import { NextRequest, NextResponse } from 'next/server';
import { GeneratedQuestion } from '@/types/quiz';

export async function PUT(req: NextRequest) {
  try {
    const updatedQuestion: GeneratedQuestion = await req.json();

    // Validate the question structure
    if (!updatedQuestion.id || !updatedQuestion.stem || !updatedQuestion.content) {
      return NextResponse.json(
        { error: 'Invalid question data' },
        { status: 400 }
      );
    }

    // Validate required fields
    const { Question, Options, Answer } = updatedQuestion.content;
    if (!Question || !Options || !Answer) {
      return NextResponse.json(
        { error: 'Missing required question content' },
        { status: 400 }
      );
    }

    // Validate options structure
    const requiredOptions = ['A', 'B', 'C', 'D'];
    for (const option of requiredOptions) {
      if (!Options[option as keyof typeof Options]) {
        return NextResponse.json(
          { error: `Missing option ${option}` },
          { status: 400 }
        );
      }
    }

    // Validate answer is one of the options
    if (!requiredOptions.includes(Answer)) {
      return NextResponse.json(
        { error: 'Invalid answer option' },
        { status: 400 }
      );
    }

    // Validate points is a positive number
    if (typeof updatedQuestion.points !== 'number' || updatedQuestion.points < 1) {
      return NextResponse.json(
        { error: 'Points must be a positive number' },
        { status: 400 }
      );
    }

    // In a real application, you would save this to a database
    // For now, we'll just return the validated question
    // Note: We preserve the original type and points as they shouldn't be modified
    const validatedQuestion: GeneratedQuestion = {
      ...updatedQuestion,
      // Preserve original type and points (these should not be modified)
      type: updatedQuestion.type, // Keep original type
      points: updatedQuestion.points, // Keep original points
      // Ensure the content.Question matches the stem for consistency
      content: {
        ...updatedQuestion.content,
        Question: updatedQuestion.stem,
      },
      // Update the timestamp to reflect the edit
      createdAt: new Date(),
    };

    return NextResponse.json(validatedQuestion);

  } catch (error) {
    console.error('Error updating question:', error);
    return NextResponse.json(
      { error: 'Failed to update question' },
      { status: 500 }
    );
  }
}