/**
 * Pagina Output Review.
 *
 * Carica i risultati di un job completato e mostra:
 * - Griglia di PostCard con badge PN e Schwartz
 * - SlideViewer inline espandibile con edit inline
 * - Pulsante Download CSV (POST /api/export/{jobId}/csv con edits)
 *
 * Lo stato dei post (con le modifiche inline) è mantenuto localmente
 * e inviato al backend via POST al momento del download CSV.
 */

import { Download, Loader2, RefreshCw } from 'lucide-react'
import { useEffect, useState } from 'react'
import { Link, useParams } from 'react-router-dom'
import { useDownloadEditedCsv, useJobResults, useSettingsStatus } from '../api/hooks'
import { PostCard } from '../components/PostCard'
import type { PostResult } from '../types'

export function OutputReview() {
  const { jobId } = useParams<{ jobId: string }>()
  const { data: jobData, isLoading, error } = useJobResults(jobId ?? null)
  const downloadMutation = useDownloadEditedCsv()
  const { data: settingsStatus } = useSettingsStatus()

  // Stato locale dei post — viene aggiornato da edit inline e rigenerazione
  const [localResults, setLocalResults] = useState<PostResult[]>([])
  // Set di indici dei post che sono stati rigenerati
  const [regeneratedSlots, setRegeneratedSlots] = useState<Set<number>>(new Set())

  // Inizializza i risultati e merge con CalendarSlot dal calendario
  useEffect(() => {
    if (jobData?.results) {
      const slots = jobData.calendar?.slots
      const merged = jobData.results.map((r) => ({
        ...r,
        slot: slots?.find((s) => s.indice === r.slot_index) ?? r.slot,
      }))
      setLocalResults(merged)
    }
  }, [jobData])

  function handleEdit(updated: PostResult) {
    setLocalResults((prev) =>
      prev.map((r) => (r.slot_index === updated.slot_index ? updated : r))
    )
  }

  function handleRegenerated(updated: PostResult) {
    setLocalResults((prev) =>
      prev.map((r) => (r.slot_index === updated.slot_index ? updated : r))
    )
    setRegeneratedSlots((prev) => new Set(prev).add(updated.slot_index))
  }

  async function handleDownloadCsv() {
    if (!jobId || !jobData) return
    await downloadMutation.mutateAsync({
      jobId,
      results: localResults,
      campagna: jobData.campagna,
    })
  }

  // ---------------------------------------------------------------------------
  // Loading / Error states
  // ---------------------------------------------------------------------------

  if (isLoading) {
    return (
      <div className="flex items-center justify-center min-h-64">
        <Loader2 className="animate-spin text-stone-500" size={24} />
      </div>
    )
  }

  if (error || !jobData) {
    return (
      <div className="max-w-2xl mx-auto px-6 py-10">
        <div className="px-4 py-3 rounded-lg bg-red-500/10 border border-red-500/30 text-sm text-red-400">
          {error?.message ?? 'Risultati non trovati. Il job potrebbe non essere completato.'}
        </div>
      </div>
    )
  }

  const successCount = localResults.filter((r) => r.status === 'success').length
  const failedCount = localResults.filter((r) => r.status === 'failed').length
  const regeneratedCount = regeneratedSlots.size
  // Conteggio post modificati manualmente (diversi dall'originale, esclusi i rigenerati)
  const editedCount = localResults.filter((r) => {
    if (r.status !== 'success' || !r.post) return false
    const original = jobData?.results?.find((o) => o.slot_index === r.slot_index)
    if (!original?.post) return false
    return JSON.stringify(r.post) !== JSON.stringify(original.post)
  }).length
  const manuallyEditedCount = Math.max(0, editedCount - regeneratedCount)

