"""Arma 3 RPT log parser."""
from __future__ import annotations

import re
from datetime import datetime
from pathlib import Path
from typing import Callable


class RPTParser:
    """Parses Arma 3 .rpt log files."""

    # Pattern: "HH:MM:SS ..." or "[HH:MM:SS] ..." with optional date prefix
    _timestamp_re = re.compile(
        r"^\s*(?:(\d{2}/\d{2}/\d{4})\s+)?"
        r"(?:\[)?(\d{2}:\d{2}:\d{2})(?:\])?\s*"
        r"(?:\[?(\w+)\]?\s*)?(.*)$"
    )

    def parse_line(self, line: str) -> dict | None:
        """Parse one RPT log line."""
        if not line or not line.strip():
            return None

        match = self._timestamp_re.match(line)
        if not match:
            # Non-timestamped line — treat as info
            stripped = line.strip()
            if not stripped:
                return None
            return {
                "timestamp": datetime.utcnow().isoformat(),
                "level": "info",
                "message": stripped,
            }

        date_str, time_str, level_str, message = match.groups()

        # Map Arma 3 log levels
        level = "info"
        if level_str:
            level_lower = level_str.lower()
            if level_lower in ("error", "fault"):
                level = "error"
            elif level_lower in ("warning", "warn"):
                level = "warning"

        # Build ISO timestamp
        try:
            if date_str:
                dt = datetime.strptime(f"{date_str} {time_str}", "%m/%d/%Y %H:%M:%S")
            else:
                dt = datetime.strptime(time_str, "%H:%M:%S")
                dt = dt.replace(year=datetime.utcnow().year, month=datetime.utcnow().month, day=datetime.utcnow().day)
            timestamp = dt.isoformat()
        except ValueError:
            timestamp = datetime.utcnow().isoformat()

        return {
            "timestamp": timestamp,
            "level": level,
            "message": (message or "").strip(),
        }

    def get_log_file_resolver(self, server_id: int) -> Callable[[Path], Path | None]:
        """Return a callable that finds the current RPT log file."""
        def resolver(server_dir: Path) -> Path | None:
            # Arma 3 stores logs in server_dir/server/*.rpt
            profile_dir = server_dir / "server"
            if not profile_dir.exists():
                return None

            rpt_files = sorted(profile_dir.glob("*.rpt"), key=lambda p: p.stat().st_mtime, reverse=True)
            if rpt_files:
                return rpt_files[0]

            # Fallback: check for arma3server_x64_*.rpt pattern
            rpt_files = sorted(profile_dir.glob("arma3server*.rpt"), key=lambda p: p.stat().st_mtime, reverse=True)
            return rpt_files[0] if rpt_files else None

        return resolver