"""Parses a response string to extract expressions based on specific patterns.

This function processes a multi-line response string, extracting expressions that follow the pattern:
'当"<situation>" 使用"<style>"'. Each valid expression is captured as a tuple containing the chat ID,
the situation, and the style. The function skips empty lines and lines that do not match the expected pattern.

Args:
    response (str): The multi-line string response to be parsed.
    chat_id (str): The chat ID to be included in each extracted expression tuple.

Returns:
    List[Tuple[str, str, str]]: A list of tuples, where each tuple contains the chat ID, situation, and style
    extracted from the response. If no valid expressions are found, an empty list is returned.

Example:
    >>> parse_expression_response('当"情况1" 使用"风格1"', 'chat1')
    [('chat1', '情况1', '风格1')]
    >>> parse_expression_response('当"情况1" 使用"风格1"\n当"情况2" 使用"风格2"', 'chat2')
    [('chat2', '情况1', '风格1'), ('chat2', '情况2', '风格2')]
"""