# coding=utf-8
# Copyright 2015 Pants project contributors (see CONTRIBUTORS.md).
# Licensed under the Apache License, Version 2.0 (see LICENSE).

from __future__ import absolute_import, division, print_function, unicode_literals

import tokenize

from pants.contrib.python.checks.checker.common import CheckstylePlugin


# TODO(wickman) Update this to sanitize line continuation styling as we have
# disabled it from pycodestyle.py due to mismatched indentation styles.
class Indentation(CheckstylePlugin):
    """Enforce proper indentation."""

    @classmethod
    def name(cls):
        return "indentation"

    INDENT_LEVEL = 2  # the one true way

    def nits(self):
        indents = []

        for token in self.python_file.tokens:
            token_type, token_text, token_start = token[0:3]
            if token_type is tokenize.INDENT:
                last_indent = len(indents[-1]) if indents else 0
                current_indent = len(token_text)
                if current_indent - last_indent != self.INDENT_LEVEL:
                    yield self.error(
                        "T100",
                        "Indentation of {} instead of {}".format(
                            current_indent - last_indent, self.INDENT_LEVEL
                        ),
                        token_start[0],
                    )
                indents.append(token_text)
            elif token_type is tokenize.DEDENT:
                indents.pop()