"""
Antigravity Notebook - Streamlit UI
NotebookLM-style interface for the Antigravity Notebook system.
"""

import streamlit as st
import requests
from typing import List, Dict, Optional
import plotly.graph_objects as go
from datetime import datetime

# API Configuration
API_BASE_URL = "http://localhost:8000"


def init_session_state():
    """Initialize session state variables"""
    if "selected_notebook_id" not in st.session_state:
        st.session_state.selected_notebook_id = None
    if "chat_messages" not in st.session_state:
        st.session_state.chat_messages = []
    if "notebooks" not in st.session_state:
        st.session_state.notebooks = []


def api_call(method: str, endpoint: str, **kwargs):
    """Make API call with error handling"""
    url = f"{API_BASE_URL}{endpoint}"
    try:
        response = requests.request(method, url, **kwargs)
        response.raise_for_status()
        return response.json() if response.text else None
    except requests.exceptions.RequestException as e:
        st.error(f"API Error: {e}")
        return None


def load_notebooks() -> List[Dict]:
    """Load all notebooks"""
    data = api_call("GET", "/notebooks/")
    return data if data else []


def create_notebook(name: str, description: str = ""):
    """Create a new notebook"""
    return api_call("POST", "/notebooks/", json={
        "name": name,
        "description": description
    })


def get_notebook_details(notebook_id: str) -> Optional[Dict]:
    """Get detailed notebook information"""
    return api_call("GET", f"/notebooks/{notebook_id}")


def get_notebook_stats(notebook_id: str) -> Optional[Dict]:
    """Get notebook statistics"""
    return api_call("GET", f"/notebooks/{notebook_id}/stats")


def upload_pdf(notebook_id: str, file):
    """Upload a PDF file"""
    files = {"file": (file.name, file, "application/pdf")}
    return api_call("POST", f"/sources/notebooks/{notebook_id}/sources/upload", files=files)


def add_url_source(notebook_id: str, url: str, title: str = None):
    """Add a URL source"""
    return api_call("POST", f"/sources/notebooks/{notebook_id}/sources/url", json={
        "url": url,
        "title": title
    })


def add_text_source(notebook_id: str, content: str, title: str):
    """Add text source"""
    return api_call("POST", f"/sources/notebooks/{notebook_id}/sources/text", json={
        "content": content,
        "title": title
    })


def delete_source(source_id: str):
    """Delete a source"""
    return api_call("DELETE", f"/sources/sources/{source_id}")


def query_notebook(notebook_id: str, query: str) -> Optional[Dict]:
    """Query the notebook"""
    return api_call("POST", f"/chat/notebooks/{notebook_id}/chat", json={
        "query": query,
        "include_history": True
    })


def get_chat_history(notebook_id: str) -> List[Dict]:
    """Get chat history"""
    data = api_call("GET", f"/chat/notebooks/{notebook_id}/messages")
    return data if data else []


def render_memory_gauge(stats: Dict):
    """Render memory usage gauge"""
    usage_percent = stats.get("context_usage_percent", 0)

    fig = go.Figure(go.Indicator(
        mode="gauge+number+delta",
        value=usage_percent,
        title={'text': "Context Usage"},
        delta={'reference': 100},
        gauge={
            'axis': {'range': [None, 100]},
            'bar': {'color': "darkblue"},
            'steps': [
                {'range': [0, 50], 'color': "lightgreen"},
                {'range': [50, 80], 'color': "yellow"},
                {'range': [80, 100], 'color': "orange"}
            ],
            'threshold': {
                'line': {'color': "red", 'width': 4},
                'thickness': 0.75,
                'value': 100
            }
        }
    ))

    fig.update_layout(height=200, margin=dict(l=20, r=20, t=40, b=20))

    st.plotly_chart(fig, use_container_width=True)

    # Stats details
    st.caption(f"📊 {stats.get('total_tokens', 0):,} / {stats.get('max_context_tokens', 0):,} tokens")

    if stats.get('can_fit_full_context', True):
        st.success("✅ Full notebook fits in context!")
    else:
        st.warning("⚠️  Using selective retrieval")


def render_sidebar():
    """Render the left sidebar with notebook and source management"""
    with st.sidebar:
        st.title("📚 Antigravity Notebook")

        # Notebook selector
        st.subheader("Notebooks")

        notebooks = load_notebooks()
        st.session_state.notebooks = notebooks

        if notebooks:
            notebook_options = {nb["name"]: nb["id"] for nb in notebooks}
            selected_name = st.selectbox(
                "Select Notebook",
                options=list(notebook_options.keys()),
                key="notebook_selector"
            )
            st.session_state.selected_notebook_id = notebook_options[selected_name]
        else:
            st.info("No notebooks yet. Create one below!")
            st.session_state.selected_notebook_id = None

        # Create new notebook
        with st.expander("➕ Create New Notebook"):
            new_name = st.text_input("Name", key="new_notebook_name")
            new_desc = st.text_area("Description (optional)", key="new_notebook_desc")

            if st.button("Create Notebook"):
                if new_name:
                    result = create_notebook(new_name, new_desc)
                    if result:
                        st.success(f"Created: {new_name}")
                        st.rerun()
                else:
                    st.error("Name is required")

        st.divider()

        # Sources management (only if notebook selected)
        if st.session_state.selected_notebook_id:
            notebook_id = st.session_state.selected_notebook_id

