app.py

import gradio as gr
import joblib
import numpy as np
import matplotlib.pyplot as plt

# Load the model - Make sure 'dynamic_pricing_model.pkl' is in the same directory
# or provide the full path to your model file.
try:
    model = joblib.load("dynamic_pricing_model.pkl")
except FileNotFoundError:
    print("Error: 'dynamic_pricing_model.pkl' not found. Please ensure the model file is in the correct directory.")
    print("For demonstration purposes, a dummy model will be used.")
    # Create a dummy model for demonstration if the actual model is not found
    class DummyModel:
        def predict(self, X):
            # Simple dummy prediction logic
            demand, stock, expiry, perishable = X[0]
            base_price = 100.0
            price = base_price + (demand * 0.5) - (stock * 0.2)
            if perishable and expiry > 0:
                price -= (10 - min(expiry, 10)) * 2 # Price drops as expiry nears
            return [max(10, price)] # Ensure price is not too low
    model = DummyModel()


# Prediction and chart generation
def predict_price_and_plot(forecasted_demand, stock, expiry_days, is_perishable):
    # Ensure inputs are numerical and handle potential edge cases for model prediction
    forecasted_demand = max(0, float(forecasted_demand))
    stock = max(0, float(stock))
    expiry_days = max(0, float(expiry_days))
    is_perishable_int = int(bool(is_perishable)) # Convert to 0 or 1

    X = np.array([[forecasted_demand, stock, expiry_days, is_perishable_int]])
    price = model.predict(X)[0]

    # Create a modern, beautiful chart
    plt.style.use('dark_background')
    fig, ax = plt.subplots(figsize=(10, 6))
    
    # Modern gradient colors
    colors = ['#667eea', '#764ba2']
    
    # Create bars with modern styling
    bars = ax.bar(['Forecasted Demand', 'Current Stock'], 
                  [forecasted_demand, stock], 
                  color=colors, 
                  width=0.6, 
                  alpha=0.8,
                  edgecolor='white',
                  linewidth=2)

    # Modern title and labels
    ax.set_title("📊 Demand vs Stock Analysis", 
                 fontsize=20, 
                 fontweight='bold', 
                 color='white',
                 pad=20)
    ax.set_ylabel("Quantity", fontsize=14, color='white')
    
    # Style the axes
    ax.tick_params(axis='both', colors='white', labelsize=12)
    ax.set_facecolor('#1a1a2e')
    fig.patch.set_facecolor('#1a1a2e')
    
    # Remove top and right spines
    ax.spines['top'].set_visible(False)
    ax.spines['right'].set_visible(False)
    ax.spines['left'].set_color('white')
    ax.spines['bottom'].set_color('white')
    
    # Add subtle grid
    ax.grid(axis='y', alpha=0.3, linestyle='--', color='gray')
    
    # Add value labels on bars
    for bar in bars:
        height = bar.get_height()
        ax.text(bar.get_x() + bar.get_width()/2., height + height*0.01,
                f'{int(height)}',
                ha='center', va='bottom', 
                fontsize=14, fontweight='bold', color='white')
    
    plt.tight_layout()
    
    return f"₹{round(price, 2)}", fig

# Custom CSS for modern, responsive design
css = """

/* Import modern fonts */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');



/* Root variables for consistent theming */

:root {

    --primary-color: #667eea;

    --secondary-color: #764ba2;

    --accent-color: #f093fb;

    --background-dark: #0f0f23;

    --background-card: #1a1a2e;

    --text-primary: #ffffff;

    --text-secondary: #a0a0a0;

    --border-color: #333366;

    --success-color: #4ade80;

    --warning-color: #f59e0b;

}



/* Global styles */

* {

    box-sizing: border-box;

}



body {

    font-family: 'Inter', sans-serif !important;

    background: linear-gradient(135deg, var(--background-dark) 0%, #16213e 100%) !important;

    color: var(--text-primary) !important;

    margin: 0;

    padding: 0;

}



/* Main container */

.gradio-container {

    max-width: 1400px !important;

    margin: 0 auto !important;

    padding: 20px !important;

    background: transparent !important;

}



/* Header styling */

.header-section {

    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);

    border-radius: 20px;

    padding: 40px 20px;

    text-align: center;

    margin-bottom: 30px;

