story-generator/src/components/exercises/SentenceCompletion.tsx

import React, { useState, useRef } from 'react';
import { supabase } from '../../lib/supabase';
import { Loader2 } from 'lucide-react';
import { useStudentTracking } from '../../hooks/useStudentTracking';

interface SentenceCompletionProps {
  story: {
    id: string;
    content: {
      pages: Array<{
        text: string;
      }>;
    };
  };
  studentId: string;
  onComplete?: (score: number) => void;
}

export function SentenceCompletion({ story, studentId, onComplete }: SentenceCompletionProps) {
  const [currentSentence, setCurrentSentence] = useState(0);
  const [userAnswer, setUserAnswer] = useState('');
  const [score, setScore] = useState(0);
  const [isSubmitting, setIsSubmitting] = useState(false);
  const [exerciseSentences, setExerciseSentences] = useState<Array<{
    sentence: string;
    answer: string;
  }>>([]);
  const [isLoading, setIsLoading] = useState(true);
  const { trackExerciseCompleted } = useStudentTracking();
  const startTime = useRef(Date.now());
  const correctAnswers = useRef(0);

  // Carregar palavras e preparar sentenças
  React.useEffect(() => {
    const loadExerciseWords = async () => {
      try {
        const { data: words, error } = await supabase
          .from('story_exercise_words')
          .select('*')
          .eq('story_id', story.id)
          .eq('exercise_type', 'completion');

        if (error) throw error;

        // Extrair todas as sentenças do texto
        const allSentences = story.content.pages
          .map(page => page.text.split(/[.!?]+/))
          .flat()
          .filter(Boolean)
          .map(sentence => sentence.trim());

        // Preparar exercícios com as palavras do banco
        const exercises = allSentences
          .filter(sentence => 
            words?.some(word => 
              sentence.toLowerCase().includes(word.word.toLowerCase())
            )
          )
          .map(sentence => {
            const word = words?.find(w => 
              sentence.toLowerCase().includes(w.word.toLowerCase())
            );
            return {
              sentence: sentence.replace(
                new RegExp(word?.word || '', 'i'),
                '_____'
              ),
              answer: word?.word || ''
            };
          })
          .filter(exercise => exercise.answer); // Remover exercícios sem resposta

        setExerciseSentences(exercises);
        setIsLoading(false);
      } catch (error) {
        console.error('Erro ao carregar palavras:', error);
        setIsLoading(false);
      }
    };

    loadExerciseWords();
  }, [story.id, story.content.pages]);

  if (isLoading) {
    return (
      <div className="max-w-2xl mx-auto p-6">
        <div className="animate-pulse">
          <div className="h-8 bg-gray-200 rounded w-1/3 mb-6" />
          <div className="h-64 bg-gray-200 rounded" />
        </div>
      </div>
    );
  }

  if (!exerciseSentences.length) {
    return (
      <div className="max-w-2xl mx-auto p-6">
        <p className="text-gray-600">
          Não foi possível gerar exercícios para este texto.
        </p>
      </div>
    );
  }

  const currentExercise = exerciseSentences[currentSentence];

  const handleSubmit = async () => {
    setIsSubmitting(true);
    try {
      const isCorrect = userAnswer.toLowerCase() === currentExercise.answer.toLowerCase();
      
      if (isCorrect) {
        setScore(prev => prev + 10);
        correctAnswers.current += 1;
      }

      // Avançar para próxima sentença ou finalizar
      if (currentSentence < exerciseSentences.length - 1) {
        setCurrentSentence(prev => prev + 1);
        setUserAnswer('');
      } else {
        // Track exercise completion
        const timeSpent = Date.now() - startTime.current;
        trackExerciseCompleted({
          exercise_id: `${story.id}_completion`,
          story_id: story.id,
          student_id: studentId,
          exercise_type: 'completion',
          score: Math.floor((correctAnswers.current / exerciseSentences.length) * 100),
          time_spent: timeSpent,
          answers_correct: correctAnswers.current,
          answers_total: exerciseSentences.length,
          difficulty_level: exerciseSentences.length <= 5 ? 'easy' : exerciseSentences.length <= 10 ? 'medium' : 'hard'
        });

        if (onComplete) {
          onComplete(Math.floor((correctAnswers.current / exerciseSentences.length) * 100));
        }
      }

    } catch (error) {
      console.error('Erro ao verificar resposta:', error);
    } finally {
      setIsSubmitting(false);
    }
  };

  return (
    <div className="max-w-2xl mx-auto p-6">
      <h2 className="text-2xl font-bold text-gray-900 mb-6">
        Complete a Frase
      </h2>

      {/* Progresso */}
      <div className="mb-6">
        <div className="flex justify-between text-sm text-gray-500">
          <span>Questão {currentSentence + 1} de {exerciseSentences.length}</span>
          <span>{score} pontos</span>
        </div>
        <div className="mt-2 h-2 bg-gray-200 rounded-full overflow-hidden">
          <div 
            className="h-full bg-purple-600 transition-all"
            style={{ width: `${((currentSentence + 1) / exerciseSentences.length) * 100}%` }}
          />
        </div>
      </div>

      {/* Sentença atual */}
      <div className="mb-8">
        <p className="text-xl leading-relaxed text-gray-700">
          {currentExercise.sentence}
        </p>
      </div>

      {/* Campo de resposta */}
      <div className="mb-8">
        <input
          type="text"
          value={userAnswer}
          onChange={(e) => setUserAnswer(e.target.value)}
          placeholder="Digite a palavra que completa a frase..."
          className="w-full px-4 py-3 text-lg border border-gray-300 rounded-lg
            focus:outline-none focus:ring-2 focus:ring-purple-500"
        />
      </div>

      {/* Botão de verificação */}
      <button
        onClick={handleSubmit}
        disabled={!userAnswer || isSubmitting}
        className="w-full py-3 bg-purple-600 text-white rounded-lg font-medium
          hover:bg-purple-700 disabled:bg-gray-300 disabled:cursor-not-allowed
          transition-colors"
      >
        {isSubmitting ? (
          <Loader2 className="w-5 h-5 animate-spin mx-auto" />
        ) : (
          'Verificar'
        )}
      </button>
    </div>
  );
}