            # Get notebook details
            details = get_notebook_details(notebook_id)
            stats = get_notebook_stats(notebook_id)

            if details and stats:
                st.subheader("📁 Sources")

                # Display sources
                sources = details.get("sources", [])

                if sources:
                    for source in sources:
                        with st.container():
                            col1, col2 = st.columns([3, 1])

                            with col1:
                                icon = {"pdf": "📄", "url": "🌐", "text": "📝"}.get(
                                    source["source_type"], "📎"
                                )
                                st.write(f"{icon} {source['filename']}")
                                st.caption(f"{source['total_tokens']} tokens")

                            with col2:
                                if st.button("🗑️", key=f"delete_{source['id']}"):
                                    delete_source(source['id'])
                                    st.rerun()

                        st.divider()
                else:
                    st.info("No sources yet. Add some below!")

                # Add sources
                st.subheader("➕ Add Source")

                tab1, tab2, tab3 = st.tabs(["📄 PDF", "🌐 URL", "📝 Text"])

                with tab1:
                    uploaded_file = st.file_uploader(
                        "Upload PDF",
                        type=["pdf"],
                        key="pdf_uploader"
                    )
                    if uploaded_file and st.button("Upload PDF"):
                        with st.spinner("Processing PDF..."):
                            result = upload_pdf(notebook_id, uploaded_file)
                            if result:
                                st.success("PDF uploaded!")
                                st.rerun()

                with tab2:
                    url_input = st.text_input("URL", key="url_input")
                    url_title = st.text_input("Title (optional)", key="url_title")

                    if st.button("Add URL"):
                        if url_input:
                            with st.spinner("Scraping URL..."):
                                result = add_url_source(
                                    notebook_id,
                                    url_input,
                                    url_title if url_title else None
                                )
                                if result:
                                    st.success("URL added!")
                                    st.rerun()
                        else:
                            st.error("URL is required")

                with tab3:
                    text_title = st.text_input("Title", key="text_title")
                    text_content = st.text_area("Content", key="text_content", height=150)

                    if st.button("Add Text"):
                        if text_title and text_content:
                            with st.spinner("Processing text..."):
                                result = add_text_source(notebook_id, text_content, text_title)
                                if result:
                                    st.success("Text added!")
                                    st.rerun()
                        else:
                            st.error("Title and content are required")

                st.divider()

                # Memory gauge
                st.subheader("🧠 Memory Usage")
                render_memory_gauge(stats)


def render_main_chat():
    """Render the main chat interface"""
    st.title("💬 Chat with Your Notebook")

    if not st.session_state.selected_notebook_id:
        st.info("👈 Select or create a notebook to start chatting")
        return

    notebook_id = st.session_state.selected_notebook_id

    # Get notebook details
    details = get_notebook_details(notebook_id)
    if not details:
        st.error("Failed to load notebook")
        return

    st.subheader(f"📓 {details['name']}")
    if details.get('description'):
        st.caption(details['description'])

    # Check if sources exist
    if not details.get('sources'):
        st.warning("⚠️  No sources in this notebook. Add some sources to start chatting!")
        return

    st.divider()

    # Load chat history
    chat_history = get_chat_history(notebook_id)

    # Display chat history
    for message in chat_history:
        role = message["role"]
        content = message["content"]

        if role == "user":
            with st.chat_message("user"):
                st.write(content)
        else:
            with st.chat_message("assistant"):
                st.write(content)

                # Show sources if available
                sources = message.get("sources_used", [])
                if sources:
                    with st.expander("📚 Sources"):
                        unique_sources = {}
                        for src in sources:
                            key = src["source_id"]
                            if key not in unique_sources:
                                unique_sources[key] = src

                        for src in unique_sources.values():
                            st.caption(f"• {src['filename']} ({src['source_type']})")

    # Chat input
    user_query = st.chat_input("Ask a question about your sources...")

    if user_query:
        # Display user message
        with st.chat_message("user"):
            st.write(user_query)

        # Query the notebook
        with st.chat_message("assistant"):
            with st.spinner("Thinking..."):
                response = query_notebook(notebook_id, user_query)

                if response:
                    st.write(response["response"])

                    # Show sources
                    sources = response.get("sources_used", [])
                    if sources:
                        with st.expander("📚 Sources"):
                            unique_sources = {}
                            for src in sources:
                                key = src["source_id"]
                                if key not in unique_sources:
                                    unique_sources[key] = src

                            for src in unique_sources.values():
                                st.caption(f"• {src['filename']} ({src['source_type']})")

                    # Show token usage
                    token_usage = response.get("token_usage", {})
                    if token_usage:
                        st.caption(
                            f"📊 Used {token_usage.get('selected_tokens', 0):,} / "
                            f"{token_usage.get('max_tokens', 0):,} tokens "
                            f"({token_usage.get('usage_percent', 0):.1f}%)"
                        )
                else:
                    st.error("Failed to get response")

        # Rerun to show the new message in history
        st.rerun()


def main():
    """Main application"""
    st.set_page_config(
        page_title="Antigravity Notebook",
        page_icon="📚",
        layout="wide",
        initial_sidebar_state="expanded"
    )

    init_session_state()

    # Render sidebar
    render_sidebar()

    # Render main chat area
    render_main_chat()


if __name__ == "__main__":
    main()