Synnefo » ./kamaki

#!/usr/bin/env python

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import codecs

class History(object):

    def __init__(self, filepath):

        self.filepath = filepath

    @classmethod

    def _match(self, line, match_terms):

        if match_terms is None:

            return True

        for term in match_terms.split():

            if term not in line:

                return False

        return True

    def get(self, match_terms=None, limit=0):

        limit = int(limit) or 0

        with codecs.open(self.filepath, mode='r', encoding='utf-8') as f:

            result = [u'%s.  \t%s' % (

                i + 1, line) for i, line in enumerate(f.readlines())

                if self._match(line, match_terms)]

            return result[- limit:]

    def add(self, line):

        with open(self.filepath, 'a+') as f:

            f.write(line + '\n')

    def clean(self):

        with open(self.filepath, 'w'):

            pass

    def retrieve(self, cmd_id):

        """

        :param cmd_id: (int) the id of the command to retrieve can be positive

            or negative, zero values are ignored

        :returns: (str) the stored command record without the id

        """

        cmd_id = int(cmd_id)

        if not cmd_id:

            return None

        with open(self.filepath) as f:

            try:

                cmd_list = f.readlines()[:-1]  # exclude current command

                return cmd_list[cmd_id - (1 if cmd_id > 0 else 0)]

            except IndexError:

                return None