"""CLI entry point that launches the evaluation console web server.

Run alongside the existing main.py CLI; both share the same rag_eval library
and the same runs/ artifacts. Example:

    python webmain.py
    python webmain.py --host 0.0.0.0 --port 8800
    python webmain.py --host 0.0.0.0 --port 8800 --log-level debug
"""

from __future__ import annotations

import argparse
import logging
import logging.config
from datetime import datetime
from pathlib import Path


REPO_ROOT = Path(__file__).resolve().parent


def _build_log_config(log_file: Path, level: str) -> dict:
    """Build a uvicorn-compatible logging config dict.

    Writes to both stderr (console) and a rotating daily log file.
    All webapp.* and rag_eval.* loggers inherit from root so every
    logger.info() call in the API routes is captured.
    """
    level_upper = level.upper()
    return {
        "version": 1,
        "disable_existing_loggers": False,
        "formatters": {
            "detailed": {
                "format": "%(asctime)s  %(levelname)-8s  %(name)s  %(message)s",
                "datefmt": "%Y-%m-%d %H:%M:%S",
            },
            "console": {
                "format": "%(asctime)s  %(levelname)-8s  %(name)-30s  %(message)s",
                "datefmt": "%H:%M:%S",
            },
        },
        "handlers": {
            "console": {
                "class": "logging.StreamHandler",
                "stream": "ext://sys.stderr",
                "formatter": "console",
                "level": level_upper,
            },
            "file": {
                "class": "logging.handlers.RotatingFileHandler",
                "filename": str(log_file),
                "maxBytes": 50 * 1024 * 1024,   # 50 MB per file
                "backupCount": 7,                 # keep 7 rotated files
                "encoding": "utf-8",
                "formatter": "detailed",
                "level": "DEBUG",                 # file always captures everything
            },
        },
        "loggers": {
            # Our application loggers — detailed level
            "webapp": {"handlers": ["console", "file"], "level": level_upper, "propagate": False},
            "rag_eval": {"handlers": ["console", "file"], "level": level_upper, "propagate": False},
            # uvicorn access log — captured to file, shown on console
            "uvicorn.access": {"handlers": ["console", "file"], "level": "INFO", "propagate": False},
            "uvicorn.error": {"handlers": ["console", "file"], "level": "INFO", "propagate": False},
            "uvicorn": {"handlers": ["console", "file"], "level": "INFO", "propagate": False},
        },
        "root": {
            "handlers": ["console", "file"],
            "level": "WARNING",   # suppress noisy third-party libs at WARNING
        },
    }


def parse_args() -> argparse.Namespace:
    """Parse host/port/reload options for the console server."""
    parser = argparse.ArgumentParser(description="Launch the RAGAS evaluation console.")
    parser.add_argument("--host", default="127.0.0.1", help="Bind host (default 127.0.0.1).")
    parser.add_argument("--port", type=int, default=8800, help="Bind port (default 8800).")
    parser.add_argument(
        "--reload",
        action="store_true",
        help="Enable auto-reload for local development.",
    )
    parser.add_argument(
        "--log-level",
        default="info",
        choices=["debug", "info", "warning", "error"],
        help="Console log level (default: info). File always captures DEBUG.",
    )
    parser.add_argument(
        "--log-file",
        default=None,
        help="Log file path (default: logs/server_YYYY-MM-DD.log).",
    )
    return parser.parse_args()


def main() -> None:
    """Start uvicorn with the configured application and logging."""
    import uvicorn

    args = parse_args()

    # Resolve log file path
    logs_dir = REPO_ROOT / "logs"
    logs_dir.mkdir(parents=True, exist_ok=True)
    if args.log_file:
        log_file = Path(args.log_file)
    else:
        date_str = datetime.now().strftime("%Y-%m-%d")
        log_file = logs_dir / f"server_{date_str}.log"

    log_config = _build_log_config(log_file, args.log_level)

    # Apply config before uvicorn starts so our loggers are ready immediately
    logging.config.dictConfig(log_config)

    logger = logging.getLogger("webapp.server")
    logger.info(
        "Starting RAGAS Console  host=%s  port=%d  log_level=%s  log_file=%s",
        args.host, args.port, args.log_level, log_file,
    )

    uvicorn.run(
        "webapp.server:app",
        host=args.host,
        port=args.port,
        reload=args.reload,
        log_config=log_config,   # hand our config to uvicorn so it uses same handlers
    )


if __name__ == "__main__":
    main()