'use client'

import { useState, useEffect } from 'react'
import {
  DATA_SUBJECT_CATEGORY_META,
  PERSONAL_DATA_CATEGORY_META,
  LEGAL_BASIS_META,
  TRANSFER_MECHANISM_META,
  ART9_CATEGORIES,
  BUSINESS_FUNCTION_LABELS,
  STATUS_LABELS,
  STATUS_COLORS,
  PROTECTION_LEVEL_LABELS,
  DEPLOYMENT_LABELS,
} from '@/lib/sdk/vvt-types'
import type { VVTActivity, BusinessFunction } from '@/lib/sdk/vvt-types'
import { FormSection, FormField, MultiTextInput, CheckboxGrid } from './FormPrimitives'

export function TabEditor({
  activity, activities, onSave, onBack, onSelectActivity,
}: {
  activity: VVTActivity | null | undefined
  activities: VVTActivity[]
  onSave: (updated: VVTActivity) => void
  onBack: () => void
  onSelectActivity: (id: string) => void
}) {
  const [local, setLocal] = useState<VVTActivity | null>(null)
  const [showAdvanced, setShowAdvanced] = useState(false)

  useEffect(() => {
    setLocal(activity ? { ...activity } : null)
  }, [activity])

  if (!local) {
    return (
      <div className="space-y-4">
        <div className="bg-white rounded-xl border border-gray-200 p-8 text-center">
          <h3 className="text-lg font-semibold text-gray-900 mb-2">Keine Verarbeitung ausgewaehlt</h3>
          <p className="text-gray-500 mb-4">Waehlen Sie eine Verarbeitung aus dem Verzeichnis oder erstellen Sie eine neue.</p>
          <button onClick={onBack} className="px-4 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700">
            Zum Verzeichnis
          </button>
        </div>
        {activities.length > 0 && (
          <div className="bg-white rounded-xl border border-gray-200 p-4">
            <h4 className="font-medium text-gray-700 mb-3">Verarbeitungen zum Bearbeiten:</h4>
            <div className="space-y-1">
              {activities.map(a => (
                <button
                  key={a.id}
                  onClick={() => onSelectActivity(a.id)}
                  className="w-full text-left px-3 py-2 rounded-lg hover:bg-purple-50 text-sm flex items-center justify-between"
                >
                  <span><span className="font-mono text-gray-400 mr-2">{a.vvtId}</span>{a.name || '(Ohne Namen)'}</span>
                  <span className={`px-2 py-0.5 text-xs rounded-full ${STATUS_COLORS[a.status]}`}>{STATUS_LABELS[a.status]}</span>
                </button>
              ))}
            </div>
          </div>
        )}
      </div>
    )
  }

  const update = (patch: Partial<VVTActivity>) => setLocal(prev => prev ? { ...prev, ...patch } : prev)

  const handleSave = () => {
    if (local) onSave(local)
  }

  return (
    <div className="space-y-4">
      {/* Header */}
      <div className="flex items-center justify-between">
        <div className="flex items-center gap-3">
          <button onClick={onBack} className="p-2 hover:bg-gray-100 rounded-lg">
            <svg className="w-5 h-5 text-gray-500" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10 19l-7-7m0 0l7-7m-7 7h18" />
            </svg>
          </button>
          <div>
            <span className="text-sm font-mono text-gray-400">{local.vvtId}</span>
            <h2 className="text-lg font-bold text-gray-900">{local.name || 'Neue Verarbeitung'}</h2>
          </div>
        </div>
        <div className="flex items-center gap-2">
          <select
            value={local.status}
            onChange={(e) => update({ status: e.target.value as VVTActivity['status'] })}
            className="px-3 py-1.5 border border-gray-300 rounded-lg text-sm"
          >
            <option value="DRAFT">Entwurf</option>
            <option value="REVIEW">In Pruefung</option>
            <option value="APPROVED">Genehmigt</option>
            <option value="ARCHIVED">Archiviert</option>
          </select>
          <button onClick={handleSave} className="px-4 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700 text-sm">
            Speichern
          </button>
        </div>
      </div>

