import os os.environ["TRANSFORMERS_NO_FAST"] = "1" # Force use of slow tokenizers import io import torch import uvicorn import spacy import pdfplumber import librosa import soundfile as sf import matplotlib.pyplot as plt import numpy as np import json import tempfile from fastapi import FastAPI, UploadFile, File, HTTPException, Form, BackgroundTasks from fastapi.responses import FileResponse, JSONResponse, HTMLResponse from fastapi.middleware.cors import CORSMiddleware from transformers import pipeline, AutoModelForQuestionAnswering, AutoTokenizer from sentence_transformers import SentenceTransformer from pyngrok import ngrok from threading import Thread import time import uuid import subprocess # For running ffmpeg commands import hashlib # For caching file results # For asynchronous blocking calls from starlette.concurrency import run_in_threadpool # Import gensim for topic modeling import gensim from gensim import corpora, models # Import spacy stop words from spacy.lang.en.stop_words import STOP_WORDS # Global cache for analysis results based on file hash analysis_cache = {} # Ensure compatibility with Google Colab try: from google.colab import drive drive.mount('/content/drive') except Exception: pass # Skip drive mount if not in Google Colab # Ensure required directories exist os.makedirs("static", exist_ok=True) os.makedirs("temp", exist_ok=True) # Ensure GPU usage device = "cuda" if torch.cuda.is_available() else "cpu" # Initialize FastAPI app = FastAPI(title="Legal Document and Video Analyzer") # Add CORS middleware app.add_middleware( CORSMiddleware, allow_origins=["*"], allow_credentials=True, allow_methods=["*"], allow_headers=["*"], ) # In-memory storage for document text and chat history document_storage = {} chat_history = [] # Function to store document context by task ID def store_document_context(task_id, text): document_storage[task_id] = text return True # Function to load document context by task ID def load_document_context(task_id): return document_storage.get(task_id, "") # Utility to compute MD5 hash from file content def compute_md5(content: bytes) -> str: return hashlib.md5(content).hexdigest() ############################# # Fine-tuning on CUAD QA # ############################# def fine_tune_cuad_model(): from datasets import load_dataset import numpy as np from transformers import Trainer, TrainingArguments, AutoModelForQuestionAnswering print("✅ Loading CUAD dataset for fine tuning...") dataset = load_dataset("theatticusproject/cuad-qa", trust_remote_code=True) if "train" in dataset: train_dataset = dataset["train"].select(range(50)) if "validation" in dataset: val_dataset = dataset["validation"].select(range(10)) else: split = train_dataset.train_test_split(test_size=0.2) train_dataset = split["train"] val_dataset = split["test"] else: raise ValueError("CUAD dataset does not have a train split") print("✅ Preparing training features...") tokenizer = AutoTokenizer.from_pretrained("deepset/roberta-base-squad2") model = AutoModelForQuestionAnswering.from_pretrained("deepset/roberta-base-squad2") def prepare_train_features(examples): tokenized_examples = tokenizer( examples["question"], examples["context"], truncation="only_second", max_length=384, stride=128, return_overflowing_tokens=True, return_offsets_mapping=True, padding="max_length", ) sample_mapping = tokenized_examples.pop("overflow_to_sample_mapping") offset_mapping = tokenized_examples.pop("offset_mapping") tokenized_examples["start_positions"] = [] tokenized_examples["end_positions"] = [] for i, offsets in enumerate(offset_mapping): input_ids = tokenized_examples["input_ids"][i] cls_index = input_ids.index(tokenizer.cls_token_id) sequence_ids = tokenized_examples.sequence_ids(i) sample_index = sample_mapping[i] answers = examples["answers"][sample_index] if len(answers["answer_start"]) == 0: tokenized_examples["start_positions"].append(cls_index) tokenized_examples["end_positions"].append(cls_index) else: