/**
 * RAGSearchPanel Component
 *
 * Enhanced RAG search panel for teachers to query their Erwartungshorizonte.
 * Features:
 * - search_info display (which RAG features were active)
 * - Confidence indicator based on re-ranking scores
 * - Toggle for "Enhanced Search" with advanced options
 */

import { useState, useCallback } from 'react'
import { ehApi, EHRAGResult } from '../services/api'

interface RAGSearchPanelProps {
  onClose: () => void
  defaultSubject?: string
  passphrase: string
}

interface SearchOptions {
  rerank: boolean
  limit: number
}

// Confidence level based on score
type ConfidenceLevel = 'high' | 'medium' | 'low'

function getConfidenceLevel(score: number): ConfidenceLevel {
  if (score >= 0.8) return 'high'
  if (score >= 0.5) return 'medium'
  return 'low'
}

function getConfidenceColor(level: ConfidenceLevel): string {
  switch (level) {
    case 'high': return 'var(--bp-success, #22c55e)'
    case 'medium': return 'var(--bp-warning, #f59e0b)'
    case 'low': return 'var(--bp-danger, #ef4444)'
  }
}

function getConfidenceLabel(level: ConfidenceLevel): string {
  switch (level) {
    case 'high': return 'Hohe Relevanz'
    case 'medium': return 'Mittlere Relevanz'
    case 'low': return 'Geringe Relevanz'
  }
}

export default function RAGSearchPanel({ onClose, defaultSubject, passphrase }: RAGSearchPanelProps) {
  const [query, setQuery] = useState('')
  const [searching, setSearching] = useState(false)
  const [results, setResults] = useState<EHRAGResult | null>(null)
  const [error, setError] = useState<string | null>(null)

  // Enhanced search options
  const [showAdvancedOptions, setShowAdvancedOptions] = useState(false)
  const [options, setOptions] = useState<SearchOptions>({
    rerank: true,  // Default: enabled for better results
    limit: 5
  })

  const handleSearch = useCallback(async () => {
    if (!query.trim() || !passphrase) return

    setSearching(true)
    setError(null)

    try {
      const result = await ehApi.ragQuery({
        query_text: query,
        passphrase: passphrase,
        subject: defaultSubject,
        limit: options.limit,
        rerank: options.rerank
      })
      setResults(result)
    } catch (err) {
      console.error('RAG search failed:', err)
      setError(err instanceof Error ? err.message : 'Suche fehlgeschlagen')
    } finally {
      setSearching(false)
    }
  }, [query, passphrase, defaultSubject, options])

  const handleKeyDown = (e: React.KeyboardEvent) => {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault()
      handleSearch()
    }
  }

  return (
    <div className="rag-search-overlay">
      <div className="rag-search-modal">
        {/* Header */}
        <div className="rag-search-header">
          <h2>Erwartungshorizont durchsuchen</h2>
          <button className="rag-search-close" onClick={onClose}>&times;</button>
        </div>

        {/* Search Input */}
        <div className="rag-search-input-container">
          <textarea
            className="rag-search-input"
            placeholder="Suchen Sie nach relevanten Abschnitten im Erwartungshorizont..."
            value={query}
            onChange={(e) => setQuery(e.target.value)}
            onKeyDown={handleKeyDown}
            rows={2}
          />
          <button
            className="rag-search-btn"
            onClick={handleSearch}
            disabled={searching || !query.trim()}
          >
            {searching ? 'Sucht...' : 'Suchen'}
          </button>
        </div>

        {/* Advanced Options Toggle */}
        <div className="rag-advanced-toggle">
          <button
            className="rag-toggle-btn"
            onClick={() => setShowAdvancedOptions(!showAdvancedOptions)}
          >
            {showAdvancedOptions ? '▼' : '▶'} Erweiterte Optionen
          </button>
        </div>

        {/* Advanced Options Panel */}
        {showAdvancedOptions && (
          <div className="rag-advanced-options">
            <div className="rag-option-row">
              <label className="rag-option-label">
                <input
                  type="checkbox"
                  checked={options.rerank}
                  onChange={(e) => setOptions(prev => ({ ...prev, rerank: e.target.checked }))}
                />
                <span className="rag-option-text">
                  Re-Ranking aktivieren
                  <span className="rag-option-hint">
                    (Cross-Encoder fuer hoehere Genauigkeit)
                  </span>
                </span>
              </label>
            </div>
            <div className="rag-option-row">
              <label className="rag-option-label">
                Anzahl Ergebnisse:
                <select
                  value={options.limit}
                  onChange={(e) => setOptions(prev => ({ ...prev, limit: Number(e.target.value) }))}
                  className="rag-option-select"
                >
                  <option value={3}>3</option>
                  <option value={5}>5</option>
                  <option value={10}>10</option>
                </select>
              </label>
            </div>
          </div>
        )}

        {/* Error Display */}
        {error && (
          <div className="rag-error">
            {error}
          </div>
        )}

        {/* Results */}
        {results && (
          <div className="rag-results">
            {/* Search Info Badge */}
            {results.search_info && (
              <div className="rag-search-info">
                <span className="rag-info-badge">
                  {results.search_info.rerank_applied && (
                    <span className="rag-info-tag rag-info-rerank">Re-Ranked</span>
                  )}
                  {results.search_info.hybrid_search_applied && (
                    <span className="rag-info-tag rag-info-hybrid">Hybrid Search</span>
                  )}
                  {results.search_info.embedding_model && (
                    <span className="rag-info-tag rag-info-model">
                      {results.search_info.embedding_model.split('/').pop()}
                    </span>
                  )}
                </span>
                <span className="rag-info-count">
                  {results.search_info.total_candidates} Kandidaten gefiltert
                </span>
              </div>
            )}

            {/* Context Summary */}
            {results.context && (
              <div className="rag-context-summary">
                <h4>Zusammengefasster Kontext</h4>
                <p>{results.context}</p>
              </div>
            )}

            {/* Source Results */}
            <div className="rag-sources">
              <h4>Relevante Abschnitte ({results.sources.length})</h4>
              {results.sources.map((source, index) => {
                const confidence = getConfidenceLevel(source.score)
                return (
                  <div key={`${source.eh_id}-${source.chunk_index}`} className="rag-source-item">
                    <div className="rag-source-header">
                      <span className="rag-source-rank">#{index + 1}</span>
                      <span className="rag-source-title">{source.eh_title}</span>
                      <span
                        className="rag-confidence-badge"
                        style={{
                          backgroundColor: getConfidenceColor(confidence),
                          color: 'white'
                        }}
                        title={`Score: ${(source.score * 100).toFixed(1)}%`}
                      >
                        {getConfidenceLabel(confidence)}
                        {source.reranked && <span className="rag-reranked-icon" title="Re-ranked">&#x2713;</span>}
                      </span>
                    </div>
                    <div className="rag-source-text">
                      {source.text}
                    </div>
                    <div className="rag-source-meta">
                      <span>Chunk #{source.chunk_index}</span>
                      <span>Score: {(source.score * 100).toFixed(1)}%</span>
                    </div>
                  </div>
                )
              })}
            </div>
          </div>
        )}

        {/* Empty State */}
        {!results && !error && !searching && (
          <div className="rag-empty-state">
            <div className="rag-empty-icon">&#128269;</div>
            <p>Geben Sie eine Suchanfrage ein, um relevante Abschnitte aus Ihren Erwartungshorizonten zu finden.</p>
            <p className="rag-empty-hint">
              Tipp: Aktivieren Sie "Re-Ranking" fuer praezisere Ergebnisse.
            </p>
          </div>
        )}
      </div>
    </div>
  )
}