import streamlit as st
from app.chat import (
    create_chat_session,
    list_chat_sessions,
    ensure_chat_session,
    delete_chat_session,
    delete_all_chat_sessions,
)
from app.db import supabase


def render_sidebar_sessions():
    """Render the sidebar: sessions list/search/pagination, actions, and logout.
    Assumes st.session_state['user'] exists.
    """
    st.sidebar.header("Percakapan")
    if st.sidebar.button("➕ New Chat", use_container_width=True):
        uid = st.session_state["user"]["id"]
        new_sid = create_chat_session(uid, title="Percakapan Baru")
        st.session_state["session_id"] = new_sid
        for k in ["history", "generated", "past", "input_text", "tts_output", "tts_played"]:
            if k in st.session_state:
                del st.session_state[k]
        st.rerun()

    # Search and pagination controls
    search_query = st.sidebar.text_input("Cari sesi", value=st.session_state.get("session_search", ""))
    st.session_state["session_search"] = search_query

    page_size = st.sidebar.selectbox("Jumlah per halaman", [5, 10, 20, 50], index=1, key="session_page_size")
    current_page = st.session_state.get("session_page", 0)

    # Fetch sessions
    try:
        sessions = list_chat_sessions(st.session_state["user"]["id"], limit=1000)
    except Exception as e:
        st.sidebar.error(f"Tidak dapat memuat sesi: {e}")
        sessions = []

    # Filter by search
    if search_query:
        sq = search_query.lower()
        sessions = [s for s in sessions if sq in (s.get("title") or "").lower() or sq in s.get("id", "").lower()]

    # Pagination
    total = len(sessions)
    start = current_page * page_size
    end = start + page_size
    page_sessions = sessions[start:end]

    cols = st.sidebar.columns([1, 3, 1])
    disable_prev = current_page <= 0
    disable_next = end >= total
    if cols[0].button("←", disabled=disable_prev):
        st.session_state["session_page"] = max(0, current_page - 1)
        st.rerun()
    cols[1].markdown(f"Halaman {current_page + 1} / {max(1, (total + page_size - 1) // page_size)}")
    if cols[2].button("→", disabled=disable_next):
        st.session_state["session_page"] = current_page + 1
        st.rerun()

    # List sessions with select and delete
    for s in page_sessions:
        sid = s["id"]
        title = s.get("title") or sid
        row = st.sidebar.container()
        subcols = row.columns([6, 1])
        if subcols[0].button(title, key=f"select_{sid}"):
            st.session_state["session_id"] = sid
            ensure_chat_session(st.session_state["user"]["id"], sid)  # ensure selected session exists
            # Clear local caches if switching
            for k in ["history", "generated", "past"]:
                if k in st.session_state:
                    del st.session_state[k]
            st.rerun()
        if subcols[1].button("❌", key=f"del_{sid}"):
            try:
                ok = delete_chat_session(st.session_state["user"]["id"], sid)
                if ok:
                    # If deleting active, choose next one or create new
                    if st.session_state.get("session_id") == sid:
                        remaining = [x for x in sessions if x["id"] != sid]
                        if remaining:
                            st.session_state["session_id"] = remaining[0]["id"]
                        else:
                            st.session_state["session_id"] = create_chat_session(st.session_state["user"]["id"], title="Percakapan Baru")
                    for k in ["history", "generated", "past"]:
                        if k in st.session_state:
                            del st.session_state[k]
                    st.success("Sesi dihapus")
                    st.rerun()
                else:
                    st.error("Gagal menghapus sesi")
            except Exception as e:
                st.error(f"Gagal menghapus: {e}")

    st.sidebar.divider()
    with st.sidebar.expander("Hapus Semua Percakapan", expanded=False):
        confirm = st.checkbox("Saya yakin ingin menghapus semua percakapan", key="confirm_delete_all")
        if st.button("Hapus Semua", type="primary", disabled=not confirm):
            try:
                ok = delete_all_chat_sessions(st.session_state["user"]["id"])
                if ok:
                    st.session_state["session_id"] = create_chat_session(st.session_state["user"]["id"], title="Percakapan Baru")
                    for k in ["history", "generated", "past"]:
                        if k in st.session_state:
                            del st.session_state[k]
                    st.success("Semua percakapan dihapus")
                    st.rerun()
                else:
                    st.error("Gagal menghapus semua percakapan")
            except Exception as e:
                st.error(f"Gagal menghapus semua: {e}")

    st.sidebar.divider()
    if st.sidebar.button("Logout"):
        try:
            supabase.auth.sign_out()
        except Exception:
            pass
        for k in [
            "user", "history", "generated", "past", "input_text",
            "tts_output", "tts_played", "vector_store", "session_id", "sb_session"
        ]:
            if k in st.session_state:
                del st.session_state[k]
        st.success("Anda telah logout")
        st.rerun()