feat: MVP-5 Sprint 3 - Sidebar, Work Mode, and Drafts

- Enhance note-connections with collapsible sections and recent versions
- Add work mode toggle in header for focused work
- Add draft autosave with 7-day TTL and recovery banner
- Save drafts on changes for new notes

src/components/draft-recovery-banner.tsx

@@ -0,0 +1,19 @@
+'use client'
+import { Button } from '@/components/ui/button'
+import { AlertCircle } from 'lucide-react'
+
+interface DraftRecoveryBannerProps {
+  onRestore: () => void
+  onDiscard: () => void
+}
+
+export function DraftRecoveryBanner({ onRestore, onDiscard }: DraftRecoveryBannerProps) {
+  return (
+    <div className="bg-yellow-50 border-yellow-200 p-3 rounded-lg flex items-center gap-3">
+      <AlertCircle className="h-5 w-5 text-yellow-600" />
+      <p className="text-sm text-yellow-800 flex-1">Se encontró un borrador guardado</p>
+      <Button size="sm" variant="outline" onClick={onDiscard}>Descartar</Button>
+      <Button size="sm" onClick={onRestore}>Recuperar</Button>
+    </div>
+  )
+}

src/components/header.tsx

@@ -6,6 +6,7 @@ import { usePathname } from 'next/navigation'
 import { Button } from '@/components/ui/button'
 import { Plus, FileText, Settings, Menu, X } from 'lucide-react'
 import { QuickAdd } from '@/components/quick-add'
+import { WorkModeToggle } from '@/components/work-mode-toggle'
 
 export function Header() {
   const pathname = usePathname()
@@ -43,6 +44,7 @@ export function Header() {
           </nav>
           <div className="flex items-center gap-2">
             <QuickAdd />
+            <WorkModeToggle />
             <Link href="/new">
               <Button size="sm" className="gap-1.5">
                 <Plus className="h-4 w-4" />
@@ -59,6 +61,7 @@ export function Header() {
           </Link>
           <div className="flex items-center gap-2">
             <QuickAdd />
+            <WorkModeToggle />
             <Button
               variant="ghost"
               size="sm"

src/components/note-connections.tsx

@@ -1,9 +1,10 @@
 'use client'
 
 import Link from 'next/link'
+import { useState, useEffect } from 'react'
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card'
 import { Badge } from '@/components/ui/badge'
-import { ArrowRight, Link2, RefreshCw, ExternalLink, Users } from 'lucide-react'
+import { ArrowRight, Link2, RefreshCw, ExternalLink, Users, ChevronDown, ChevronRight, History } from 'lucide-react'
 
 interface BacklinkInfo {
   id: string
@@ -38,12 +39,20 @@ function ConnectionGroup({
   icon: Icon,
   notes,
   emptyMessage,
+  isCollapsed,
+  onToggle,
 }: {
   title: string
   icon: React.ComponentType<{ className?: string }>
   notes: { id: string; title: string; type: string }[]
   emptyMessage: string
+  isCollapsed?: boolean
+  onToggle?: () => void
 }) {
+  if (notes.length === 0 && isCollapsed) {
+    return null
+  }
+
   if (notes.length === 0) {
     return (
       <div className="space-y-2">
@@ -59,12 +68,19 @@ function ConnectionGroup({
   return (
     <div className="space-y-2">
       <h4 className="text-sm font-medium flex items-center gap-2">
+        <button
+          onClick={onToggle}
+          className="flex items-center gap-2 hover:text-primary transition-colors"
+        >
+          {isCollapsed ? <ChevronRight className="h-4 w-4" /> : <ChevronDown className="h-4 w-4" />}
           <Icon className="h-4 w-4" />
           {title}
+        </button>
         <Badge variant="secondary" className="ml-auto text-xs">
           {notes.length}
         </Badge>
       </h4>
+      {!isCollapsed && (
         <div className="pl-6 space-y-1">
           {notes.map((note) => (
             <Link
@@ -76,6 +92,7 @@ function ConnectionGroup({
             </Link>
           ))}
         </div>
+      )}
     </div>
   )
 }
@@ -87,10 +104,24 @@ export function NoteConnections({
   relatedNotes,
   coUsedNotes,
 }: NoteConnectionsProps) {
+  const [collapsed, setCollapsed] = useState<Record<string, boolean>>({})
+  const [recentVersions, setRecentVersions] = useState<{ id: string; version: number; createdAt: string }[]>([])
+
+  useEffect(() => {
+    fetch(`/api/notes/${noteId}/versions`)
+      .then((r) => r.json())
+      .then((d) => setRecentVersions(d.data?.slice(0, 3) || []))
+      .catch(() => setRecentVersions([]))
+  }, [noteId])
+
   const hasAnyConnections =
     backlinks.length > 0 || outgoingLinks.length > 0 || relatedNotes.length > 0 || coUsedNotes.length > 0
 
