app.py

import gradio as gr
import torch
import numpy as np
from transformers import BertForSequenceClassification, BertTokenizer
import requests
import json
import plotly.express as px
import pandas as pd

# Load model and tokenizer from Hugging Face Hub
repo_id = "logasanjeev/goemotions-bert"
model = BertForSequenceClassification.from_pretrained(repo_id)
tokenizer = BertTokenizer.from_pretrained(repo_id)
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model.to(device)
if torch.cuda.device_count() > 1:
    model = nn.DataParallel(model)
model.eval()

# Load optimized thresholds from Hugging Face Hub
thresholds_url = f"https://huggingface.co/{repo_id}/raw/main/thresholds.json"
response = requests.get(thresholds_url)
thresholds_data = json.loads(response.text)
emotion_labels = thresholds_data["emotion_labels"]
default_thresholds = thresholds_data["thresholds"]

# Prediction function
def predict_emotions(text, confidence_threshold=0.0):
    encodings = tokenizer(
        text,
        padding='max_length',
        truncation=True,
        max_length=128,
        return_tensors='pt'
    )
    input_ids = encodings['input_ids'].to(device)
    attention_mask = encodings['attention_mask'].to(device)
    
    with torch.no_grad():
        outputs = model(input_ids, attention_mask=attention_mask)
        logits = torch.sigmoid(outputs.logits).cpu().numpy()[0]
    
    # Apply thresholds with user-defined confidence boost
    predictions = []
    for i, (logit, thresh) in enumerate(zip(logits, default_thresholds)):
        adjusted_thresh = max(thresh, confidence_threshold)
        if logit >= adjusted_thresh:
            predictions.append((emotion_labels[i], logit))
    
    predictions.sort(key=lambda x: x[1], reverse=True)
    if not predictions:
        return "No emotions predicted above thresholds.", None
    
    # Format output
    text_output = "\n".join([f"{emotion}: {confidence:.4f}" for emotion, confidence in predictions])
    
    # Create bar chart
    df = pd.DataFrame(predictions, columns=["Emotion", "Confidence"])
    fig = px.bar(
        df,
        x="Emotion",
        y="Confidence",
        color="Emotion",
        text="Confidence",
        title="Emotion Confidence Levels",
        height=400
    )
    fig.update_traces(texttemplate='%{text:.2f}', textposition='auto')
    fig.update_layout(showlegend=False, margin=dict(t=40, b=40))
    
    return text_output, fig

# Custom CSS for modern UI
custom_css = """
body {
    font-family: 'Segoe UI', Arial, sans-serif;
}
.gr-panel {
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    background: linear-gradient(145deg, #ffffff, #f0f4f8);
}
.gr-button {
    border-radius: 8px;
    background: #007bff;
    color: white;
    padding: 10px 20px;
    transition: background 0.3s;
}
.gr-button:hover {
    background: #0056b3;
}
#title {
    font-size: 2.5em;
    color: #1a3c6e;
    text-align: center;
    margin-bottom: 20px;
}
#description {
    font-size: 1.1em;
    color: #333;
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}
#theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
}
.dark-mode {
    background: #1a1a1a;
    color: #e0e0e0;
}
.dark-mode .gr-panel {
    background: linear-gradient(145deg, #2a2a2a, #3a3a3a);
}
.dark-mode #title {
    color: #66b3ff;
}
.dark-mode #description {
    color: #b0b0b0;
}
"""

# JavaScript for theme toggle
theme_js = """
function toggleTheme() {
    document.body.classList.toggle('dark-mode');
}
"""

# Gradio Blocks UI
with gr.Blocks(css=custom_css) as demo:
    # Header
    gr.Markdown("<div id='title'>GoEmotions BERT Classifier</div>", elem_id="title")
    gr.Markdown(
        """
        <div id='description'>
        Predict emotions from text using a fine-tuned BERT-base model. 
        Explore 28 emotions with optimized thresholds (Micro F1: 0.6025). 
        Try examples or enter your own text!
        </div>
        """,
        elem_id="description"
    )
    
    # Theme toggle button
    with gr.Row():
        gr.HTML(
            """
            <button id='theme-toggle' onclick='toggleTheme()'>Toggle Dark Mode</button>
            <script>{}</script>
            """.format(theme_js)
        )
    
    # Main input and output
    with gr.Row():
        with gr.Column(scale=1):
            text_input = gr.Textbox(
                label="Enter Your Text",
                placeholder="Type something like 'I’m just chilling today'...",
                lines=3
            )
            confidence_slider = gr.Slider(
                minimum=0.0,
                maximum=0.9,
                value=0.0,
                step=0.05,
                label="Minimum Confidence Threshold",
                info="Adjust to filter low-confidence predictions"
            )
            submit_btn = gr.Button("Predict Emotions", variant="primary")
        
        with gr.Column(scale=1):
            output_text = gr.Textbox(label="Predicted Emotions", lines=5)
            output_plot = gr.Plot(label="Emotion Confidence Chart")
    
    # Example carousel
    examples = gr.Examples(
        examples=[
            "I’m just chilling today.",
            "Thank you for saving my life!",
            "I’m nervous about my exam tomorrow.",
            "I love my new puppy so much!",
            "I’m so relieved the storm passed."
        ],
        inputs=text_input,
        label="Try These Examples"
    )
    
    # Bind prediction
    submit_btn.click(
        fn=predict_emotions,
        inputs=[text_input, confidence_slider],
        outputs=[output_text, output_plot]
    )

# Launch
if __name__ == "__main__":
    demo.launch()