import streamlit as st
from transformers import pipeline

# =========================
# Page Configuration
# =========================
st.set_page_config(
    page_title="Fitness Profile",
    page_icon="🏋️",
    layout="centered"
)

# =========================
# Load Model
# =========================
@st.cache_resource
def load_model():
    return pipeline(
        "text-generation",
        model="google/flan-t5-base"
    )

generator = load_model()

st.title("🏋️ Personalized Fitness Profile")
st.markdown("---")

# =========================
# 1️⃣ Personal Information
# =========================
st.header("1. Personal Information")

name = st.text_input("Name *")

gender = st.selectbox(
    "Gender *",
    ["Male", "Female"]
)

height_cm = st.number_input(
    "Height (in centimeters) *",
    min_value=0.0,
    format="%.2f"
)

weight_kg = st.number_input(
    "Weight (in kilograms) *",
    min_value=0.0,
    format="%.2f"
)

# =========================
# BMI Calculation
# =========================
# =========================
# BMI Calculation
# =========================
def calculate_bmi(height_cm, weight_kg):
    if height_cm > 0 and weight_kg > 0:
        height_m = height_cm / 100
        return weight_kg / (height_m ** 2)
    return 0   # Always return something

def bmi_category(bmi):
    if bmi < 18.5:
        return "Underweight"
    elif 18.5 <= bmi < 25:
        return "Normal weight"
    elif 25 <= bmi < 30:
        return "Overweight"
    else:
        return "Obese"

# ALWAYS define bmi safely
bmi = 0
if height_cm > 0 and weight_kg > 0:
    bmi = calculate_bmi(height_cm, weight_kg)
    st.info(f"Your BMI is: {bmi:.2f} ({bmi_category(bmi)})")


# =========================
# 2️⃣ Fitness Details
# =========================
st.header("2. Fitness Details")

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

equipment = st.multiselect(
    "Available Equipment (Multiple selection allowed)",
    ["Dumbbells", "Resistance Band", "Yoga Mat", "No Equipment"]
)

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

st.markdown("---")

# =========================
# Submit Button
# =========================
if st.button("Submit Profile"):

    if not name:
        st.error("Please enter your name.")

    elif height_cm <= 0 or weight_kg <= 0:
        st.error("Please enter valid height and weight.")

    elif not equipment:
        st.error("Please select at least one equipment option.")

    else:
        st.success("✅ Profile Submitted Successfully!")

        bmi_status = bmi_category(bmi)
        equipment_list = ", ".join(equipment)

        prompt = f"""
        Generate a 5-day structured workout plan.

        User Details:
        Name: {name}
        Gender: {gender}
        BMI: {bmi:.2f} ({bmi_status})
        Goal: {fitness_goal}
        Fitness Level: {fitness_level}
        Available Equipment: {equipment_list}

        Requirements:
        - Include warmup
        - Include exercises with sets and reps
        - Include rest time
        - Adjust intensity based on BMI and fitness level
        - Keep it structured day-wise
        """

        with st.spinner("Generating your AI workout plan..."):
            result = generator(
                prompt,
                max_new_tokens=400,
                do_sample=True,
                temperature=0.7
            )[0]["generated_text"]

        st.subheader("🏋️ Your Personalized Workout Plan")
        st.write(result)