import streamlit as st
import math

# Title of the app
st.title("🧮 Scientific Calculator")

# Description
st.write("Perform various mathematical operations including basic arithmetic, logarithms, trigonometric functions, and more.")

# Dropdown menu for operations
operation = st.selectbox(
    "Select an operation:",
    [
        "Addition",
        "Subtraction",
        "Multiplication",
        "Division",
        "Power",
        "Square Root",
        "Logarithm (base 10)",
        "Natural Logarithm (ln)",
        "Sine",
        "Cosine",
        "Tangent"
    ]
)

# Input fields for operations
if operation in ["Addition", "Subtraction", "Multiplication", "Division", "Power"]:
    num1 = st.number_input("Enter the first number:", format="%.2f")
    num2 = st.number_input("Enter the second number:", format="%.2f")
    if st.button("Calculate"):
        if operation == "Addition":
            st.success(f"Result: {num1} + {num2} = {num1 + num2}")
        elif operation == "Subtraction":
            st.success(f"Result: {num1} - {num2} = {num1 - num2}")
        elif operation == "Multiplication":
            st.success(f"Result: {num1} * {num2} = {num1 * num2}")
        elif operation == "Division":
            if num2 != 0:
                st.success(f"Result: {num1} / {num2} = {num1 / num2}")
            else:
                st.error("Error: Division by zero is not allowed.")
        elif operation == "Power":
            st.success(f"Result: {num1} ^ {num2} = {math.pow(num1, num2)}")

elif operation == "Square Root":
    num = st.number_input("Enter the number:", format="%.2f")
    if st.button("Calculate"):
        if num >= 0:
            st.success(f"Result: √{num} = {math.sqrt(num)}")
        else:
            st.error("Error: Square root of a negative number is not allowed.")

elif operation == "Logarithm (base 10)":
    num = st.number_input("Enter the number:", format="%.2f")
    if st.button("Calculate"):
        if num > 0:
            st.success(f"Result: log10({num}) = {math.log10(num)}")
        else:
            st.error("Error: Logarithm is only defined for positive numbers.")

elif operation == "Natural Logarithm (ln)":
    num = st.number_input("Enter the number:", format="%.2f")
    if st.button("Calculate"):
        if num > 0:
            st.success(f"Result: ln({num}) = {math.log(num)}")
        else:
            st.error("Error: Natural logarithm is only defined for positive numbers.")

elif operation in ["Sine", "Cosine", "Tangent"]:
    angle = st.number_input("Enter the angle in degrees:", format="%.2f")
    if st.button("Calculate"):
        radians = math.radians(angle)
        if operation == "Sine":
            st.success(f"Result: sin({angle}) = {math.sin(radians)}")
        elif operation == "Cosine":
            st.success(f"Result: cos({angle}) = {math.cos(radians)}")
        elif operation == "Tangent":
            st.success(f"Result: tan({angle}) = {math.tan(radians)}")