'use client'

import React, { useState } from 'react'
import { ScanResult } from './_components/ScanResult'
import { ConsentTestResult } from './_components/ConsentTestResult'
import { CompareResult } from './_components/CompareResult'
import { AuthTestResult } from './_components/AuthTestResult'

type Mode = 'pre_launch' | 'post_launch'
type Tab = 'quick' | 'scan' | 'consent' | 'compare' | 'auth'

const MODES = [
  { id: 'pre_launch' as Mode, label: 'Internes Dokument', desc: 'Vor Veroeffentlichung', icon: '📋' },
  { id: 'post_launch' as Mode, label: 'Live-Website', desc: 'Bereits online', icon: '🌐' },
]

const TABS = [
  { id: 'quick' as Tab, label: 'Schnellanalyse', info: 'Einzelne URL klassifizieren und bewerten.' },
  { id: 'scan' as Tab, label: 'Website-Scan', info: '5-10 Seiten scannen, Dienstleister abgleichen, Pflichtinhalte pruefen.' },
  { id: 'consent' as Tab, label: 'Cookie-Test', info: 'Testet mit Browser was VOR und NACH Cookie-Einwilligung geladen wird.' },
  { id: 'compare' as Tab, label: 'Vergleich', info: '2-5 Websites parallel scannen und Compliance vergleichen.' },
  { id: 'auth' as Tab, label: 'Login-Test', info: 'Nach Login pruefen: Kuendigung, Daten loeschen, Export, Einwilligungen.' },
]

export default function AgentPage() {
  const [url, setUrl] = useState('')
  const [urls, setUrls] = useState('')
  const [mode, setMode] = useState<Mode>('post_launch')
  const [tab, setTab] = useState<Tab>('quick')
  const [scanLoading, setScanLoading] = useState(false)
  const [scanError, setScanError] = useState<string | null>(null)
  const [scanData, setScanData] = useState<any>(null)
  const [scanHistory, setScanHistory] = useState<any[]>([])
  const [consentData, setConsentData] = useState<any>(null)
  const [compareData, setCompareData] = useState<any>(null)
  const [authData, setAuthData] = useState<any>(null)
  const [authUser, setAuthUser] = useState('')
  const [authPass, setAuthPass] = useState('')
  const { analyze, answerFollowUp, loading, error, result, history } = useAgentAnalysis()

  React.useEffect(() => { localStorage.setItem('agent-scan-url', url) }, [url])
  React.useEffect(() => { localStorage.setItem('agent-scan-tab', tab) }, [tab])

  // Resume polling if scan was in progress
  React.useEffect(() => {
    if (!activeScanId || scanData?.services) return
    let cancelled = false
    setScanLoading(true)
    setScanProgress('Scan laeuft noch...')
    const poll = async () => {
      while (!cancelled) {
        await new Promise(r => setTimeout(r, 5000))
        try {
          const res = await fetch(`/api/sdk/v1/agent/scan?scan_id=${activeScanId}`)
          if (!res.ok) continue
          const data = await res.json()
          if (data.progress) setScanProgress(data.progress)
          if (data.status === 'completed' && data.result) {
            setScanData(data.result)
            setScanProgress('')
            setScanLoading(false)
            localStorage.setItem('agent-scan-result', JSON.stringify(data.result))
            localStorage.removeItem('agent-scan-id')
            setActiveScanId('')
            _addToHistory(data.result)
            return
          }
          if (data.status === 'failed' || data.status === 'not_found') {
            if (data.status === 'failed') setScanError(data.error || 'Scan fehlgeschlagen')
            setScanProgress('')
            setScanLoading(false)
            localStorage.removeItem('agent-scan-id')
            setActiveScanId('')
            return
          }
        } catch { /* retry */ }
      }
    }
    poll()
    return () => { cancelled = true }
  }, []) // eslint-disable-line react-hooks/exhaustive-deps

  const _addToHistory = (result: any) => {
    const resultKey = `scan-result-${Date.now()}`
    try { localStorage.setItem(resultKey, JSON.stringify(result)) } catch {}
    const entry = {
      url: url || result.url || '',
      date: new Date().toISOString(),
      findings: result.findings?.length || 0,
      docs: result.discovered_documents?.length || 0,
      resultKey,
    }
    const updated = [entry, ...scanHistory].slice(0, 30)
    setScanHistory(updated)
    localStorage.setItem('agent-scan-history', JSON.stringify(updated))
  }

