src/streamlit_app.py

import streamlit as st

# --------------------------------------------------
# Page Configuration
# --------------------------------------------------
st.set_page_config(
    page_title="FitPlan AI",
    page_icon="💪",
    layout="centered"
)

# --------------------------------------------------
# Custom Styling (HF Compatible)
# --------------------------------------------------
st.markdown("""
<style>
.stApp {
    background: linear-gradient(135deg, #e3f2fd, #f8fbff);
}

.block-container {
    background-color: white;
    padding: 2rem;
    border-radius: 15px;
    max-width: 850px;
}

.stButton > button {
    width: 100%;
    height: 3em;
    border-radius: 8px;
    background-color: #FF4B4B;
    color: white;
    font-size: 16px;
    border: none;
}
</style>
""", unsafe_allow_html=True)

# --------------------------------------------------
# Title Section
# --------------------------------------------------
st.title("💪 FitPlan AI")
st.subheader("Milestone 1: Fitness Profile & BMI Analysis")
st.write("Fill in your details to generate your BMI profile.")

# --------------------------------------------------
# Fitness Profile Form
# --------------------------------------------------
with st.form("fitness_form"):

    st.header("1️⃣ Personal Information")

    name = st.text_input("Full Name *")

    col1, col2 = st.columns(2)
    with col1:
        height = st.number_input(
            "Height (cm) *",
            min_value=0.0,
            step=0.1,
            format="%.2f"
        )

    with col2:
        weight = st.number_input(
            "Weight (kg) *",
            min_value=0.0,
            step=0.1,
            format="%.2f"
        )

    st.divider()

    st.header("2️⃣ Fitness Details")

    goal = st.selectbox(
        "Fitness Goal",
        ["Build Muscle", "Weight Loss", "Strength Gain", "Abs Building", "Flexible"]
    )

    equipment = st.multiselect(
        "Available Equipment",
        ["Dumbbells", "Resistance Band", "Yoga Mat",
         "Kettlebell", "Pull-up Bar", "No Equipment"]
    )

    level = st.radio(
        "Fitness Level",
        ["Beginner", "Intermediate", "Advanced"]
    )

    submit = st.form_submit_button("Generate Profile")

# --------------------------------------------------
# Processing Logic
# --------------------------------------------------
if submit:

    # -------- Input Validation --------
    if not name.strip():
        st.error("⚠ Please enter your name.")
    
    elif height <= 0:
        st.error("⚠ Height must be greater than 0 cm.")
    
    elif weight <= 0:
        st.error("⚠ Weight must be greater than 0 kg.")
    
    else:
        # -------- BMI Calculation --------
        height_m = height / 100  # Convert cm to meters
        bmi = weight / (height_m ** 2)
        bmi = round(bmi, 2)

        # -------- BMI Classification --------
        if bmi < 18.5:
            category = "Underweight"
            color = "blue"
        elif 18.5 <= bmi < 24.9:
            category = "Normal"
            color = "green"
        elif 25 <= bmi < 29.9:
            category = "Overweight"
            color = "orange"
        else:
            category = "Obese"
            color = "red"

        # -------- Display Results --------
        st.success(f"✅ Profile successfully created for {name}!")

        colA, colB = st.columns(2)

        with colA:
            st.metric("Your BMI", bmi)

        with colB:
            st.markdown(f"**BMI Category:** :{color}[{category}]")

        st.info(f"🎯 Goal: {goal} | 📈 Level: {level}")

        if equipment:
            st.write("🏋 Available Equipment:", ", ".join(equipment))
        else:
            st.write("🏋 Available Equipment: None selected")