app.py

import gradio as gr
import torch
from transformers import DebertaV2Model, DebertaV2Config, AutoTokenizer, PreTrainedModel
from transformers.models.deberta.modeling_deberta import ContextPooler
from transformers import pipeline, AutoModelForSequenceClassification
import torch.nn as nn

# Define the model and tokenizer
model_card = "microsoft/mdeberta-v3-base"
subjectivity_only_model = "MatteoFasulo/mdeberta-v3-base-subjectivity-multilingual-no-arabic"
sentiment_model = "MatteoFasulo/mdeberta-v3-base-subjectivity-sentiment-multilingual-no-arabic"

# Define some examples for the Gradio interface (cached to run on-the-fly)
examples = [
    ["But then Trump came to power and sidelined the defense hawks, ushering in a dramatic shift in Republican sentiment toward America's allies and adversaries."],
    ["Boxing Day ambush & flagship attack Putin has long tried to downplay the true losses his army has faced in the Black Sea."],
]

class CustomModel(PreTrainedModel):
    config_class = DebertaV2Config
    def __init__(self, config, sentiment_dim=3, num_labels=2, *args, **kwargs):
        super().__init__(config, *args, **kwargs)
        self.deberta = DebertaV2Model(config)
        self.pooler = ContextPooler(config)
        output_dim = self.pooler.output_dim
        self.dropout = nn.Dropout(0.1)
        self.classifier = nn.Linear(output_dim + sentiment_dim, num_labels)

    def forward(self, input_ids, positive, neutral, negative, token_type_ids=None, attention_mask=None, labels=None):
        outputs = self.deberta(input_ids=input_ids, attention_mask=attention_mask)
        encoder_layer = outputs[0]
        pooled_output = self.pooler(encoder_layer)
        sentiment_features = torch.stack((positive, neutral, negative), dim=1).to(pooled_output.dtype)
        combined_features = torch.cat((pooled_output, sentiment_features), dim=1)
        logits = self.classifier(self.dropout(combined_features))
        return {'logits': logits}

def load_tokenizer(model_name: str):
    return AutoTokenizer.from_pretrained(model_name)

load_model_cache = {} 
def load_model(model_name: str):
    if model_name not in load_model_cache:
        print(f"Loading model: {model_name}")
        if 'sentiment' in model_name:
            config = DebertaV2Config.from_pretrained(
                model_name, num_labels=2, id2label={0: 'OBJ', 1: 'SUBJ'}, label2id={'OBJ': 0, 'SUBJ': 1},
                output_attentions=False, output_hidden_states=False
            )
            model_instance = CustomModel(config=config, sentiment_dim=3, num_labels=2).from_pretrained(model_name)
        else:
            model_instance = AutoModelForSequenceClassification.from_pretrained(
                model_name, num_labels=2, id2label={0: 'OBJ', 1: 'SUBJ'}, label2id={'OBJ': 0, 'SUBJ': 1},
                output_attentions=False, output_hidden_states=False
            )
        load_model_cache[model_name] = model_instance
    return load_model_cache[model_name]

sentiment_pipeline_cache = None # 
def get_sentiment_values(text: str):
    global sentiment_pipeline_cache
    if sentiment_pipeline_cache is None:
        print("Loading sentiment pipeline...")
        sentiment_pipeline_cache = pipeline(
            "sentiment-analysis",
            model="cardiffnlp/twitter-xlm-roberta-base-sentiment",
            tokenizer="cardiffnlp/twitter-xlm-roberta-base-sentiment",
            top_k=None
        )
    sentiments_output = sentiment_pipeline_cache(text)
    if sentiments_output and isinstance(sentiments_output, list) and sentiments_output[0]:
        sentiments = sentiments_output[0]
        return {s['label'].lower(): s['score'] for s in sentiments}
    return {} 


def analyze(text):
    if not text or not text.strip():
        empty_data = [
            ["Positive", ""], ["Neutral", ""], ["Negative", ""],
            ["Sent-Subj OBJ", ""], ["Sent-Subj SUBJ", ""],
            ["TextOnly OBJ", ""], ["TextOnly SUBJ", ""]
        ]
        return empty_data