      {/* Form */}
      <div className="bg-white rounded-xl border border-gray-200 divide-y divide-gray-100">
        {/* Bezeichnung + Beschreibung */}
        <FormSection title="Grunddaten">
          <FormField label="Bezeichnung *">
            <input type="text" value={local.name} onChange={(e) => update({ name: e.target.value })}
              className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 focus:border-transparent"
              placeholder="z.B. Mitarbeiterverwaltung" />
          </FormField>
          <FormField label="Beschreibung">
            <textarea value={local.description} onChange={(e) => update({ description: e.target.value })}
              rows={2} className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 focus:border-transparent"
              placeholder="Kurze Beschreibung der Verarbeitung" />
          </FormField>
          <div className="grid grid-cols-2 gap-4">
            <FormField label="Verantwortlich">
              <input type="text" value={local.responsible} onChange={(e) => update({ responsible: e.target.value })}
                className="w-full px-3 py-2 border border-gray-300 rounded-lg" placeholder="z.B. HR-Abteilung" />
            </FormField>
            <FormField label="Geschaeftsbereich">
              <select value={local.businessFunction} onChange={(e) => update({ businessFunction: e.target.value as BusinessFunction })}
                className="w-full px-3 py-2 border border-gray-300 rounded-lg">
                {Object.entries(BUSINESS_FUNCTION_LABELS).map(([k, v]) => (
                  <option key={k} value={k}>{v}</option>
                ))}
              </select>
            </FormField>
          </div>
        </FormSection>

        {/* Zwecke */}
        <FormSection title="Zwecke der Verarbeitung *">
          <MultiTextInput
            values={local.purposes}
            onChange={(purposes) => update({ purposes })}
            placeholder="Zweck eingeben und Enter druecken"
          />
        </FormSection>

        {/* Rechtsgrundlagen */}
        <FormSection title="Rechtsgrundlagen *">
          <div className="space-y-2">
            {local.legalBases.map((lb, i) => (
              <div key={i} className="flex items-center gap-2">
                <select
                  value={lb.type}
                  onChange={(e) => {
                    const copy = [...local.legalBases]
                    copy[i] = { ...copy[i], type: e.target.value }
                    update({ legalBases: copy })
                  }}
                  className="flex-1 px-3 py-2 border border-gray-300 rounded-lg text-sm"
                >
                  <option value="">-- Rechtsgrundlage waehlen --</option>
                  {Object.entries(LEGAL_BASIS_META).map(([k, v]) => (
                    <option key={k} value={k}>{v.label.de} ({v.article})</option>
                  ))}
                </select>
                <input
                  type="text"
                  value={lb.reference || ''}
                  onChange={(e) => {
                    const copy = [...local.legalBases]
                    copy[i] = { ...copy[i], reference: e.target.value }
                    update({ legalBases: copy })
                  }}
                  className="w-48 px-3 py-2 border border-gray-300 rounded-lg text-sm"
                  placeholder="Referenz"
                />
                <button onClick={() => update({ legalBases: local.legalBases.filter((_, j) => j !== i) })}
                  className="p-2 text-gray-400 hover:text-red-500">
                  <svg className="w-4 h-4" 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>
            ))}
            <button onClick={() => update({ legalBases: [...local.legalBases, { type: '', description: '', reference: '' }] })}
              className="text-sm text-purple-600 hover:text-purple-700">
              + Rechtsgrundlage hinzufuegen
            </button>
          </div>
        </FormSection>

        {/* Betroffenenkategorien */}
        <FormSection title="Betroffenenkategorien *">
          <CheckboxGrid
            options={Object.entries(DATA_SUBJECT_CATEGORY_META).map(([k, v]) => ({ value: k, label: v.de }))}
            selected={local.dataSubjectCategories}
            onChange={(dataSubjectCategories) => update({ dataSubjectCategories })}
          />
        </FormSection>

        {/* Datenkategorien */}
        <FormSection title="Datenkategorien *">
          <CheckboxGrid
            options={Object.entries(PERSONAL_DATA_CATEGORY_META).map(([k, v]) => ({
              value: k,
              label: v.label.de,
              highlight: v.isSpecial,
            }))}
            selected={local.personalDataCategories}
            onChange={(personalDataCategories) => update({ personalDataCategories })}
          />
          {local.personalDataCategories.some(c => ART9_CATEGORIES.includes(c)) && (
            <div className="mt-2 p-3 bg-red-50 border border-red-200 rounded-lg text-sm text-red-700">
              <strong>Hinweis:</strong> Sie verarbeiten besondere Datenkategorien nach Art. 9 DSGVO. Stellen Sie sicher, dass eine Art.-9-Rechtsgrundlage vorliegt.
            </div>
          )}
        </FormSection>

