'use client'

/**
 * Document Workflow Page (SDK Version)
 *
 * Split-view editor for legal documents with synchronized scrolling:
 * - Left: Current published version (read-only)
 * - Right: Draft/new version (editable)
 * - Approval workflow: Draft -> Review -> Approved -> Published
 * - DOCX upload with Word conversion
 * - Rich text editor with formatting toolbar
 */

import { useState, useEffect, useRef, useCallback } from 'react'
import { useSDK } from '@/lib/sdk'
import StepHeader from '@/components/sdk/StepHeader/StepHeader'

// Types
interface Document {
  id: string
  type: string
  name: string
  description: string
  mandatory: boolean
  created_at: string
  updated_at: string
}

interface Version {
  id: string
  document_id: string
  version: string
  language: string
  title: string
  content: string
  summary?: string
  status: 'draft' | 'review' | 'approved' | 'published' | 'archived' | 'rejected'
  created_at: string
  updated_at?: string
  created_by?: string
  approved_by?: string
  approved_at?: string
  rejection_reason?: string
}

interface ApprovalHistoryItem {
  action: string
  approver: string
  comment: string
  created_at: string
}

const STATUS_LABELS: Record<string, { label: string; color: string }> = {
  draft: { label: 'Entwurf', color: 'bg-yellow-100 text-yellow-700' },
  review: { label: 'In Pruefung', color: 'bg-blue-100 text-blue-700' },
  approved: { label: 'Freigegeben', color: 'bg-green-100 text-green-700' },
  published: { label: 'Veroeffentlicht', color: 'bg-emerald-100 text-emerald-700' },
  archived: { label: 'Archiviert', color: 'bg-slate-100 text-slate-700' },
  rejected: { label: 'Abgelehnt', color: 'bg-red-100 text-red-700' },
}

const DOCUMENT_TYPES: Record<string, string> = {
  terms: 'AGB',
  privacy: 'Datenschutzerklaerung',
  cookies: 'Cookie-Richtlinie',
  community_guidelines: 'Community-Richtlinien',
  imprint: 'Impressum',
}

export default function WorkflowPage() {
  const { state } = useSDK()
  const [documents, setDocuments] = useState<Document[]>([])
  const [versions, setVersions] = useState<Version[]>([])
  const [selectedDocument, setSelectedDocument] = useState<Document | null>(null)
  const [currentVersion, setCurrentVersion] = useState<Version | null>(null)
  const [draftVersion, setDraftVersion] = useState<Version | null>(null)
  const [loading, setLoading] = useState(true)
  const [saving, setSaving] = useState(false)
  const [error, setError] = useState<string | null>(null)
  const [editedContent, setEditedContent] = useState('')
  const [editedTitle, setEditedTitle] = useState('')
  const [editedSummary, setEditedSummary] = useState('')
  const [showHistory, setShowHistory] = useState(false)
  const [approvalHistory, setApprovalHistory] = useState<ApprovalHistoryItem[]>([])
  const [approvalComment, setApprovalComment] = useState('')
  const [showApprovalModal, setShowApprovalModal] = useState<'approve' | 'reject' | null>(null)
  const [showCompareView, setShowCompareView] = useState(false)
  const [uploading, setUploading] = useState(false)

  // Refs for synchronized scrolling
  const leftPanelRef = useRef<HTMLDivElement>(null)
  const rightPanelRef = useRef<HTMLDivElement>(null)
  const editorRef = useRef<HTMLDivElement>(null)
  const fileInputRef = useRef<HTMLInputElement>(null)
  const isScrolling = useRef(false)

  useEffect(() => {
    loadDocuments()
  }, [])

  useEffect(() => {
    if (selectedDocument) {
      loadVersions(selectedDocument.id)
    }
  }, [selectedDocument])

  // Synchronized scrolling setup
  const setupSyncScroll = useCallback(() => {
    const leftPanel = leftPanelRef.current
    const rightPanel = rightPanelRef.current

    if (!leftPanel || !rightPanel) return

    const handleLeftScroll = () => {
      if (isScrolling.current) return
      isScrolling.current = true

      const leftScrollPercent = leftPanel.scrollTop / (leftPanel.scrollHeight - leftPanel.clientHeight || 1)
      const rightMaxScroll = rightPanel.scrollHeight - rightPanel.clientHeight
      rightPanel.scrollTop = leftScrollPercent * rightMaxScroll

      setTimeout(() => { isScrolling.current = false }, 10)
    }

    const handleRightScroll = () => {
      if (isScrolling.current) return
      isScrolling.current = true

      const rightScrollPercent = rightPanel.scrollTop / (rightPanel.scrollHeight - rightPanel.clientHeight || 1)
      const leftMaxScroll = leftPanel.scrollHeight - leftPanel.clientHeight
      leftPanel.scrollTop = rightScrollPercent * leftMaxScroll

