# Copyright (C) 2009-2013  Roman Zimbelmann <hut@lavabit.com>
# This software is distributed under the terms of the GNU GPL version 3.

from inspect import isfunction
from ranger.ext.signals import SignalDispatcher, Signal
from ranger.core.shared import FileManagerAware
from ranger.gui.colorscheme import _colorscheme_name_to_class
import re
import os

ALLOWED_SETTINGS = {
    'autosave_bookmarks': bool,
    'autoupdate_cumulative_size': bool,
    'collapse_preview': bool,
    'colorscheme': str,
    'column_ratios': (tuple, list),
    'confirm_on_delete': str,
    'dirname_in_tabs': bool,
    'display_size_in_main_column': bool,
    'display_size_in_status_bar': bool,
    'display_tags_in_all_columns': bool,
    'draw_borders': bool,
    'draw_progress_bar_in_status_bar': bool,
    'flushinput': bool,
    'hidden_filter': str,
    'max_console_history_size': (int, type(None)),
    'max_history_size': (int, type(None)),
    'mouse_enabled': bool,
    'padding_right': bool,
    'preview_directories': bool,
    'preview_files': bool,
    'preview_images': bool,
    'preview_script': (str, type(None)),
    'save_console_history': bool,
    'scroll_offset': int,
    'shorten_title': int,
    'show_cursor': bool,  # TODO: not working?
    'show_hidden_bookmarks': bool,
    'show_hidden': bool,
    'sort_case_insensitive': bool,
    'sort_directories_first': bool,
    'sort_reverse': bool,
    'sort': str,
    'status_bar_on_top': bool,
    'open_all_images': bool,
    'tilde_in_titlebar': bool,
    'unicode_ellipsis': bool,
    'update_title': bool,
    'update_tmux_title': bool,
    'use_preview_script': bool,
    'vcs_aware': bool,
    'vcs_backend_git': str,
    'vcs_backend_hg': str,
    'vcs_backend_bzr': str,
    'xterm_alt_key': bool,
}

DEFAULT_VALUES = {
    bool: False,
    type(None): None,
    str: "",
    int: 0,
    list: [],
    tuple: tuple([]),
}

class Settings(SignalDispatcher, FileManagerAware):
    def __init__(self):
        SignalDispatcher.__init__(self)
        self.__dict__['_localsettings'] = dict()
        self.__dict__['_settings'] = dict()
        for name in ALLOWED_SETTINGS:
            self.signal_bind('setopt.'+name,
                    self._raw_set_with_signal, priority=0.2)

    def _sanitize(self, name, value):
        if name == 'column_ratios':
            # TODO: cover more cases here
            if isinstance(value, tuple):
                return list(value)
            if not isinstance(value, list) or len(value) < 2:
                return [1, 1]
            else:
                return [int(i) if str(i).isdigit() else 1 for i in value]

        elif name == 'colorscheme':
            signal = Signal(value=value, previous="Penis", fm=self.fm)
            _colorscheme_name_to_class(signal)
            return signal.value

        elif name == 'preview_script':
            if isinstance(value, str):
                result = os.path.expanduser(value)
                if os.path.exists(result):
                    return result
                return None

        elif name == 'use_preview_script':
            if self._settings['preview_script'] is None and value \
                    and self.fm.ui.is_on:
                self.fm.notify("Preview script undefined or not found!",
                        bad=True)

        # fallback:
        return value

    def set(self, name, value, path=None):
        assert name in ALLOWED_SETTINGS, "No such setting: {0}!".format(name)
        if name not in self._settings:
            previous = None
        else:
            previous=self._settings[name]
        assert self._check_type(name, value)
        kws = dict(setting=name, value=value, previous=previous, path=path, fm=self.fm)
        self.signal_emit('setopt', **kws)
        self.signal_emit('setopt.'+name, **kws)

    def get(self, name, path=None):
        assert name in ALLOWED_SETTINGS, "No such setting: {0}!".format(name)
        if path and path in self._localsettings and name in self._localsettings[path]:
            return self._localsettings[path][name]
        elif name in self._settings:
            return self._settings[name]
        else:
            type_ = self.types_of(name)[0]
            value = DEFAULT_VALUES[type_]
            self._raw_set(name, value, None)
            self.__setattr__(name, value)
            return self._settings[name]

    def __setattr__(self, name, value):
        if name.startswith('_'):
            self.__dict__[name] = value
        else:
            self.set(name, value, None)

    def __getattr__(self, name):
        if name.startswith('_'):
            return self.__dict__[name]
        else:
            return self.get(name, None)

    def __iter__(self):
        for x in self._settings:
            yield x

    def types_of(self, name):
        try:
            typ = ALLOWED_SETTINGS[name]
        except KeyError:
            return tuple()
        else:
            if isinstance(typ, tuple):
                return typ
            else:
                return (typ, )


    def _check_type(self, name, value):
        typ = ALLOWED_SETTINGS[name]
        if isfunction(typ):
            assert typ(value), \
                "Warning: The option `" + name + "' has an incorrect type!"
        else:
            assert isinstance(value, typ), \
                "Warning: The option `" + name + "' has an incorrect type!"\
                " Got " + str(type(value)) + ", expected " + str(typ) + "!" +\
                " Please check if your commands.py is up to date." if not \
                self.fm.ui.is_set_up else ""
        return True

    __getitem__ = __getattr__
    __setitem__ = __setattr__

    def _raw_set(self, name, value, path):
        value = self._sanitize(name, value)
        if path:
            if not path in self._localsettings:
                self._localsettings[path] = dict()
            self._localsettings[path][name] = value

            # make sure name is in _settings, so __iter__ runs through local settigns too.
            if not name in self._settings:
                type_ = self.types_of(name)[0]
                value = DEFAULT_VALUES[type_]
                self._settings[name] = value
        else:
            self._settings[name] = value

    def _raw_set_with_signal(self, signal):
        self._raw_set(signal.setting, signal.value, signal.path)


class LocalSettings():
    def __init__(self, path, parent):
        self.__dict__['_parent'] = parent
        self.__dict__['_path'] = path

    def __setattr__(self, name, value):
        if name.startswith('_'):
            self.__dict__[name] = value
        else:
            self._parent.set(name, value, self._path)

    def __getattr__(self, name):
        if name.startswith('_'):
            return self.__dict__[name]
        else:
            return self._parent.get(name, self._path)

    def __iter__(self):
        for x in self._parent._settings:
            yield x

    __getitem__ = __getattr__
    __setitem__ = __setattr__