import streamlit as st
from database import create_tables, register_user, login_user, save_weight, get_weight_history
from model_api import query_model
from prompt_builder import build_prompt

# ---------------- INIT DB ----------------
create_tables()

# ---------------- PAGE CONFIG ----------------
st.set_page_config(page_title="FitPlan AI", layout="centered")

# ---------------- SESSION ----------------
if "user" not in st.session_state:
    st.session_state.user = None


# =========================================================
# LOGIN / SIGNUP PAGE
# =========================================================

if st.session_state.user is None:

    st.title("🏋️ FitPlan AI Login")

    menu = ["Login", "Signup"]
    choice = st.sidebar.selectbox("Menu", menu)

    email = st.text_input("Email")
    password = st.text_input("Password", type="password")

    # ---------------- SIGNUP ----------------
    if choice == "Signup":

        if st.button("Create Account"):

            if register_user(email, password):
                st.success("Account created successfully")
            else:
                st.error("User already exists")

    # ---------------- LOGIN ----------------
    if choice == "Login":

        if st.button("Login"):

            user = login_user(email, password)

            if user:
                st.session_state.user = email
                st.success("Login successful")
                st.rerun()
            else:
                st.error("Invalid email or password")


# =========================================================
# MAIN APP
# =========================================================

else:

    st.title("🏋️ FitPlan AI — Personalized Workout Generator")

    st.sidebar.success(f"Logged in as {st.session_state.user}")

    if st.sidebar.button("Logout"):
        st.session_state.user = None
        st.rerun()

    st.write("Fill your fitness details to generate a workout plan.")

    # ---------------- USER INPUT ----------------

    name = st.text_input("Name")

    age = st.number_input(
        "Age",
        min_value=10,
        max_value=100
    )

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

    height = st.number_input(
        "Height (cm)",
        min_value=100.0,
        max_value=250.0
    )

    weight = st.number_input(
        "Weight (kg)",
        min_value=30.0,
        max_value=200.0
    )

    goal = st.selectbox(
        "Fitness Goal",
        [
            "Build Muscle",
            "Lose Weight",
            "Improve Endurance",
            "General Fitness"
        ]
    )

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

    equipment = st.multiselect(
        "Available Equipment",
        [
            "No Equipment",
            "Dumbbells",
            "Barbell",
            "Pull-up Bar",
            "Resistance Bands",
            "Treadmill",
            "Kettlebells",
            "Full Gym"
        ]
    )

    # ---------------- SAVE WEIGHT ----------------

    if st.button("Save Today's Weight"):
        save_weight(st.session_state.user, weight)
        st.success("Weight saved")

    # ---------------- WEIGHT HISTORY ----------------

    if st.button("View Weight History"):

        data = get_weight_history(st.session_state.user)

        if data:
            st.write("📊 Weight History")
            st.table(data)
        else:
            st.info("No weight history available")

    # ---------------- GENERATE WORKOUT ----------------

    if st.button("Generate Workout Plan"):

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

        elif not equipment:
            st.warning("Select equipment")

        else:

            prompt, bmi, bmi_status = build_prompt(
                name,
                age,
                gender,
                height,
                weight,
                goal,
                fitness_level,
                equipment
            )

            with st.spinner("Generating AI workout plan..."):
                response = query_model(prompt)

            st.subheader("📋 Your Workout Plan")
            st.write(response)

            st.info(f"""
            **Profile Summary**

            BMI: {bmi:.2f} ({bmi_status})

            Goal: {goal}

            Fitness Level: {fitness_level}

            Equipment: {", ".join(equipment)}
            """)