     a. A pull indicator div at the top: spinner (using a `Loader2` icon from lucide-react with `animate-spin`) that appears when `pullDistance > 0`, opacity scales with `pullDistance / threshold`
     b. Text: show "Pull to refresh" when pulling, "Release to refresh" when `pullDistance >= 64`, spinner-only when `isRefreshing`
     c. Children rendered below the indicator
   - Spinner color: `text-primary` (uses `var(--primary)` per UI-SPEC)
   - Spinner size: 24px (`w-6 h-6`)

4. Create `ui/src/components/MobileNavBar.tsx`:
   - Props: `{ activeTab: "dashboard" | "chat" | "inbox" }`
   - Render a `nav` element with classes: `fixed bottom-0 left-0 right-0 z-50 flex items-center justify-around border-t border-border bg-background pb-[env(safe-area-inset-bottom)]`
   - Minimum height: `min-h-[44px]` (44px touch target per UI-SPEC)
   - Three tab buttons, each with:
     a. Icon from lucide-react: `LayoutDashboard` (Dashboard), `MessageSquare` (Chat), `Inbox` (Inbox)
     b. Label text below icon: "Dashboard", "Chat", "Inbox" in `text-xs`
     c. Active state: `text-primary` for icon and label (uses `var(--primary)`)
     d. Inactive state: `text-muted-foreground`
     e. Each button: `min-h-[44px] min-w-[44px]` touch target, `flex flex-col items-center justify-center gap-0.5`
   - Use `@/lib/router` Link component for navigation (Dashboard -> `/{prefix}/dashboard`, Inbox -> `/{prefix}/inbox/mine`)
   - Chat tab calls a callback prop `onChatTap` instead of navigating (opens chat view in-place)
  </action>
  <verify>
    <automated>test -f ui/src/hooks/useMediaQuery.ts && test -f ui/src/hooks/usePullToRefresh.ts && test -f ui/src/components/PullToRefresh.tsx && test -f ui/src/components/MobileNavBar.tsx && echo "PASS"</automated>
  </verify>
  <acceptance_criteria>
    - All 4 files exist
    - `grep "useMediaQuery" ui/src/hooks/useMediaQuery.ts` shows the hook export
    - `grep "threshold" ui/src/hooks/usePullToRefresh.ts` shows 64px default
    - `grep "min-h-\[44px\]" ui/src/components/MobileNavBar.tsx` shows touch target
    - `grep "text-primary" ui/src/components/MobileNavBar.tsx` shows active tab color
    - `grep "safe-area-inset-bottom" ui/src/components/MobileNavBar.tsx` shows safe area padding
    - `grep "navigator.vibrate" ui/src/hooks/usePullToRefresh.ts` shows haptic feedback
    - `pnpm --filter @paperclipai/ui build` succeeds
  </acceptance_criteria>
  <done>useMediaQuery hook, usePullToRefresh hook, PullToRefresh component, and MobileNavBar component created with proper touch targets, safe area insets, and haptic feedback.</done>
</task>

<task type="auto">
  <name>Task 2: Create MobileChatView and wire ChatPanel for responsive layout</name>
  <files>ui/src/components/MobileChatView.tsx, ui/src/components/ChatPanel.tsx, ui/src/components/ChatConversationList.tsx, ui/src/components/ChatInput.tsx</files>
  <read_first>
    - ui/src/components/ChatPanel.tsx
    - ui/src/components/ChatConversationList.tsx
    - ui/src/components/ChatInput.tsx
    - ui/src/components/MobileNavBar.tsx
    - ui/src/hooks/useMediaQuery.ts
    - .planning/phases/26-pwa-performance/26-UI-SPEC.md
  </read_first>
  <action>
1. Create `ui/src/components/MobileChatView.tsx`:
   - Full-screen mobile chat layout component
   - Props: same data props that ChatPanel passes to its children (activeConversationId, messages, streaming state, etc.) — extract what's needed by reading ChatPanel.tsx
   - Layout structure:
     a. Outer container: `fixed inset-0 z-40 flex flex-col bg-background`
     b. Header: `h-12 flex items-center px-3 border-b border-border gap-2` containing:
        - Back button: `<Button variant="ghost" size="icon">` with `ChevronLeft` icon and `aria-label="Back to conversations"`, calls `setActiveConversationId(null)` to return to conversation list
        - Conversation title: `<span className="flex-1 truncate text-sm font-medium">` showing conversation title
        - Agent selector icon button
     c. Message list: `<div className="flex-1 overflow-y-auto">` — renders `ChatMessageList` (reuse existing)
     d. Input bar: `<div className="sticky bottom-0 border-t border-border bg-background pb-[env(safe-area-inset-bottom)]">` — renders `ChatInput` (reuse existing)
   - Height calculation: use `h-[100dvh]` on the outer container (NOT `100vh` — per RESEARCH Pitfall 3)
   - Two views within MobileChatView:
     a. When `activeConversationId` is null: show conversation list (full screen) wrapped in `PullToRefresh`
     b. When `activeConversationId` is set: show header + message list + input

