src/streamlit_app.py

import streamlit as st

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

# --------------------------------------------------
# Custom CSS (Ensuring High Visibility)
# --------------------------------------------------
st.markdown("""
<style>
    /* Force a clean, light background for the whole app */
    .stApp {
        background-color: #F0F2F6;
    }

    /* Card-style container for the form */
    div[data-testid="stForm"] {
        background-color: #FFFFFF !important;
        padding: 30px !important;
        border-radius: 15px !important;
        border: 1px solid #E0E0E0 !important;
        box-shadow: 0 4px 12px rgba(0,0,0,0.05);
    }

    /* Force all text labels and headers to be Dark Blue/Black */
    h1, h2, h3, p, label, .stMarkdown {
        color: #1A1C25 !important;
    }

    /* Style the Input boxes for clarity */
    input {
        color: #1A1C25 !important;
        background-color: #F8F9FA !important;
    }

    /* Button styling */
    .stButton > button {
        width: 100%;
        background: linear-gradient(90deg, #2563eb, #1d4ed8);
        color: white !important;
        font-weight: bold;
        border: none;
        padding: 10px;
        border-radius: 8px;
    }
</style>
""", unsafe_allow_html=True)

# --------------------------------------------------
# Header
# --------------------------------------------------
st.title("💪 FitPlan AI")
st.markdown("### Milestone 1: Fitness Profile & BMI Analysis")
st.write("Complete your profile below to calculate your health metrics.")

# --------------------------------------------------
# Fitness Profile Form
# --------------------------------------------------
with st.form("fitness_form"):
    st.markdown("#### 🧍‍♂️ 1. Personal Information")
    
    name = st.text_input("Full Name *", placeholder="e.g. John Doe")

    col1, col2 = st.columns(2)
    with col1:
        # Added min_value logic to prevent negatives
        height = st.number_input("Height (cm) *", min_value=0.0, step=1.0, format="%.1f")
    with col2:
        weight = st.number_input("Weight (kg) *", min_value=0.0, step=0.1, format="%.1f")

    st.markdown("---")

    st.markdown("#### 🏋️ 2. Fitness Details")
    
    goal = st.selectbox(
        "Fitness Goal",
        ["Build Muscle", "Weight Loss", "Strength Gain", "Abs Building", "Flexible"]
    )

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

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

    submit = st.form_submit_button("Generate Profile")

# --------------------------------------------------
# Logic & Output
# --------------------------------------------------
if submit:
    # Validation checks
    if not name.strip():
        st.error("🚨 Name is required.")
    elif height <= 50 or weight <= 10: # Realistic safety checks
        st.error("🚨 Please enter valid height and weight values.")
    else:
        # BMI Calculation
        height_m = height / 100
        bmi = weight / (height_m ** 2)
        bmi_display = round(bmi, 2)

        # Precise BMI Classification
        if bmi < 18.5:
            category, color, progress = "Underweight", "blue", 0.25
        elif 18.5 <= bmi < 25.0:
            category, color, progress = "Normal", "green", 0.50
        elif 25.0 <= bmi < 30.0:
            category, color, progress = "Overweight", "orange", 0.75
        else:
            category, color, progress = "Obese", "red", 1.0

        # Results Display
        st.success(f"✅ Profile generated for {name}")
        
        m_col1, m_col2 = st.columns(2)
        with m_col1:
            st.metric("Your BMI", f"{bmi_display}")
        with m_col2:
            # Using bold colored markdown for high visibility
            st.markdown(f"**Status:** :{color}[{category}]")

        st.markdown("### 📊 BMI Visual Indicator")
        st.progress(progress)
        
        # Summary Box
        st.info(f"**Profile Summary:**\n\n* **Goal:** {goal}\n* **Experience:** {level}\n* **Equipment:** {', '.join(equipment) if equipment else 'None'}")