        {/* Empfaenger */}
        <FormSection title="Empfaengerkategorien">
          <div className="space-y-2">
            {local.recipientCategories.map((rc, i) => (
              <div key={i} className="flex items-center gap-2">
                <select
                  value={rc.type}
                  onChange={(e) => {
                    const copy = [...local.recipientCategories]
                    copy[i] = { ...copy[i], type: e.target.value }
                    update({ recipientCategories: copy })
                  }}
                  className="w-40 px-3 py-2 border border-gray-300 rounded-lg text-sm"
                >
                  <option value="INTERNAL">Intern</option>
                  <option value="PROCESSOR">Auftragsverarbeiter</option>
                  <option value="CONTROLLER">Verantwortlicher</option>
                  <option value="AUTHORITY">Behoerde</option>
                  <option value="GROUP_COMPANY">Konzern</option>
                  <option value="OTHER">Sonstige</option>
                </select>
                <input type="text" value={rc.name}
                  onChange={(e) => {
                    const copy = [...local.recipientCategories]
                    copy[i] = { ...copy[i], name: e.target.value }
                    update({ recipientCategories: copy })
                  }}
                  className="flex-1 px-3 py-2 border border-gray-300 rounded-lg text-sm" placeholder="Name des Empfaengers" />
                <button onClick={() => update({ recipientCategories: local.recipientCategories.filter((_, j) => j !== i) })}
                  className="p-2 text-gray-400 hover:text-red-500">
                  <svg className="w-4 h-4" 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>
            ))}
            <button onClick={() => update({ recipientCategories: [...local.recipientCategories, { type: 'INTERNAL', name: '' }] })}
              className="text-sm text-purple-600 hover:text-purple-700">
              + Empfaenger hinzufuegen
            </button>
          </div>
        </FormSection>

        {/* Drittlandtransfers */}
        <FormSection title="Drittlandtransfers">
          <div className="space-y-2">
            {local.thirdCountryTransfers.map((tc, i) => (
              <div key={i} className="flex items-center gap-2 flex-wrap">
                <input type="text" value={tc.country}
                  onChange={(e) => {
                    const copy = [...local.thirdCountryTransfers]
                    copy[i] = { ...copy[i], country: e.target.value }
                    update({ thirdCountryTransfers: copy })
                  }}
                  className="w-20 px-3 py-2 border border-gray-300 rounded-lg text-sm" placeholder="Land" />
                <input type="text" value={tc.recipient}
                  onChange={(e) => {
                    const copy = [...local.thirdCountryTransfers]
                    copy[i] = { ...copy[i], recipient: e.target.value }
                    update({ thirdCountryTransfers: copy })
                  }}
                  className="flex-1 px-3 py-2 border border-gray-300 rounded-lg text-sm" placeholder="Empfaenger" />
                <select value={tc.transferMechanism}
                  onChange={(e) => {
                    const copy = [...local.thirdCountryTransfers]
                    copy[i] = { ...copy[i], transferMechanism: e.target.value }
                    update({ thirdCountryTransfers: copy })
                  }}
                  className="w-56 px-3 py-2 border border-gray-300 rounded-lg text-sm">
                  <option value="">-- Mechanismus --</option>
                  {Object.entries(TRANSFER_MECHANISM_META).map(([k, v]) => (
                    <option key={k} value={k}>{v.de}</option>
                  ))}
                </select>
                <button onClick={() => update({ thirdCountryTransfers: local.thirdCountryTransfers.filter((_, j) => j !== i) })}
                  className="p-2 text-gray-400 hover:text-red-500">
                  <svg className="w-4 h-4" 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>
            ))}
            <button onClick={() => update({ thirdCountryTransfers: [...local.thirdCountryTransfers, { country: '', recipient: '', transferMechanism: '' }] })}
              className="text-sm text-purple-600 hover:text-purple-700">
              + Drittlandtransfer hinzufuegen
            </button>
          </div>
        </FormSection>

