'use client'

import { useState, useMemo } from 'react'
import {
  useVendorCompliance,
  ReportType,
  ExportFormat,
  ProcessingActivity,
  Vendor,
} from '@/lib/sdk/vendor-compliance'

interface ExportConfig {
  reportType: ReportType
  format: ExportFormat
  scope: {
    vendorIds: string[]
    processingActivityIds: string[]
    includeFindings: boolean
    includeControls: boolean
    includeRiskAssessment: boolean
    dateRange?: {
      from: string
      to: string
    }
  }
}

const REPORT_TYPE_META: Record<
  ReportType,
  {
    title: string
    description: string
    icon: string
    formats: ExportFormat[]
    defaultFormat: ExportFormat
  }
> = {
  VVT_EXPORT: {
    title: 'Verarbeitungsverzeichnis (VVT)',
    description:
      'Vollständiges Verarbeitungsverzeichnis gemäß Art. 30 DSGVO mit allen Pflichtangaben',
    icon: '📋',
    formats: ['PDF', 'DOCX', 'XLSX'],
    defaultFormat: 'DOCX',
  },
  ROPA: {
    title: 'Records of Processing Activities (RoPA)',
    description:
      'Processor-Perspektive: Alle Verarbeitungen als Auftragsverarbeiter',
    icon: '📝',
    formats: ['PDF', 'DOCX', 'XLSX'],
    defaultFormat: 'DOCX',
  },
  VENDOR_AUDIT: {
    title: 'Vendor Audit Pack',
    description:
      'Vollständige Dokumentation eines Vendors inkl. Verträge, Findings und Risikobewertung',
    icon: '🔍',
    formats: ['PDF', 'DOCX'],
    defaultFormat: 'PDF',
  },
  MANAGEMENT_SUMMARY: {
    title: 'Management Summary',
    description:
      'Übersicht für die Geschäftsführung: Risiken, offene Findings, Compliance-Status',
    icon: '📊',
    formats: ['PDF', 'DOCX', 'XLSX'],
    defaultFormat: 'PDF',
  },
  DPIA_INPUT: {
    title: 'DSFA-Input',
    description:
      'Vorbereitete Daten für eine Datenschutz-Folgenabschätzung (DSFA/DPIA)',
    icon: '⚠️',
    formats: ['PDF', 'DOCX'],
    defaultFormat: 'DOCX',
  },
}

const FORMAT_META: Record<ExportFormat, { label: string; icon: string }> = {
  PDF: { label: 'PDF', icon: '📄' },
  DOCX: { label: 'Word (DOCX)', icon: '📝' },
  XLSX: { label: 'Excel (XLSX)', icon: '📊' },
  JSON: { label: 'JSON', icon: '🔧' },
}

export default function ReportsPage() {
  const {
    processingActivities,
    vendors,
    contracts,
    findings,
    riskAssessments,
    isLoading,
  } = useVendorCompliance()

  const [selectedReportType, setSelectedReportType] = useState<ReportType>('VVT_EXPORT')
  const [selectedFormat, setSelectedFormat] = useState<ExportFormat>('DOCX')
  const [selectedVendors, setSelectedVendors] = useState<string[]>([])
  const [selectedActivities, setSelectedActivities] = useState<string[]>([])
  const [includeFindings, setIncludeFindings] = useState(true)
  const [includeControls, setIncludeControls] = useState(true)
  const [includeRiskAssessment, setIncludeRiskAssessment] = useState(true)
  const [isGenerating, setIsGenerating] = useState(false)
  const [generatedReports, setGeneratedReports] = useState<
    { id: string; type: ReportType; format: ExportFormat; generatedAt: Date; filename: string }[]
  >([])

  const reportMeta = REPORT_TYPE_META[selectedReportType]

  // Update format when report type changes
  const handleReportTypeChange = (type: ReportType) => {
    setSelectedReportType(type)
    setSelectedFormat(REPORT_TYPE_META[type].defaultFormat)
    // Reset selections
    setSelectedVendors([])
    setSelectedActivities([])
  }

  // Calculate statistics
  const stats = useMemo(() => {
    const openFindings = findings.filter((f) => f.status === 'OPEN').length
    const criticalFindings = findings.filter(
      (f) => f.status === 'OPEN' && f.severity === 'CRITICAL'
    ).length
    const highRiskVendors = vendors.filter((v) => v.inherentRiskScore >= 70).length

    return {
      totalActivities: processingActivities.length,
      approvedActivities: processingActivities.filter((a) => a.status === 'APPROVED').length,
      totalVendors: vendors.length,
      activeVendors: vendors.filter((v) => v.status === 'ACTIVE').length,
      totalContracts: contracts.length,
      openFindings,
      criticalFindings,
      highRiskVendors,
    }
  }, [processingActivities, vendors, contracts, findings])

