from flask import Flask, render_template_string, request, jsonify import pdfplumber import re from collections import Counter import logging import os from werkzeug.utils import secure_filename app = Flask(__name__) app.config['MAX_CONTENT_LENGTH'] = 16 * 1024 * 1024 # 16MB max file size app.config['UPLOAD_FOLDER'] = 'temp_uploads' logging.basicConfig(level=logging.INFO) # Create upload folder if it doesn't exist os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True) # KS2 writing standards criteria KS2_CRITERIA = { 'punctuation': { 'expected': [':', ';', ',', '.', '(', ')', '!', '?', '"', "'"], 'weight': 0.2 }, 'sentence_structure': { 'min_words_per_sentence': 8, 'max_words_per_sentence': 25, 'weight': 0.2 }, 'vocabulary': { 'advanced_words': set([ 'although', 'however', 'nevertheless', 'furthermore', 'moreover', 'consequently', 'therefore', 'meanwhile', 'subsequently', 'despite' ]), 'weight': 0.2 }, 'paragraphing': { 'min_sentences_per_paragraph': 3, 'weight': 0.2 }, 'text_length': { 'min_words': 200, 'weight': 0.2 } } def allowed_file(filename): return '.' in filename and filename.rsplit('.', 1)[1].lower() == 'pdf' def extract_text_from_pdf(pdf_file): """Extract text from PDF with error handling""" text = "" temp_path = None try: # Save the file temporarily filename = secure_filename(pdf_file.filename) temp_path = os.path.join(app.config['UPLOAD_FOLDER'], filename) pdf_file.save(temp_path) # Extract text with pdfplumber.open(temp_path) as pdf: for page in pdf.pages: extracted_text = page.extract_text() if extracted_text: text += extracted_text + "\n" if not text.strip(): raise ValueError("No text could be extracted from the PDF") return text.strip() except Exception as e: logging.error(f"PDF extraction error: {str(e)}") raise finally: # Clean up temporary file if temp_path and os.path.exists(temp_path): try: os.remove(temp_path) except Exception as e: logging.error(f"Error removing temporary file: {str(e)}") def clean_text(text): """Clean and normalize text""" # Remove excessive whitespace text = re.sub(r'\s+', ' ', text) # Normalize quotes text = text.replace('"', '"').replace('"', '"') # Normalize apostrophes text = text.replace(''', "'").replace(''', "'") return text.strip() def analyze_text(text): """Analyze text with improved error handling and validation""" try: # Clean the text text = clean_text(text) # Basic validation if not text: raise ValueError("No text provided for analysis") # Split into paragraphs, sentences, and words paragraphs = [p.strip() for p in text.split('\n\n') if p.strip()] sentences = [s.strip() for s in re.split(r'[.!?]+', text) if s.strip()] words = [w.lower() for w in re.findall(r'\b\w+\b', text)] if not sentences: raise ValueError("No valid sentences found in the text") # Initialize scores and improvements scores = {} improvements = [] # Check text length word_count = len(words) scores['text_length'] = min(word_count / KS2_CRITERIA['text_length']['min_words'], 1.0) if word_count < KS2_CRITERIA['text_length']['min_words']: improvements.append(f"Text length ({word_count} words) is below the expected {KS2_CRITERIA['text_length']['min_words']} words - try to write more") # Check punctuation punct_count = sum(1 for char in text if char in KS2_CRITERIA['punctuation']['expected']) punct_variety = len(set(char for char in text if char in KS2_CRITERIA['punctuation']['expected'])) scores['punctuation'] = min(punct_variety / len(KS2_CRITERIA['punctuation']['expected']), 1.0) if scores['punctuation'] < 0.7: missing_punct = [p for p in KS2_CRITERIA['punctuation']['expected'] if p not in text] improvements.append(f"Try using more varied punctuation. Consider using: {', '.join(missing_punct[:3])}") # Check sentence structure avg_words_per_sentence = len(words) / len(sentences) if sentences else 0 scores['sentence_structure'] = 1.0 if ( KS2_CRITERIA['sentence_structure']['min_words_per_sentence'] <= avg_words_per_sentence <= KS2_CRITERIA['sentence_structure']['max_words_per_sentence'] ) else 0.5 if scores['sentence_structure'] < 1.0: if avg_words_per_sentence < KS2_CRITERIA['sentence_structure']['min_words_per_sentence']: improvements.append("Try writing longer, more detailed sentences") else: improvements.append("Some sentences may be too long - try breaking them up") # Check vocabulary advanced_words_used = sum(1 for word in words if word in KS2_CRITERIA['vocabulary']['advanced_words']) scores['vocabulary'] = min(advanced_words_used / 5, 1.0) if scores['vocabulary'] < 0.7: unused_advanced_words = [word for word in KS2_CRITERIA['vocabulary']['advanced_words'] if word not in words][:3] improvements.append(f"Include more advanced connecting words such as: {', '.join(unused_advanced_words)}") # Calculate final score with validation total_score = sum( scores[criterion] * KS2_CRITERIA[criterion]['weight'] for criterion in scores ) if not 0 <= total_score <= 1: raise ValueError(f"Invalid total score calculated: {total_score}") meets_standard = total_score >= 0.7 return { 'meets_standard': meets_standard, 'score': round(total_score * 100, 1), 'improvements': improvements[:3], 'detailed_scores': {k: round(v * 100, 1) for k, v in scores.items()}, 'stats': { 'word_count': word_count, 'sentence_count': len(sentences), 'paragraph_count': len(paragraphs), 'avg_words_per_sentence': round(avg_words_per_sentence, 1) } } except Exception as e: logging.error(f"Analysis error: {str(e)}") raise # Enhanced HTML template with error handling and loading state HTML_TEMPLATE = """ KS2 Writing Assessment Tool

KS2 Writing Assessment Tool

Analyzing document... Please wait...
{% if error %}
{{ error }}
{% endif %} {% if result %}

This writing is {% if result.meets_standard %} at the expected standard {% else %} working towards the expected standard {% endif %} for Key Stage 2 (Overall Score: {{ result.score }}%)

Detailed Scores:

    {% for criterion, score in result.detailed_scores.items() %}
  • {{ criterion|title }}: {{ score }}%
    • {% endfor %}

Text Statistics:

    {% for stat, value in result.stats.items() %}
  • {{ stat|replace('_', ' ')|title }}: {{ value }}
    • {% endfor %}
{% if result.improvements %}

Ways to improve:

    {% for improvement in result.improvements %}
  • {{ improvement }}
    • {% endfor %}
{% endif %}
{% endif %}
""" @app.route('/', methods=['GET', 'POST']) def index(): error = None result = None if request.method == 'POST': try: if 'pdf' not in request.files: raise ValueError('No file uploaded') pdf_file = request.files['pdf'] if pdf_file.filename == '': raise ValueError('No file selected') if not allowed_file(pdf_file.filename): raise ValueError('Invalid file type. Please upload a PDF file') text = extract_text_from_pdf(pdf_file) result = analyze_text(text) except Exception as e: error = str(e) logging.error(f"Error processing request: {str(e)}") return render_template_string(HTML_TEMPLATE, result=result, error=error) if __name__ == '__main__': app.run(debug=True)