start_char = answers["answer_start"][0] end_char = start_char + len(answers["text"][0]) tokenized_start_index = 0 while sequence_ids[tokenized_start_index] != 1: tokenized_start_index += 1 tokenized_end_index = len(input_ids) - 1 while sequence_ids[tokenized_end_index] != 1: tokenized_end_index -= 1 if not (offsets[tokenized_start_index][0] <= start_char and offsets[tokenized_end_index][1] >= end_char): tokenized_examples["start_positions"].append(cls_index) tokenized_examples["end_positions"].append(cls_index) else: while tokenized_start_index < len(offsets) and offsets[tokenized_start_index][0] <= start_char: tokenized_start_index += 1 tokenized_examples["start_positions"].append(tokenized_start_index - 1) while offsets[tokenized_end_index][1] >= end_char: tokenized_end_index -= 1 tokenized_examples["end_positions"].append(tokenized_end_index + 1) return tokenized_examples print("✅ Tokenizing dataset...") train_dataset = train_dataset.map(prepare_train_features, batched=True, remove_columns=train_dataset.column_names) val_dataset = val_dataset.map(prepare_train_features, batched=True, remove_columns=val_dataset.column_names) train_dataset.set_format(type="torch", columns=["input_ids", "attention_mask", "start_positions", "end_positions"]) val_dataset.set_format(type="torch", columns=["input_ids", "attention_mask", "start_positions", "end_positions"]) training_args = TrainingArguments( output_dir="./fine_tuned_legal_qa", max_steps=1, evaluation_strategy="no", learning_rate=2e-5, per_device_train_batch_size=4, per_device_eval_batch_size=4, num_train_epochs=1, weight_decay=0.01, logging_steps=1, save_steps=1, load_best_model_at_end=False, report_to=[] ) print("✅ Starting fine tuning on CUAD QA dataset...") from transformers import Trainer trainer = Trainer( model=model, args=training_args, train_dataset=train_dataset, eval_dataset=val_dataset, tokenizer=tokenizer, ) trainer.train() print("✅ Fine tuning completed. Saving model...") model.save_pretrained("./fine_tuned_legal_qa") tokenizer.save_pretrained("./fine_tuned_legal_qa") return tokenizer, model ############################# # Load NLP Models # ############################# try: try: nlp = spacy.load("en_core_web_sm") except Exception: spacy.cli.download("en_core_web_sm") nlp = spacy.load("en_core_web_sm") print("✅ Loading NLP models...") # Update summarizer to use facebook/bart-large-cnn for summarization summarizer = pipeline( "summarization", model="facebook/bart-large-cnn", tokenizer="facebook/bart-large-cnn", device=0 if torch.cuda.is_available() else -1 ) if device == "cuda": try: summarizer.model.half() except Exception as e: print("FP16 conversion failed:", e) embedding_model = SentenceTransformer("all-mpnet-base-v2", device=device) ner_model = pipeline("ner", model="dslim/bert-base-NER", device=0 if torch.cuda.is_available() else -1) speech_to_text = pipeline("automatic-speech-recognition", model="openai/whisper-medium", chunk_length_s=30, device_map="auto" if torch.cuda.is_available() else "cpu") if os.path.exists("fine_tuned_legal_qa"): print("✅ Loading fine-tuned CUAD QA model from fine_tuned_legal_qa...") cuad_tokenizer = AutoTokenizer.from_pretrained("fine_tuned_legal_qa") from transformers import AutoModelForQuestionAnswering cuad_model = AutoModelForQuestionAnswering.from_pretrained("fine_tuned_legal_qa") cuad_model.to(device) if device == "cuda": cuad_model.half() else: print("⚠️ Fine-tuned QA model not found. Starting fine tuning on CUAD QA dataset. This may take a while...") cuad_tokenizer, cuad_model = fine_tune_cuad_model() cuad_model.to(device) print("✅ All models loaded successfully") except Exception as e: print(f"⚠️ Error loading models: {str(e)}") raise RuntimeError(f"Error loading models: {str(e)}") from transformers import pipeline qa_model = pipeline("question-answering", model="deepset/roberta-base-squad2") sentiment_pipeline = pipeline("sentiment-analysis", model="distilbert-base-uncased-finetuned-sst-2-english", device=0 if torch.cuda.is_available() else -1) def legal_chatbot(user_input, context): global chat_history chat_history.append({"role": "user", "content": user_input}) response = qa_model(question=user_input, context=context)["answer"] chat_history.append({"role": "assistant", "content": response}) return response def extract_text_from_pdf(pdf_file): try: with pdfplumber.open(pdf_file) as pdf: text = "\n".join([page.extract_text() or "" for page in pdf.pages]) return text.strip() if text else None except Exception as e: raise HTTPException(status_code=400, detail=f"PDF extraction failed: {str(e)}") async def process_video_to_text(video_file_path): try: print(f"Processing video file at {video_file_path}") temp_audio_path = os.path.join("temp", "extracted_audio.wav") cmd = [ "ffmpeg", "-i", video_file_path, "-vn", "-acodec", "pcm_s16le", "-ar", "44100", "-ac", "2", temp_audio_path, "-y" ] await run_in_threadpool(subprocess.run, cmd, check=True) print(f"Audio extracted to {temp_audio_path}") result = await run_in_threadpool(speech_to_text, temp_audio_path) transcript = result["text"] print(f"Transcription completed: {len(transcript)} characters") if os.path.exists(temp_audio_path): os.remove(temp_audio_path) return transcript except Exception as e: print(f"Error in video processing: {str(e)}") raise HTTPException(status_code=400, detail=f"Video processing failed: {str(e)}") async def process_audio_to_text(audio_file_path): try: print(f"Processing audio file at {audio_file_path}") result = await run_in_threadpool(speech_to_text, audio_file_path) transcript = result["text"] print(f"Transcription completed: {len(transcript)} characters") return transcript except Exception as e: print(f"Error in audio processing: {str(e)}") raise HTTPException(status_code=400, detail=f"Audio processing failed: {str(e)}") def extract_named_entities(text): max_length = 10000 entities = [] for i in range(0, len(text), max_length): chunk = text[i:i+max_length] doc = nlp(chunk) entities.extend([{"entity": ent.text, "label": ent.label_} for ent in doc.ents]) return entities # ----------------------------- # Enhanced Risk Analysis Functions # ----------------------------- def analyze_sentiment(text): sentences = [sent.text for sent in nlp(text).sents] if not sentences: return 0 results = sentiment_pipeline(sentences, batch_size=16) scores = [res["score"] if res["label"] == "POSITIVE" else -res["score"] for res in results] avg_sentiment = sum(scores) / len(scores) if scores else 0 return avg_sentiment def analyze_topics(text, num_topics=3): tokens = gensim.utils.simple_preprocess(text, deacc=True) if not tokens: return [] dictionary = corpora.Dictionary([tokens]) corpus = [dictionary.doc2bow(tokens)] lda_model = models.LdaModel(corpus, num_topics=num_topics, id2word=dictionary, passes=10) topics = lda_model.print_topics(num_topics=num_topics) return topics def get_enhanced_context_info(text): enhanced = {} enhanced["average_sentiment"] = analyze_sentiment(text) enhanced["topics"] = analyze_topics(text, num_topics=5) return enhanced # New function to create a detailed, dynamic explanation for each topic def explain_topics(topics): explanation = {} for topic_idx, topic_str in topics: # Split topic string into individual weighted terms parts = topic_str.split('+') terms = [] for part in parts: part = part.strip() if '*' in part: weight_str, word = part.split('*', 1) word = word.strip().strip('\"').strip('\'') try: weight = float(weight_str) except: weight = 0.0 # Filter out common stop words if word.lower() not in STOP_WORDS and len(word) > 1: terms.append((weight, word)) terms.sort(key=lambda x: -x[0]) # Create a plain language label based on dominant words if terms: if any("liability" in word.lower() for weight, word in terms): label = "Liability & Penalty Risk" elif any("termination" in word.lower() for weight, word in terms): label = "Termination & Refund Risk" elif any("compliance" in word.lower() for weight, word in terms): label = "Compliance & Regulatory Risk" else: label = "General Risk Language" else: label = "General Risk Language" explanation_text = ( f"Topic {topic_idx} ({label}) is characterized by dominant terms: " + ", ".join([f"'{word}' ({weight:.3f})" for weight, word in terms[:5]]) ) explanation[topic_idx] = { "label": label, "explanation": explanation_text, "terms": terms } return explanation def analyze_risk_enhanced(text): enhanced = get_enhanced_context_info(text) avg_sentiment = enhanced["average_sentiment"] risk_score = abs(avg_sentiment) if avg_sentiment < 0 else 0 topics_raw = enhanced["topics"] topics_explanation = explain_topics(topics_raw) return { "risk_score": risk_score, "average_sentiment": avg_sentiment, "topics": topics_raw, "topics_explanation": topics_explanation } def analyze_contract_clauses(text): max_length = 512 step = 256 clauses_detected = [] try: clause_types = list(cuad_model.config.id2label.values()) except Exception: clause_types = [ "Obligations of Seller", "Governing Law", "Termination", "Indemnification", "Confidentiality", "Insurance", "Non-Compete", "Change of Control", "Assignment", "Warranty", "Limitation of Liability", "Arbitration", "IP Rights", "Force Majeure", "Revenue/Profit Sharing", "Audit Rights" ] chunks = [text[i:i+max_length] for i in range(0, len(text), step) if i+step < len(text)] for chunk in chunks: inputs = cuad_tokenizer(chunk, return_tensors="pt", truncation=True, max_length=512).to(device) with torch.no_grad(): outputs = cuad_model(**inputs) predictions = torch.sigmoid(outputs.start_logits).cpu().numpy()[0] for idx, confidence in enumerate(predictions): if confidence > 0.5 and idx < len(clause_types): clauses_detected.append({"type": clause_types[idx], "confidence": float(confidence)}) aggregated_clauses = {} for clause in clauses_detected: clause_type = clause["type"] if clause_type not in aggregated_clauses or clause["confidence"] > aggregated_clauses[clause_type]["confidence"]: aggregated_clauses[clause_type] = clause return list(aggregated_clauses.values()) # ----------------------------- # Endpoints # ----------------------------- @app.post("/analyze_legal_document") async def analyze_legal_document(file: UploadFile = File(...)): try: content = await file.read() file_hash = compute_md5(content) if file_hash in analysis_cache: return analysis_cache[file_hash] text = await run_in_threadpool(extract_text_from_pdf, io.BytesIO(content)) if not text: return {"status": "error", "message": "No valid text found in the document."} summary_text = text[:4096] if len(text) > 4096 else text summary = summarizer(summary_text, max_length=200, min_length=50, do_sample=False)[0]['summary_text'] if len(text) > 100 else "Document too short for meaningful summarization." entities = extract_named_entities(text) risk_analysis = analyze_risk_enhanced(text) clauses = analyze_contract_clauses(text) generated_task_id = str(uuid.uuid4()) store_document_context(generated_task_id, text) result = { "status": "success", "task_id": generated_task_id, "summary": summary, "named_entities": entities, "risk_analysis": risk_analysis, "clauses_detected": clauses } analysis_cache[file_hash] = result return result except Exception as e: return {"status": "error", "message": str(e)} @app.post("/analyze_legal_video") async def analyze_legal_video(file: UploadFile = File(...), background_tasks: BackgroundTasks = None): try: content = await file.read() file_hash = compute_md5(content) if file_hash in analysis_cache: return analysis_cache[file_hash] with tempfile.NamedTemporaryFile(delete=False, suffix=os.path.splitext(file.filename)[1]) as temp_file: temp_file.write(content) temp_file_path = temp_file.name text = await process_video_to_text(temp_file_path) if os.path.exists(temp_file_path): os.remove(temp_file_path) if not text: return {"status": "error", "message": "No speech could be transcribed from the video."