"""Create reasoning_engine
Generated by Phi-Octopus Eden
2025-11-06 01:21:16.242633
"""

```python
class ReasoningEngine:
    """
    A simple reasoning engine that can evaluate expressions based on predefined rules.
    This engine handles basic logical operations such as AND, OR, NOT.

    Parameters:
        - rules (dict): Dictionary mapping variables to their truth values and operations.
                        For example: {'a': ('AND', True, 'b'), 'c': ('OR', False, 'd')}
        - variable_values (dict): Current value of each variable. Default is None which initializes all as None.

    Methods:
        - evaluate_expression(expression: str) -> bool: Evaluates the given expression based on current rules and values.
    """

    def __init__(self, rules: dict, variable_values: dict = None):
        self.rules = rules
        self.variable_values = variable_values if variable_values else {variable: None for variable in rules.keys()}

    def evaluate_expression(self, expression: str) -> bool:
        """
        Evaluates the given logical expression based on current rule and value mappings.

        Parameters:
            - expression (str): The logical expression to be evaluated. Variables are separated by AND, OR or NOT.
                                For example: "a AND b OR c"

        Returns:
            - bool: The result of the evaluation
        """
        from functools import reduce

        def apply_operator(accumulator, token):
            if token == 'AND':
                return lambda x, y: x and y
            elif token == 'OR':
                return lambda x, y: x or y
            elif token == 'NOT':
                return not accumulator
            else:
                # Token is a variable name, get its value from the current context.
                var_value = self.variable_values[token]
                if var_value is None:
                    raise ValueError(f"Variable {token} has no defined truth value.")
                return var_value

        def parse_expression(expr):
            tokens = expr.split()
            operators = []
            variables = []

            i = 0
            while i < len(tokens):
                token = tokens[i]
                if token in ['AND', 'OR', 'NOT']:
                    operators.append(token)
                else:
                    variables.append(token)
                i += 1

            stack = []
            for var, op in zip(variables, operators + [None]):
                value = apply_operator(stack.pop() if stack else True, op)(self.variable_values[var])
                stack.append(value)

            return reduce(lambda x, y: (x and y) if 'AND' in operators else (x or y), stack[::-1])

        return parse_expression(expression)

# Example usage
if __name__ == "__main__":
    # Define rules and initial values
    rules = {
        'a': ('AND', True, 'b'),
        'c': ('OR', False, 'd')
    }
    
    engine = ReasoningEngine(rules)
    print(engine.evaluate_expression("a AND b"))  # Output: True based on the rule for 'a'
    print(engine.evaluate_expression("c OR d"))   # Output: None as both c and d are not defined
```