'use client'

import React, { useEffect, useState, useCallback, use } from 'react'
import { useRouter } from 'next/navigation'
import { ClassificationBadge } from '../../_components/ClassificationBadge'

interface CRAProject {
  id: string
  name: string
  intended_use: string
  primary_language: string | null
  connected_to_internet: boolean
  has_software_updates: boolean
  processes_personal_data: boolean
  is_critical_infra_supplier: boolean
  cra_classification: string | null
  classification_rationale: string[]
  status: string
}

const CLASSIFICATION_DESC: Record<string, string> = {
  NOT_IN_SCOPE: 'Dein Produkt enthaelt keine digitalen Elemente nach CRA-Definition. Es ist nicht vom CRA betroffen.',
  STANDARD: 'Default-Kategorie fuer Produkte mit digitalen Elementen. Self-Assessment (Modul A) ist der typische Pfad.',
  IMPORTANT_I: 'Annex III Klasse I — Wichtige Produkte mit erhoehten Anforderungen. Self-Assessment OR Harmonized Standard moeglich.',
  IMPORTANT_II: 'Annex III Klasse II — Wichtige Produkte mit hohem Sicherheitsbedarf. Harmonized Standard ODER EUCC ODER Notified Body.',
  CRITICAL: 'Annex IV — Kritische Produkte (z.B. HSM, Smart-Meter-Gateways). Notified-Body-Assessment Pflicht.',
}

export default function ScopeCheckPage({
  params,
}: {
  params: Promise<{ projectId: string }>
}) {
  const { projectId } = use(params)
  const router = useRouter()
  const [project, setProject] = useState<CRAProject | null>(null)
  const [loading, setLoading] = useState(true)
  const [checking, setChecking] = useState(false)
  const [error, setError] = useState('')

  const tenant = '00000000-0000-0000-0000-000000000001'

  const load = useCallback(async () => {
    try {
      const res = await fetch(`/api/sdk/v1/cra/projects/${projectId}`, {
        headers: { 'X-Tenant-ID': tenant },
      })
      if (!res.ok) throw new Error(await res.text())
      setProject(await res.json())
    } catch (e) {
      setError(e instanceof Error ? e.message : 'Fehler beim Laden')
    } finally {
      setLoading(false)
    }
  }, [projectId])

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

  const runScopeCheck = async () => {
    setChecking(true)
    setError('')
    try {
      const res = await fetch(`/api/sdk/v1/cra/projects/${projectId}/scope-check`, {
        method: 'POST',
        headers: { 'X-Tenant-ID': tenant },
      })
      if (!res.ok) throw new Error(await res.text())
      setProject(await res.json())
    } catch (e) {
      setError(e instanceof Error ? e.message : 'Klassifikation fehlgeschlagen')
    } finally {
      setChecking(false)
    }
  }

  if (loading) return <div className="min-h-screen bg-gray-50 p-8"><p className="text-gray-500">Laedt...</p></div>
  if (!project) return null

  const hasResult = !!project.cra_classification

  return (
    <div className="min-h-screen bg-gray-50 py-8">
      <div className="max-w-3xl mx-auto px-4">
        <div className="mb-6">
          <a href={`/sdk/cra/${projectId}`} className="text-sm text-blue-600 hover:underline">
            &larr; Zurueck zum Projekt
          </a>
          <h1 className="text-2xl font-bold text-gray-900 mt-2">Scope-Check & Klassifikation</h1>
          <p className="text-sm text-gray-600 mt-1">
            Schritt 2 von 3 — Wir matchen dein Intake gegen Annex III/IV des CRA.
          </p>
        </div>

        {error && (
          <div className="mb-4 bg-red-50 border border-red-200 rounded-lg p-3 text-sm text-red-700">{error}</div>
        )}

        <div className="bg-white rounded-xl shadow-sm border border-gray-200 p-6 space-y-4">
          <h3 className="text-sm font-semibold text-gray-700">Aktuelle Intake-Daten</h3>
          <dl className="grid grid-cols-1 md:grid-cols-2 gap-2 text-sm">
            <Field label="Produkt" value={project.name} />
            <Field label="Sprache" value={project.primary_language || '—'} />
            <Field label="Intended Use" value={project.intended_use || '—'} fullWidth />
            <Field label="Internet" value={project.connected_to_internet ? 'Ja' : 'Nein'} />
            <Field label="Software-Updates" value={project.has_software_updates ? 'Ja' : 'Nein'} />
            <Field label="Personenbezogene Daten" value={project.processes_personal_data ? 'Ja' : 'Nein'} />
            <Field label="Kritische Infra" value={project.is_critical_infra_supplier ? 'Ja' : 'Nein'} />
          </dl>

          <div className="border-t border-gray-200 pt-4">
            <button
              onClick={runScopeCheck}
              disabled={checking}
              className="w-full py-3 bg-red-600 text-white font-medium rounded-lg hover:bg-red-700 disabled:bg-gray-300"
            >
              {checking ? 'Pruefe...' : hasResult ? 'Klassifikation neu berechnen' : 'Klassifikation berechnen'}
            </button>
          </div>
        </div>

        {hasResult && (
          <div className="mt-6 bg-white rounded-xl shadow-sm border border-gray-200 p-6">
            <h3 className="text-sm font-semibold text-gray-700 uppercase tracking-wide mb-3">Ergebnis</h3>
            <div className="flex items-center gap-4 mb-4">
              <ClassificationBadge value={project.cra_classification} size="lg" />
              <p className="text-sm text-gray-700">
                {CLASSIFICATION_DESC[project.cra_classification!]}
              </p>
            </div>
            {project.classification_rationale?.length > 0 && (
              <div className="bg-gray-50 rounded-lg p-4 mb-4">
                <p className="text-xs font-semibold text-gray-600 uppercase tracking-wide mb-2">Begruendung</p>
                <ul className="list-disc list-inside space-y-1 text-sm text-gray-700">
                  {project.classification_rationale.map((r, i) => <li key={i}>{r}</li>)}
                </ul>
              </div>
            )}
            <div className="flex gap-3">
              <button
                onClick={() => router.push(`/sdk/cra/${projectId}/intake`)}
                className="px-4 py-2 border border-gray-300 text-gray-700 rounded-lg hover:bg-gray-50"
              >
                ← Intake anpassen
              </button>
              <button
                onClick={() => router.push(`/sdk/cra/${projectId}/path`)}
                disabled={project.cra_classification === 'NOT_IN_SCOPE'}
                className="flex-1 py-2 bg-red-600 text-white font-medium rounded-lg hover:bg-red-700 disabled:bg-gray-300"
              >
                Weiter zum Konformitaetspfad →
              </button>
            </div>
            {project.cra_classification === 'NOT_IN_SCOPE' && (
              <p className="text-xs text-gray-500 mt-2 text-center">
                Produkt ist nicht im CRA-Scope. Keine weiteren Schritte noetig.
              </p>
            )}
          </div>
        )}
      </div>
    </div>
  )
}

function Field({ label, value, fullWidth }: { label: string; value: string; fullWidth?: boolean }) {
  return (
    <div className={fullWidth ? 'md:col-span-2' : ''}>
      <dt className="text-xs text-gray-500">{label}</dt>
      <dd className="text-gray-900 mt-0.5">{value}</dd>
    </div>
  )
}