'use client'

/**
 * DraftingEngineWidget - Erweitert den ComplianceAdvisor um 4 Modi
 *
 * Mode-Indicator Pills: Explain / Ask / Draft / Validate
 * Document-Type Selector aus requiredDocuments der ScopeDecision
 * Feature-Flag enableDraftingEngine fuer schrittweises Rollout
 */

import { useState, useEffect, useRef, useCallback } from 'react'
import { useSDK } from '@/lib/sdk/context'
import { useDraftingEngine } from '@/lib/sdk/drafting-engine/use-drafting-engine'
import { DOCUMENT_TYPE_LABELS } from '@/lib/sdk/compliance-scope-types'
import type { AgentMode } from '@/lib/sdk/drafting-engine/types'
import type { ScopeDocumentType } from '@/lib/sdk/compliance-scope-types'
import { DraftEditor } from './DraftEditor'
import { ValidationReport } from './ValidationReport'

interface DraftingEngineWidgetProps {
  currentStep?: string
  enableDraftingEngine?: boolean
}

const MODE_CONFIG: Record<AgentMode, { label: string; color: string; activeColor: string; icon: string }> = {
  explain: { label: 'Explain', color: 'bg-gray-100 text-gray-600', activeColor: 'bg-purple-100 text-purple-700 ring-1 ring-purple-300', icon: 'M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z' },
  ask: { label: 'Ask', color: 'bg-gray-100 text-gray-600', activeColor: 'bg-amber-100 text-amber-700 ring-1 ring-amber-300', icon: 'M8.228 9c.549-1.165 2.03-2 3.772-2 2.21 0 4 1.343 4 3 0 1.4-1.278 2.575-3.006 2.907-.542.104-.994.54-.994 1.093m0 3h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z' },
  draft: { label: 'Draft', color: 'bg-gray-100 text-gray-600', activeColor: 'bg-blue-100 text-blue-700 ring-1 ring-blue-300', icon: 'M11 5H6a2 2 0 00-2 2v11a2 2 0 002 2h11a2 2 0 002-2v-5m-1.414-9.414a2 2 0 112.828 2.828L11.828 15H9v-2.828l8.586-8.586z' },
  validate: { label: 'Validate', color: 'bg-gray-100 text-gray-600', activeColor: 'bg-green-100 text-green-700 ring-1 ring-green-300', icon: 'M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z' },
}

const EXAMPLE_QUESTIONS: Record<AgentMode, string[]> = {
  explain: [
    'Was ist ein Verarbeitungsverzeichnis?',
    'Wann brauche ich eine DSFA?',
    'Was sind TOM nach Art. 32 DSGVO?',
  ],
  ask: [
    'Welche Luecken hat mein Compliance-Profil?',
    'Was fehlt noch fuer die Zertifizierung?',
    'Welche Dokumente muss ich noch erstellen?',
  ],
  draft: [
    'Erstelle einen VVT-Eintrag fuer unseren Hauptprozess',
    'Erstelle TOM fuer unsere Cloud-Infrastruktur',
    'Erstelle eine Datenschutzerklaerung',
  ],
  validate: [
    'Pruefe die Konsistenz meiner Dokumente',
    'Stimmen VVT und TOM ueberein?',
    'Gibt es Luecken bei den Loeschfristen?',
  ],
}

export function DraftingEngineWidget({
  currentStep = 'default',
  enableDraftingEngine = true,
}: DraftingEngineWidgetProps) {
  const { state } = useSDK()
  const engine = useDraftingEngine()
  const [isOpen, setIsOpen] = useState(false)
  const [isExpanded, setIsExpanded] = useState(false)
  const [inputValue, setInputValue] = useState('')
  const [showDraftEditor, setShowDraftEditor] = useState(false)
  const [showValidationReport, setShowValidationReport] = useState(false)
  const messagesEndRef = useRef<HTMLDivElement>(null)

  // Available document types from scope decision
  const availableDocumentTypes: ScopeDocumentType[] =
    state.complianceScope?.decision?.requiredDocuments
      ?.filter(d => d.required)
      .map(d => d.documentType as ScopeDocumentType) ?? ['vvt', 'tom', 'lf']

  // Auto-scroll
  useEffect(() => {
    messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' })
  }, [engine.messages])

  // Open draft editor when a new draft arrives
  useEffect(() => {
    if (engine.currentDraft) {
      setShowDraftEditor(true)
    }
  }, [engine.currentDraft])