      setTimeout(() => { isScrolling.current = false }, 10)
    }

    leftPanel.addEventListener('scroll', handleLeftScroll)
    rightPanel.addEventListener('scroll', handleRightScroll)

    return () => {
      leftPanel.removeEventListener('scroll', handleLeftScroll)
      rightPanel.removeEventListener('scroll', handleRightScroll)
    }
  }, [])

  useEffect(() => {
    const cleanup = setupSyncScroll()
    return cleanup
  }, [setupSyncScroll, currentVersion, draftVersion])

  const loadDocuments = async () => {
    setLoading(true)
    try {
      const res = await fetch('/api/admin/consent/documents')
      if (res.ok) {
        const data = await res.json()
        setDocuments(data.documents || [])
        if (data.documents?.length > 0 && !selectedDocument) {
          setSelectedDocument(data.documents[0])
        }
      }
    } catch {
      setError('Fehler beim Laden der Dokumente')
    } finally {
      setLoading(false)
    }
  }

  const loadVersions = async (docId: string) => {
    try {
      const res = await fetch(`/api/admin/consent/documents/${docId}/versions`)
      if (res.ok) {
        const data = await res.json()
        const versionList = data.versions || []
        setVersions(versionList)

        const published = versionList.find((v: Version) => v.status === 'published')
        setCurrentVersion(published || null)

        const draft = versionList.find((v: Version) =>
          v.status === 'draft' || v.status === 'review' || v.status === 'approved'
        )
        if (draft) {
          setDraftVersion(draft)
          setEditedContent(draft.content)
          setEditedTitle(draft.title)
          setEditedSummary(draft.summary || '')
        } else {
          setDraftVersion(null)
          setEditedContent(published?.content || '')
          setEditedTitle(published?.title || '')
          setEditedSummary(published?.summary || '')
        }
      }
    } catch {
      setError('Fehler beim Laden der Versionen')
    }
  }

  // Rich text editor functions
  const formatDoc = (cmd: string, value: string | null = null) => {
    if (editorRef.current) {
      editorRef.current.focus()
      document.execCommand(cmd, false, value || undefined)
      updateEditorContent()
    }
  }

  const formatBlock = (tag: string) => {
    if (editorRef.current) {
      editorRef.current.focus()
      document.execCommand('formatBlock', false, `<${tag}>`)
      updateEditorContent()
    }
  }

  const insertLink = () => {
    const url = prompt('Link-URL eingeben:', 'https://')
    if (url && editorRef.current) {
      editorRef.current.focus()
      document.execCommand('createLink', false, url)
      updateEditorContent()
    }
  }

  const updateEditorContent = () => {
    if (editorRef.current) {
      setEditedContent(editorRef.current.innerHTML)
    }
  }

  // Word document upload
  const handleWordUpload = async (event: React.ChangeEvent<HTMLInputElement>) => {
    const file = event.target.files?.[0]
    if (!file) return

    setUploading(true)

    const formData = new FormData()
    formData.append('file', file)

    try {
      const response = await fetch('/api/admin/consent/versions/upload-word', {
        method: 'POST',
        body: formData
      })

      if (response.ok) {
        const data = await response.json()
        if (editorRef.current) {
          editorRef.current.innerHTML = data.html || '<p>Konvertierung fehlgeschlagen</p>'
          setEditedContent(editorRef.current.innerHTML)
        }
      } else {
        const errorData = await response.json()
        alert('Fehler beim Importieren: ' + (errorData.detail || 'Unbekannter Fehler'))
      }
    } catch (e) {
      alert('Fehler beim Hochladen: ' + (e instanceof Error ? e.message : 'Unbekannter Fehler'))
    } finally {
      setUploading(false)
      if (fileInputRef.current) {
        fileInputRef.current.value = ''
      }
    }
  }

  // Clean Word HTML on paste
  const handlePaste = (e: React.ClipboardEvent) => {
    const clipboardData = e.clipboardData
    const html = clipboardData.getData('text/html')

    if (html) {
      e.preventDefault()
      const cleanHtml = cleanWordHtml(html)
      document.execCommand('insertHTML', false, cleanHtml)
      updateEditorContent()
    }
  }

  const cleanWordHtml = (html: string): string => {
    let cleaned = html
    cleaned = cleaned.replace(/\s*mso-[^:]+:[^;]+;?/gi, '')
    cleaned = cleaned.replace(/\s*style="[^"]*"/gi, '')
    cleaned = cleaned.replace(/\s*class="[^"]*"/gi, '')
    cleaned = cleaned.replace(/<o:p><\/o:p>/gi, '')
    cleaned = cleaned.replace(/<\/?o:[^>]*>/gi, '')
    cleaned = cleaned.replace(/<\/?w:[^>]*>/gi, '')
    cleaned = cleaned.replace(/<\/?m:[^>]*>/gi, '')
    cleaned = cleaned.replace(/<span[^>]*>\s*<\/span>/gi, '')
    return cleaned
  }

