app.py

import os
import gradio as gr
from transformers import pipeline
import spacy
import subprocess
import nltk
from nltk.corpus import wordnet
from textblob import TextBlob
from pattern.en import conjugate, lemma, pluralize, singularize
from gector.gec_model import GecBERTModel  # Import GECToR Model
from utils.helpers import read_lines, normalize  # GECToR utilities

# Initialize the English text classification pipeline for AI detection
pipeline_en = pipeline(task="text-classification", model="Hello-SimpleAI/chatgpt-detector-roberta")

# Function to predict the label and score for English text (AI Detection)
def predict_en(text):
    res = pipeline_en(text)[0]
    return res['label'], res['score']

# Ensure necessary NLTK data is downloaded for Humanifier
nltk.download('wordnet')
nltk.download('omw-1.4')

# Ensure the SpaCy model is installed for Humanifier
try:
    nlp = spacy.load("en_core_web_sm")
except OSError:
    subprocess.run(["python", "-m", "spacy", "download", "en_core_web_sm"])
    nlp = spacy.load("en_core_web_sm")

# Function to get synonyms using NLTK WordNet (Humanifier)
def get_synonyms_nltk(word, pos):
    synsets = wordnet.synsets(word, pos=pos)
    if synsets:
        lemmas = synsets[0].lemmas()
        return [lemma.name() for lemma in lemmas]
    return []

# Function to capitalize the first letter of sentences and proper nouns (Humanifier)
def capitalize_sentences_and_nouns(text):
    doc = nlp(text)
    corrected_text = []

    for sent in doc.sents:
        sentence = []
        for token in sent:
            if token.i == sent.start:  # First word of the sentence
                sentence.append(token.text.capitalize())
            elif token.pos_ == "PROPN":  # Proper noun
                sentence.append(token.text.capitalize())
            else:
                sentence.append(token.text)
        corrected_text.append(' '.join(sentence))

    return ' '.join(corrected_text)

# Function to correct tense errors using Pattern
def correct_tense_errors(text):
    doc = nlp(text)
    corrected_text = []
    
    for token in doc:
        if token.pos_ == "VERB":
            # Use conjugate from Pattern to adjust the tense of the verb
            verb_form = conjugate(lemma(token.text), tense='past')  # Example: fix to past tense
            corrected_text.append(verb_form)
        else:
            corrected_text.append(token.text)
    
    return ' '.join(corrected_text)

# Function to correct singular/plural errors using Pattern
def correct_singular_plural_errors(text):
    doc = nlp(text)
    corrected_text = []

    for token in doc:
        if token.pos_ == "NOUN":
            if token.tag_ == "NN":  # Singular noun
                corrected_text.append(singularize(token.text))
            elif token.tag_ == "NNS":  # Plural noun
                corrected_text.append(pluralize(token.text))
        else:
            corrected_text.append(token.text)

    return ' '.join(corrected_text)

# Function to correct overall grammar using TextBlob
def correct_grammar_textblob(text):
    blob = TextBlob(text)
    corrected_text = str(blob.correct())  # TextBlob's built-in grammar correction
    return corrected_text

# Initialize GECToR Model for Grammar Correction
def load_gector_model():
    model_path = ["gector/roberta_1_gector.th"]  # Ensure model file is placed correctly
    vocab_path = "output_vocabulary"
    model = GecBERTModel(vocab_path=vocab_path,
                         model_paths=model_path,
                         max_len=50,
                         min_len=3,
                         iterations=5,
                         min_error_probability=0.0,
                         lowercase_tokens=0,
                         model_name="roberta",
                         special_tokens_fix=1,
                         log=False,
                         confidence=0,
                         del_confidence=0,
                         is_ensemble=False,
                         weigths=None)
    return model

# Load the GECToR model
gector_model = load_gector_model()

# Function to correct grammar using GECToR
def correct_grammar_gector(text):
    sentences = [text.split()]
    corrected_sentences, _ = gector_model.handle_batch(sentences)
    return " ".join(corrected_sentences[0])

# Paraphrasing function using SpaCy and NLTK (Humanifier)
def paraphrase_with_spacy_nltk(text):
    doc = nlp(text)
    paraphrased_words = []
    
    for token in doc:
        # Map SpaCy POS tags to WordNet POS tags
        pos = None
        if token.pos_ in {"NOUN"}:
            pos = wordnet.NOUN
        elif token.pos_ in {"VERB"}:
            pos = wordnet.VERB
        elif token.pos_ in {"ADJ"}:
            pos = wordnet.ADJ
        elif token.pos_ in {"ADV"}:
            pos = wordnet.ADV
        
        synonyms = get_synonyms_nltk(token.text.lower(), pos) if pos else []
        
        # Replace with a synonym only if it makes sense
        if synonyms and token.pos_ in {"NOUN", "VERB", "ADJ", "ADV"} and synonyms[0] != token.text.lower():
            paraphrased_words.append(synonyms[0])
        else:
            paraphrased_words.append(token.text)
    
    return ' '.join(paraphrased_words)

# Combined function: Paraphrase -> Grammar Correction -> Capitalization (Humanifier)
def paraphrase_and_correct(text):
    # Step 1: Paraphrase the text
    paraphrased_text = paraphrase_with_spacy_nltk(text)
    
    # Step 2: Apply grammatical corrections using GECToR
    corrected_text = correct_grammar_gector(paraphrased_text)
    
    return corrected_text

# Gradio app setup with two tabs
with gr.Blocks() as demo:
    with gr.Tab("AI Detection"):
        t1 = gr.Textbox(lines=5, label='Text')
        button1 = gr.Button("🤖 Predict!")
        label1 = gr.Textbox(lines=1, label='Predicted Label 🎃')
        score1 = gr.Textbox(lines=1, label='Prob')

        button1.click(predict_en, inputs=[t1], outputs=[label1, score1], api_name='predict_en')
    
    with gr.Tab("Humanifier"):
        text_input = gr.Textbox(lines=5, label="Input Text")
        paraphrase_button = gr.Button("Paraphrase & Correct")
        output_text = gr.Textbox(label="Paraphrased and Corrected Text")

        paraphrase_button.click(paraphrase_and_correct, inputs=text_input, outputs=output_text)

# Launch the app
demo.launch()