import streamlit as st
import math

# Define the calculator functions
def add(x, y):
    return x + y

def subtract(x, y):
    return x - y

def multiply(x, y):
    return x * y

def divide(x, y):
    if y == 0:
        return "Error! Division by zero."
    else:
        return x / y

def square_root(x):
    if x < 0:
        return "Error! Square root of negative number."
    else:
        return math.sqrt(x)

def power(x, y):
    return math.pow(x, y)

def sine(x):
    return math.sin(math.radians(x))

def cosine(x):
    return math.cos(math.radians(x))

def tangent(x):
    return math.tan(math.radians(x))

def logarithm(x, base=10):
    if x <= 0:
        return "Error! Logarithm of non-positive number."
    else:
        return math.log(x, base)

# Streamlit UI for the calculator
st.title("Scientific Calculator")

# Input fields for the user
num1 = st.number_input("Enter first number:", value=0.0)
num2 = st.number_input("Enter second number (optional):", value=0.0)

# Dropdown for operation selection
operation = st.selectbox("Choose an operation:", [
    "Add", "Subtract", "Multiply", "Divide", 
    "Square Root", "Power", "Sine", "Cosine", "Tangent", "Logarithm"
])

# Handle different operations
if operation == "Add":
    result = add(num1, num2)
elif operation == "Subtract":
    result = subtract(num1, num2)
elif operation == "Multiply":
    result = multiply(num1, num2)
elif operation == "Divide":
    result = divide(num1, num2)
elif operation == "Square Root":
    result = square_root(num1)
elif operation == "Power":
    result = power(num1, num2)
elif operation == "Sine":
    result = sine(num1)
elif operation == "Cosine":
    result = cosine(num1)
elif operation == "Tangent":
    result = tangent(num1)
elif operation == "Logarithm":
    result = logarithm(num1)

# Display the result
st.write(f"Result: {result}")