#!/usr/bin/env python3
import os
import sys

import yaml


ALACRITTY_CONFIG = os.path.expanduser("~/.config/alacritty/alacritty.yml")


class Action:
    mutating = False
    def __init__(self, path):
        self.path = path

    def traverse(self, yml):
        for p in self.path:
            yml = yml[p]
        return yml


class ShowAction(Action):
    def act_on(self, yml):
        yml = self.traverse(yml)
        if type(yml) is dict:
            print(yaml.dump(yml))
        else:
            print(yml)


class EditAction(Action):
    mutating = True
    def __init__(self, path):
        self.path = path[:-1]
        self.prop = path[-1]


class AddAction(EditAction):
    def __init__(self, path, val):
        super().__init__(path)
        self.val = yaml.safe_load(val)

    def act_on(self, yml):
        yml = self.traverse(yml)
        yml[self.prop] = self.val


class DeleteAction(EditAction):
    def act_on(self, yml):
        yml = self.traverse(yml)
        del yml[self.prop]


def parse_path(p):
    if p.isdigit():
        return int(p)
    return p


def parse_action():
    args = sys.argv

    if len(args) == 1:
        return ShowAction([])

    path = [parse_path(a) for a in args[1].split('.')]
    if len(args) == 2:
        return ShowAction(path)

    if len(args) == 3 and args[2] == '--delete':
        return DeleteAction(path)

    return AddAction(path, args[2])


def main():
    action = parse_action()

    try:
        with open(ALACRITTY_CONFIG) as f:
            y = yaml.safe_load(f.read())
            action.act_on(y)
        if action.mutating:
            with open(ALACRITTY_CONFIG, "w+") as f:
                f.write(yaml.dump(y))
    except KeyError as e:
        print('Key "{}" was not found in alacritty config!'.format(e))


if __name__ == '__main__':
    main()