import { useState, useEffect } from 'react'
import { Brain, Trash2, ChevronDown, ChevronUp } from 'lucide-react'
import { api } from '../utils/api'
import { useAuth } from '../context/AuthContext'
import Markdown from '../utils/Markdown'
import UsageBadge from '../components/UsageBadge'
import dayjs from 'dayjs'
import 'dayjs/locale/de'
dayjs.locale('de')

// Legacy fallback labels (display_name takes precedence)
const SLUG_LABELS = {
  pipeline: '🔬 Mehrstufige Gesamtanalyse'
}

function InsightCard({ ins, onDelete, defaultOpen=false, prompts=[] }) {
  const [open, setOpen] = useState(defaultOpen)

  // Find matching prompt to get display_name
  const prompt = prompts.find(p => p.slug === ins.scope)
  const displayName = prompt?.display_name || SLUG_LABELS[ins.scope] || ins.scope

  return (
    <div className="card section-gap" style={{borderLeft:`3px solid var(--accent)`}}>
      <div style={{display:'flex',alignItems:'center',gap:8,marginBottom:open?12:0,cursor:'pointer'}}
        onClick={()=>setOpen(o=>!o)}>
        <div style={{flex:1}}>
          <div style={{fontSize:13,fontWeight:600}}>
            {displayName}
          </div>
          <div style={{fontSize:11,color:'var(--text3)'}}>
            {dayjs(ins.created).format('DD. MMMM YYYY, HH:mm')}
          </div>
        </div>
        <button style={{background:'none',border:'none',cursor:'pointer',color:'var(--text3)',padding:4}}
          onClick={e=>{e.stopPropagation();onDelete(ins.id)}}>
          <Trash2 size={13}/>
        </button>
        {open ? <ChevronUp size={16} color="var(--text3)"/> : <ChevronDown size={16} color="var(--text3)"/>}
      </div>
      {open && <Markdown text={ins.content}/>}
    </div>
  )
}


export default function Analysis() {
  const { canUseAI } = useAuth()
  const [prompts,     setPrompts]     = useState([])
  const [allInsights, setAllInsights] = useState([])
  const [loading,     setLoading]     = useState(null)
  const [error,       setError]       = useState(null)
  const [tab,         setTab]         = useState('run')
  const [newResult,   setNewResult]   = useState(null)
  const [aiUsage, setAiUsage] = useState(null)

  const loadAll = async () => {
    const [p, i] = await Promise.all([
      api.listPrompts(),
      api.listInsights()
    ])
    setPrompts(Array.isArray(p)?p:[])
    setAllInsights(Array.isArray(i)?i:[])
  }

  useEffect(()=>{
    loadAll()
    // Load feature usage for badges
    api.getFeatureUsage().then(features => {
      const aiFeature = features.find(f => f.feature_id === 'ai_calls')
      setAiUsage(aiFeature)
    }).catch(err => console.error('Failed to load usage:', err))
  },[])

  const runPrompt = async (slug) => {
    setLoading(slug); setError(null); setNewResult(null)
    try {
      // Use new unified executor with save=true
      const result = await api.executeUnifiedPrompt(slug, null, null, false, true)

      // Transform result to match old format for InsightCard
      let content = ''
      if (result.type === 'pipeline') {
        // For pipeline, extract final output
        const finalOutput = result.output || {}
        if (typeof finalOutput === 'object' && Object.keys(finalOutput).length === 1) {
          content = Object.values(finalOutput)[0]
        } else {
          content = JSON.stringify(finalOutput, null, 2)
        }
      } else {
        // For base prompts, use output directly
        content = typeof result.output === 'string' ? result.output : JSON.stringify(result.output, null, 2)
      }

      setNewResult({ scope: slug, content })
      await loadAll()
      setTab('run')
    } catch(e) {
      setError('Fehler: ' + e.message)
    } finally { setLoading(null) }
  }

  const deleteInsight = async (id) => {
    if (!confirm('Analyse löschen?')) return
    const pid = localStorage.getItem('bodytrack_active_profile')||''
    await fetch(`/api/insights/${id}`, {
      method:'DELETE', headers: pid ? {'X-Profile-Id':pid} : {}
    })
    if (newResult?.id === id) setNewResult(null)
    await loadAll()
  }

  // Group insights by scope for history view
  const grouped = {}
  allInsights.forEach(ins => {
    const key = ins.scope || 'sonstige'
    grouped[key] = grouped[key] || []
    grouped[key].push(ins)
  })

  // Show only active pipeline-type prompts
  const pipelinePrompts = prompts.filter(p => p.active && p.type === 'pipeline')

  return (
    <div>
      <h1 className="page-title">KI-Analyse</h1>

      <div className="tabs">
        <button className={'tab'+(tab==='run'?' active':'')} onClick={()=>setTab('run')}>Analysen starten</button>
        <button className={'tab'+(tab==='history'?' active':'')} onClick={()=>setTab('history')}>
          Verlauf
          {allInsights.length>0 && <span style={{marginLeft:4,fontSize:10,background:'var(--accent)',
            color:'white',padding:'1px 5px',borderRadius:8}}>{allInsights.length}</span>}
        </button>
      </div>