  const createNewDraft = async () => {
    if (!selectedDocument) return
    setSaving(true)
    try {
      const nextVersion = getNextVersionNumber()
      const res = await fetch('/api/admin/consent/versions', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          document_id: selectedDocument.id,
          version: nextVersion,
          language: 'de',
          title: editedTitle || currentVersion?.title || selectedDocument.name,
          content: editedContent || currentVersion?.content || '',
          summary: editedSummary || currentVersion?.summary || '',
        }),
      })

      if (res.ok) {
        await loadVersions(selectedDocument.id)
      } else {
        const err = await res.json()
        setError(err.error || 'Fehler beim Erstellen des Entwurfs')
      }
    } catch {
      setError('Fehler beim Erstellen des Entwurfs')
    } finally {
      setSaving(false)
    }
  }

  const saveDraft = async () => {
    if (!draftVersion || draftVersion.status !== 'draft') return
    setSaving(true)
    try {
      const res = await fetch(`/api/admin/consent/versions/${draftVersion.id}`, {
        method: 'PUT',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          title: editedTitle,
          content: editedContent,
          summary: editedSummary,
        }),
      })

      if (res.ok) {
        await loadVersions(selectedDocument!.id)
      } else {
        const err = await res.json()
        setError(err.error || 'Fehler beim Speichern')
      }
    } catch {
      setError('Fehler beim Speichern')
    } finally {
      setSaving(false)
    }
  }

  const submitForReview = async () => {
    if (!draftVersion) return
    setSaving(true)
    try {
      const res = await fetch(`/api/admin/consent/versions/${draftVersion.id}/submit-review`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
      })

      if (res.ok) {
        await loadVersions(selectedDocument!.id)
      } else {
        const err = await res.json()
        setError(err.error || 'Fehler beim Einreichen')
      }
    } catch {
      setError('Fehler beim Einreichen zur Pruefung')
    } finally {
      setSaving(false)
    }
  }

  const approveVersion = async () => {
    if (!draftVersion) return
    setSaving(true)
    try {
      const res = await fetch(`/api/admin/consent/versions/${draftVersion.id}/approve`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ comment: approvalComment }),
      })

      if (res.ok) {
        setShowApprovalModal(null)
        setApprovalComment('')
        await loadVersions(selectedDocument!.id)
      } else {
        const err = await res.json()
        setError(err.error || 'Fehler bei der Freigabe')
      }
    } catch {
      setError('Fehler bei der Freigabe')
    } finally {
      setSaving(false)
    }
  }

  const rejectVersion = async () => {
    if (!draftVersion) return
    setSaving(true)
    try {
      const res = await fetch(`/api/admin/consent/versions/${draftVersion.id}/reject`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ reason: approvalComment }),
      })

      if (res.ok) {
        setShowApprovalModal(null)
        setApprovalComment('')
        await loadVersions(selectedDocument!.id)
      } else {
        const err = await res.json()
        setError(err.error || 'Fehler bei der Ablehnung')
      }
    } catch {
      setError('Fehler bei der Ablehnung')
    } finally {
      setSaving(false)
    }
  }

  const publishVersion = async () => {
    if (!draftVersion || draftVersion.status !== 'approved') return
    if (!confirm('Version wirklich veroeffentlichen? Die aktuelle Version wird archiviert.')) return

    setSaving(true)
    try {
      const res = await fetch(`/api/admin/consent/versions/${draftVersion.id}/publish`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
      })

      if (res.ok) {
        await loadVersions(selectedDocument!.id)
      } else {
        const err = await res.json()
        setError(err.error || 'Fehler beim Veroeffentlichen')
      }
    } catch {
      setError('Fehler beim Veroeffentlichen')
    } finally {
      setSaving(false)
    }
  }

  const getNextVersionNumber = () => {
    if (versions.length === 0) return '1.0'
    const latest = versions[0]
    const parts = latest.version.split('.')
    const major = parseInt(parts[0]) || 1
    const minor = parseInt(parts[1]) || 0
    return `${major}.${minor + 1}`
  }

  const loadApprovalHistory = async (versionId: string) => {
    try {
      const res = await fetch(`/api/admin/consent/versions/${versionId}/approval-history`)
      if (res.ok) {
        const data = await res.json()
        setApprovalHistory(data.approval_history || [])
      }
    } catch {
      console.error('Failed to load approval history')
    }
  }

  const isEditable = draftVersion?.status === 'draft' || !draftVersion

  return (
    <div className="space-y-6">
      <StepHeader stepId="workflow" showProgress={true} />