  // Handle export
  const handleExport = async () => {
    setIsGenerating(true)

    try {
      const config: ExportConfig = {
        reportType: selectedReportType,
        format: selectedFormat,
        scope: {
          vendorIds: selectedVendors,
          processingActivityIds: selectedActivities,
          includeFindings,
          includeControls,
          includeRiskAssessment,
        },
      }

      // Call API to generate report
      const response = await fetch('/api/sdk/v1/vendor-compliance/export', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(config),
      })

      if (!response.ok) {
        throw new Error('Export fehlgeschlagen')
      }

      const result = await response.json()

      // Add to generated reports
      setGeneratedReports((prev) => [
        {
          id: result.id,
          type: selectedReportType,
          format: selectedFormat,
          generatedAt: new Date(),
          filename: result.filename,
        },
        ...prev,
      ])

      // Download the file
      if (result.downloadUrl) {
        window.open(result.downloadUrl, '_blank')
      }
    } catch (error) {
      console.error('Export error:', error)
      // Show error notification
    } finally {
      setIsGenerating(false)
    }
  }

  // Toggle vendor selection
  const toggleVendor = (vendorId: string) => {
    setSelectedVendors((prev) =>
      prev.includes(vendorId)
        ? prev.filter((id) => id !== vendorId)
        : [...prev, vendorId]
    )
  }

  // Toggle activity selection
  const toggleActivity = (activityId: string) => {
    setSelectedActivities((prev) =>
      prev.includes(activityId)
        ? prev.filter((id) => id !== activityId)
        : [...prev, activityId]
    )
  }

  // Select all vendors
  const selectAllVendors = () => {
    setSelectedVendors(vendors.map((v) => v.id))
  }

  // Select all activities
  const selectAllActivities = () => {
    setSelectedActivities(processingActivities.map((a) => a.id))
  }

  if (isLoading) {
    return (
      <div className="flex items-center justify-center h-64">
        <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-blue-600"></div>
      </div>
    )
  }

  return (
    <div className="space-y-6">
      {/* Header */}
      <div>
        <h1 className="text-2xl font-bold text-gray-900 dark:text-white">
          Reports & Export
        </h1>
        <p className="mt-1 text-sm text-gray-500 dark:text-gray-400">
          Berichte erstellen und Daten exportieren
        </p>
      </div>

      {/* Quick Stats */}
      <div className="grid grid-cols-2 md:grid-cols-4 gap-4">
        <StatCard
          label="Verarbeitungen"
          value={stats.totalActivities}
          subtext={`${stats.approvedActivities} freigegeben`}
          color="blue"
        />
        <StatCard
          label="Vendors"
          value={stats.totalVendors}
          subtext={`${stats.highRiskVendors} hohes Risiko`}
          color="purple"
        />
        <StatCard
          label="Offene Findings"
          value={stats.openFindings}
          subtext={`${stats.criticalFindings} kritisch`}
          color={stats.criticalFindings > 0 ? 'red' : 'yellow'}
        />
        <StatCard
          label="Verträge"
          value={stats.totalContracts}
          subtext="dokumentiert"
          color="green"
        />
      </div>

      <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
        {/* Report Type Selection */}
        <div className="lg:col-span-2 space-y-6">
          {/* Report Type Cards */}
          <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
            <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700">
              <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                Report-Typ wählen
              </h2>
            </div>
            <div className="p-4 grid grid-cols-1 sm:grid-cols-2 gap-4">
              {(Object.entries(REPORT_TYPE_META) as [ReportType, typeof REPORT_TYPE_META[ReportType]][]).map(
                ([type, meta]) => (
                  <button
                    key={type}
                    onClick={() => handleReportTypeChange(type)}
                    className={`p-4 rounded-lg border-2 text-left transition-all ${
                      selectedReportType === type
                        ? 'border-blue-500 bg-blue-50 dark:bg-blue-900/20'
                        : 'border-gray-200 dark:border-gray-700 hover:border-gray-300 dark:hover:border-gray-600'
                    }`}
                  >
                    <div className="flex items-center gap-3">
                      <span className="text-2xl">{meta.icon}</span>
                      <div>
                        <h3 className="font-medium text-gray-900 dark:text-white">
                          {meta.title}
                        </h3>
                        <p className="text-sm text-gray-500 dark:text-gray-400 mt-1">
                          {meta.description}
                        </p>
                      </div>
                    </div>
                  </button>
                )
              )}
            </div>
          </div>

