import json
from django.http import JsonResponse
from django.views.decorators.http import require_http_methods
from django.shortcuts import get_object_or_404
from file.models import File

@require_http_methods(["GET"])
def get_file_content(request, file_id):
    """Get the text content of a specific file."""
    file_obj = get_object_or_404(File, id=file_id, user=request.quiz_user)
    return JsonResponse({
        'id': file_obj.id,
        'name': file_obj.name,
        'content': file_obj.text
    })

@require_http_methods(["POST"])
def save_file_content(request, file_id):
    """Save updated text content to a file."""
    file_obj = get_object_or_404(File, id=file_id, user=request.quiz_user)
    try:
        data = json.loads(request.body)
        new_content = data.get('content', '')
        file_obj.text = new_content
        file_obj.save()
        return JsonResponse({'success': True})
    except (json.JSONDecodeError, KeyError):
        return JsonResponse({'success': False, 'error': 'Invalid data'}, status=400)


from django.http import FileResponse

def serve_pdf_api(request, file_id):
    """Serve the raw PDF file for viewing."""
    file_obj = get_object_or_404(File, id=file_id, user=request.quiz_user)
    
    if not file_obj.mime_type == 'application/pdf' or not file_obj.file_content:
        return JsonResponse({'error': 'Not a PDF file'}, status=400)
    
    response = FileResponse(
        file_obj.file_content.open('rb'),
        content_type='application/pdf'
    )
    # Add CORS headers to allow CDN-hosted PDF.js viewer to fetch the PDF
    response['Access-Control-Allow-Origin'] = '*'
    response['Access-Control-Allow-Methods'] = 'GET, OPTIONS'
    response['Access-Control-Allow-Headers'] = 'Content-Type'
    return response