} transcript_path = os.path.join("static", f"transcript_{int(time.time())}.txt") with open(transcript_path, "w") as f: f.write(text) summary_text = text[:4096] if len(text) > 4096 else text summary = summarizer(summary_text, max_length=200, min_length=50, do_sample=False)[0]['summary_text'] if len(text) > 100 else "Transcript too short for meaningful summarization." entities = extract_named_entities(text) risk_analysis = analyze_risk_enhanced(text) clauses = analyze_contract_clauses(text) generated_task_id = str(uuid.uuid4()) store_document_context(generated_task_id, text) result = { "status": "success", "task_id": generated_task_id, "transcript": text, "transcript_path": transcript_path, "summary": summary, "named_entities": entities, "risk_analysis": risk_analysis, "clauses_detected": clauses } analysis_cache[file_hash] = result return result except Exception as e: return {"status": "error", "message": str(e)} @app.post("/analyze_legal_audio") async def analyze_legal_audio(file: UploadFile = File(...), background_tasks: BackgroundTasks = None): try: content = await file.read() file_hash = compute_md5(content) if file_hash in analysis_cache: return analysis_cache[file_hash] with tempfile.NamedTemporaryFile(delete=False, suffix=os.path.splitext(file.filename)[1]) as temp_file: temp_file.write(content) temp_file_path = temp_file.name text = await process_audio_to_text(temp_audio_path=temp_file_path) if os.path.exists(temp_file_path): os.remove(temp_file_path) if not text: return {"status": "error", "message": "No speech could be transcribed from the audio."} transcript_path = os.path.join("static", f"transcript_{int(time.time())}.txt") with open(transcript_path, "w") as f: f.write(text) summary_text = text[:4096] if len(text) > 4096 else text summary = summarizer(summary_text, max_length=200, min_length=50, do_sample=False)[0]['summary_text'] if len(text) > 100 else "Transcript too short for meaningful summarization." entities = extract_named_entities(text) risk_analysis = analyze_risk_enhanced(text) clauses = analyze_contract_clauses(text) generated_task_id = str(uuid.uuid4()) store_document_context(generated_task_id, text) result = { "status": "success", "task_id": generated_task_id, "transcript": text, "transcript_path": transcript_path, "summary": summary, "named_entities": entities, "risk_analysis": risk_analysis, "clauses_detected": clauses } analysis_cache[file_hash] = result return result except Exception as e: return {"status": "error", "message": str(e)} @app.get("/transcript/{transcript_id}") async def get_transcript(transcript_id: str): transcript_path = os.path.join("static", f"transcript_{transcript_id}.txt") if os.path.exists(transcript_path): return FileResponse(transcript_path) else: raise HTTPException(status_code=404, detail="Transcript not found") @app.post("/legal_chatbot") async def legal_chatbot_api(query: str = Form(...), task_id: str = Form(...)): document_context = load_document_context(task_id) if not document_context: return {"response": "⚠️ No relevant document found for this task ID."} response = legal_chatbot(query, document_context) return {"response": response, "chat_history": chat_history[-5:]} @app.get("/health") async def health_check(): return { "status": "ok", "models_loaded": True, "device": device, "gpu_available": torch.cuda.is_available(), "timestamp": time.time() } def setup_ngrok(): try: auth_token = os.environ.get("NGROK_AUTH_TOKEN") if auth_token: ngrok.set_auth_token(auth_token) ngrok.kill() time.sleep(1) ngrok_tunnel = ngrok.connect(8500, "http") public_url = ngrok_tunnel.public_url print(f"✅ Ngrok Public URL: {public_url}") def keep_alive(): while True: time.sleep(60) try: tunnels = ngrok.get_tunnels() if not tunnels: print("⚠️ Ngrok tunnel closed. Reconnecting...") ngrok_tunnel = ngrok.connect(8500, "http") print(f"✅ Reconnected. New URL: {ngrok_tunnel.public_url}") except