  const handleScan = async (e: React.FormEvent) => {
    e.preventDefault()
    setScanLoading(true)
    setScanError(null)

    try {
      if (tab === 'quick') {
        setScanLoading(false)
        analyze(url.trim(), mode)
        return
      }

      let endpoint = ''
      let body: any = {}

      if (tab === 'scan') {
        endpoint = '/api/sdk/v1/agent/scan'
        body = { url: url.trim(), mode }
      } else if (tab === 'consent') {
        endpoint = '/api/sdk/v1/agent/consent-test'
        body = { url: url.trim() }
      } else if (tab === 'compare') {
        endpoint = '/api/sdk/v1/agent/compare'
        body = { urls: urls.split('\n').map(u => u.trim()).filter(Boolean), mode }
      } else if (tab === 'auth') {
        endpoint = '/api/sdk/v1/agent/authenticated-scan'
        body = { url: url.trim(), username: authUser, password: authPass }
      }

      const res = await fetch(endpoint, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body),
      })
      if (!res.ok) throw new Error(`Fehlgeschlagen: ${res.status}`)
      const data = await res.json()

      if (tab === 'scan') {
        setScanData(data)
        setScanHistory(prev => [{ url: url.trim(), ...data, scanned_at: new Date().toISOString() }, ...prev].slice(0, 20))
      } else if (tab === 'consent') setConsentData(data)
      else if (tab === 'compare') setCompareData(data)
      else if (tab === 'auth') setAuthData(data)
    } catch (e) {
      setScanError(e instanceof Error ? e.message : 'Fehler')
    } finally {
      setScanLoading(false)
    }
  }

  // Navigate to a specialized tab with a pre-filled URL
  const navigateToCheck = (targetTab: AnalysisTab, checkUrl: string) => {
    // Store the URL in the target tab's localStorage key
    const keyMap: Record<string, string> = {
      'doc-check': 'doc-check-prefill-url',
      'banner-check': 'banner-check-url',
      'impressum-check': 'impressum-check-url',
    }
    if (keyMap[targetTab]) {
      localStorage.setItem(keyMap[targetTab], checkUrl)
    }
    setTab(targetTab)
  }

  // Extract discovered documents for quick-action buttons
  const discoveredDocs = scanData?.discovered_documents || []
  const scannedUrl = scanData?.url || url

  return (
    <div className="space-y-6 max-w-4xl">
      <div>
        <h1 className="text-2xl font-bold text-gray-900">Compliance Agent</h1>
        <p className="text-gray-500 mt-1">Analysiere Dokumente und Webseiten auf DSGVO-Konformitaet.</p>
      </div>

      {/* Mode */}
      <div className="grid grid-cols-2 gap-3">
        {MODES.map(m => (
          <button key={m.id} onClick={() => setMode(m.id)}
            className={`p-3 rounded-xl border-2 text-left transition-all ${mode === m.id ? 'border-purple-500 bg-purple-50' : 'border-gray-200 hover:border-gray-300'}`}>
            <div className="flex items-center gap-3">
              <span className="text-xl">{m.icon}</span>
              <div>
                <p className={`text-sm font-semibold ${mode === m.id ? 'text-purple-900' : 'text-gray-900'}`}>{m.label}</p>
                <p className="text-xs text-gray-500">{m.desc}</p>
              </div>
            </div>
          </button>
        ))}
      </div>

      {/* Tabs */}
      <div>
        <div className="flex border-b border-gray-200 overflow-x-auto">
          {TABS.map(t => (
            <button key={t.id} onClick={() => setTab(t.id)}
              className={`px-3 py-2.5 text-sm font-medium border-b-2 whitespace-nowrap transition-colors ${tab === t.id ? 'border-purple-500 text-purple-700' : 'border-transparent text-gray-500 hover:text-gray-700'}`}>
              {t.label}
            </button>
          ))}
        </div>
        <p className="text-xs text-gray-400 mt-2 px-1">{TABS.find(t => t.id === tab)?.info}</p>
      </div>

