'use client'

import { useState } from 'react'
import { CompanyProfile } from '@/lib/sdk/types'
import { AISystem, AISystemTemplate } from './types'
import { AI_SYSTEM_TEMPLATES } from './ai-system-data'

export function StepAISystems({
  data,
  onChange,
}: {
  data: Partial<CompanyProfile> & { aiSystems?: AISystem[] }
  onChange: (updates: Record<string, unknown>) => void
}) {
  const aiSystems: AISystem[] = (data as any).aiSystems || []
  const [expandedSystem, setExpandedSystem] = useState<string | null>(null)
  const [collapsedCategories, setCollapsedCategories] = useState<Set<string>>(new Set())

  const activeIds = new Set(aiSystems.map(a => a.id))

  const toggleTemplateSystem = (template: AISystemTemplate) => {
    if (activeIds.has(template.id)) {
      onChange({ aiSystems: aiSystems.filter(a => a.id !== template.id) })
      if (expandedSystem === template.id) setExpandedSystem(null)
    } else {
      const newSystem: AISystem = {
        id: template.id, name: template.name, vendor: template.vendor,
        purpose: template.typicalPurposes.join(', '), purposes: [],
        processes_personal_data: template.processes_personal_data_likely, isCustom: false,
      }
      onChange({ aiSystems: [...aiSystems, newSystem] })
      setExpandedSystem(template.id)
    }
  }

  const updateAISystem = (id: string, updates: Partial<AISystem>) => {
    onChange({ aiSystems: aiSystems.map(a => a.id === id ? { ...a, ...updates } : a) })
  }

  const togglePurpose = (systemId: string, purpose: string) => {
    const system = aiSystems.find(a => a.id === systemId)
    if (!system) return
    const purposes = system.purposes || []
    const updated = purposes.includes(purpose) ? purposes.filter(p => p !== purpose) : [...purposes, purpose]
    updateAISystem(systemId, { purposes: updated, purpose: updated.join(', ') })
  }

  const addCustomSystem = () => {
    const id = `custom_ai_${Date.now()}`
    onChange({ aiSystems: [...aiSystems, { id, name: '', vendor: '', purpose: '', processes_personal_data: false, isCustom: true }] })
    setExpandedSystem(id)
  }

  const removeSystem = (id: string) => {
    onChange({ aiSystems: aiSystems.filter(a => a.id !== id) })
    if (expandedSystem === id) setExpandedSystem(null)
  }

  const toggleCategoryCollapse = (category: string) => {
    setCollapsedCategories(prev => { const next = new Set(prev); if (next.has(category)) next.delete(category); else next.add(category); return next })
  }

  const categoryActiveCount = (systems: AISystemTemplate[]) => systems.filter(s => activeIds.has(s.id)).length

  return (
    <div className="space-y-6">
      <div>
        <h3 className="text-sm font-medium text-gray-700 mb-1">KI-Systeme im Einsatz</h3>
        <p className="text-xs text-gray-500 mb-4">
          Waehlen Sie die KI-Systeme aus, die in Ihrem Unternehmen eingesetzt werden. Dies dient der Erfassung fuer den EU AI Act und die DSGVO-Dokumentation.
        </p>
      </div>

      <div className="space-y-4">
        {AI_SYSTEM_TEMPLATES.map(group => {
          const isCollapsed = collapsedCategories.has(group.category)
          const activeCount = categoryActiveCount(group.systems)

          return (
            <div key={group.category} className="border border-gray-200 rounded-lg overflow-hidden">
              <button type="button" onClick={() => toggleCategoryCollapse(group.category)} className="w-full flex items-center gap-3 px-4 py-3 bg-gray-50 hover:bg-gray-100 transition-colors text-left">
                <span className="text-base">{group.icon}</span>
                <span className="text-sm font-medium text-gray-900 flex-1">{group.category}</span>
                {activeCount > 0 && <span className="text-xs bg-purple-100 text-purple-700 px-2 py-0.5 rounded-full">{activeCount} aktiv</span>}
                <svg className={`w-4 h-4 text-gray-400 transition-transform ${isCollapsed ? '' : 'rotate-180'}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
                  <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
                </svg>
              </button>