      {/* Error Banner */}
      {error && (
        <div className="bg-red-50 border border-red-200 rounded-lg p-4 flex items-center justify-between">
          <span className="text-red-700">{error}</span>
          <button onClick={() => setError(null)} className="text-red-500 hover:text-red-700">
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 18L18 6M6 6l12 12" />
            </svg>
          </button>
        </div>
      )}

      {/* Document Selector */}
      <div className="bg-white rounded-xl shadow-sm border p-4">
        <div className="flex items-center justify-between">
          <div className="flex items-center gap-4">
            <label className="text-sm font-medium text-slate-700">Dokument:</label>
            <select
              value={selectedDocument?.id || ''}
              onChange={(e) => {
                const doc = documents.find(d => d.id === e.target.value)
                setSelectedDocument(doc || null)
              }}
              className="px-3 py-2 border border-slate-300 rounded-lg text-sm min-w-[250px]"
            >
              <option value="">Dokument auswaehlen...</option>
              {documents.map((doc) => (
                <option key={doc.id} value={doc.id}>
                  {DOCUMENT_TYPES[doc.type] || doc.type} - {doc.name}
                </option>
              ))}
            </select>
          </div>

          <div className="flex items-center gap-2">
            {currentVersion && (
              <span className="text-sm text-slate-500">
                Aktuelle Version: <span className="font-medium">v{currentVersion.version}</span>
              </span>
            )}
            {draftVersion && (
              <span className={`px-2 py-1 rounded text-xs ${STATUS_LABELS[draftVersion.status].color}`}>
                {STATUS_LABELS[draftVersion.status].label}: v{draftVersion.version}
              </span>
            )}

            <button
              onClick={() => setShowCompareView(true)}
              className="px-3 py-2 text-sm text-purple-600 hover:text-purple-800 border border-purple-300 rounded-lg hover:bg-purple-50"
              title="Vollbild-Vergleich"
            >
              Vollbild
            </button>

            <button
              onClick={() => {
                setShowHistory(!showHistory)
                if (draftVersion && !showHistory) {
                  loadApprovalHistory(draftVersion.id)
                }
              }}
              className="px-3 py-2 text-sm text-slate-600 hover:text-slate-900 border border-slate-300 rounded-lg hover:bg-slate-50"
            >
              Historie
            </button>
          </div>
        </div>
      </div>

      {loading ? (
        <div className="flex items-center justify-center h-64">
          <div className="animate-spin rounded-full h-12 w-12 border-b-2 border-purple-600" />
        </div>
      ) : !selectedDocument ? (
        <div className="bg-white rounded-xl shadow-sm border p-12 text-center text-slate-500">
          Bitte waehlen Sie ein Dokument aus
        </div>
      ) : (
        <>
          {/* Workflow Status Bar */}
          <div className="bg-white rounded-xl shadow-sm border p-4">
            <div className="flex items-center justify-between">
              <div className="flex items-center gap-6">
                {['draft', 'review', 'approved', 'published'].map((status, idx) => (
                  <div key={status} className="flex items-center">
                    {idx > 0 && <div className="w-8 h-0.5 bg-slate-200 mr-2" />}
                    <div className="flex items-center gap-2">
                      <div className={`w-8 h-8 rounded-full flex items-center justify-center text-sm font-medium ${
                        (status === 'draft' && draftVersion?.status === 'draft') ||
                        (status === 'review' && draftVersion?.status === 'review') ||
                        (status === 'approved' && draftVersion?.status === 'approved') ||
                        (status === 'published' && !draftVersion)
                          ? 'bg-purple-500 text-white'
                          : 'bg-slate-200 text-slate-600'
                      }`}>{idx + 1}</div>
                      <span className="text-sm text-slate-600">
                        {status === 'draft' ? 'Entwurf' :
                         status === 'review' ? 'Pruefung' :
                         status === 'approved' ? 'Freigegeben' : 'Veroeffentlicht'}
                      </span>
                    </div>
                  </div>
                ))}
              </div>

              {/* Action Buttons */}
              <div className="flex items-center gap-2">
                {!draftVersion && (
                  <button
                    onClick={createNewDraft}
                    disabled={saving}
                    className="px-4 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700 disabled:opacity-50 text-sm font-medium"
                  >
                    Neue Version erstellen
                  </button>
                )}

                {draftVersion?.status === 'draft' && (
                  <>
                    <button
                      onClick={saveDraft}
                      disabled={saving}
                      className="px-4 py-2 bg-slate-600 text-white rounded-lg hover:bg-slate-700 disabled:opacity-50 text-sm font-medium"
                    >
                      {saving ? 'Speichern...' : 'Speichern'}
                    </button>
                    <button
                      onClick={submitForReview}
                      disabled={saving}
                      className="px-4 py-2 bg-blue-600 text-white rounded-lg hover:bg-blue-700 disabled:opacity-50 text-sm font-medium"
                    >
                      Zur Pruefung einreichen
                    </button>
                  </>
                )}

