import streamlit as st
import math

# Title and description
st.title("Pipe Sizing Helper")
st.write("This application helps you determine the recommended pipe diameter based on flow rate and velocity.")

# Input fields for flow rate and velocity
flow_rate = st.number_input("Enter the flow rate (in m³/s):", min_value=0.0, step=0.01, format="%.2f")
velocity = st.number_input("Enter the permissible velocity (in m/s):", min_value=0.0, step=0.1, format="%.1f")

# Calculate pipe diameter
if st.button("Calculate Pipe Diameter"):
    if flow_rate > 0 and velocity > 0:
        # Formula: Diameter (D) = sqrt((4 * Q) / (π * V))
        diameter = math.sqrt((4 * flow_rate) / (math.pi * velocity))
        diameter_mm = diameter * 1000  # Convert to millimeters
        st.success(f"The recommended pipe diameter is {diameter_mm:.2f} mm.")
    else:
        st.error("Please enter positive values for both flow rate and velocity.")