import json
from difflib import SequenceMatcher
from transformers import T5Tokenizer, T5ForConditionalGeneration
from transformers.utils import logging as hf_logging

hf_logging.set_verbosity_error()

MODEL_DIR = "t5-viet-qg-finetuned"
DATA_PATH = "30ktrain.json"

tokenizer = T5Tokenizer.from_pretrained(MODEL_DIR)
model = T5ForConditionalGeneration.from_pretrained(MODEL_DIR)

def find_best_match_from_context(user_context, squad_data):
    best_score, best_entry = 0.0, None
    ui = user_context.lower()

    for article in squad_data.get("data", []):
        context_title = article.get("title", "")
        score_title = SequenceMatcher(None, ui, context_title.lower()).ratio()

        for paragraph in article.get("paragraphs", []):
            context = paragraph.get("context", "")
            for qa in paragraph.get("qas", []):
                answers = qa.get("answers", [])
                if not answers:
                    continue
                answer_text = answers[0].get("text", "").strip()
                question_text = qa.get("question", "").strip()

                score = score_title
                if score > best_score:
                    best_score = score
                    best_entry = (context, answer_text, question_text)

    return best_entry

def _near_duplicate(q, seen, thr=0.90):
    for s in seen:
        if SequenceMatcher(None, q, s).ratio() >= thr:
            return True
    return False

def generate_questions(user_context,
                       total_questions=20,
                       batch_size=10,
                       top_k=60,
                       top_p=0.95,
                       temperature=0.9,  
                       max_input_len=512,
                       max_new_tokens=64):
    with open(DATA_PATH, "r", encoding="utf-8") as f:
        squad_data = json.load(f)

    best_entry = find_best_match_from_context(user_context, squad_data)
    if best_entry is None:
        print("Không tìm thấy dữ liệu phù hợp trong file JSON.")
        return

    context, answer, _ = best_entry

   
    input_text = f"answer: {answer}\ncontext: {context}\nquestion:"
    inputs = tokenizer(
        input_text,
        return_tensors="pt",
        truncation=True,
        max_length=max_input_len
    )

    unique_questions = []
    remaining = total_questions

    while remaining > 0:
        n = min(batch_size, remaining)
        outputs = model.generate(
            **inputs,
            do_sample=True,
            top_k=top_k,  
            top_p=top_p,  
            temperature=temperature,  
            max_new_tokens=max_new_tokens,
            num_return_sequences=n,
            no_repeat_ngram_size=3,
            repetition_penalty=1.12
        )

        for out in outputs:
            q = tokenizer.decode(out, skip_special_tokens=True).strip()
            if len(q) < 5:
                continue
            if not _near_duplicate(q, unique_questions, thr=0.90):
                unique_questions.append(q)

        remaining = total_questions - len(unique_questions)
        if remaining <= 0:
            break

    unique_questions = unique_questions[:total_questions]

    
    print("Các câu hỏi mới được sinh ra:")
    for i, q in enumerate(unique_questions, 1):
        if not q.endswith("?"):
            q += "?"  
        print(f"{i}. {q}")

if __name__ == "__main__":
    user_context = input("\nNhập đoạn văn bản:\n ").strip()

    raw_n = input("\nNhập vào số lượng câu hỏi bạn cần:").strip()
    if raw_n == "":
        total_questions = 20
    else:
        try:
            total_questions = int(raw_n)
        except ValueError:
            print("Giá trị không hợp lệ. Dùng mặc định 20.")
            total_questions = 20

    if total_questions < 1:
        total_questions = 1
    if total_questions > 200:
        total_questions = 200

    batch_size = 20 if total_questions >= 30 else min(20, total_questions)

    print("\nĐang phân tích dữ liệu...\n")

    generate_questions(
        user_context=user_context,
        total_questions=total_questions,
        batch_size=batch_size,
        top_k=60,
        top_p=0.95,  
        temperature=0.9,  
        max_input_len=512,
        max_new_tokens=64
    )