from typing import Optional


class SeverityClassifier:
    """Classify log entry severity based on content and level."""

    def classify(self, message: str, level: Optional[str]) -> str:
        """Classify the severity of a log entry."""
        if level:
            level_lower = level.lower()
            if level_lower in ("critical", "fatal", "emerg"):
                return "critical"
            elif level_lower in ("error", "err", "erro"):
                return "error"
            elif level_lower in ("warning", "warn"):
                return "warning"
            elif level_lower in ("info", "informational"):
                return "info"
            elif level_lower in ("debug", "dbg", "trace"):
                return "debug"

        message_lower = message.lower()

        critical_keywords = [
            "fatal",
            "panic",
            "crash",
            "died",
            "terminated",
            "segfault",
            "out of memory",
            "no space left",
        ]
        error_keywords = [
            "error",
            "fail",
            "exception",
            "invalid",
            "cannot",
            "unable",
            "timeout",
            "refused",
            "rejected",
        ]
        warning_keywords = ["warning", "warn", "deprecated", "slow", "high latency"]
        debug_keywords = ["debug", "trace", "verbose", "dump", "print"]

        for keyword in critical_keywords:
            if keyword in message_lower:
                return "critical"

        for keyword in error_keywords:
            if keyword in message_lower:
                return "error"

        for keyword in warning_keywords:
            if keyword in message_lower:
                return "warning"

        for keyword in debug_keywords:
            if keyword in message_lower:
                return "debug"

        return "info"