          {/* Scope Selection */}
          {(selectedReportType === 'VVT_EXPORT' || selectedReportType === 'ROPA' || selectedReportType === 'DPIA_INPUT') && (
            <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
              <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700 flex items-center justify-between">
                <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                  Verarbeitungen auswählen
                </h2>
                <button
                  onClick={selectAllActivities}
                  className="text-sm text-blue-600 hover:text-blue-800 dark:text-blue-400"
                >
                  Alle auswählen
                </button>
              </div>
              <div className="p-4 max-h-64 overflow-y-auto">
                {processingActivities.length === 0 ? (
                  <p className="text-sm text-gray-500 dark:text-gray-400 text-center py-4">
                    Keine Verarbeitungen vorhanden
                  </p>
                ) : (
                  <div className="space-y-2">
                    {processingActivities.map((activity) => (
                      <label
                        key={activity.id}
                        className="flex items-center gap-3 p-2 rounded hover:bg-gray-50 dark:hover:bg-gray-700/50 cursor-pointer"
                      >
                        <input
                          type="checkbox"
                          checked={selectedActivities.includes(activity.id)}
                          onChange={() => toggleActivity(activity.id)}
                          className="h-4 w-4 text-blue-600 rounded border-gray-300 focus:ring-blue-500"
                        />
                        <div className="flex-1 min-w-0">
                          <p className="text-sm font-medium text-gray-900 dark:text-white truncate">
                            {activity.name.de}
                          </p>
                          <p className="text-xs text-gray-500 dark:text-gray-400">
                            {activity.vvtId} · {activity.status}
                          </p>
                        </div>
                        <StatusBadge status={activity.status} />
                      </label>
                    ))}
                  </div>
                )}
              </div>
            </div>
          )}

          {selectedReportType === 'VENDOR_AUDIT' && (
            <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
              <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700 flex items-center justify-between">
                <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                  Vendor auswählen
                </h2>
                <button
                  onClick={selectAllVendors}
                  className="text-sm text-blue-600 hover:text-blue-800 dark:text-blue-400"
                >
                  Alle auswählen
                </button>
              </div>
              <div className="p-4 max-h-64 overflow-y-auto">
                {vendors.length === 0 ? (
                  <p className="text-sm text-gray-500 dark:text-gray-400 text-center py-4">
                    Keine Vendors vorhanden
                  </p>
                ) : (
                  <div className="space-y-2">
                    {vendors.map((vendor) => (
                      <label
                        key={vendor.id}
                        className="flex items-center gap-3 p-2 rounded hover:bg-gray-50 dark:hover:bg-gray-700/50 cursor-pointer"
                      >
                        <input
                          type="checkbox"
                          checked={selectedVendors.includes(vendor.id)}
                          onChange={() => toggleVendor(vendor.id)}
                          className="h-4 w-4 text-blue-600 rounded border-gray-300 focus:ring-blue-500"
                        />
                        <div className="flex-1 min-w-0">
                          <p className="text-sm font-medium text-gray-900 dark:text-white truncate">
                            {vendor.name}
                          </p>
                          <p className="text-xs text-gray-500 dark:text-gray-400">
                            {vendor.country} · {vendor.serviceCategory}
                          </p>
                        </div>
                        <RiskBadge score={vendor.inherentRiskScore} />
                      </label>
                    ))}
                  </div>
                )}
              </div>
            </div>
          )}

          {/* Include Options */}
          <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
            <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700">
              <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                Optionen
              </h2>
            </div>
            <div className="p-4 space-y-3">
              <label className="flex items-center gap-3 cursor-pointer">
                <input
                  type="checkbox"
                  checked={includeFindings}
                  onChange={(e) => setIncludeFindings(e.target.checked)}
                  className="h-4 w-4 text-blue-600 rounded border-gray-300 focus:ring-blue-500"
                />
                <div>
                  <p className="text-sm font-medium text-gray-900 dark:text-white">
                    Findings einbeziehen
                  </p>
                  <p className="text-xs text-gray-500 dark:text-gray-400">
                    Offene und behobene Vertragsprüfungs-Findings
                  </p>
                </div>
              </label>
              <label className="flex items-center gap-3 cursor-pointer">
                <input
                  type="checkbox"
                  checked={includeControls}
                  onChange={(e) => setIncludeControls(e.target.checked)}
                  className="h-4 w-4 text-blue-600 rounded border-gray-300 focus:ring-blue-500"
                />
                <div>
                  <p className="text-sm font-medium text-gray-900 dark:text-white">
                    Control-Status einbeziehen
                  </p>
                  <p className="text-xs text-gray-500 dark:text-gray-400">
                    Übersicht aller Kontrollen und deren Erfüllungsstatus
                  </p>
                </div>
              </label>
              <label className="flex items-center gap-3 cursor-pointer">
                <input
                  type="checkbox"
                  checked={includeRiskAssessment}
                  onChange={(e) => setIncludeRiskAssessment(e.target.checked)}
                  className="h-4 w-4 text-blue-600 rounded border-gray-300 focus:ring-blue-500"
                />
                <div>
                  <p className="text-sm font-medium text-gray-900 dark:text-white">
                    Risikobewertung einbeziehen
                  </p>
                  <p className="text-xs text-gray-500 dark:text-gray-400">
                    Inhärentes und Restrisiko mit Begründung
                  </p>
                </div>
              </label>
            </div>
          </div>
        </div>