                {draftVersion?.status === 'review' && (
                  <>
                    <button
                      onClick={() => setShowApprovalModal('reject')}
                      disabled={saving}
                      className="px-4 py-2 bg-red-600 text-white rounded-lg hover:bg-red-700 disabled:opacity-50 text-sm font-medium"
                    >
                      Ablehnen
                    </button>
                    <button
                      onClick={() => setShowApprovalModal('approve')}
                      disabled={saving}
                      className="px-4 py-2 bg-green-600 text-white rounded-lg hover:bg-green-700 disabled:opacity-50 text-sm font-medium"
                    >
                      Freigeben
                    </button>
                  </>
                )}

                {draftVersion?.status === 'approved' && (
                  <button
                    onClick={publishVersion}
                    disabled={saving}
                    className="px-4 py-2 bg-emerald-600 text-white rounded-lg hover:bg-emerald-700 disabled:opacity-50 text-sm font-medium"
                  >
                    Jetzt veroeffentlichen
                  </button>
                )}

                {draftVersion?.status === 'rejected' && (
                  <div className="flex items-center gap-2">
                    <span className="text-sm text-red-600">Abgelehnt: {draftVersion.rejection_reason}</span>
                    <button
                      onClick={createNewDraft}
                      disabled={saving}
                      className="px-4 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700 disabled:opacity-50 text-sm font-medium"
                    >
                      Neu bearbeiten
                    </button>
                  </div>
                )}
              </div>
            </div>
          </div>

          {/* Rich Text Toolbar - only shown when editable */}
          {isEditable && (
            <div className="bg-white rounded-xl shadow-sm border p-3">
              <div className="flex items-center gap-1 flex-wrap">
                {/* Formatting */}
                <div className="flex items-center gap-1 border-r border-slate-200 pr-2 mr-2">
                  <button onClick={() => formatDoc('bold')} className="p-2 hover:bg-slate-100 rounded" title="Fett">
                    <span className="font-bold">B</span>
                  </button>
                  <button onClick={() => formatDoc('italic')} className="p-2 hover:bg-slate-100 rounded" title="Kursiv">
                    <span className="italic">I</span>
                  </button>
                  <button onClick={() => formatDoc('underline')} className="p-2 hover:bg-slate-100 rounded" title="Unterstrichen">
                    <span className="underline">U</span>
                  </button>
                </div>

                {/* Headings */}
                <div className="flex items-center gap-1 border-r border-slate-200 pr-2 mr-2">
                  <button onClick={() => formatBlock('h1')} className="p-2 hover:bg-slate-100 rounded text-sm" title="Ueberschrift 1">
                    H1
                  </button>
                  <button onClick={() => formatBlock('h2')} className="p-2 hover:bg-slate-100 rounded text-sm" title="Ueberschrift 2">
                    H2
                  </button>
                  <button onClick={() => formatBlock('h3')} className="p-2 hover:bg-slate-100 rounded text-sm" title="Ueberschrift 3">
                    H3
                  </button>
                  <button onClick={() => formatBlock('p')} className="p-2 hover:bg-slate-100 rounded text-sm" title="Absatz">
                    P
                  </button>
                </div>

                {/* Lists */}
                <div className="flex items-center gap-1 border-r border-slate-200 pr-2 mr-2">
                  <button onClick={() => formatDoc('insertUnorderedList')} className="p-2 hover:bg-slate-100 rounded" title="Aufzaehlung">
                    <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                      <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 6h16M4 12h16M4 18h16" />
                    </svg>
                  </button>
                  <button onClick={() => formatDoc('insertOrderedList')} className="p-2 hover:bg-slate-100 rounded" title="Nummerierung">
                    <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                      <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M7 20l4-16m2 16l4-16M6 9h14M4 15h14" />
                    </svg>
                  </button>
                </div>

                {/* Links */}
                <div className="flex items-center gap-1 border-r border-slate-200 pr-2 mr-2">
                  <button onClick={insertLink} className="p-2 hover:bg-slate-100 rounded" title="Link einfuegen">
                    <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                      <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M13.828 10.172a4 4 0 00-5.656 0l-4 4a4 4 0 105.656 5.656l1.102-1.101m-.758-4.899a4 4 0 005.656 0l4-4a4 4 0 00-5.656-5.656l-1.1 1.1" />
                    </svg>
                  </button>
                </div>

