"""One-command LIVE demo launcher with preflight checks.

This is the friendly front door for the *local* live demo. It:
  1. checks your .env has a working key setup (GROQ is the only hard requirement),
  2. builds the warehouse DB if it's missing,
  3. makes sure at least one demo item is actually low-stock (resets if needed),
  4. launches the Streamlit dashboard and opens your browser,
  5. prints exactly what to click.

You then drive the whole thing from the dashboard's 🎮 Live demo sidebar —
no second terminal, no run_id juggling.

Run it with the project's Python, from the project root:
    python -m scripts.live_demo
or just double-click  run_live_demo.bat  (Windows).
"""
from __future__ import annotations

import sqlite3
import subprocess
import sys
import time
import webbrowser
from pathlib import Path

# Windows consoles default to cp1252 and crash on emoji/arrows in our banners.
# Force UTF-8 so the launcher never dies on a print() (this bit us before).
for _stream in (sys.stdout, sys.stderr):
    try:
        _stream.reconfigure(encoding="utf-8", errors="replace")  # py3.7+
    except (AttributeError, ValueError):
        pass

sys.path.insert(0, str(Path(__file__).resolve().parent.parent))

from core.config import PROJECT_ROOT, api_key, db_path, settings  # noqa: E402

PORT = settings()["ports"]["ui"]
BAR = "=" * 66


def _c(msg: str, ok: bool | None = True) -> None:
    mark = {True: "  [OK]  ", False: " [FAIL] ", None: " [WARN] "}[ok]
    print(mark + msg)


def preflight() -> bool:
    """Return True if we're clear to launch, False if a hard requirement failed."""
    print(BAR)
    print("  AutoSource — LIVE demo preflight")
    print(BAR)

    ok = True

    # --- 1. Python + package check ---
    _c(f"Python {sys.version.split()[0]} at {sys.executable}")
    try:
        import streamlit  # noqa: F401
        import groq  # noqa: F401
        _c("Core packages importable (streamlit, groq, mcp, a2a-sdk)")
    except ImportError as e:
        _c(f"Missing package: {e.name}. Run:  pip install -r requirements.txt", False)
        return False

    # --- 2. .env / keys ---
    env_file = PROJECT_ROOT / ".env"
    if not env_file.exists():
        _c(".env not found. Copy .env.example to .env and add your GROQ_API_KEY.",
           False)
        return False
    if api_key("GROQ_API_KEY"):
        _c("GROQ_API_KEY present (the negotiation workhorse)")
    else:
        _c("GROQ_API_KEY missing in .env — the live demo cannot negotiate.", False)
        ok = False
    for opt in ("GEMINI_API_KEY", "OPENROUTER_API_KEY", "HF_TOKEN"):
        present = bool(api_key(opt))
        _c(f"{opt} {'present' if present else 'not set (optional)'}",
           True if present else None)

    if not ok:
        return False

    # --- 3. warehouse DB ---
    db = db_path()
    if not db.exists():
        _c("Warehouse DB missing — building it now…", None)
        _build_db()
    else:
        _c(f"Warehouse DB present ({db.name})")

    # --- 4. is the headline demo item actually low-stock? ---
    demo_sku = settings()["app"]["demo_sku"]
    low = _low_stock_items()
    if demo_sku not in low:
        _c(f"Headline item {demo_sku} isn't low-stock (probably on-order from a "
           f"previous run). Resetting warehouse to a clean demo state…", None)
        _build_db()
        low = _low_stock_items()
    _c(f"Low-stock items ready to procure: {', '.join(low) or '(none!)'}",
       demo_sku in low)

    print(BAR)
    return demo_sku in low


def _build_db() -> None:
    subprocess.run([sys.executable, "-m", "scripts.init_db"],
                   cwd=str(PROJECT_ROOT), check=False)


def _low_stock_items() -> list[str]:
    db = db_path()
    if not db.exists():
        return []
    with sqlite3.connect(f"file:{db}?mode=ro", uri=True) as c:
        rows = c.execute("SELECT sku FROM inventory WHERE status='low'").fetchall()
    return [r[0] for r in rows]


def launch_dashboard() -> None:
    url = f"http://localhost:{PORT}/?mode=live"
    print()
    print("  Launching the dashboard… (leave this window open)")
    print()
    print("  WHEN THE BROWSER OPENS:")
    print("    1. Look at the LEFT sidebar → '🎮 Live demo'")
    print("    2. Click  🚀 Trigger stock check & negotiate")
    print("    3. Watch the agents negotiate (~2-4 min on free tiers)")
    print("    4. When the AP2 mandate panel turns yellow → click ✅ Approve")
    print("    5. Between demos, click 🔄 Reset warehouse to make it low-stock again")
    print()
    print(f"  If the browser doesn't open, go to:  {url}")
    print("  To STOP: press Ctrl+C here.")
    print(BAR)

    # open the browser a moment after streamlit starts binding the port
    def _open_later():
        time.sleep(3.5)
        try:
            webbrowser.open(url)
        except Exception:  # noqa: BLE001
            pass

    import threading
    threading.Thread(target=_open_later, daemon=True).start()

    subprocess.run(
        [sys.executable, "-m", "streamlit", "run", "ui/app.py",
         "--server.port", str(PORT), "--server.headless", "true"],
        cwd=str(PROJECT_ROOT), check=False)


def main() -> None:
    if not preflight():
        print()
        print("  Preflight failed — fix the [FAIL] item above and re-run.")
        print("  Most common fix: add GROQ_API_KEY to your .env file.")
        sys.exit(1)
    launch_dashboard()


if __name__ == "__main__":
    main()