'use client'

/**
 * OCR Import Panel
 *
 * Loads OCR export data from the klausur-service API (shared between admin-v2 and studio-v2)
 * and imports recognized words as editable text objects onto the Fabric.js canvas.
 */

import { useState, useEffect, useCallback } from 'react'
import { useTheme } from '@/lib/ThemeContext'
import { useWorksheet } from '@/lib/worksheet-editor/WorksheetContext'
import type { OCRExportData, OCRWord } from '@/lib/worksheet-editor/ocr-integration'
import { createTextProps, getColumnColor } from '@/lib/worksheet-editor/ocr-integration'

interface OCRImportPanelProps {
  isOpen: boolean
  onClose: () => void
}

export function OCRImportPanel({ isOpen, onClose }: OCRImportPanelProps) {
  const { isDark } = useTheme()
  const { canvas, saveToHistory } = useWorksheet()

  const [loading, setLoading] = useState(false)
  const [error, setError] = useState<string | null>(null)
  const [ocrData, setOcrData] = useState<OCRExportData | null>(null)
  const [selectedWords, setSelectedWords] = useState<Set<number>>(new Set())
  const [importing, setImporting] = useState(false)
  const [importSuccess, setImportSuccess] = useState(false)

  // Load OCR data when panel opens
  useEffect(() => {
    if (!isOpen) return
    loadOCRData()
  }, [isOpen])

  const loadOCRData = useCallback(async () => {
    setLoading(true)
    setError(null)
    setOcrData(null)
    setSelectedWords(new Set())
    setImportSuccess(false)

    try {
      const res = await fetch('/klausur-api/api/v1/vocab/ocr-export/latest')
      if (!res.ok) {
        throw new Error('not_found')
      }
      const data: OCRExportData = await res.json()
      setOcrData(data)
      // Select all words by default
      setSelectedWords(new Set(data.words.map((_, i) => i)))
    } catch {
      setError(
        'Keine OCR-Daten gefunden. Bitte zuerst im OCR-Compare Tool "Zum Editor exportieren" klicken.'
      )
    } finally {
      setLoading(false)
    }
  }, [])

  const toggleWord = useCallback((index: number) => {
    setSelectedWords(prev => {
      const next = new Set(prev)
      if (next.has(index)) {
        next.delete(index)
      } else {
        next.add(index)
      }
      return next
    })
  }, [])

  const selectAll = useCallback(() => {
    if (!ocrData) return
    setSelectedWords(new Set(ocrData.words.map((_, i) => i)))
  }, [ocrData])

  const deselectAll = useCallback(() => {
    setSelectedWords(new Set())
  }, [])

  const handleImport = useCallback(async () => {
    if (!ocrData || !canvas || selectedWords.size === 0) return

    setImporting(true)

    try {
      // Dynamic import of fabric to avoid SSR issues
      const { IText } = await import('fabric')

      // Save current state for undo
      if (saveToHistory) {
        saveToHistory('OCR Import')
      }

      const wordsToImport = ocrData.words.filter((_, i) => selectedWords.has(i))

      for (const word of wordsToImport) {
        const props = createTextProps(word)

        const textObj = new IText(props.text, {
          left: props.left,
          top: props.top,
          fontSize: props.fontSize,
          fontFamily: props.fontFamily,
          fill: props.fill,
          editable: true,
        })

        canvas.add(textObj)
      }

      canvas.renderAll()
      setImportSuccess(true)

      // Close after brief delay
      setTimeout(() => {
        onClose()
      }, 1500)
    } catch (e) {
      console.error('Import failed:', e)
      setError('Import fehlgeschlagen. Bitte erneut versuchen.')
    } finally {
      setImporting(false)
    }
  }, [ocrData, canvas, selectedWords, saveToHistory, onClose])

  if (!isOpen) return null

  // Count column types
  const columnSummary = ocrData
    ? ocrData.words.reduce<Record<string, number>>((acc, w) => {
        acc[w.column_type] = (acc[w.column_type] || 0) + 1
        return acc
      }, {})
    : {}

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center p-4">
      {/* Backdrop */}
      <div
        className="absolute inset-0 bg-black/50 backdrop-blur-sm"
        onClick={onClose}
      />

