import sys
from pathlib import Path
import os
import gdown
import streamlit as st

# Set page config - must be first Streamlit command
st.set_page_config(
    page_title="TruthCheck - Advanced Fake News Detector",
    page_icon="🛡️",
    layout="wide",
    initial_sidebar_state="expanded"
)

# Custom CSS with Poppins font
st.markdown("""
<style>
    @import url('https://fonts.googleapis.com/css2?family=Poppins:wght@200;300;400;500;600;700&display=swap');

    * {
        font-family: 'Poppins', sans-serif !important;
        box-sizing: border-box;
    }

    .stApp {
        background: #ffffff;
        min-height: 100vh;
        color: #1f2a44;
        margin: 0 !important;
        padding: 0 !important;
    }

    .sidebar .sidebar-content {
        background-color: #F4F7FA;
        padding: 1rem;
    }

    .stButton>button {
        background-color: #4B5EAA;
        color: white;
        border-radius: 8px;
        padding: 0.5rem 1rem;
        font-weight: 600;
        transition: background-color 0.3s;
    }

    .stButton>button:hover {
        background-color: #3A4A8C;
    }

    .stTextArea textarea {
        border: 1px solid #E0E0E0;
        border-radius: 8px;
        padding: 1rem;
    }

    /* Enhanced sidebar styling */
    .stRadio > div {
        gap: 0.5rem;
    }

    .stRadio > div > label {
        padding: 0.5rem 1rem;
        border-radius: 8px;
        transition: all 0.3s ease;
        cursor: pointer;
        font-weight: 500;
    }

    .stRadio > div > label:hover {
        background-color: #E8F0FE;
        transform: translateX(5px);
    }

    .stRadio > div > label[data-checked="true"] {
        background-color: #4B5EAA;
        color: white;
    }
</style>
""", unsafe_allow_html=True)

MODEL_PATH = "models/saved/final_model.pt"
GOOGLE_DRIVE_FILE_ID = "1xhYKuC5_Yri3mm3Ejt-SpB2WAVUTJvc_"
GOOGLE_DRIVE_URL = f"https://drive.google.com/uc?id={GOOGLE_DRIVE_FILE_ID}"

@st.cache_resource
def download_model():
    """Download model from Google Drive if not exists."""
    if not os.path.exists(MODEL_PATH):
        os.makedirs(os.path.dirname(MODEL_PATH), exist_ok=True)
        with st.spinner("Downloading model from Google Drive..."):
            try:
                gdown.download(GOOGLE_DRIVE_URL, MODEL_PATH, quiet=False)
                st.markdown('<div class="flash-message success-message">Model downloaded successfully!</div>', unsafe_allow_html=True)
            except Exception as e:
                st.markdown(f'<div class="flash-message error-message">Failed to download model: {str(e)}</div>', unsafe_allow_html=True)
                st.markdown('<div class="flash-message error-message">Please check your Google Drive link and ensure the file is publicly accessible.</div>', unsafe_allow_html=True)
                return False
    return True

# Add src directory to Python path
src_path = Path(__file__).parent / "src"
sys.path.append(str(src_path))

# Enhanced Sidebar navigation with icons
st.sidebar.markdown("""
<div style="text-align: center; margin-bottom: 2rem;">
    <div style="font-size: 3rem; margin-bottom: 0.5rem;">🛡️</div>
    <h1 style="color: #4B5EAA; font-size: 1.8rem; font-weight: 700; margin-bottom: 0.5rem; line-height: 1.2;">
        TruthCheck
    </h1>
    <p style="color: #666; font-size: 1rem; margin: 0; font-weight: 300; line-height: 1.3;">
        Advanced Fake News Detector
    </p>
</div>
""", unsafe_allow_html=True)

st.sidebar.markdown("---")

# Navigation with icons
page = st.sidebar.radio(
    "Navigate",
    [
        "🏠 Home",
        "ℹ️ About", 
        "📋 Terms of Use",
        "🔒 Privacy Policy",
        "📬 Contact"
    ],
    label_visibility="collapsed",
    key="navigation"
)

# Add some spacing and additional info
st.sidebar.markdown("---")
st.sidebar.markdown("""
<div style="text-align: center; padding: 1.5rem; background: linear-gradient(135deg, #F8F9FA 0%, #E8F0FE 100%); border-radius: 12px; margin-top: 1rem; border: 1px solid #E0E7FF;">
    <div style="font-size: 2rem; margin-bottom: 0.8rem;">🔍</div>
    <p style="font-size: 0.85rem; color: #4B5EAA; margin: 0; font-weight: 500; line-height: 1.4;">
        Protecting you from misinformation with AI-powered detection
    </p>
</div>
""", unsafe_allow_html=True)

# Add footer info in sidebar only
st.sidebar.markdown("""
<div style="text-align: center; padding: 0.5rem; margin-top: 2rem;">
    <p style="font-size: 0.7rem; color: #888; margin: 0;">
        © 2025 TruthCheck | AI-Powered
    </p>
</div>
""", unsafe_allow_html=True)

# Clean up the page variable to remove icons for the conditional logic
page_clean = page.split(" ", 1)[1] if " " in page else page

if __name__ == "__main__":
    if page_clean == "Home":
        if download_model():
            from src.app import main
            main()
        else:
            st.markdown('<div class="flash-message error-message">Cannot start the application without the model file.</div>', unsafe_allow_html=True)
    elif page_clean == "About":
        from src.about import main
        main()
    elif page_clean == "Terms of Use":
        from src.terms_of_use import main
        main()
    elif page_clean == "Privacy Policy":
        from src.privacy_policy import main
        main()
    elif page_clean == "Contact":
        from src.contact import main
        main()