  // Open validation report when new results arrive
  useEffect(() => {
    if (engine.validationResult) {
      setShowValidationReport(true)
    }
  }, [engine.validationResult])

  const handleSendMessage = useCallback(
    (content: string) => {
      if (!content.trim()) return
      setInputValue('')
      engine.sendMessage(content)
    },
    [engine]
  )

  const handleKeyDown = (e: React.KeyboardEvent) => {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault()
      handleSendMessage(inputValue)
    }
  }

  const exampleQuestions = EXAMPLE_QUESTIONS[engine.currentMode]

  if (!isOpen) {
    return (
      <button
        onClick={() => setIsOpen(true)}
        className="fixed bottom-6 right-[5.5rem] w-14 h-14 bg-indigo-600 hover:bg-indigo-700 text-white rounded-full shadow-lg flex items-center justify-center transition-all duration-200 hover:scale-110 z-50"
        aria-label="Drafting Engine oeffnen"
      >
        <svg className="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M11 5H6a2 2 0 00-2 2v11a2 2 0 002 2h11a2 2 0 002-2v-5m-1.414-9.414a2 2 0 112.828 2.828L11.828 15H9v-2.828l8.586-8.586z" />
        </svg>
      </button>
    )
  }

  // Draft Editor full-screen overlay
  if (showDraftEditor && engine.currentDraft) {
    return (
      <DraftEditor
        draft={engine.currentDraft}
        documentType={engine.activeDocumentType}
        constraintCheck={engine.constraintCheck}
        onAccept={() => {
          engine.acceptDraft()
          setShowDraftEditor(false)
        }}
        onValidate={() => {
          engine.validateDraft()
        }}
        onClose={() => setShowDraftEditor(false)}
        onRefine={(instruction: string) => {
          engine.requestDraft(instruction)
        }}
        validationResult={engine.validationResult}
        isTyping={engine.isTyping}
      />
    )
  }

  return (
    <div className={`fixed bottom-6 right-6 ${isExpanded ? 'w-[700px] h-[80vh]' : 'w-[420px] h-[560px]'} max-h-screen bg-white rounded-2xl shadow-2xl flex flex-col z-50 border border-gray-200 transition-all duration-200`}>
      {/* Header */}
      <div className="bg-gradient-to-r from-purple-600 to-indigo-600 text-white px-4 py-3 rounded-t-2xl flex items-center justify-between">
        <div className="flex items-center gap-2">
          <div className="w-8 h-8 bg-white/20 rounded-full flex items-center justify-center">
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M11 5H6a2 2 0 00-2 2v11a2 2 0 002 2h11a2 2 0 002-2v-5m-1.414-9.414a2 2 0 112.828 2.828L11.828 15H9v-2.828l8.586-8.586z" />
            </svg>
          </div>
          <div>
            <div className="font-semibold text-sm">Drafting Engine</div>
            <div className="text-xs text-white/80">Compliance-Dokumententwurf</div>
          </div>
        </div>
        <div className="flex items-center gap-1">
          <button
            onClick={() => setIsExpanded(!isExpanded)}
            className="text-white/80 hover:text-white transition-colors p-1"
            aria-label={isExpanded ? 'Verkleinern' : 'Vergroessern'}
          >
            <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
              {isExpanded ? (
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 9L4 4m0 0v4m0-4h4m6 6l5 5m0 0v-4m0 4h-4" />
              ) : (
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M4 8V4m0 0h4M4 4l5 5m11-1V4m0 0h-4m4 0l-5 5M4 16v4m0 0h4m-4 0l5-5m11 5v-4m0 4h-4m4 0l-5-5" />
              )}
            </svg>
          </button>
          <button
            onClick={() => {
              engine.clearMessages()
              setIsOpen(false)
            }}
            className="text-white/80 hover:text-white transition-colors p-1"
            aria-label="Schliessen"
          >
            <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>
      </div>

      {/* Mode Pills */}
      <div className="flex items-center gap-1 px-3 py-2 border-b border-gray-100 bg-white">
        {(Object.keys(MODE_CONFIG) as AgentMode[]).map((mode) => {
          const config = MODE_CONFIG[mode]
          const isActive = engine.currentMode === mode
          return (
            <button
              key={mode}
              onClick={() => engine.setMode(mode)}
              className={`flex items-center gap-1 px-2.5 py-1 rounded-full text-xs font-medium transition-all ${isActive ? config.activeColor : config.color} hover:opacity-80`}
            >
              <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d={config.icon} />
              </svg>
              {config.label}
            </button>
          )
        })}
      </div>