        {/* Export Panel */}
        <div className="space-y-6">
          {/* Format & Export */}
          <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
            <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700">
              <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                Export
              </h2>
            </div>
            <div className="p-4 space-y-4">
              {/* Selected Report Info */}
              <div className="p-3 bg-gray-50 dark:bg-gray-700/50 rounded-lg">
                <div className="flex items-center gap-2 mb-2">
                  <span className="text-xl">{reportMeta.icon}</span>
                  <span className="font-medium text-gray-900 dark:text-white">
                    {reportMeta.title}
                  </span>
                </div>
                <p className="text-sm text-gray-500 dark:text-gray-400">
                  {reportMeta.description}
                </p>
              </div>

              {/* Format Selection */}
              <div>
                <label className="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-2">
                  Format
                </label>
                <div className="flex flex-wrap gap-2">
                  {reportMeta.formats.map((format) => (
                    <button
                      key={format}
                      onClick={() => setSelectedFormat(format)}
                      className={`px-3 py-2 rounded-lg text-sm font-medium transition-colors ${
                        selectedFormat === format
                          ? 'bg-blue-600 text-white'
                          : 'bg-gray-100 dark:bg-gray-700 text-gray-700 dark:text-gray-300 hover:bg-gray-200 dark:hover:bg-gray-600'
                      }`}
                    >
                      {FORMAT_META[format].icon} {FORMAT_META[format].label}
                    </button>
                  ))}
                </div>
              </div>

              {/* Scope Summary */}
              <div className="text-sm text-gray-500 dark:text-gray-400">
                <p>
                  {selectedReportType === 'VENDOR_AUDIT'
                    ? `${selectedVendors.length || 'Alle'} Vendor(s) ausgewählt`
                    : selectedReportType === 'MANAGEMENT_SUMMARY'
                    ? 'Gesamtübersicht'
                    : `${selectedActivities.length || 'Alle'} Verarbeitung(en) ausgewählt`}
                </p>
              </div>

              {/* Export Button */}
              <button
                onClick={handleExport}
                disabled={isGenerating}
                className={`w-full py-3 px-4 rounded-lg font-medium text-white transition-colors ${
                  isGenerating
                    ? 'bg-gray-400 cursor-not-allowed'
                    : 'bg-blue-600 hover:bg-blue-700'
                }`}
              >
                {isGenerating ? (
                  <span className="flex items-center justify-center gap-2">
                    <svg
                      className="animate-spin h-5 w-5"
                      xmlns="http://www.w3.org/2000/svg"
                      fill="none"
                      viewBox="0 0 24 24"
                    >
                      <circle
                        className="opacity-25"
                        cx="12"
                        cy="12"
                        r="10"
                        stroke="currentColor"
                        strokeWidth="4"
                      />
                      <path
                        className="opacity-75"
                        fill="currentColor"
                        d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"
                      />
                    </svg>
                    Wird generiert...
                  </span>
                ) : (
                  `${reportMeta.title} exportieren`
                )}
              </button>
            </div>
          </div>