    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);

    position: relative;

    overflow: hidden;

}



.header-section::before {

    content: '';

    position: absolute;

    top: 0;

    left: 0;

    right: 0;

    bottom: 0;

    background: linear-gradient(45deg, rgba(255,255,255,0.1) 0%, transparent 100%);

    pointer-events: none;

}



.header-title {

    font-size: clamp(2rem, 5vw, 3.5rem) !important;

    font-weight: 700 !important;

    margin-bottom: 15px !important;

    text-shadow: 2px 2px 10px rgba(0,0,0,0.3);

    color: white !important;

}



.header-subtitle {

    font-size: clamp(1rem, 2.5vw, 1.3rem) !important;

    opacity: 0.9;

    max-width: 600px;

    margin: 0 auto;

    line-height: 1.6;

    color: rgba(255,255,255,0.95) !important;

}



/* Card styling */

.input-card, .output-card {

    background: var(--background-card) !important;

    border-radius: 20px !important;

    padding: 30px !important;

    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2) !important;

    border: 1px solid var(--border-color) !important;

    backdrop-filter: blur(10px);

    margin-bottom: 20px;

}



/* Section headers */

.section-header {

    font-size: 1.5rem !important;

    font-weight: 600 !important;

    color: var(--primary-color) !important;

    margin-bottom: 25px !important;

    text-align: center;

    position: relative;

}



.section-header::after {

    content: '';

    position: absolute;

    bottom: -8px;

    left: 50%;

    transform: translateX(-50%);

    width: 50px;

    height: 3px;

    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));

    border-radius: 2px;

}



/* Input styling */

.gr-textbox, .gr-number {

    margin-bottom: 20px !important;

}



.gr-textbox label, .gr-number label, .gr-checkbox label {

    font-weight: 500 !important;

    color: var(--text-primary) !important;

    font-size: 1rem !important;

    margin-bottom: 8px !important;

}



.gr-textbox input, .gr-number input {

    background: rgba(255,255,255,0.05) !important;

    border: 2px solid var(--border-color) !important;

    border-radius: 12px !important;

    padding: 12px 16px !important;

    color: var(--text-primary) !important;

    font-size: 1rem !important;

    transition: all 0.3s ease !important;

}



.gr-textbox input:focus, .gr-number input:focus {

    border-color: var(--primary-color) !important;

    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1) !important;

    outline: none !important;

}



/* Checkbox styling */

.gr-checkbox {

    margin: 20px 0 !important;

}



.gr-checkbox input[type="checkbox"] {

    width: 20px !important;

    height: 20px !important;

    margin-right: 12px !important;

    accent-color: var(--primary-color) !important;

}



/* Button styling */

.gr-button {

    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%) !important;

    border: none !important;

    border-radius: 12px !important;

    padding: 16px 32px !important;

    font-size: 1.1rem !important;

    font-weight: 600 !important;

    color: white !important;

    cursor: pointer !important;

    transition: all 0.3s ease !important;

    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3) !important;

    width: 100% !important;

    margin-top: 10px !important;

}



.gr-button:hover {

    transform: translateY(-2px) !important;

    box-shadow: 0 12px 35px rgba(102, 126, 234, 0.4) !important;

}



.gr-button:active {

    transform: translateY(0) !important;

}



/* Price output styling */

.price-output {

    background: linear-gradient(135deg, var(--success-color) 0%, #22c55e 100%) !important;

    border-radius: 16px !important;

    padding: 20px !important;

    text-align: center !important;

    margin-bottom: 20px !important;

    box-shadow: 0 10px 30px rgba(74, 222, 128, 0.2) !important;

}



.price-output textarea {

    background: transparent !important;

    border: none !important;

    font-size: 2.5rem !important;

    font-weight: 700 !important;

    color: white !important;

    text-align: center !important;

    resize: none !important;

    outline: none !important;

}



/* Chart container */

.gr-plot {

    border-radius: 16px !important;

    overflow: hidden !important;

    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2) !important;

}



/* Responsive design */

@media (max-width: 1024px) {

    .gradio-container {

        padding: 15px !important;

    }

    

    .input-card, .output-card {

        padding: 25px !important;

    }

}



@media (max-width: 768px) {

    .gradio-container {

        padding: 10px !important;

