# Copyright (C) 2016 Adrien Vergé
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import string

import yaml

from yamllint.linter import LintProblem


def spaces_after(token, prev, next, min=-1, max=-1,
                 min_desc=None, max_desc=None):
    if next is not None and token.end_mark.line == next.start_mark.line:
        spaces = next.start_mark.pointer - token.end_mark.pointer
        if max != - 1 and spaces > max:
            return LintProblem(token.start_mark.line + 1,
                               next.start_mark.column, max_desc)
        elif min != - 1 and spaces < min:
            return LintProblem(token.start_mark.line + 1,
                               next.start_mark.column + 1, min_desc)


def spaces_before(token, prev, next, min=-1, max=-1,
                  min_desc=None, max_desc=None):
    if (prev is not None and prev.end_mark.line == token.start_mark.line and
            # Discard tokens (only scalars?) that end at the start of next line
            (prev.end_mark.pointer == 0 or
             prev.end_mark.buffer[prev.end_mark.pointer - 1] != '\n')):
        spaces = token.start_mark.pointer - prev.end_mark.pointer
        if max != - 1 and spaces > max:
            return LintProblem(token.start_mark.line + 1,
                               token.start_mark.column, max_desc)
        elif min != - 1 and spaces < min:
            return LintProblem(token.start_mark.line + 1,
                               token.start_mark.column + 1, min_desc)


def get_line_indent(token):
    """Finds the indent of the line the token starts in."""
    start = token.start_mark.buffer.rfind('\n', 0,
                                          token.start_mark.pointer) + 1
    content = start
    while token.start_mark.buffer[content] == ' ':
        content += 1
    return content - start


def get_real_end_line(token):
    """Finds the line on which the token really ends.

    With pyyaml, scalar tokens often end on a next line.
    """
    end_line = token.end_mark.line + 1

    if not isinstance(token, yaml.ScalarToken):
        return end_line

    pos = token.end_mark.pointer - 1
    while (pos >= token.start_mark.pointer - 1 and
           token.end_mark.buffer[pos] in string.whitespace):
        if token.end_mark.buffer[pos] == '\n':
            end_line -= 1
        pos -= 1
    return end_line


def is_explicit_key(token):
    # explicit key:
    #   ? key
    #   : v
    # or
    #   ?
    #     key
    #   : v
    return (token.start_mark.pointer < token.end_mark.pointer and
            token.start_mark.buffer[token.start_mark.pointer] == '?')