app.py

import gradio as gr
import re

# -----------------------------------------
# GLOBALS for Bag-of-Words ML Simulation
# -----------------------------------------
positive_word_counts = {}
negative_word_counts = {}
training_data = []

# -----------------------------------------
# 1) Training Function
# -----------------------------------------
def train_model(statement, label):
    """
    Splits a statement into words, increments counts in
    positive_word_counts or negative_word_counts depending on label.
    Returns HTML feedback showing what's been learned.
    """
    global positive_word_counts, negative_word_counts, training_data

    # Basic error check
    statement = statement.strip()
    if not statement:
        return "<p style='color:red;'>Please enter a valid training statement.</p>"

    # Tokenize by letters only
    words = re.findall(r"[a-zA-Z]+", statement.lower())

    # Update dictionary
    if label == "Positive":
        for w in words:
            positive_word_counts[w] = positive_word_counts.get(w, 0) + 1
    else:
        for w in words:
            negative_word_counts[w] = negative_word_counts.get(w, 0) + 1

    training_data.append((statement, label))

    # Construct feedback
    pos_count = len(positive_word_counts)
    neg_count = len(negative_word_counts)
    response = (
        f"<p><b>Trained:</b> '{statement}' as {label}</p>"
        f"<p>Learned {pos_count} unique positive words "
        f"and {neg_count} unique negative words so far.</p>"
    )
    return response

# -----------------------------------------
# 2) Classification Function
# -----------------------------------------
def classify_text(statement):
    """
    Counts how many times each word appears in positive vs. negative.
    Returns the classification result + an explanation.
    """
    statement = statement.strip()
    if not statement:
        return "<p style='color:red;'>Please enter a statement to classify.</p>"

    words = re.findall(r"[a-zA-Z]+", statement.lower())
    pos_score = 0
    neg_score = 0

    # Accumulate scores
    for w in words:
        pos_score += positive_word_counts.get(w, 0)
        neg_score += negative_word_counts.get(w, 0)

    # Decide label
    label = "Positive" if pos_score >= neg_score else "Negative"

    explanation = f"""
    <p><b>Classification:</b> '{statement}' → {label}</p>
    <p>Pos score: {pos_score}, Neg score: {neg_score}</p>
    <h4>How This Simulated ML Works</h4>
    <ul>
      <li>When you train a statement, each word is counted as either positive or negative.</li>
      <li>When classifying, we sum how many times those words appeared in positive vs. negative examples.</li>
      <li>If there are more 'positive' occurrences, we predict Positive; otherwise Negative.</li>
    </ul>
    <p>This is a basic 'Bag-of-Words' approach. Real ML uses more sophisticated methods and bigger datasets.</p>
    """
    return explanation

# -----------------------------------------
# 3) Gradio Interface
# -----------------------------------------
with gr.Blocks(css="footer{display:none !important}") as demo:
    gr.Markdown("## Simulated Machine Learning (Bag-of-Words) Demo")
    gr.Markdown("Train a simple word-count-based model, then classify new statements.")

    gr.Markdown("### Training Section")
    with gr.Row():
        train_statement_input = gr.Textbox(
            label="Training Statement",
            placeholder="e.g. I love this place"
        )
        train_label_dropdown = gr.Dropdown(
            choices=["Positive", "Negative"],
            value="Positive",
            label="Label"
        )
        train_button = gr.Button("Train Statement")
    train_output = gr.HTML()

    train_button.click(
        fn=train_model,
        inputs=[train_statement_input, train_label_dropdown],
        outputs=train_output
    )

    gr.Markdown("### Classification Section")
    with gr.Row():
        classify_statement_input = gr.Textbox(
            label="Test Statement",
            placeholder="e.g. I really love these tacos"
        )
        classify_button = gr.Button("Classify")
    classify_output = gr.HTML()

    classify_button.click(
        fn=classify_text,
        inputs=[classify_statement_input],
        outputs=classify_output
    )

demo.launch()