      {/* Document Type Selector (visible in draft/validate mode) */}
      {(engine.currentMode === 'draft' || engine.currentMode === 'validate') && (
        <div className="px-3 py-2 border-b border-gray-100 bg-gray-50/50">
          <div className="flex items-center gap-2">
            <span className="text-xs text-gray-500 shrink-0">Dokument:</span>
            <select
              value={engine.activeDocumentType || ''}
              onChange={(e) => engine.setDocumentType(e.target.value as ScopeDocumentType)}
              className="flex-1 text-xs border border-gray-200 rounded-md px-2 py-1 bg-white focus:outline-none focus:ring-1 focus:ring-purple-400"
            >
              <option value="">Dokumenttyp waehlen...</option>
              {availableDocumentTypes.map((dt) => (
                <option key={dt} value={dt}>
                  {DOCUMENT_TYPE_LABELS[dt] || dt}
                </option>
              ))}
            </select>
          </div>
        </div>
      )}

      {/* Error Banner */}
      {engine.error && (
        <div className="mx-3 mt-2 px-3 py-2 bg-red-50 border border-red-200 rounded-lg text-xs text-red-700 flex items-center justify-between">
          <span>{engine.error}</span>
          <button onClick={() => engine.clearMessages()} className="text-red-500 hover:text-red-700 ml-2">
            <svg className="w-3.5 h-3.5" 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>
      )}

      {/* Validation Report Inline */}
      {showValidationReport && engine.validationResult && (
        <div className="mx-3 mt-2 max-h-48 overflow-y-auto">
          <ValidationReport
            result={engine.validationResult}
            onClose={() => setShowValidationReport(false)}
            compact
          />
        </div>
      )}

      {/* Messages Area */}
      <div className="flex-1 overflow-y-auto p-4 space-y-3 bg-gray-50">
        {engine.messages.length === 0 ? (
          <div className="text-center py-6">
            <div className="w-14 h-14 bg-purple-100 rounded-full flex items-center justify-center mx-auto mb-3">
              <svg className="w-7 h-7 text-purple-600" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d={MODE_CONFIG[engine.currentMode].icon} />
              </svg>
            </div>
            <h3 className="text-sm font-medium text-gray-900 mb-1">
              {engine.currentMode === 'explain' && 'Fragen beantworten'}
              {engine.currentMode === 'ask' && 'Luecken erkennen'}
              {engine.currentMode === 'draft' && 'Dokumente entwerfen'}
              {engine.currentMode === 'validate' && 'Konsistenz pruefen'}
            </h3>
            <p className="text-xs text-gray-500 mb-4">
              {engine.currentMode === 'explain' && 'Stellen Sie Fragen zu DSGVO, AI Act und Compliance.'}
              {engine.currentMode === 'ask' && 'Identifiziert Luecken in Ihrem Compliance-Profil.'}
              {engine.currentMode === 'draft' && 'Erstellt strukturierte Compliance-Dokumente.'}
              {engine.currentMode === 'validate' && 'Prueft Cross-Dokument-Konsistenz.'}
            </p>

            <div className="text-left space-y-2">
              <p className="text-xs font-medium text-gray-700 mb-2">Beispiele:</p>
              {exampleQuestions.map((q, idx) => (
                <button
                  key={idx}
                  onClick={() => handleSendMessage(q)}
                  className="w-full text-left px-3 py-2 text-xs bg-white hover:bg-purple-50 border border-gray-200 rounded-lg transition-colors text-gray-700"
                >
                  {q}
                </button>
              ))}
            </div>