  // ---------------------------------------------------------------------------
  // UI principale
  // ---------------------------------------------------------------------------

  return (
    <div className="max-w-4xl mx-auto px-6 py-10 space-y-6">
      {/* Header */}
      <div className="flex items-start justify-between gap-4">
        <div>
          <h1 className="text-2xl font-bold text-stone-100">Output Review</h1>
          <p className="mt-1 text-stone-400 text-sm">{jobData.campagna}</p>
          <div className="flex flex-wrap items-center gap-x-4 gap-y-1 mt-2">
            <span className="text-xs text-stone-300 font-medium">{localResults.length} post</span>
            <span className="text-xs text-emerald-400">{successCount} generati</span>
            {failedCount > 0 && (
              <span className="text-xs text-red-400">{failedCount} falliti</span>
            )}
            {regeneratedCount > 0 && (
              <span className="text-xs text-amber-400 flex items-center gap-1">
                <RefreshCw size={10} />
                {regeneratedCount} rigenerati
              </span>
            )}
            {manuallyEditedCount > 0 && (
              <span className="text-xs text-blue-400">
                {manuallyEditedCount} modificati
              </span>
            )}
            <span className="text-xs text-stone-600">job: {jobId}</span>
          </div>
        </div>

        {/* Download CSV */}
        <button
          onClick={handleDownloadCsv}
          disabled={downloadMutation.isPending || successCount === 0}
          className="flex-shrink-0 flex items-center gap-2 px-4 py-2.5 rounded-lg bg-amber-500 text-stone-950 text-sm font-semibold hover:bg-amber-400 disabled:opacity-50 disabled:cursor-not-allowed transition-colors"
        >
          {downloadMutation.isPending ? (
            <Loader2 size={14} className="animate-spin" />
          ) : (
            <Download size={14} />
          )}
          {downloadMutation.isPending ? 'Download...' : 'Download CSV'}
        </button>
      </div>

      {/* Errore download */}
      {downloadMutation.error && (
        <div className="px-4 py-3 rounded-lg bg-red-500/10 border border-red-500/30 text-sm text-red-400">
          Errore download: {downloadMutation.error.message}
        </div>
      )}

      {/* Info edit inline */}
      <div className="px-4 py-2.5 rounded-lg bg-stone-800/50 border border-stone-700 text-xs text-stone-500">
        Clicca su una card per espandere le slide. I campi di testo sono editabili inline.
        Usa il pulsante <RefreshCw size={10} className="inline" /> per rigenerare singoli post con topic diversi.
        Le modifiche saranno incluse nel CSV scaricato.
      </div>

      {/* Hint Unsplash — visibile solo se non configurato */}
      {settingsStatus && !settingsStatus.unsplash_api_key_configured && (
        <div className="px-4 py-2 rounded-lg bg-stone-800/30 border border-stone-700/50 text-xs text-stone-600 flex items-center gap-2 flex-wrap">
          <span>Le colonne immagine contengono keyword testuali.</span>
          <Link
            to="/impostazioni"
            className="text-amber-500/70 hover:text-amber-400 underline underline-offset-2 transition-colors"
          >
            Configura Unsplash
          </Link>
          <span>per URL immagini reali nel CSV.</span>
        </div>
      )}

      {/* Griglia post */}
      <div className="space-y-3">
        {localResults.length === 0 ? (
          <p className="text-sm text-stone-500 text-center py-8">
            Nessun risultato disponibile.
          </p>
        ) : (
          localResults.map((result) => (
            <PostCard
              key={result.slot_index}
              result={result}
              obiettivoCampagna={jobData.campagna}
              brandName={null}
              tono={null}
              onRegenerated={handleRegenerated}
              onEdit={handleEdit}
              isRegenerated={regeneratedSlots.has(result.slot_index)}
            />
          ))
        )}
      </div>

      {/* Download CSV footer */}
      {successCount > 0 && (
        <div className="flex justify-center pt-4">
          <button
            onClick={handleDownloadCsv}
            disabled={downloadMutation.isPending}
            className="flex items-center gap-2 px-6 py-3 rounded-lg bg-amber-500 text-stone-950 text-sm font-semibold hover:bg-amber-400 disabled:opacity-50 transition-colors"
          >
            {downloadMutation.isPending ? (
              <Loader2 size={15} className="animate-spin" />
            ) : (
              <Download size={15} />
            )}
            {downloadMutation.isPending ? 'Download CSV...' : `Scarica CSV (${successCount} post)`}
          </button>
        </div>
      )}
    </div>
  )
}