        {/* Aufbewahrungsfristen */}
        <FormSection title="Aufbewahrungsfristen *">
          <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
            <FormField label="Dauer">
              <div className="flex gap-2">
                <input type="number" value={local.retentionPeriod.duration || ''}
                  onChange={(e) => update({ retentionPeriod: { ...local.retentionPeriod, duration: parseInt(e.target.value) || undefined } })}
                  className="w-20 px-3 py-2 border border-gray-300 rounded-lg" placeholder="z.B. 10" />
                <select value={local.retentionPeriod.durationUnit || 'YEARS'}
                  onChange={(e) => update({ retentionPeriod: { ...local.retentionPeriod, durationUnit: e.target.value } })}
                  className="px-3 py-2 border border-gray-300 rounded-lg">
                  <option value="DAYS">Tage</option>
                  <option value="MONTHS">Monate</option>
                  <option value="YEARS">Jahre</option>
                </select>
              </div>
            </FormField>
            <FormField label="Rechtsgrundlage">
              <input type="text" value={local.retentionPeriod.legalBasis || ''}
                onChange={(e) => update({ retentionPeriod: { ...local.retentionPeriod, legalBasis: e.target.value } })}
                className="w-full px-3 py-2 border border-gray-300 rounded-lg" placeholder="z.B. HGB § 257" />
            </FormField>
            <FormField label="Loeschverfahren">
              <input type="text" value={local.retentionPeriod.deletionProcedure || ''}
                onChange={(e) => update({ retentionPeriod: { ...local.retentionPeriod, deletionProcedure: e.target.value } })}
                className="w-full px-3 py-2 border border-gray-300 rounded-lg" placeholder="z.B. Automatische Loeschung" />
            </FormField>
          </div>
          <FormField label="Beschreibung">
            <input type="text" value={local.retentionPeriod.description}
              onChange={(e) => update({ retentionPeriod: { ...local.retentionPeriod, description: e.target.value } })}
              className="w-full px-3 py-2 border border-gray-300 rounded-lg" placeholder="Freitextbeschreibung der Aufbewahrungsfrist" />
          </FormField>
        </FormSection>

        {/* TOM-Beschreibung */}
        <FormSection title="TOM-Beschreibung (Art. 32)">
          <textarea value={local.tomDescription} onChange={(e) => update({ tomDescription: e.target.value })}
            rows={3} className="w-full px-3 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 focus:border-transparent"
            placeholder="Beschreiben Sie die technischen und organisatorischen Massnahmen zum Schutz der Daten" />
        </FormSection>

        {/* Advanced (collapsible) */}
        <div className="p-4">
          <button
            onClick={() => setShowAdvanced(!showAdvanced)}
            className="flex items-center gap-2 text-sm text-gray-600 hover:text-gray-900"
          >
            <svg className={`w-4 h-4 transition-transform ${showAdvanced ? 'rotate-90' : ''}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
            </svg>
            Generator-Felder (Schutzniveau, Systeme, DSFA)
          </button>

          {showAdvanced && (
            <div className="mt-4 space-y-4">
              <div className="grid grid-cols-3 gap-4">
                <FormField label="Schutzniveau">
                  <select value={local.protectionLevel} onChange={(e) => update({ protectionLevel: e.target.value as VVTActivity['protectionLevel'] })}
                    className="w-full px-3 py-2 border border-gray-300 rounded-lg">
                    {Object.entries(PROTECTION_LEVEL_LABELS).map(([k, v]) => (
                      <option key={k} value={k}>{v}</option>
                    ))}
                  </select>
                </FormField>
                <FormField label="Deployment">
                  <select value={local.deploymentModel} onChange={(e) => update({ deploymentModel: e.target.value as VVTActivity['deploymentModel'] })}
                    className="w-full px-3 py-2 border border-gray-300 rounded-lg">
                    {Object.entries(DEPLOYMENT_LABELS).map(([k, v]) => (
                      <option key={k} value={k}>{v}</option>
                    ))}
                  </select>
                </FormField>
                <FormField label="DSFA erforderlich">
                  <label className="flex items-center gap-2 mt-2">
                    <input type="checkbox" checked={local.dpiaRequired}
                      onChange={(e) => update({ dpiaRequired: e.target.checked })}
                      className="w-4 h-4 text-purple-600 rounded" />
                    <span className="text-sm text-gray-700">Ja, DSFA nach Art. 35 DSGVO erforderlich</span>
                  </label>
                </FormField>
              </div>
            </div>
          )}
        </div>
      </div>

      {/* Save button at bottom */}
      <div className="flex items-center justify-end gap-3">
        <button onClick={onBack} className="px-4 py-2 text-gray-600 hover:bg-gray-100 rounded-lg">
          Zurueck zum Verzeichnis
        </button>
        <button onClick={handleSave} className="px-6 py-2 bg-purple-600 text-white rounded-lg hover:bg-purple-700">
          Speichern
        </button>
      </div>
    </div>
  )
}