    sentiment_values = get_sentiment_values(text)
    tokenizer = load_tokenizer(model_card)
    model_with_sentiment = load_model(sentiment_model)
    model_without_sentiment = load_model(subjectivity_only_model)

    inputs_dict = tokenizer(text, padding=True, truncation=True, max_length=256, return_tensors='pt')
    
    device = next(model_without_sentiment.parameters()).device 
    inputs_dict_on_device = {k: v.to(device) for k, v in inputs_dict.items()}

    outputs_base = model_without_sentiment(**inputs_dict_on_device)
    logits_base = outputs_base.get('logits')
    prob_base = torch.nn.functional.softmax(logits_base, dim=1)[0]

    positive = sentiment_values.get('positive', 0.0)
    neutral = sentiment_values.get('neutral', 0.0)
    negative = sentiment_values.get('negative', 0.0)

    
    current_inputs_for_sentiment_model = inputs_dict_on_device.copy()
    current_inputs_for_sentiment_model['positive'] = torch.tensor(positive, device=device).unsqueeze(0).float()
    current_inputs_for_sentiment_model['neutral'] = torch.tensor(neutral, device=device).unsqueeze(0).float()
    current_inputs_for_sentiment_model['negative'] = torch.tensor(negative, device=device).unsqueeze(0).float()


    outputs_sentiment = model_with_sentiment(**current_inputs_for_sentiment_model)
    logits_sentiment = outputs_sentiment.get('logits')
    prob_sentiment = torch.nn.functional.softmax(logits_sentiment, dim=1)[0]

    table_data = [
        ["Positive", f"{positive:.2%}"],
        ["Neutral", f"{neutral:.2%}"],
        ["Negative", f"{negative:.2%}"],
        ["Sent-Subj OBJ", f"{prob_sentiment[0]:.2%}"],
        ["Sent-Subj SUBJ", f"{prob_sentiment[1]:.2%}"],
        ["TextOnly OBJ", f"{prob_base[0]:.2%}"],
        ["TextOnly SUBJ", f"{prob_base[1]:.2%}"]
    ]
    return table_data

def load_default_example_on_startup():
    print("Loading default example on startup...")
    if examples and examples[0] and isinstance(examples[0], list) and examples[0]:
        default_text = examples[0][0]
        default_analysis_results = analyze(default_text)
        return default_text, default_analysis_results
    print("Warning: No valid default example found. Loading empty.")
    empty_text = ""
    empty_results = analyze(empty_text) 
    return empty_text, empty_results

with gr.Blocks(theme=gr.themes.Ocean(), title="Subjectivity & Sentiment Dashboard") as demo:
    gr.Markdown("# 🚀 Subjectivity & Sentiment Analysis Dashboard 🚀")

    with gr.Column():
        txt = gr.Textbox(
            label="Enter text to analyze",
            placeholder="Paste news sentence here...",
            lines=2,
        )
        with gr.Row():
            gr.Column(scale=1, min_width=0) 
            btn = gr.Button(
                "Analyze 🔍",
                variant="primary",
                size="md",
                scale=0
            )

    with gr.Tabs():
        with gr.TabItem("Raw Scores 📋"):
            table = gr.Dataframe(
                headers=["Metric", "Value"],
                datatype=["str", "str"],
                interactive=False
            )
        with gr.TabItem("About ℹ️"):
            gr.Markdown(
                "This dashboard uses two DeBERTa-based models (with and without sentiment integration) "
                "to detect subjectivity, alongside sentiment scores from an XLM-RoBERTa model."
            )

    with gr.Row():
        gr.Markdown("### Examples:")

    
    gr.Examples(
        examples=examples,
        inputs=txt,
        outputs=[table],
        fn=analyze, 
        label="Click an example to analyze",
        cache_examples=True,
    )

    btn.click(fn=analyze, inputs=txt, outputs=[table])

    
    demo.load(
        fn=load_default_example_on_startup, 
        inputs=None,
        outputs=[txt, table] 
    )

demo.queue().launch(share=True)