      {/* Input */}
      <form onSubmit={handleSubmit} className="space-y-3">
        {tab === 'compare' ? (
          <textarea value={urls} onChange={e => setUrls(e.target.value)}
            placeholder="https://www.opodo.de&#10;https://www.booking.com&#10;https://www.expedia.de"
            rows={3}
            className="w-full px-4 py-3 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 text-sm"
            disabled={isLoading} />
        ) : (
          <input type="url" value={url} onChange={e => setUrl(e.target.value)}
            placeholder={tab === 'auth' ? 'https://www.example.com/login' : 'https://www.example.com/'}
            className="w-full px-4 py-3 border border-gray-300 rounded-lg focus:ring-2 focus:ring-purple-500 text-sm"
            disabled={isLoading} required />
        )}
        {tab === 'auth' && (
          <div className="grid grid-cols-2 gap-3">
            <input type="text" value={authUser} onChange={e => setAuthUser(e.target.value)}
              placeholder="Email / Benutzername" autoComplete="off"
              className="px-4 py-2 border border-gray-300 rounded-lg text-sm" />
            <input type="password" value={authPass} onChange={e => setAuthPass(e.target.value)}
              placeholder="Passwort" autoComplete="off"
              className="px-4 py-2 border border-gray-300 rounded-lg text-sm" />
            <p className="col-span-2 text-[10px] text-gray-400">Credentials werden NICHT gespeichert — nur fuer diesen Test im Browser-Kontext.</p>
          </div>
        )}
        <button type="submit" disabled={isLoading || (!url.trim() && tab !== 'compare') || (tab === 'compare' && !urls.trim())}
          className="px-6 py-3 bg-purple-600 text-white rounded-lg hover:bg-purple-700 disabled:opacity-50 transition-colors flex items-center gap-2 text-sm font-medium">
          {isLoading ? (
            <><svg className="animate-spin w-4 h-4" 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 12h4z" />
            </svg>Analysiere...</>
          ) : TABS.find(t => t.id === tab)?.label || 'Starten'}
        </button>
      </form>

      {currentError && <div className="bg-red-50 border border-red-200 rounded-lg p-4 text-sm text-red-700">{currentError}</div>}

      {/* Results */}
      {tab === 'quick' && result && (
        <div className="bg-white border border-gray-200 rounded-xl p-6 shadow-sm space-y-6">
          <AnalysisResult result={result} />
          {result.follow_up_questions.length > 0 && (
            <div className="border-t pt-4"><FollowUpQuestions questions={result.follow_up_questions} answers={result.follow_up_answers} onAnswer={answerFollowUp} /></div>
          )}
        </div>
      )}
      {tab === 'scan' && scanData && <div className="bg-white border border-gray-200 rounded-xl p-6 shadow-sm"><ScanResult data={scanData} /></div>}
      {tab === 'consent' && consentData && <div className="bg-white border border-gray-200 rounded-xl p-6 shadow-sm"><ConsentTestResult data={consentData} /></div>}
      {tab === 'compare' && compareData?.sites && <div className="bg-white border border-gray-200 rounded-xl p-6 shadow-sm"><CompareResult sites={compareData.sites} /></div>}
      {tab === 'auth' && authData && <div className="bg-white border border-gray-200 rounded-xl p-6 shadow-sm"><AuthTestResult data={authData} /></div>}

      {/* History */}
      {tab === 'quick' && <AnalysisHistory history={history} onSelect={r => { setUrl(r.url); analyze(r.url, mode) }} />}
      {tab === 'scan' && scanHistory.length > 0 && (
        <div>
          <h3 className="text-sm font-medium text-gray-700 mb-3">Letzte Scans</h3>
          <div className="space-y-2">
            {scanHistory.map((item, i) => (
              <button key={i} onClick={() => setUrl(item.url)}
                className="w-full text-left p-3 bg-white border border-gray-200 rounded-lg hover:border-purple-300 transition-colors">
                <div className="flex items-center gap-3">
                  <span className="text-xs text-gray-500 w-8">{item.pages_scanned}p</span>
                  <span className="text-sm text-gray-700 truncate flex-1">{item.url}</span>
                  <span className={`text-xs px-2 py-0.5 rounded ${item.findings?.length > 0 ? 'bg-red-100 text-red-700' : 'bg-green-100 text-green-700'}`}>{item.findings?.length || 0}</span>
                </div>
              </button>
            ))}
          </div>
        </div>
      )}
    </div>
  )
}