-  if (!hasAnyConnections) {
+  const toggleCollapsed = (key: string) => {
+    setCollapsed((prev) => ({ ...prev, [key]: !prev[key] }))
+  }
+
+  if (!hasAnyConnections && recentVersions.length === 0) {
     return null
   }
 
@@ -113,6 +144,8 @@ export function NoteConnections({
             type: bl.sourceNote.type,
           }))}
           emptyMessage="Ningún otro documento enlaza a esta nota"
+          isCollapsed={collapsed['backlinks']}
+          onToggle={() => toggleCollapsed('backlinks')}
         />
 
         {/* Outgoing links - notes this note links TO */}
@@ -125,6 +158,8 @@ export function NoteConnections({
             type: ol.sourceNote.type,
           }))}
           emptyMessage="Esta nota no enlaza a ningún otro documento"
+          isCollapsed={collapsed['outgoing']}
+          onToggle={() => toggleCollapsed('outgoing')}
         />
 
         {/* Related notes - by content similarity and scoring */}
@@ -137,6 +172,8 @@ export function NoteConnections({
             type: rn.type,
           }))}
           emptyMessage="No hay notas relacionadas"
+          isCollapsed={collapsed['related']}
+          onToggle={() => toggleCollapsed('related')}
         />
 
         {/* Co-used notes - often viewed together */}
@@ -149,7 +186,26 @@ export function NoteConnections({
             type: cu.type,
           }))}
           emptyMessage="No hay notas co-usadas"
+          isCollapsed={collapsed['coused']}
+          onToggle={() => toggleCollapsed('coused')}
         />
+
+        {/* Recent versions */}
+        {recentVersions.length > 0 && (
+          <div className="space-y-2 pt-2 border-t">
+            <h4 className="text-sm font-medium flex items-center gap-2">
+              <History className="h-4 w-4" />
+              Versiones recientes
+            </h4>
+            <div className="pl-6 space-y-1">
+              {recentVersions.map((v) => (
+                <p key={v.id} className="text-xs text-muted-foreground">
+                  v{v.version} - {new Date(v.createdAt).toLocaleDateString()}
+                </p>
+              ))}
+            </div>
+          </div>
+        )}
       </CardContent>
     </Card>
   )

src/components/note-form.tsx

@@ -1,6 +1,6 @@
 'use client'
 
-import { useState, useRef, useEffect, useMemo } from 'react'
+import { useState, useRef, useEffect, useMemo, useCallback } from 'react'
 import { useRouter } from 'next/navigation'
 import { Note, NoteType, Tag } from '@/types/note'
 import { Button } from '@/components/ui/button'
@@ -11,6 +11,8 @@ import { Badge } from '@/components/ui/badge'
 import { X, Sparkles } from 'lucide-react'
 import { inferNoteType } from '@/lib/type-inference'
 import { useUnsavedChanges } from '@/hooks/use-unsaved-changes'
+import { saveDraft, loadDraft, deleteDraft } from '@/lib/drafts'
+import { DraftRecoveryBanner } from '@/components/draft-recovery-banner'
 
 // Command fields
 interface CommandFields {
@@ -622,6 +624,9 @@ export function NoteForm({ initialData, isEdit = false }: NoteFormProps) {
   const [isPinned, setIsPinned] = useState(initialData?.isPinned || false)
   const [isSubmitting, setIsSubmitting] = useState(false)
   const [isDirty, setIsDirty] = useState(false)
+  const [showDraftBanner, setShowDraftBanner] = useState(false)
+  const [draftLoaded, setDraftLoaded] = useState(false)
+  const draftLoadedRef = useRef(false)
 
   // Store initial values for dirty tracking
   const initialValuesRef = useRef({
@@ -650,13 +655,36 @@ export function NoteForm({ initialData, isEdit = false }: NoteFormProps) {
 
   useUnsavedChanges(isDirty)
 
+  // Serialized content for drafts and auto-suggest
+  const content = useMemo(() => serializeToMarkdown(type, fields), [type, fields])
+
+  // Load draft on mount (only for new notes)
+  useEffect(() => {
+    if (isEdit || draftLoadedRef.current) return
+    const draftKey = 'new'
+    const draft = loadDraft(draftKey)
+    if (draft) {
+      draftLoadedRef.current = true
+      setDraftLoaded(true)
+      setShowDraftBanner(true)
+    }
+  }, [isEdit])
+
+  // Debounced save draft on changes (only for new notes, after initial load)
+  useEffect(() => {
+    if (isEdit || !draftLoaded || draftLoadedRef.current) return
+    const draftKey = 'new'
+    const timeoutId = setTimeout(() => {
+      saveDraft(draftKey, { title, content, type, tags, savedAt: Date.now() })
+    }, 1000)
+    return () => clearTimeout(timeoutId)
+  }, [title, content, type, tags, isEdit, draftLoaded])
+
   const handleTypeChange = (newType: NoteType) => {
     setType(newType)
     setFields(defaultFields[newType])
   }
 