      {/* Panel */}
      <div
        className={`relative w-full max-w-2xl max-h-[85vh] rounded-3xl overflow-hidden flex flex-col ${
          isDark
            ? 'bg-slate-900/95 border border-white/10'
            : 'bg-white/95 border border-slate-200'
        } backdrop-blur-xl`}
      >
        {/* Header */}
        <div
          className={`flex items-center justify-between px-6 py-4 border-b ${
            isDark ? 'border-white/10' : 'border-slate-200'
          }`}
        >
          <div>
            <h2
              className={`text-xl font-bold ${
                isDark ? 'text-white' : 'text-slate-900'
              }`}
            >
              OCR Daten importieren
            </h2>
            <p
              className={`text-sm mt-0.5 ${
                isDark ? 'text-white/50' : 'text-slate-500'
              }`}
            >
              Erkannte Texte aus der Grid-Analyse einfuegen
            </p>
          </div>
          <button
            onClick={onClose}
            className={`p-2 rounded-lg transition-colors ${
              isDark ? 'hover:bg-white/10' : 'hover:bg-slate-100'
            }`}
          >
            <svg
              className={`w-5 h-5 ${isDark ? 'text-white' : 'text-slate-600'}`}
              fill="none"
              stroke="currentColor"
              viewBox="0 0 24 24"
            >
              <path
                strokeLinecap="round"
                strokeLinejoin="round"
                strokeWidth={2}
                d="M6 18L18 6M6 6l12 12"
              />
            </svg>
          </button>
        </div>

        {/* Content */}
        <div className="flex-1 overflow-y-auto px-6 py-4">
          {/* Loading */}
          {loading && (
            <div className="flex flex-col items-center justify-center py-12">
              <div className="animate-spin w-8 h-8 border-4 border-green-500 border-t-transparent rounded-full" />
              <p
                className={`mt-3 text-sm ${
                  isDark ? 'text-white/50' : 'text-slate-500'
                }`}
              >
                Lade OCR-Daten...
              </p>
            </div>
          )}

          {/* Error */}
          {error && (
            <div
              className={`p-4 rounded-xl text-center ${
                isDark
                  ? 'bg-red-500/10 text-red-300'
                  : 'bg-red-50 text-red-700'
              }`}
            >
              <svg
                className="w-8 h-8 mx-auto mb-2 opacity-50"
                fill="none"
                stroke="currentColor"
                viewBox="0 0 24 24"
              >
                <path
                  strokeLinecap="round"
                  strokeLinejoin="round"
                  strokeWidth={1.5}
                  d="M12 9v2m0 4h.01m-6.938 4h13.856c1.54 0 2.502-1.667 1.732-2.5L13.732 4c-.77-.833-1.964-.833-2.732 0L4.082 16.5c-.77.833.192 2.5 1.732 2.5z"
                />
              </svg>
              <p className="text-sm">{error}</p>
              <button
                onClick={loadOCRData}
                className={`mt-3 px-4 py-2 rounded-lg text-sm font-medium transition-colors ${
                  isDark
                    ? 'bg-white/10 text-white hover:bg-white/20'
                    : 'bg-slate-100 text-slate-700 hover:bg-slate-200'
                }`}
              >
                Erneut versuchen
              </button>
            </div>
          )}

          {/* Success State */}
          {importSuccess && (
            <div
              className={`p-6 rounded-xl text-center ${
                isDark
                  ? 'bg-green-500/10 text-green-300'
                  : 'bg-green-50 text-green-700'
              }`}
            >
              <svg
                className="w-12 h-12 mx-auto mb-3"
                fill="none"
                stroke="currentColor"
                viewBox="0 0 24 24"
              >
                <path
                  strokeLinecap="round"
                  strokeLinejoin="round"
                  strokeWidth={2}
                  d="M5 13l4 4L19 7"
                />
              </svg>
              <p className="font-medium">
                {selectedWords.size} Texte erfolgreich importiert!
              </p>
            </div>
          )}

          {/* OCR Data Display */}
          {ocrData && !importSuccess && (
            <>
              {/* Summary */}
              <div
                className={`p-4 rounded-xl mb-4 ${
                  isDark ? 'bg-white/5' : 'bg-slate-50'
                }`}
              >
                <div className="flex flex-wrap gap-3 mb-2">
                  <span
                    className={`px-3 py-1 rounded-lg text-sm font-medium ${
                      isDark
                        ? 'bg-green-500/20 text-green-300'
                        : 'bg-green-100 text-green-700'
                    }`}
                  >
                    {ocrData.words.length} Woerter
                  </span>
                  {Object.entries(columnSummary).map(([type, count]) => (
                    <span
                      key={type}
                      className="px-3 py-1 rounded-lg text-sm font-medium"
                      style={{
                        backgroundColor: getColumnColor(type as any) + '15',
                        color: getColumnColor(type as any),
                      }}
                    >
                      {type === 'english'
                        ? 'Englisch'
                        : type === 'german'
                          ? 'Deutsch'
                          : type === 'example'
                            ? 'Beispiel'
                            : 'Unbekannt'}
                      : {count}
                    </span>
                  ))}
                </div>
                <p
                  className={`text-xs ${
                    isDark ? 'text-white/40' : 'text-slate-400'
                  }`}
                >
                  Session: {ocrData.session_id.slice(0, 8)}... | Seite{' '}
                  {ocrData.page_number} | Exportiert:{' '}
                  {new Date(ocrData.exported_at).toLocaleString('de-DE')}
                </p>
              </div>