                {/* Word Upload */}
                <div className="flex items-center gap-1">
                  <input
                    type="file"
                    ref={fileInputRef}
                    onChange={handleWordUpload}
                    accept=".docx,.doc"
                    className="hidden"
                  />
                  <button
                    onClick={() => fileInputRef.current?.click()}
                    disabled={uploading}
                    className="px-3 py-2 bg-blue-50 text-blue-700 hover:bg-blue-100 rounded text-sm flex items-center gap-1"
                    title="Word-Dokument importieren"
                  >
                    <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                      <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 16v1a3 3 0 003 3h10a3 3 0 003-3v-1m-4-8l-4-4m0 0L8 8m4-4v12" />
                    </svg>
                    {uploading ? 'Importiere...' : 'Word importieren'}
                  </button>
                </div>
              </div>
            </div>
          )}

          {/* Split View Editor - Synchronized Scrolling */}
          <div className="grid grid-cols-2 gap-4">
            {/* Left: Current Published Version */}
            <div className="bg-white rounded-xl shadow-sm border overflow-hidden">
              <div className="bg-emerald-50 border-b border-emerald-200 px-4 py-3 flex items-center justify-between">
                <div>
                  <h3 className="font-semibold text-emerald-900">Veroeffentlichte Version</h3>
                  {currentVersion && (
                    <p className="text-sm text-emerald-700">v{currentVersion.version}</p>
                  )}
                </div>
                <span className="px-2 py-1 bg-emerald-100 text-emerald-700 rounded text-xs font-medium">
                  Nur Lesen
                </span>
              </div>
              <div className="p-4">
                {currentVersion ? (
                  <>
                    <input
                      type="text"
                      value={currentVersion.title}
                      disabled
                      className="w-full px-3 py-2 mb-4 bg-slate-50 border border-slate-200 rounded-lg text-slate-700"
                    />
                    <div
                      ref={leftPanelRef}
                      className="prose prose-sm max-w-none p-4 bg-slate-50 border border-slate-200 rounded-lg min-h-[500px] max-h-[500px] overflow-y-auto"
                      dangerouslySetInnerHTML={{ __html: currentVersion.content }}
                    />
                  </>
                ) : (
                  <div className="text-center py-12 text-slate-500">
                    Keine veroeffentlichte Version vorhanden
                  </div>
                )}
              </div>
            </div>

            {/* Right: Draft/Edit Version */}
            <div className="bg-white rounded-xl shadow-sm border overflow-hidden">
              <div className={`border-b px-4 py-3 flex items-center justify-between ${
                draftVersion?.status === 'draft' ? 'bg-yellow-50 border-yellow-200' :
                draftVersion?.status === 'review' ? 'bg-blue-50 border-blue-200' :
                draftVersion?.status === 'approved' ? 'bg-green-50 border-green-200' :
                'bg-slate-50 border-slate-200'
              }`}>
                <div>
                  <h3 className={`font-semibold ${
                    draftVersion?.status === 'draft' ? 'text-yellow-900' :
                    draftVersion?.status === 'review' ? 'text-blue-900' :
                    draftVersion?.status === 'approved' ? 'text-green-900' :
                    'text-slate-900'
                  }`}>
                    {draftVersion ? 'Aenderungsversion' : 'Neue Version'}
                  </h3>
                  {draftVersion && (
                    <p className={`text-sm ${
                      draftVersion.status === 'draft' ? 'text-yellow-700' :
                      draftVersion.status === 'review' ? 'text-blue-700' :
                      draftVersion.status === 'approved' ? 'text-green-700' :
                      'text-slate-700'
                    }`}>
                      v{draftVersion.version} - {STATUS_LABELS[draftVersion.status].label}
                    </p>
                  )}
                </div>
                {isEditable && (
                  <span className="px-2 py-1 bg-yellow-100 text-yellow-700 rounded text-xs font-medium">
                    Bearbeitbar
                  </span>
                )}
              </div>
              <div className="p-4">
                <input
                  type="text"
                  value={editedTitle}
                  onChange={(e) => setEditedTitle(e.target.value)}
                  disabled={!isEditable}
                  placeholder="Titel der Version..."
                  className={`w-full px-3 py-2 mb-4 border rounded-lg ${
                    isEditable ? 'border-slate-300 bg-white' : 'border-slate-200 bg-slate-50 text-slate-700'
                  }`}
                />

                {isEditable ? (
                  <div
                    ref={rightPanelRef}
                    className="min-h-[500px] max-h-[500px] overflow-y-auto"
                  >
                    <div
                      ref={editorRef}
                      contentEditable
                      onInput={updateEditorContent}
                      onPaste={handlePaste}
                      className="prose prose-sm max-w-none p-4 bg-white border border-slate-300 rounded-lg min-h-[500px] focus:outline-none focus:ring-2 focus:ring-purple-500 focus:border-transparent"
                      dangerouslySetInnerHTML={{ __html: editedContent }}
                      suppressContentEditableWarning
                    />
                  </div>
                ) : (
                  <div
                    ref={rightPanelRef}
                    className="prose prose-sm max-w-none p-4 bg-slate-50 border border-slate-200 rounded-lg min-h-[500px] max-h-[500px] overflow-y-auto"
                    dangerouslySetInnerHTML={{ __html: editedContent || draftVersion?.content || '' }}
                  />
                )}