          {/* Recent Reports */}
          <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
            <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700">
              <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                Letzte Reports
              </h2>
            </div>
            <div className="p-4">
              {generatedReports.length === 0 ? (
                <p className="text-sm text-gray-500 dark:text-gray-400 text-center py-4">
                  Noch keine Reports generiert
                </p>
              ) : (
                <div className="space-y-3">
                  {generatedReports.slice(0, 5).map((report) => (
                    <div
                      key={report.id}
                      className="flex items-center justify-between p-3 bg-gray-50 dark:bg-gray-700/50 rounded-lg"
                    >
                      <div className="flex items-center gap-3">
                        <span className="text-lg">
                          {REPORT_TYPE_META[report.type].icon}
                        </span>
                        <div>
                          <p className="text-sm font-medium text-gray-900 dark:text-white">
                            {report.filename}
                          </p>
                          <p className="text-xs text-gray-500 dark:text-gray-400">
                            {report.generatedAt.toLocaleString('de-DE')}
                          </p>
                        </div>
                      </div>
                      <button className="text-blue-600 hover:text-blue-800 dark:text-blue-400">
                        <svg
                          className="h-5 w-5"
                          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-4-4l-4 4m0 0l-4-4m4 4V4"
                          />
                        </svg>
                      </button>
                    </div>
                  ))}
                </div>
              )}
            </div>
          </div>

          {/* Help / Templates */}
          <div className="bg-white dark:bg-gray-800 rounded-lg shadow">
            <div className="px-6 py-4 border-b border-gray-200 dark:border-gray-700">
              <h2 className="text-lg font-semibold text-gray-900 dark:text-white">
                Hilfe
              </h2>
            </div>
            <div className="p-4 space-y-3 text-sm">
              <div className="flex gap-2">
                <span>📋</span>
                <div>
                  <p className="font-medium text-gray-900 dark:text-white">
                    VVT Export
                  </p>
                  <p className="text-gray-500 dark:text-gray-400">
                    Art. 30 DSGVO konformes Verzeichnis aller
                    Verarbeitungstätigkeiten
                  </p>
                </div>
              </div>
              <div className="flex gap-2">
                <span>🔍</span>
                <div>
                  <p className="font-medium text-gray-900 dark:text-white">
                    Vendor Audit
                  </p>
                  <p className="text-gray-500 dark:text-gray-400">
                    Komplette Dokumentation für Due Diligence und Audits
                  </p>
                </div>
              </div>
              <div className="flex gap-2">
                <span>📊</span>
                <div>
                  <p className="font-medium text-gray-900 dark:text-white">
                    Management Summary
                  </p>
                  <p className="text-gray-500 dark:text-gray-400">
                    Übersicht für Geschäftsführung und DSB
                  </p>
                </div>
              </div>
            </div>
          </div>
        </div>
      </div>
    </div>
  )
}

// Helper Components

function StatCard({
  label,
  value,
  subtext,
  color,
}: {
  label: string
  value: number
  subtext: string
  color: 'blue' | 'purple' | 'green' | 'yellow' | 'red'
}) {
  const colors = {
    blue: 'bg-blue-50 dark:bg-blue-900/20',
    purple: 'bg-purple-50 dark:bg-purple-900/20',
    green: 'bg-green-50 dark:bg-green-900/20',
    yellow: 'bg-yellow-50 dark:bg-yellow-900/20',
    red: 'bg-red-50 dark:bg-red-900/20',
  }

  return (
    <div className={`${colors[color]} rounded-lg p-4`}>
      <p className="text-sm text-gray-500 dark:text-gray-400">{label}</p>
      <p className="mt-1 text-2xl font-bold text-gray-900 dark:text-white">
        {value}
      </p>
      <p className="text-xs text-gray-500 dark:text-gray-400">{subtext}</p>
    </div>
  )
}

function StatusBadge({ status }: { status: string }) {
  const statusStyles: Record<string, string> = {
    DRAFT: 'bg-gray-100 text-gray-700 dark:bg-gray-700 dark:text-gray-300',
    REVIEW: 'bg-yellow-100 text-yellow-700 dark:bg-yellow-900 dark:text-yellow-300',
    APPROVED: 'bg-green-100 text-green-700 dark:bg-green-900 dark:text-green-300',
    ARCHIVED: 'bg-gray-100 text-gray-500 dark:bg-gray-800 dark:text-gray-400',
  }

  return (
    <span
      className={`inline-flex items-center px-2 py-0.5 rounded text-xs font-medium ${
        statusStyles[status] || statusStyles.DRAFT
      }`}
    >
      {status}
    </span>
  )
}

function RiskBadge({ score }: { score: number }) {
  let colorClass = 'bg-green-100 text-green-700 dark:bg-green-900 dark:text-green-300'
  if (score >= 70) {
    colorClass = 'bg-red-100 text-red-700 dark:bg-red-900 dark:text-red-300'
  } else if (score >= 50) {
    colorClass = 'bg-yellow-100 text-yellow-700 dark:bg-yellow-900 dark:text-yellow-300'
  }

  return (
    <span
      className={`inline-flex items-center px-2 py-0.5 rounded text-xs font-medium ${colorClass}`}
    >
      {score}
    </span>
  )
}