"""
VoiceVault — Gradio Application Entry Point
============================================
HuggingFace Spaces entry point and local development server.

Run locally:  python app.py
Deploy:       Push to HuggingFace Spaces (app.py detected automatically)

Architecture:
  4-tab Gradio Blocks layout:
    Tab 1 — Ask VoiceVault  (voice query + streaming answer + TTS)
    Tab 2 — Knowledge Bases (upload + index + manage)
    Tab 3 — Analytics       (query stats + KB inventory)
    Tab 4 — Settings        (runtime parameters)

Startup:
  1. Ensure data directories exist (cfg.ensure_directories)
  2. Initialize KBManager (central SQLite DB)
  3. Lazy-init WhisperTranscriber and AnswerChain (no model downloads at startup)
  4. Build 4-tab Gradio Blocks UI
  5. Launch with Soft theme
"""

from __future__ import annotations

import logging
import sys

import gradio as gr

from config import cfg
from voicevault import __version__
from ui.tabs.ask_tab import build_ask_tab
from ui.tabs.kb_tab import build_kb_tab
from ui.tabs.analytics_tab import build_analytics_tab
from ui.tabs.settings_tab import build_settings_tab
from ui.components.audio_controls import get_tts_html

# ------------------------------------------------------------------ #
# Logging                                                               #
# ------------------------------------------------------------------ #

logging.basicConfig(
    level=logging.DEBUG if cfg.debug else logging.INFO,
    format="%(asctime)s | %(levelname)-8s | %(name)s | %(message)s",
    datefmt="%Y-%m-%d %H:%M:%S",
    handlers=[logging.StreamHandler(sys.stdout)],
)
logger = logging.getLogger(__name__)


# ------------------------------------------------------------------ #
# Startup                                                               #
# ------------------------------------------------------------------ #

_CENTRAL_DB_PATH = cfg.data_dir / "voicevault.db"


def _startup() -> tuple:
    """
    Initialize all pipeline components at startup.

    Returns:
        (kb_manager, transcriber, answer_chain) tuple — passed to UI builders.
    """
    cfg.ensure_directories()

    logger.info("=" * 60)
    logger.info("VoiceVault v%s — Starting up", __version__)
    logger.info("Data directory : %s", cfg.data_dir.resolve())
    logger.info("Central DB     : %s", _CENTRAL_DB_PATH)
    logger.info("Groq key       : %s", "✓ configured" if cfg.has_groq_key() else "✗ not set")
    logger.info("Gemini key     : %s", "✓ configured" if cfg.has_gemini_key() else "✗ not set")
    logger.info("Debug mode     : %s", cfg.debug)
    logger.info("=" * 60)

    if not cfg.has_any_llm_key():
        logger.warning(
            "No LLM API key found. Set GROQ_API_KEY or GEMINI_API_KEY in .env "
            "to enable answer generation."
        )

    # ── KBManager (initializes SQLite schema) ──────────────────────────
    from voicevault.kb.kb_manager import KBManager
    kb_manager = KBManager(db_path=_CENTRAL_DB_PATH)
    logger.info("KBManager initialized — %d KB(s) found", len(kb_manager.list_kbs()))

    # ── WhisperTranscriber (lazy — no model loaded until first query) ──
    from voicevault.asr.whisper_transcriber import WhisperTranscriber
    transcriber = WhisperTranscriber()
    logger.info("WhisperTranscriber ready (lazy — model loads on first use)")

    # ── AnswerChain (lazy — LLM clients created per call) ─────────────
    from voicevault.generation.answer_chain import AnswerChain
    answer_chain = AnswerChain()
    logger.info("AnswerChain ready (Groq primary / Gemini fallback)")

    return kb_manager, transcriber, answer_chain


# ------------------------------------------------------------------ #
# Gradio App Builder                                                    #
# ------------------------------------------------------------------ #


def build_app(kb_manager, transcriber, answer_chain) -> gr.Blocks:
    """
    Construct and return the full Gradio Blocks application.

    Args:
        kb_manager:   KBManager singleton for KB operations.
        transcriber:  WhisperTranscriber singleton (lazy-loaded model).
        answer_chain: AnswerChain singleton (Groq → Gemini).

    Returns:
        Configured gr.Blocks instance (not yet launched).
    """
    with gr.Blocks(
        title="VoiceVault — Voice-First RAG Knowledge Agent",
        analytics_enabled=False,
    ) as demo:

        # ── Header ─────────────────────────────────────────────────
        gr.Markdown(
            f"""
            # 🎙️ VoiceVault
            **Voice-First RAG Knowledge Agent**  · 
            Speak to your documents. Get cited answers out.
              `v{__version__}`
            """
        )

        # ── Web Speech API JS bridge ────────────────────────────────
        gr.HTML(get_tts_html(), visible=False)

        # ── Tabs ───────────────────────────────────────────────────
        with gr.Tabs():

            with gr.Tab("🎙️ Ask VoiceVault"):
                build_ask_tab(
                    transcriber=transcriber,
                    answer_chain=answer_chain,
                    kb_manager=kb_manager,
                    db_path=_CENTRAL_DB_PATH,
                )

            with gr.Tab("📂 Knowledge Bases"):
                build_kb_tab(
                    kb_manager=kb_manager,
                    db_path=_CENTRAL_DB_PATH,
                )

            with gr.Tab("📊 Analytics"):
                build_analytics_tab(
                    kb_manager=kb_manager,
                    db_path=_CENTRAL_DB_PATH,
                )

            with gr.Tab("⚙️ Settings"):
                build_settings_tab()

        # ── Footer ─────────────────────────────────────────────────
        gr.Markdown(
            """
            ---
            <div style="text-align:center; color:#888; font-size:0.8em;">
            VoiceVault · Navnit Amrutharaj ·
            <a href="https://github.com/ninjacode911" target="_blank">github.com/ninjacode911</a> ·
            Stack: Whisper · ChromaDB · LangChain · Groq · Gradio · $0/month
            </div>
            """
        )

    return demo


# ------------------------------------------------------------------ #
# Entry Point                                                           #
# ------------------------------------------------------------------ #


if __name__ == "__main__":
    kb_manager, transcriber, answer_chain = _startup()
    app = build_app(kb_manager, transcriber, answer_chain)
    theme = gr.themes.Soft(
        primary_hue="violet",
        secondary_hue="purple",
        neutral_hue="slate",
        font=[gr.themes.GoogleFont("Inter"), "ui-sans-serif", "system-ui"],
    )
    app.launch(
        server_name=cfg.host,
        server_port=cfg.port,
        share=False,
        show_error=True,
        theme=theme,
    )