                {/* Character count */}
                <div className="mt-2 text-right text-sm text-slate-500">
                  {(editorRef.current?.textContent || editedContent.replace(/<[^>]*>/g, '')).length} Zeichen
                </div>
              </div>
            </div>
          </div>

          {/* History Panel */}
          {showHistory && (
            <div className="bg-white rounded-xl shadow-sm border p-6">
              <h3 className="text-lg font-semibold text-slate-900 mb-4">Genehmigungsverlauf</h3>
              {approvalHistory.length > 0 ? (
                <div className="space-y-3">
                  {approvalHistory.map((item, idx) => (
                    <div key={idx} className="flex items-center gap-4 p-3 border border-slate-200 rounded-lg">
                      <span className={`px-2 py-1 rounded text-xs ${
                        item.action === 'approved' ? 'bg-green-100 text-green-700' :
                        item.action === 'rejected' ? 'bg-red-100 text-red-700' :
                        item.action === 'submitted' ? 'bg-blue-100 text-blue-700' :
                        'bg-slate-100 text-slate-700'
                      }`}>{item.action}</span>
                      <span className="text-sm text-slate-600">{item.approver || 'System'}</span>
                      {item.comment && (
                        <span className="text-sm text-slate-500 italic">&quot;{item.comment}&quot;</span>
                      )}
                      <span className="text-sm text-slate-400 ml-auto">
                        {new Date(item.created_at).toLocaleString('de-DE')}
                      </span>
                    </div>
                  ))}
                </div>
              ) : (
                <p className="text-slate-500">Keine Genehmigungshistorie vorhanden.</p>
              )}

              <h3 className="text-lg font-semibold text-slate-900 mt-6 mb-4">Alle Versionen</h3>
              <div className="space-y-3">
                {versions.map((v) => (
                  <div
                    key={v.id}
                    className={`p-4 border rounded-lg ${
                      v.id === draftVersion?.id ? 'border-purple-300 bg-purple-50' :
                      v.id === currentVersion?.id ? 'border-emerald-300 bg-emerald-50' :
                      'border-slate-200'
                    }`}
                  >
                    <div className="flex items-center justify-between">
                      <div className="flex items-center gap-3">
                        <span className="font-mono font-medium">v{v.version}</span>
                        <span className={`px-2 py-0.5 rounded text-xs ${STATUS_LABELS[v.status].color}`}>
                          {STATUS_LABELS[v.status].label}
                        </span>
                        <span className="text-sm text-slate-500">{v.title}</span>
                      </div>
                      <span className="text-sm text-slate-400">
                        {new Date(v.created_at).toLocaleDateString('de-DE')}
                      </span>
                    </div>
                  </div>
                ))}
              </div>
            </div>
          )}
        </>
      )}

      {/* Full Screen Compare View */}
      {showCompareView && (
        <div className="fixed inset-0 bg-slate-900 z-50 flex flex-col">
          {/* Header */}
          <div className="bg-slate-800 border-b border-slate-700 px-6 py-4 flex items-center justify-between">
            <div className="flex items-center gap-4">
              <h2 className="text-xl font-semibold text-white">Versionsvergleich</h2>
              <span className="text-slate-400">
                {currentVersion ? `v${currentVersion.version}` : 'Keine Version'}
                <span className="mx-2 text-slate-600">vs</span>
                {draftVersion ? `v${draftVersion.version}` : 'Neue Version'}
              </span>
            </div>
            <button
              onClick={() => setShowCompareView(false)}
              className="px-4 py-2 bg-slate-700 text-white rounded-lg hover:bg-slate-600"
            >
              Schliessen
            </button>
          </div>

          {/* Compare Panels */}
          <div className="flex-1 grid grid-cols-2 gap-1 bg-slate-700">
            {/* Left: Published */}
            <div className="bg-white flex flex-col">
              <div className="bg-emerald-100 border-b border-emerald-200 px-4 py-2">
                <span className="font-medium text-emerald-800">Veroeffentlichte Version</span>
                {currentVersion && (
                  <span className="ml-2 text-emerald-600">v{currentVersion.version}</span>
                )}
              </div>
              <div className="flex-1 overflow-y-auto p-6 prose prose-sm max-w-none">
                {currentVersion ? (
                  <div dangerouslySetInnerHTML={{ __html: currentVersion.content }} />
                ) : (
                  <p className="text-slate-500 text-center py-12">Keine veroeffentlichte Version</p>
                )}
              </div>
            </div>

