# Copyright 2017 the authors.
# This file is part of Hy, which is free software licensed under the Expat
# license. See the LICENSE.

from hy.errors import HyError


class LexException(HyError):
    """Error during the Lexing of a Hython expression."""
    def __init__(self, message, lineno, colno, source=None):
        super(LexException, self).__init__(message)
        self.message = message
        self.lineno = lineno
        self.colno = colno
        self.source = source
        self.filename = '<stdin>'

    def __str__(self):
        from hy.errors import colored

        line = self.lineno
        start = self.colno

        result = ""

        source = self.source.split("\n")

        if line > 0 and start > 0:
            result += '  File "%s", line %d, column %d\n\n' % (self.filename,
                                                               line,
                                                               start)

            if len(self.source) > 0:
                source_line = source[line-1]
            else:
                source_line = ""

            result += '  %s\n' % colored.red(source_line)
            result += '  %s%s\n' % (' '*(start-1), colored.green('^'))

        result += colored.yellow("LexException: %s\n\n" % self.message)

        return result


class PrematureEndOfInput(LexException):
    """We got a premature end of input"""
    def __init__(self, message):
        super(PrematureEndOfInput, self).__init__(message, -1, -1)
