app.py

import gradio as gr

# -------------------------------
# Appliance Wattage (Pakistan Common)
# -------------------------------
APPLIANCES = {
    "LED Light": 15,
    "Ceiling Fan": 80,
    "Refrigerator": 200,
    "LED TV": 120,
    "Washing Machine": 500,
    "Iron": 1000,
    "Water Pump (1 HP)": 750,
    "Air Conditioner (1 Ton)": 1500,
    "Laptop": 100,
    "Desktop Computer": 300
}

PEAK_SUN_HOURS = 5  # Pakistan average

# -------------------------------
# Core Calculation Function
# -------------------------------
def calculate_solar(
    selected_appliances,
    quantities,
    hours,
    city,
    system_type,
    battery_type,
    backup_hours
):
    if not selected_appliances:
        return "❌ Please select at least one appliance."

    total_daily_wh = 0

    for app in selected_appliances:
        qty = quantities.get(app, 1)
        hrs = hours.get(app, 1)
        watt = APPLIANCES[app]
        total_daily_wh += watt * qty * hrs

    daily_units = total_daily_wh / 1000  # kWh

    # Solar system size (kW)
    system_kw = round(daily_units / PEAK_SUN_HOURS, 2)

    # Panels
    panel_watt = 550
    panels_required = int((system_kw * 1000) / panel_watt) + 1

    # Inverter sizing
    inverter_kw = round(system_kw + 1, 1)

    # Battery sizing
    battery_kwh = 0
    if system_type != "On-Grid":
        night_load_wh = (total_daily_wh / 24) * backup_hours
        battery_kwh = round(night_load_wh / 1000, 2)

    # -------------------------------
    # Cost Estimation (PKR)
    # -------------------------------
    panel_cost = system_kw * 1000 * 45
    inverter_cost = inverter_kw * 120000

    if battery_type == "Lithium":
        battery_cost = battery_kwh * 120000
    else:
        battery_cost = battery_kwh * 35000

    subtotal = panel_cost + inverter_cost + battery_cost
    installation = subtotal * 0.10
    total_cost = int(subtotal + installation)

    monthly_units = daily_units * 30
    monthly_saving = int(monthly_units * 60)  # Avg PKR/unit

    # -------------------------------
    # Output Summary
    # -------------------------------
    result = f"""
🌞 **Solar System Recommendation (Pakistan)**

📍 City: {city}  
⚡ System Type: {system_type}

🔌 **Load Summary**
- Daily Consumption: {round(daily_units,2)} Units (kWh)

🔋 **System Design**
- Solar System Size: {system_kw} kW
- Panels Required: {panels_required} × {panel_watt}W
- Inverter Size: {inverter_kw} kW
- Battery Capacity: {battery_kwh} kWh ({battery_type})

💰 **Estimated Cost**
- Total System Cost: PKR {total_cost:,}

📉 **Savings**
- Monthly Units Generated: {round(monthly_units,1)}
- Estimated Monthly Saving: PKR {monthly_saving:,}

⚠️ *Prices are estimates and may vary by market.*
    """

    return result

# -------------------------------
# Gradio UI
# -------------------------------
with gr.Blocks(title="Solar Panel Calculator - Pakistan") as app:
    gr.Markdown("## ☀️ Solar Panel Requirement Calculator (Pakistan)")

    appliance_select = gr.CheckboxGroup(
        choices=list(APPLIANCES.keys()),
        label="Select Appliances"
    )

    quantity_inputs = {}
    hour_inputs = {}

    for appliance in APPLIANCES:
        with gr.Row():
            quantity_inputs[appliance] = gr.Number(
                label=f"{appliance} Quantity", value=1, visible=False
            )
            hour_inputs[appliance] = gr.Number(
                label=f"{appliance} Daily Usage (Hours)", value=5, visible=False
            )

    def toggle_inputs(selected):
        updates = []
        for app in APPLIANCES:
            visible = app in selected
            updates.append(gr.update(visible=visible))
            updates.append(gr.update(visible=visible))
        return updates

    appliance_select.change(
        toggle_inputs,
        appliance_select,
        sum([[quantity_inputs[a], hour_inputs[a]] for a in APPLIANCES], [])
    )

    city = gr.Dropdown(
        ["Lahore", "Karachi", "Islamabad", "Faisalabad", "Multan", "Other"],
        label="City"
    )

    system_type = gr.Radio(
        ["On-Grid", "Off-Grid", "Hybrid"],
        label="Solar System Type",
        value="Hybrid"
    )

    battery_type = gr.Radio(
        ["Lead Acid", "Lithium"],
        label="Battery Type",
        value="Lead Acid"
    )

    backup_hours = gr.Slider(
        2, 12, value=6, step=1, label="Backup Hours Required"
    )

    calculate_btn = gr.Button("🔍 Calculate Solar System")

    output = gr.Textbox(lines=20, label="Result")

    calculate_btn.click(
        calculate_solar,
        inputs=[
            appliance_select,
            quantity_inputs,
            hour_inputs,
            city,
            system_type,
            battery_type,
            backup_hours
        ],
        outputs=output
    )

app.launch()