            {/* Quick Actions for Draft/Validate */}
            {engine.currentMode === 'draft' && engine.activeDocumentType && (
              <button
                onClick={() => engine.requestDraft()}
                className="mt-4 px-4 py-2 bg-blue-600 text-white text-xs font-medium rounded-lg hover:bg-blue-700 transition-colors"
              >
                Draft fuer {DOCUMENT_TYPE_LABELS[engine.activeDocumentType]?.split(' (')[0] || engine.activeDocumentType} erstellen
              </button>
            )}
            {engine.currentMode === 'validate' && (
              <button
                onClick={() => engine.validateDraft()}
                className="mt-4 px-4 py-2 bg-green-600 text-white text-xs font-medium rounded-lg hover:bg-green-700 transition-colors"
              >
                Validierung starten
              </button>
            )}
          </div>
        ) : (
          <>
            {engine.messages.map((message, idx) => (
              <div
                key={idx}
                className={`flex ${message.role === 'user' ? 'justify-end' : 'justify-start'}`}
              >
                <div
                  className={`max-w-[85%] rounded-lg px-3 py-2 ${
                    message.role === 'user'
                      ? 'bg-indigo-600 text-white'
                      : 'bg-white border border-gray-200 text-gray-800'
                  }`}
                >
                  <p className={`text-sm ${message.role === 'assistant' ? 'whitespace-pre-wrap' : ''}`}>
                    {message.content}
                  </p>

                  {/* Draft ready indicator */}
                  {message.metadata?.hasDraft && engine.currentDraft && (
                    <button
                      onClick={() => setShowDraftEditor(true)}
                      className="mt-2 flex items-center gap-1.5 px-3 py-1.5 bg-blue-50 border border-blue-200 rounded-md text-xs text-blue-700 hover:bg-blue-100 transition-colors"
                    >
                      <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M10 6H6a2 2 0 00-2 2v10a2 2 0 002 2h10a2 2 0 002-2v-4M14 4h6m0 0v6m0-6L10 14" />
                      </svg>
                      Im Editor oeffnen
                    </button>
                  )}

                  {/* Validation ready indicator */}
                  {message.metadata?.hasValidation && engine.validationResult && (
                    <button
                      onClick={() => setShowValidationReport(true)}
                      className="mt-2 flex items-center gap-1.5 px-3 py-1.5 bg-green-50 border border-green-200 rounded-md text-xs text-green-700 hover:bg-green-100 transition-colors"
                    >
                      <svg className="w-3.5 h-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                        <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M9 12l2 2 4-4m6 2a9 9 0 11-18 0 9 9 0 0118 0z" />
                      </svg>
                      Validierungsbericht anzeigen
                    </button>
                  )}
                </div>
              </div>
            ))}

            {engine.isTyping && (
              <div className="flex justify-start">
                <div className="bg-white border border-gray-200 rounded-lg px-3 py-2">
                  <div className="flex space-x-1">
                    <div className="w-2 h-2 bg-gray-400 rounded-full animate-bounce" />
                    <div className="w-2 h-2 bg-gray-400 rounded-full animate-bounce" style={{ animationDelay: '0.1s' }} />
                    <div className="w-2 h-2 bg-gray-400 rounded-full animate-bounce" style={{ animationDelay: '0.2s' }} />
                  </div>
                </div>
              </div>
            )}

            <div ref={messagesEndRef} />
          </>
        )}
      </div>

      {/* Input Area */}
      <div className="border-t border-gray-200 p-3 bg-white rounded-b-2xl">
        <div className="flex gap-2">
          <input
            type="text"
            value={inputValue}
            onChange={(e) => setInputValue(e.target.value)}
            onKeyDown={handleKeyDown}
            placeholder={
              engine.currentMode === 'draft'
                ? 'Anweisung fuer den Entwurf...'
                : engine.currentMode === 'validate'
                  ? 'Validierungsfrage...'
                  : 'Frage eingeben...'
            }
            disabled={engine.isTyping}
            className="flex-1 px-3 py-2 text-sm border border-gray-300 rounded-lg focus:outline-none focus:ring-2 focus:ring-purple-500 focus:border-transparent disabled:opacity-50"
          />
          {engine.isTyping ? (
            <button
              onClick={engine.stopGeneration}
              className="px-3 py-2 bg-red-500 text-white rounded-lg hover:bg-red-600 transition-colors"
              title="Generierung stoppen"
            >
              <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M6 6h12v12H6z" />
              </svg>
            </button>
          ) : (
            <button
              onClick={() => handleSendMessage(inputValue)}
              disabled={!inputValue.trim()}
              className="px-3 py-2 bg-indigo-600 text-white rounded-lg hover:bg-indigo-700 disabled:opacity-50 disabled:cursor-not-allowed transition-colors"
            >
              <svg className="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M12 19l9 2-9-18-9 18 9-2zm0 0v-8" />
              </svg>
            </button>
          )}
        </div>
      </div>
    </div>
  )
}