              {!isCollapsed && (
                <div className="p-3 space-y-2">
                  {group.systems.map(template => {
                    const isActive = activeIds.has(template.id)
                    const system = aiSystems.find(a => a.id === template.id)
                    const isExpanded = expandedSystem === template.id

                    return (
                      <div key={template.id}>
                        <div
                          className={`flex items-center gap-3 p-3 rounded-lg border-2 cursor-pointer transition-all ${isActive ? 'border-purple-500 bg-purple-50' : 'border-gray-100 hover:border-purple-300'}`}
                          onClick={() => { if (!isActive) { toggleTemplateSystem(template) } else { setExpandedSystem(isExpanded ? null : template.id) } }}
                        >
                          <input type="checkbox" checked={isActive} onChange={e => { e.stopPropagation(); toggleTemplateSystem(template) }} className="w-4 h-4 text-purple-600 rounded focus:ring-purple-500 flex-shrink-0" />
                          <div className="flex-1 min-w-0">
                            <div className="text-sm font-medium text-gray-900">{template.name}</div>
                            <p className="text-xs text-gray-500">{template.vendor}</p>
                          </div>
                          {isActive && (
                            <svg className={`w-4 h-4 text-gray-400 transition-transform ${isExpanded ? 'rotate-180' : ''}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
                              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
                            </svg>
                          )}
                        </div>

                        {isActive && isExpanded && system && (
                          <div className="ml-4 mt-2 p-4 bg-gray-50 rounded-lg border border-gray-200 space-y-4">
                            <div>
                              <label className="block text-xs font-medium text-gray-600 mb-2">Einsatzzweck</label>
                              <div className="flex flex-wrap gap-2">
                                {template.typicalPurposes.map(purpose => (
                                  <button key={purpose} type="button" onClick={() => togglePurpose(template.id, purpose)}
                                    className={`px-3 py-1.5 text-xs rounded-full border transition-all ${(system.purposes || []).includes(purpose) ? 'bg-purple-100 border-purple-300 text-purple-700' : 'bg-white border-gray-200 text-gray-600 hover:border-purple-200'}`}>
                                    {purpose}
                                  </button>
                                ))}
                              </div>
                              <input type="text" value={system.notes || ''} onChange={e => updateAISystem(template.id, { notes: e.target.value })} placeholder="Weitere Einsatzzwecke / Anmerkungen..." className="mt-2 w-full px-3 py-2 border border-gray-300 rounded-lg text-sm focus:ring-2 focus:ring-purple-500 focus:border-transparent" />
                            </div>

                            {template.dataWarning && (
                              <div className={`flex items-start gap-2 px-3 py-2 rounded-lg ${template.dataWarning.includes('EU') || template.dataWarning.includes('Deutscher Anbieter') || template.dataWarning.includes('NICHT') ? 'bg-blue-50 border border-blue-200' : 'bg-amber-50 border border-amber-200'}`}>
                                <span className="text-sm mt-0.5">{template.dataWarning.includes('EU') || template.dataWarning.includes('Deutscher Anbieter') ? '\u2139\uFE0F' : '\u26A0\uFE0F'}</span>
                                <span className="text-xs text-gray-800">{template.dataWarning}</span>
                              </div>
                            )}

                            <label className="flex items-center gap-2 px-1 cursor-pointer">
                              <input type="checkbox" checked={system.processes_personal_data} onChange={e => updateAISystem(template.id, { processes_personal_data: e.target.checked })} className="w-4 h-4 text-purple-600 rounded focus:ring-purple-500" />
                              <span className="text-sm text-gray-700">Verarbeitet personenbezogene Daten</span>
                            </label>

                            <button type="button" onClick={() => removeSystem(template.id)} className="text-xs text-red-500 hover:text-red-700">KI-System entfernen</button>
                          </div>
                        )}
                      </div>
                    )
                  })}
                </div>
              )}
            </div>
          )
        })}
      </div>

