from time import time
import os
from ..conf import settings
from ..const import ARGUMENT_PLACEHOLDER
from ..utils import memoize
from .generic import Generic


class Zsh(Generic):
    def app_alias(self, alias_name):
        # It is VERY important to have the variables declared WITHIN the function
        return '''
            {name} () {{
                TF_PREVIOUS=$(fc -ln -1 | tail -n 1);
                TF_CMD=$(
                    TF_ALIAS={name}
                    TF_SHELL_ALIASES=$(alias)
                    PYTHONIOENCODING=utf-8
                    thefuck $TF_PREVIOUS {argument_placeholder} $*
                ) && eval $TF_CMD;
                {alter_history}
            }}
        '''.format(
            name=alias_name,
            argument_placeholder=ARGUMENT_PLACEHOLDER,
            alter_history=('test -n "$TF_CMD" && print -s $TF_CMD'
                           if settings.alter_history else ''))

    def _parse_alias(self, alias):
        name, value = alias.split('=', 1)
        if value[0] == value[-1] == '"' or value[0] == value[-1] == "'":
            value = value[1:-1]
        return name, value

    @memoize
    def get_aliases(self):
        raw_aliases = os.environ.get('TF_SHELL_ALIASES', '').split('\n')
        return dict(self._parse_alias(alias)
                    for alias in raw_aliases if alias and '=' in alias)

    def _get_history_file_name(self):
        return os.environ.get("HISTFILE",
                              os.path.expanduser('~/.zsh_history'))

    def _get_history_line(self, command_script):
        return u': {}:0;{}\n'.format(int(time()), command_script)

    def _script_from_history(self, line):
        if ';' in line:
            return line.split(';', 1)[1]
        else:
            return ''

    def how_to_configure(self):
        return self._create_shell_configuration(
            content=u'eval $(thefuck --alias)',
            path='~/.zshrc',
            reload='source ~/.zshrc')
