from typing import Dict, Any, List
import re


class RuleValidator:
    REQUIRED_FIELDS = ['id', 'name', 'pattern', 'fix', 'description']
    OPTIONAL_FIELDS = ['severity', 'language', 'tool', 'tags', 'priority', 'metadata']

    def validate(self, data: Dict[str, Any]) -> bool:
        missing = [field for field in self.REQUIRED_FIELDS if field not in data]
        if missing:
            raise ValueError(f"Missing required fields: {', '.join(missing)}")

        for field in data:
            if field not in self.REQUIRED_FIELDS + self.OPTIONAL_FIELDS:
                raise ValueError(f"Unknown field: {field}")

        self._validate_pattern(data['pattern'])
        self._validate_severity(data.get('severity', 'error'))
        self._validate_priority(data.get('priority', 0))

        return True

    def _validate_pattern(self, pattern: str) -> None:
        if not isinstance(pattern, str):
            raise ValueError("Pattern must be a string")
        if not pattern.strip():
            raise ValueError("Pattern cannot be empty")
        try:
            re.compile(pattern)
        except re.error as e:
            raise ValueError(f"Invalid regex pattern: {e}")

    def _validate_severity(self, severity: str) -> None:
        valid_severities = ['error', 'warning', 'info', 'suggestion']
        if severity not in valid_severities:
            raise ValueError(f"Invalid severity: {severity}. Must be one of {valid_severities}")

    def _validate_priority(self, priority: int) -> None:
        if not isinstance(priority, int):
            raise ValueError("Priority must be an integer")
        if priority < 0:
            raise ValueError("Priority must be non-negative")