2. Update `ui/src/components/ChatPanel.tsx`:
   - Import `useMediaQuery` from `../hooks/useMediaQuery`
   - Import `MobileChatView` from `./MobileChatView`
   - At the top of ChatPanel function body, add: `const isDesktop = useMediaQuery("(min-width: 768px)");`
   - Conditional render: if `!isDesktop`, render `<MobileChatView />` passing all necessary props/context. If `isDesktop`, render existing desktop panel layout unchanged.
   - The existing `"hidden md:flex"` class on the desktop container already hides it on mobile, but the explicit conditional ensures MobileChatView renders on mobile.

3. Update `ui/src/components/ChatConversationList.tsx`:
   - Import `PullToRefresh` from `./PullToRefresh`
   - Import `useMediaQuery` from `../hooks/useMediaQuery`
   - Wrap the ScrollArea content in `<PullToRefresh onRefresh={refetch} enabled={isMobile}>` where `refetch` is from `useChatConversations` and `isMobile = !useMediaQuery("(min-width: 768px)")`
   - Each conversation list item already has adequate height but verify `min-h-[48px]` — add it if missing per UI-SPEC touch target rule

4. Update `ui/src/components/ChatInput.tsx`:
   - Add `pb-[env(safe-area-inset-bottom)]` class to the outermost input container (only on mobile — use a conditional class or always apply since it's a no-op on desktop)
   - Ensure the Send button has `min-h-[44px] min-w-[44px]` for touch target compliance
  </action>
  <verify>
    <automated>grep -q "MobileChatView" ui/src/components/ChatPanel.tsx && grep -q "100dvh" ui/src/components/MobileChatView.tsx && grep -q "PullToRefresh" ui/src/components/ChatConversationList.tsx && grep -q "safe-area-inset-bottom" ui/src/components/ChatInput.tsx && echo "PASS"</automated>
  </verify>
  <acceptance_criteria>
    - `MobileChatView.tsx` exists with `100dvh` height, back button with `aria-label="Back to conversations"`, sticky input bar with `safe-area-inset-bottom`
    - `ChatPanel.tsx` imports and conditionally renders `MobileChatView` for mobile
    - `ChatConversationList.tsx` wraps content in `PullToRefresh` for mobile
    - `ChatInput.tsx` has `safe-area-inset-bottom` padding
    - Send button has minimum 44px touch target
    - `pnpm --filter @paperclipai/ui build` succeeds
  </acceptance_criteria>
  <done>MobileChatView renders full-screen chat on mobile. ChatPanel conditionally renders mobile vs desktop. ChatConversationList has pull-to-refresh. ChatInput has safe area padding and proper touch targets.</done>
</task>

</tasks>

<verification>
- `pnpm --filter @paperclipai/ui build` succeeds
- MobileChatView uses `100dvh` not `100vh`
- MobileNavBar has 44px minimum touch targets
- PullToRefresh triggers after 64px threshold
- ChatPanel conditionally renders MobileChatView on mobile
- Safe area insets applied on input bar
</verification>

<success_criteria>
Mobile responsive layout complete. Phone users see full-screen chat, bottom nav, pull-to-refresh, and properly sized touch targets. Desktop layout unchanged.
</success_criteria>

<output>
After completion, create `.planning/phases/26-pwa-performance/26-02-SUMMARY.md`
</output>