            {/* Right: Draft */}
            <div className="bg-white flex flex-col">
              <div className={`border-b px-4 py-2 ${
                draftVersion?.status === 'draft' ? 'bg-yellow-100 border-yellow-200' :
                draftVersion?.status === 'review' ? 'bg-blue-100 border-blue-200' :
                draftVersion?.status === 'approved' ? 'bg-green-100 border-green-200' :
                'bg-slate-100 border-slate-200'
              }`}>
                <span className={`font-medium ${
                  draftVersion?.status === 'draft' ? 'text-yellow-800' :
                  draftVersion?.status === 'review' ? 'text-blue-800' :
                  draftVersion?.status === 'approved' ? 'text-green-800' :
                  'text-slate-800'
                }`}>
                  {draftVersion ? 'Aenderungsversion' : 'Neue Version'}
                </span>
                {draftVersion && (
                  <span className={`ml-2 ${
                    draftVersion.status === 'draft' ? 'text-yellow-600' :
                    draftVersion.status === 'review' ? 'text-blue-600' :
                    draftVersion.status === 'approved' ? 'text-green-600' :
                    'text-slate-600'
                  }`}>
                    v{draftVersion.version} - {STATUS_LABELS[draftVersion.status].label}
                  </span>
                )}
              </div>
              <div className="flex-1 overflow-y-auto p-6 prose prose-sm max-w-none">
                <div dangerouslySetInnerHTML={{ __html: editedContent || draftVersion?.content || '' }} />
              </div>
            </div>
          </div>

          {/* Footer with Actions */}
          <div className="bg-slate-800 border-t border-slate-700 px-6 py-4 flex items-center justify-end gap-3">
            {draftVersion?.status === 'draft' && (
              <>
                <button
                  onClick={() => { setShowCompareView(false); saveDraft() }}
                  className="px-4 py-2 bg-slate-600 text-white rounded-lg hover:bg-slate-500"
                >
                  Speichern
                </button>
                <button
                  onClick={() => { setShowCompareView(false); submitForReview() }}
                  className="px-4 py-2 bg-blue-600 text-white rounded-lg hover:bg-blue-500"
                >
                  Zur Pruefung einreichen
                </button>
              </>
            )}
            {draftVersion?.status === 'review' && (
              <>
                <button
                  onClick={() => { setShowCompareView(false); setShowApprovalModal('reject') }}
                  className="px-4 py-2 bg-red-600 text-white rounded-lg hover:bg-red-500"
                >
                  Ablehnen
                </button>
                <button
                  onClick={() => { setShowCompareView(false); setShowApprovalModal('approve') }}
                  className="px-4 py-2 bg-green-600 text-white rounded-lg hover:bg-green-500"
                >
                  Freigeben
                </button>
              </>
            )}
            {draftVersion?.status === 'approved' && (
              <button
                onClick={() => { setShowCompareView(false); publishVersion() }}
                className="px-4 py-2 bg-emerald-600 text-white rounded-lg hover:bg-emerald-500"
              >
                Veroeffentlichen
              </button>
            )}
          </div>
        </div>
      )}

      {/* Approval Modal */}
      {showApprovalModal && (
        <div className="fixed inset-0 bg-black/50 flex items-center justify-center z-50">
          <div className="bg-white rounded-xl shadow-xl p-6 w-full max-w-md">
            <h3 className="text-lg font-semibold text-slate-900 mb-4">
              {showApprovalModal === 'approve' ? 'Version freigeben' : 'Version ablehnen'}
            </h3>
            <textarea
              value={approvalComment}
              onChange={(e) => setApprovalComment(e.target.value)}
              placeholder={showApprovalModal === 'approve' ? 'Kommentar (optional)...' : 'Ablehnungsgrund...'}
              className="w-full px-3 py-2 border border-slate-300 rounded-lg min-h-[100px] mb-4"
              required={showApprovalModal === 'reject'}
            />
            <div className="flex justify-end gap-3">
              <button
                onClick={() => {
                  setShowApprovalModal(null)
                  setApprovalComment('')
                }}
                className="px-4 py-2 text-slate-600 hover:text-slate-900"
              >
                Abbrechen
              </button>
              <button
                onClick={showApprovalModal === 'approve' ? approveVersion : rejectVersion}
                disabled={saving || (showApprovalModal === 'reject' && !approvalComment)}
                className={`px-4 py-2 text-white rounded-lg disabled:opacity-50 ${
                  showApprovalModal === 'approve'
                    ? 'bg-green-600 hover:bg-green-700'
                    : 'bg-red-600 hover:bg-red-700'
                }`}
              >
                {saving ? 'Wird verarbeitet...' : showApprovalModal === 'approve' ? 'Freigeben' : 'Ablehnen'}
              </button>
            </div>
          </div>
        </div>
      )}
    </div>
  )
}
