"""
main.py — Knowledge Agent entry point
======================================
Starts:
  1. File watcher (background thread) — auto-indexes new/changed documents
  2. FastAPI web server (foreground)  — CLI and web UI

Run:
    python main.py                     # web UI on http://localhost:8000
    python main.py --port 8080         # custom port
    python main.py --no-watcher        # disable file watcher
    python main.py --index-on-start    # index all docs before starting
"""

import argparse
import os
import sys
import uvicorn

import os as _os
from dotenv import load_dotenv
load_dotenv(_os.path.join(_os.path.dirname(_os.path.abspath(__file__)), "..", ".env"))

DOCS_DIR = os.getenv("DOCS_DIR", "./documents")


def main():
    parser = argparse.ArgumentParser(
        description="Knowledge Agent — Personal RAG server"
    )
    parser.add_argument("--host",           default="0.0.0.0",
                        help="Bind host (default: 0.0.0.0)")
    parser.add_argument("--port",           type=int, default=8000,
                        help="Port (default: 8000)")
    parser.add_argument("--no-watcher",     action="store_true",
                        help="Disable the file-system watcher")
    parser.add_argument("--index-on-start", action="store_true",
                        help="Re-index all documents before starting server")
    parser.add_argument("--reload",         action="store_true",
                        help="Enable uvicorn auto-reload (development)")
    args = parser.parse_args()

    # ── Optional: index on startup ─────────────────────────────────────────
    if args.index_on_start:
        print("[Main] Indexing documents on startup …")
        from knowledge_api import index_docs
        index_docs(docs_dir=DOCS_DIR)

    # ── File watcher (background thread) ──────────────────────────────────
    if not args.no_watcher:
        from watcher import start_watcher_thread
        wt = start_watcher_thread(docs_dir=DOCS_DIR)
        print(f"[Main] File watcher started for: {DOCS_DIR}")

    # ── Start FastAPI ──────────────────────────────────────────────────────
    print(f"\n[Main] Starting Knowledge Agent on http://{args.host}:{args.port}")
    print("[Main] Web UI:  http://localhost:{port}".format(port=args.port))
    print("[Main] API docs: http://localhost:{port}/docs\n".format(port=args.port))

    uvicorn.run(
        "web_app:app",
        host=args.host,
        port=args.port,
        reload=args.reload,
        log_level="info",
    )


if __name__ == "__main__":
    main()