-  const content = useMemo(() => serializeToMarkdown(type, fields), [type, fields])
-
   // Auto-suggest tags based on title and content
   useEffect(() => {
     const fetchSuggestions = async () => {
@@ -762,6 +790,28 @@ export function NoteForm({ initialData, isEdit = false }: NoteFormProps) {
     return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
   }
 
+  const handleRestoreDraft = useCallback(() => {
+    const draftKey = 'new'
+    const draft = loadDraft(draftKey)
+    if (draft) {
+      setTitle(draft.title)
+      setType(draft.type as NoteType)
+      setFields(parseMarkdownToFields(draft.type as NoteType, draft.content))
+      setTags(draft.tags)
+      setShowDraftBanner(false)
+      draftLoadedRef.current = true
+      setDraftLoaded(true)
+    }
+  }, [])
+
+  const handleDiscardDraft = useCallback(() => {
+    const draftKey = 'new'
+    deleteDraft(draftKey)
+    setShowDraftBanner(false)
+    draftLoadedRef.current = true
+    setDraftLoaded(true)
+  }, [])
+
   const handleSubmit = async (e: React.FormEvent) => {
     e.preventDefault()
     setIsSubmitting(true)
@@ -787,6 +837,9 @@ export function NoteForm({ initialData, isEdit = false }: NoteFormProps) {
 
       if (res.ok) {
         setIsDirty(false)
+        if (!isEdit) {
+          deleteDraft('new')
+        }
         router.push('/notes')
         router.refresh()
       }
@@ -819,6 +872,9 @@ export function NoteForm({ initialData, isEdit = false }: NoteFormProps) {
 
   return (
     <form onSubmit={handleSubmit} className="space-y-4 max-w-2xl">
+      {showDraftBanner && (
+        <DraftRecoveryBanner onRestore={handleRestoreDraft} onDiscard={handleDiscardDraft} />
+      )}
       <div>
         <label className="block text-sm font-medium mb-1">Título</label>
         <Input

src/components/work-mode-toggle.tsx

@@ -0,0 +1,26 @@
+'use client'
+import { useState, useEffect } from 'react'
+import { getWorkMode, setWorkMode } from '@/lib/work-mode'
+import { Button } from '@/components/ui/button'
+import { Monitor, Eye } from 'lucide-react'
+
+export function WorkModeToggle() {
+  const [enabled, setEnabled] = useState(false)
+
+  useEffect(() => {
+    setEnabled(getWorkMode())
+  }, [])
+
+  const toggle = () => {
+    const newValue = !enabled
+    setEnabled(newValue)
+    setWorkMode(newValue)
+    // Could dispatch custom event for other components to listen
+  }
+
+  return (
+    <Button variant="ghost" size="sm" onClick={toggle} title="Modo trabajo">
+      {enabled ? <Eye className="h-4 w-4" /> : <Monitor className="h-4 w-4" />}
+    </Button>
+  )
+}

src/lib/drafts.ts

@@ -0,0 +1,36 @@
+const DRAFT_KEY_PREFIX = 'recall_draft_'
+const DRAFT_TTL = 7 * 24 * 60 * 60 * 1000 // 7 days
+
+interface Draft {
+  title: string
+  content: string
+  type: string
+  tags: string[]
+  savedAt: number
+}
+
+export function saveDraft(noteId: string, data: Draft): void {
+  if (typeof window === 'undefined') return
+  localStorage.setItem(DRAFT_KEY_PREFIX + noteId, JSON.stringify({ ...data, savedAt: Date.now() }))
+}
+
+export function loadDraft(noteId: string): Draft | null {
+  if (typeof window === 'undefined') return null
+  const stored = localStorage.getItem(DRAFT_KEY_PREFIX + noteId)
+  if (!stored) return null
+  try {
+    const draft = JSON.parse(stored) as Draft
+    if (Date.now() - draft.savedAt > DRAFT_TTL) {
+      deleteDraft(noteId)
+      return null
+    }
+    return draft
+  } catch {
+    return null
+  }
+}
+
+export function deleteDraft(noteId: string): void {
+  if (typeof window === 'undefined') return
+  localStorage.removeItem(DRAFT_KEY_PREFIX + noteId)
+}

src/lib/work-mode.ts

@@ -0,0 +1,11 @@
+const WORK_MODE_KEY = 'recall_work_mode'
+
+export function getWorkMode(): boolean {
+  if (typeof window === 'undefined') return false
+  return localStorage.getItem(WORK_MODE_KEY) === 'true'
+}
+
+export function setWorkMode(enabled: boolean): void {
+  if (typeof window === 'undefined') return
+  localStorage.setItem(WORK_MODE_KEY, String(enabled))
+}