      {error && (
        <div style={{padding:'10px 14px',background:'#FCEBEB',borderRadius:8,fontSize:13,
          color:'#D85A30',marginBottom:12,lineHeight:1.5}}>
          {error.includes('nicht aktiviert') || error.includes('Limit')
            ? <>🔒 <strong>KI-Zugang eingeschränkt</strong><br/>
                Dein Profil hat keinen Zugang zu KI-Analysen oder das Tageslimit wurde erreicht.
                Bitte den Admin kontaktieren.</>
            : error}
        </div>
      )}

      {/* ── Analysen starten ── */}
      {tab==='run' && (
        <div>
          {/* Fresh result shown immediately */}
          {newResult && (
            <div style={{marginBottom:16}}>
              <div style={{fontSize:12,fontWeight:600,color:'var(--accent)',marginBottom:8}}>
                ✅ Neue Analyse erstellt:
              </div>
              <InsightCard
                ins={{...newResult, created: new Date().toISOString()}}
                onDelete={deleteInsight}
                defaultOpen={true}
                prompts={prompts}
              />
            </div>
          )}

          {!canUseAI && (
            <div style={{padding:'14px 16px',background:'#FCEBEB',borderRadius:10,
              border:'1px solid #D85A3033',marginBottom:16}}>
              <div style={{fontSize:14,fontWeight:600,color:'#D85A30',marginBottom:4}}>
                🔒 KI-Analysen nicht freigeschaltet
              </div>
              <div style={{fontSize:13,color:'var(--text2)',lineHeight:1.5}}>
                Dein Profil hat keinen Zugang zu KI-Analysen.
                Bitte den Admin bitten, KI für dein Profil zu aktivieren
                (Einstellungen → Admin → Profil bearbeiten).
              </div>
            </div>
          )}

          {canUseAI && pipelinePrompts.length > 0 && (
            <p style={{fontSize:13,color:'var(--text2)',marginBottom:14,lineHeight:1.6}}>
              Wähle eine mehrstufige KI-Analyse:
            </p>
          )}

          {pipelinePrompts.map(p => {
            const existing = allInsights.find(i=>i.scope===p.slug)
            return (
              <div key={p.id} className="card" style={{marginBottom:16,borderColor:'var(--accent)',borderWidth:2}}>
                <div style={{display:'flex',alignItems:'flex-start',gap:12}}>
                  <div style={{flex:1}}>
                    <div className="badge-container-right" style={{fontWeight:700,fontSize:15,color:'var(--accent)'}}>
                      <span>{p.display_name || SLUG_LABELS[p.slug] || p.name}</span>
                      {aiUsage && <UsageBadge {...aiUsage} />}
                    </div>
                    {p.description && (
                      <div style={{fontSize:12,color:'var(--text2)',marginTop:3,lineHeight:1.5}}>
                        {p.description}
                      </div>
                    )}
                    {existing && (
                      <div style={{fontSize:11,color:'var(--text3)',marginTop:3}}>
                        Letzte Analyse: {dayjs(existing.created).format('DD.MM.YYYY, HH:mm')}
                      </div>
                    )}
                  </div>
                  <div
                    title={aiUsage && !aiUsage.allowed ? `Limit erreicht (${aiUsage.used}/${aiUsage.limit}). Kontaktiere den Admin oder warte bis zum nächsten Reset.` : ''}
                    style={{display:'inline-block'}}
                  >
                    <button
                      className="btn btn-primary"
                      style={{flexShrink:0,minWidth:100, cursor: (aiUsage && !aiUsage.allowed) ? 'not-allowed' : 'pointer'}}
                      onClick={()=>runPrompt(p.slug)}
                      disabled={!!loading||!canUseAI||(aiUsage && !aiUsage.allowed)}
                    >
                      {loading===p.slug
                        ? <><div className="spinner" style={{width:13,height:13}}/> Läuft…</>
                        : (aiUsage && !aiUsage.allowed) ? '🔒 Limit'
                        : <><Brain size={13}/> Starten</>}
                    </button>
                  </div>
                </div>
                {/* Show existing result collapsed */}
                {existing && newResult?.id !== existing.id && (
                  <div style={{marginTop:8,borderTop:'1px solid var(--border)',paddingTop:8}}>
                    <InsightCard ins={existing} onDelete={deleteInsight} defaultOpen={false} prompts={prompts}/>
                  </div>
                )}
              </div>
            )
          })}

          {canUseAI && pipelinePrompts.length === 0 && (
            <div className="empty-state">
              <p>Keine aktiven Pipeline-Prompts verfügbar.</p>
              <p style={{fontSize:12,color:'var(--text3)',marginTop:8}}>
                Erstelle Pipeline-Prompts im Admin-Bereich (Einstellungen → Admin → KI-Prompts).
              </p>
            </div>
          )}
        </div>
      )}

      {/* ── Verlauf gruppiert ── */}
      {tab==='history' && (
        <div>
          {allInsights.length===0
            ? <div className="empty-state"><h3>Noch keine Analysen</h3></div>
            : Object.entries(grouped).map(([scope, ins]) => (
              <div key={scope} style={{marginBottom:20}}>
                <div style={{fontSize:13,fontWeight:700,color:'var(--text3)',
                  textTransform:'uppercase',letterSpacing:'0.05em',marginBottom:8}}>
                  {prompts.find(p => p.slug === scope)?.display_name || SLUG_LABELS[scope] || scope} ({ins.length})
                </div>
                {ins.map(i => <InsightCard key={i.id} ins={i} onDelete={deleteInsight} prompts={prompts}/>)}
              </div>
            ))
          }
        </div>
      )}
    </div>
  )
}