"""For parsing MediaWiki text, we rely on the package mwparserfromhell (https://github.com/earwig/mwparserfromhell).
This module just contains a few additional useful functions.

Other Python MediaWiki parsers:
* py-wikimarkup https://github.com/dcramer/py-wikimarkup
* mwlib http://code.pediapress.com/wiki/wiki
* https://www.mediawiki.org/wiki/Alternative_parsers
"""


class ParseError(RuntimeError):
    """Exception used by some of the functions"""
    pass


def format_template_table(template, keylen=None):
    """Reformat the given template to be tabular.

    >>> template
    {{foo|bar|bazz=7}}
    >>> format_template_table(template)
    {{foo
    | bar
    | bazz = 7
    }}

    :param keylen: length of the keys or None for automatic determination
    """
    if keylen is None:
        shown_keys = [len(param.name.strip()) for param in template.params if param.showkey]
        keylen = max(shown_keys) if shown_keys else 0
    template.name = '{}\n'.format(template.name.strip())
    for param in template.params:
        if param.showkey:
            param.name = ' {{:{}}} '.format(keylen).format(param.name.strip())
        value = param.value.strip()
        if len(value) > 0:
            param.value = ' {}\n'.format(value)
        else:
            param.value = '\n'


def format_template_oneline(template):
    """Formats a template like this: {{template_name|param| }}
    (whitespace is stripped and empty parameters are replaced with one space)."""
    template.name = template.name.strip()
    for param in template.params:
        if param.showkey:
            param.name = param.name.strip()
        value = param.value.strip()
        if value == '':
            value = ' '
        param.value = value


def dbkey_to_title(value):
    """Converts a article database key to a article title. Private function secureAndSplit() of the Title class
    on line 3316 of includes/Title.php says:
    $this->mTextform = str_replace( '_', ' ', $this->mDbkeyform );
    No check for None because a missing title is an error."""
    return value.replace('_', ' ')