    }

    

    .header-section {

        padding: 30px 15px !important;

        margin-bottom: 20px !important;

    }

    

    .input-card, .output-card {

        padding: 20px !important;

        margin-bottom: 15px !important;

    }

    

    .gr-row {

        flex-direction: column !important;

    }

    

    .gr-column {

        width: 100% !important;

        margin-bottom: 20px !important;

    }

}



@media (max-width: 480px) {

    .header-section {

        padding: 25px 10px !important;

    }

    

    .input-card, .output-card {

        padding: 15px !important;

    }

    

    .gr-button {

        padding: 14px 24px !important;

        font-size: 1rem !important;

    }

    

    .price-output textarea {

        font-size: 2rem !important;

    }

}



/* Loading states */

.gr-button:disabled {

    opacity: 0.6 !important;

    cursor: not-allowed !important;

}



/* Animations */

@keyframes fadeIn {

    from { opacity: 0; transform: translateY(20px); }

    to { opacity: 1; transform: translateY(0); }

}



.input-card, .output-card {

    animation: fadeIn 0.6s ease forwards;

}



/* Custom scrollbar */

::-webkit-scrollbar {

    width: 8px;

}



::-webkit-scrollbar-track {

    background: var(--background-dark);

}



::-webkit-scrollbar-thumb {

    background: var(--primary-color);

    border-radius: 4px;

}



::-webkit-scrollbar-thumb:hover {

    background: var(--secondary-color);

}

"""

# Create the Gradio interface
with gr.Blocks(
    title="Dynamic Pricing Engine", 
    css=css,
    theme=gr.themes.Base(
        primary_hue="blue",
        secondary_hue="purple",
        neutral_hue="slate"
    )
) as demo:
    
    # Header
    gr.HTML("""

        <div class="header-section">

            <h1 class="header-title">💰 Dynamic Pricing Engine</h1>

            <p class="header-subtitle">

                Harness the power of AI to optimize your product pricing in real-time. 

                Get intelligent price predictions based on demand forecasts, inventory levels, and product characteristics.

            </p>

        </div>

    """)
    
    # Main content
    with gr.Row():
        with gr.Column(scale=1, elem_classes="input-section"):
            with gr.Group(elem_classes="input-card"):
                gr.HTML('<h3 class="section-header">📊 Product Information</h3>')
                
                forecasted_demand = gr.Number(
                    label="📈 Forecasted Demand (Units)",
                    value=50,
                    minimum=0,
                    info="Expected demand for the product"
                )
                
                stock = gr.Number(
                    label="📦 Current Stock Level (Units)",
                    value=100,
                    minimum=0,
                    info="Available inventory quantity"
                )
                
                expiry_days = gr.Number(
                    label="⏰ Days Until Expiry",
                    value=10,
                    minimum=0,
                    info="Set to 0 for non-perishable products"
                )
                
                is_perishable = gr.Checkbox(
                    label="🍎 Perishable Product",
                    value=True,
                    info="Check if product has expiration date"
                )
                
                submit_btn = gr.Button(
                    "🚀 Calculate Optimal Price",
                    variant="primary",
                    size="lg"
                )
        
        with gr.Column(scale=1, elem_classes="output-section"):
            with gr.Group(elem_classes="output-card"):
                gr.HTML('<h3 class="section-header">💡 Pricing Insights</h3>')
                
                price_output = gr.Textbox(
                    label="💰 Recommended Price (₹)",
                    placeholder="Click 'Calculate Optimal Price' to see prediction...",
                    interactive=False,
                    elem_classes="price-output"
                )
                
                chart_output = gr.Plot(
                    label="📊 Market Analysis",
                    show_label=True
                )
    
    # Event handlers
    submit_btn.click(
        fn=predict_price_and_plot,
        inputs=[forecasted_demand, stock, expiry_days, is_perishable],
        outputs=[price_output, chart_output]
    )
    
    # Auto-calculate on input change (optional)
    for input_component in [forecasted_demand, stock, expiry_days, is_perishable]:
        input_component.change(
            fn=predict_price_and_plot,
            inputs=[forecasted_demand, stock, expiry_days, is_perishable],
            outputs=[price_output, chart_output]
        )

if __name__ == "__main__":
    demo.launch(share=True)