              {/* Selection Controls */}
              <div className="flex items-center justify-between mb-3">
                <span
                  className={`text-sm font-medium ${
                    isDark ? 'text-white/70' : 'text-slate-600'
                  }`}
                >
                  {selectedWords.size} von {ocrData.words.length} ausgewaehlt
                </span>
                <div className="flex gap-2">
                  <button
                    onClick={selectAll}
                    className={`px-3 py-1 rounded-lg text-xs font-medium transition-colors ${
                      isDark
                        ? 'bg-white/10 text-white/70 hover:bg-white/20'
                        : 'bg-slate-100 text-slate-600 hover:bg-slate-200'
                    }`}
                  >
                    Alle
                  </button>
                  <button
                    onClick={deselectAll}
                    className={`px-3 py-1 rounded-lg text-xs font-medium transition-colors ${
                      isDark
                        ? 'bg-white/10 text-white/70 hover:bg-white/20'
                        : 'bg-slate-100 text-slate-600 hover:bg-slate-200'
                    }`}
                  >
                    Keine
                  </button>
                </div>
              </div>

              {/* Word List */}
              <div className="space-y-1 max-h-[40vh] overflow-y-auto">
                {ocrData.words.map((word, idx) => (
                  <label
                    key={idx}
                    className={`flex items-center gap-3 p-2 rounded-lg cursor-pointer transition-colors ${
                      selectedWords.has(idx)
                        ? isDark
                          ? 'bg-green-500/10'
                          : 'bg-green-50'
                        : isDark
                          ? 'hover:bg-white/5'
                          : 'hover:bg-slate-50'
                    }`}
                  >
                    <input
                      type="checkbox"
                      checked={selectedWords.has(idx)}
                      onChange={() => toggleWord(idx)}
                      className="rounded border-slate-300"
                    />
                    <span
                      className="w-2 h-2 rounded-full flex-shrink-0"
                      style={{
                        backgroundColor: getColumnColor(word.column_type),
                      }}
                    />
                    <span
                      className={`text-sm flex-1 ${
                        isDark ? 'text-white' : 'text-slate-900'
                      }`}
                    >
                      {word.text}
                    </span>
                    <span
                      className={`text-xs px-2 py-0.5 rounded ${
                        isDark ? 'bg-white/10 text-white/40' : 'bg-slate-100 text-slate-400'
                      }`}
                    >
                      {word.column_type === 'english'
                        ? 'EN'
                        : word.column_type === 'german'
                          ? 'DE'
                          : word.column_type === 'example'
                            ? 'Ex'
                            : '?'}
                    </span>
                  </label>
                ))}
              </div>
            </>
          )}
        </div>

        {/* Footer */}
        {ocrData && !importSuccess && (
          <div
            className={`px-6 py-4 border-t ${
              isDark ? 'border-white/10' : 'border-slate-200'
            }`}
          >
            <div className="flex items-center justify-between">
              <button
                onClick={onClose}
                className={`px-4 py-2 rounded-xl text-sm font-medium transition-colors ${
                  isDark
                    ? 'text-white/60 hover:bg-white/10'
                    : 'text-slate-600 hover:bg-slate-100'
                }`}
              >
                Abbrechen
              </button>
              <button
                onClick={handleImport}
                disabled={importing || selectedWords.size === 0}
                className={`px-6 py-2.5 rounded-xl text-sm font-medium transition-colors flex items-center gap-2 ${
                  selectedWords.size > 0
                    ? 'bg-green-600 text-white hover:bg-green-700'
                    : isDark
                      ? 'bg-white/10 text-white/30 cursor-not-allowed'
                      : 'bg-slate-200 text-slate-400 cursor-not-allowed'
                }`}
              >
                {importing ? (
                  <div className="w-4 h-4 border-2 border-white border-t-transparent rounded-full animate-spin" />
                ) : (
                  <svg
                    className="w-4 h-4"
                    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>
                )}
                {selectedWords.size} Texte importieren
              </button>
            </div>
          </div>
        )}
      </div>
    </div>
  )
}