"""
Professional time parsing module for Chinese and English time expressions.

This module provides a robust parser for natural language time expressions,
supporting both Chinese and English formats with proper whitespace handling.
"""

import datetime
from typing import Optional

from .expression import TimeExpression


def parse(text: str, now: Optional[datetime.datetime] = None) -> datetime.datetime:
    """
    Parse a time expression and return a datetime object.
    
    Args:
        text: The time expression to parse
        now: The reference time (defaults to current time)
        
    Returns:
        A datetime object representing the parsed time
        
    Raises:
        TokenUnhandledException: If the input cannot be parsed
    """
    return TimeExpression.parse(text, now)


class Parser:
    """
    Parser for time expressions with backward compatibility.
    
    Maintains the original interface:
    >>> parser = Parser()
    >>> result = parser.parse("10分钟后")
    """
    
    def __init__(self, now: Optional[datetime.datetime] = None):
        self.now = now or datetime.datetime.now()
    
    def parse(self, text: str) -> datetime.datetime:
        """
        Parse a time expression and return a datetime object.
        This maintains backward compatibility with the original interface.
        
        Args:
            text: The time expression to parse
            
        Returns:
            A datetime object representing the parsed time
            
        Raises:
            TokenUnhandledException: If the input cannot be parsed
        """
        return TimeExpression.parse(text, self.now)