app.py

import gradio as gr
from transformers import pipeline
import sys

# Toggle this to True if you want to see debug prints
DEBUG = False

# Load the toxicity classification pipeline
print("Loading toxicity classifier pipeline...")
toxicity_pipeline = pipeline(
    "text-classification",
    model="s-nlp/roberta_toxicity_classifier",
    tokenizer="s-nlp/roberta_toxicity_classifier"
)
print("Pipeline loaded successfully!")


def toxicity_classification(text: str) -> dict:
    """
    Classify the toxicity of the given text.

    Args:
        text (str): The text to analyze

    Returns:
        dict: A dictionary containing toxicity classification and confidence
    """
    if not text.strip():
        return {"error": "Please enter some text to analyze"}

    try:
        # Get the top prediction using the pipeline
        result = toxicity_pipeline(text)[0]

        if DEBUG:
            print(f"DEBUG - Pipeline result: {result}")

        # The model returns labels like "neutral" or "toxic"
        label = result.get("label", "neutral").lower()
        score = result.get("score", 0.0)

        # Map "neutral" (or any non-toxic) to non-toxic
        if label == "toxic":
            classification = "toxic"
            confidence = score
        else:
            classification = "non-toxic"
            confidence = score

        return {
            "classification": classification,
            "confidence": round(confidence, 4)
        }

    except Exception as e:
        return {"error": f"Error processing text: {str(e)}"}


# Create the Gradio interface
demo = gr.Interface(
    fn=toxicity_classification,
    inputs=gr.Textbox(
        placeholder="Enter text to analyze for toxicity...",
        lines=3,
        label="Input Text"
    ),
    outputs=gr.JSON(label="Toxicity Analysis Results"),
    title="Text Toxicity Classification",
    description="Analyze text toxicity using RoBERTa transformer model (s-nlp/roberta_toxicity_classifier)",
    examples=[
        ["You are amazing!"],
        ["This is a wonderful day."],
        ["I hate you so much!"],
        ["You're such an idiot!"],
    ]
)


if __name__ == "__main__":
    # If "debug" was passed as a command-line argument, run local tests
    if len(sys.argv) > 1 and sys.argv[1].lower() == "debug":
        DEBUG = True
        print("=" * 50)
        print("DEBUG MODE - Testing toxicity classification locally")
        print("=" * 50)

        test_cases = [
            "You are amazing!",
            "This is a wonderful day.",
            "I hate you so much!",
            "You're such an idiot!",
            "I disagree with your opinion.",
            ""  # Empty string test
        ]

        for i, test_text in enumerate(test_cases, 1):
            print(f"\n--- Test Case {i} ---")
            print(f"Input: '{test_text}'")
            result = toxicity_classification(test_text)
            print(f"Output: {result}")
            print("-" * 30)

        print("\nDebug testing completed!")
    else:
        # Normal Gradio mode: launch with MCP server enabled
        demo.launch(mcp_server=True)