Exception as e: print(f"⚠️ Ngrok error: {e}") Thread(target=keep_alive, daemon=True).start() return public_url except Exception as e: print(f"⚠️ Ngrok setup error: {e}") return None # ------------------------------ # Clause Visualization Endpoints # ------------------------------ @app.get("/download_clause_bar_chart") async def download_clause_bar_chart(task_id: str): try: text = load_document_context(task_id) if not text: raise HTTPException(status_code=404, detail="Document context not found") clauses = analyze_contract_clauses(text) if not clauses: raise HTTPException(status_code=404, detail="No clauses detected.") clause_types = [c["type"] for c in clauses] confidences = [c["confidence"] for c in clauses] plt.figure(figsize=(10, 6)) plt.bar(clause_types, confidences, color='blue') plt.xlabel("Clause Type") plt.ylabel("Confidence Score") plt.title("Extracted Legal Clause Confidence Scores") plt.xticks(rotation=45, ha="right") plt.tight_layout() bar_chart_path = os.path.join("static", f"clause_bar_chart_{task_id}.png") plt.savefig(bar_chart_path) plt.close() return FileResponse(bar_chart_path, media_type="image/png", filename=f"clause_bar_chart_{task_id}.png") except Exception as e: raise HTTPException(status_code=500, detail=f"Error generating clause bar chart: {str(e)}") @app.get("/download_clause_donut_chart") async def download_clause_donut_chart(task_id: str): try: text = load_document_context(task_id) if not text: raise HTTPException(status_code=404, detail="Document context not found") clauses = analyze_contract_clauses(text) if not clauses: raise HTTPException(status_code=404, detail="No clauses detected.") from collections import Counter clause_counter = Counter([c["type"] for c in clauses]) labels = list(clause_counter.keys()) sizes = list(clause_counter.values()) plt.figure(figsize=(6, 6)) wedges, texts, autotexts = plt.pie(sizes, labels=labels, autopct='%1.1f%%', startangle=90) centre_circle = plt.Circle((0, 0), 0.70, fc='white') fig = plt.gcf() fig.gca().add_artist(centre_circle) plt.title("Clause Type Distribution") plt.tight_layout() donut_chart_path = os.path.join("static", f"clause_donut_chart_{task_id}.png") plt.savefig(donut_chart_path) plt.close() return FileResponse(donut_chart_path, media_type="image/png", filename=f"clause_donut_chart_{task_id}.png") except Exception as e: raise HTTPException(status_code=500, detail=f"Error generating clause donut chart: {str(e)}") @app.get("/download_clause_radar_chart") async def download_clause_radar_chart(task_id: str): try: text = load_document_context(task_id) if not text: raise HTTPException(status_code=404, detail="Document context not found") clauses = analyze_contract_clauses(text) if not clauses: raise HTTPException(status_code=404, detail="No clauses detected.") labels = [c["type"] for c in clauses] values = [c["confidence"] for c in clauses] labels += labels[:1] values += values[:1] angles = np.linspace(0, 2 * np.pi, len(labels), endpoint=False).tolist() angles += angles[:1] fig, ax = plt.subplots(figsize=(6, 6), subplot_kw=dict(polar=True)) ax.plot(angles, values, 'o-', linewidth=2) ax.fill(angles, values, alpha=0.25) ax.set_thetagrids(np.degrees(angles[:-1]), labels[:-1]) ax.set_title("Legal Clause Radar Chart", y=1.1) radar_chart_path = os.path.join("static", f"clause_radar_chart_{task_id}.png") plt.savefig(radar_chart_path) plt.close() return FileResponse(radar_chart_path, media_type="image/png", filename=f"clause_radar_chart_{task_id}.png") except Exception as e: raise HTTPException(status_code=500, detail=f"Error generating clause radar chart: {str(e)}") def run(): print("Starting FastAPI server...") uvicorn.run(app, host="0.0.0.0", port=8500, timeout_keep_alive=600) if __name__ == "__main__": public_url = setup_ngrok() if public_url: print(f"\n✅ Your API is publicly available at: {public_url}/docs\n") else: print("\n⚠️ Ngrok setup failed. API will only be available locally.\n") run()