      {aiSystems.filter(a => a.isCustom).map(system => (
        <div key={system.id} className="mt-2">
          <div className="flex items-center gap-3 p-3 rounded-lg border-2 border-purple-500 bg-purple-50 cursor-pointer" onClick={() => setExpandedSystem(expandedSystem === system.id ? null : system.id)}>
            <span className="w-4 h-4 flex items-center justify-center text-purple-600 flex-shrink-0 text-sm">+</span>
            <div className="flex-1 min-w-0">
              <span className="text-sm font-medium text-gray-900">{system.name || 'Neues KI-System'}</span>
              {system.vendor && <span className="text-xs text-gray-500 ml-2">({system.vendor})</span>}
            </div>
            <svg className={`w-4 h-4 text-gray-400 transition-transform ${expandedSystem === system.id ? 'rotate-180' : ''}`} fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 9l-7 7-7-7" />
            </svg>
          </div>
          {expandedSystem === system.id && (
            <div className="ml-4 mt-2 p-4 bg-gray-50 rounded-lg border border-gray-200 space-y-3">
              <div className="grid grid-cols-2 gap-3">
                <input type="text" value={system.name} onChange={e => updateAISystem(system.id, { name: e.target.value })} placeholder="Name (z.B. ChatGPT, Copilot)" className="px-3 py-2 border border-gray-300 rounded-lg text-sm focus:ring-2 focus:ring-purple-500 focus:border-transparent" />
                <input type="text" value={system.vendor} onChange={e => updateAISystem(system.id, { vendor: e.target.value })} placeholder="Anbieter (z.B. OpenAI, Microsoft)" className="px-3 py-2 border border-gray-300 rounded-lg text-sm focus:ring-2 focus:ring-purple-500 focus:border-transparent" />
              </div>
              <input type="text" value={system.purpose} onChange={e => updateAISystem(system.id, { purpose: e.target.value })} placeholder="Einsatzzweck (z.B. Kundensupport, Code-Assistenz)" className="w-full px-3 py-2 border border-gray-300 rounded-lg text-sm focus:ring-2 focus:ring-purple-500 focus:border-transparent" />
              <label className="flex items-center gap-2 px-1 cursor-pointer">
                <input type="checkbox" checked={system.processes_personal_data} onChange={e => updateAISystem(system.id, { processes_personal_data: e.target.checked })} className="w-4 h-4 text-purple-600 rounded focus:ring-purple-500" />
                <span className="text-sm text-gray-700">Verarbeitet personenbezogene Daten</span>
              </label>
              <button type="button" onClick={() => removeSystem(system.id)} className="text-xs text-red-500 hover:text-red-700">KI-System entfernen</button>
            </div>
          )}
        </div>
      ))}

      <button type="button" onClick={addCustomSystem} className="w-full mt-3 px-3 py-2 text-sm text-purple-700 bg-purple-50 border-2 border-dashed border-purple-200 rounded-lg hover:bg-purple-100 hover:border-purple-300 transition-colors">
        + Eigenes KI-System hinzufuegen
      </button>

      <div className="mt-6 p-4 bg-blue-50 border border-blue-200 rounded-lg">
        <div className="flex items-start gap-3">
          <span className="text-lg">{'\u2139\uFE0F'}</span>
          <div>
            <h4 className="text-sm font-medium text-blue-900 mb-1">AI Act Risikoeinstufung</h4>
            <p className="text-xs text-blue-800 mb-3">
              Die detaillierte Risikoeinstufung Ihrer KI-Systeme nach EU AI Act (verboten / hochriskant / begrenzt / minimal) erfolgt automatisch im AI-Act-Modul.
            </p>
            <a href="/sdk/ai-act" className="inline-flex items-center gap-1 text-sm font-medium text-blue-700 hover:text-blue-900">
              Zum AI-Act-Modul
              <svg className="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 5l7 7-7 7" />
              </svg>
            </a>
          </div>
        </div>
      </div>
    </div>
  )
}