#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright (C) 2015 GNS3 Technologies Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.


import json
import sys
import os
from gns3registry.image import Image


class ConfigException(Exception):
    pass


class Config:
    """
    GNS3 config file
    """

    def __init__(self, path=None):
        """
        :params path: Path of the configuration file otherwise detect it on the system
        """

        #TODO: Manage errors
        self.path = path
        if self.path is None:
            self.path = self._get_standard_config_file_path()

        with open(self.path) as f:
            self._config = json.load(f)

    @property
    def images_dir(self):
        """
        :returns: Localion of the images directory on the server
        """
        return self._config["LocalServer"]["images_path"]

    def _get_standard_config_file_path(self):
        if sys.platform.startswith("win"):
            filename = "gns3_gui.ini"
        else:
            filename = "gns3_gui.conf"

        if sys.platform.startswith("darwin"):
            appname = "gns3.net"
        else:
            appname = "GNS3"

        if sys.platform.startswith("win"):
            appdata = os.path.expandvars("%APPDATA%")
            return os.path.join(appdata, appname, filename)
        else:
            home = os.path.expanduser("~")
            return os.path.join(home, ".config", appname, filename)

    def add_images(self, device_config):
        """
        Add images to the user configuration
        """
        new_config = {
            "server": "local",
            "name": device_config["name"]
        }
        if device_config["category"] == "guest":
            new_config["category"] = 2
        elif device_config["category"] == "router":
            new_config["category"] = 0

        if "qemu" in device_config:
            self._add_qemu_config(new_config, device_config)

    def _add_qemu_config(self, new_config, device_config):

        new_config["adapter_type"] = device_config["qemu"]["adapter_type"]
        new_config["adapters"] = device_config["qemu"]["adapters"]
        new_config["cpu_throttling"] = 0
        new_config["ram"] = device_config["qemu"]["ram"]
        new_config["legacy_networking"] = False
        new_config["process_priority"] = "normal"

        new_config["initrd"] = ""
        new_config["kernel_command_line"] = ""
        new_config["kernel_image"] = ""
        new_config["options"] = ""
        new_config["hdb_disk_image"] = ""
        new_config["hdc_disk_image"] = ""
        new_config["hdd_disk_image"] = ""

        #TODO: Manage Windows
        if device_config["qemu"]["processor"] == "i386":
            new_config["qemu_path"] = "qemu-system-i386"
        elif device_config["qemu"]["processor"] == "x64":
            new_config["qemu_path"] = "qemu-system-x86_64"

        if device_config["category"] == "guest":
            new_config["default_symbol"] = ":/symbols/qemu_guest.normal.svg"
            new_config["hover_symbol"] = ":/symbols/qemu_guest.selected.svg"
        elif device_config["category"] == "router":
            new_config["default_symbol"] = ":/symbols/router.normal.svg"
            new_config["hover_symbol"] = ":/symbols/router.selected.svg"

        disks = ["hda_disk_image", "hdb_disk_image", "hdc_disk_image", "hdd_disk_image"]
        for disk in disks:
            if disk in device_config["images"]:
                if isinstance(device_config["images"][disk], list):
                    require_images = ""
                    for image in device_config["images"][disk]:
                        require_images += "* {}\n".format(image["filename"])
                        raise ConfigException("Missing image for {} you should provide one of the following images:\n{}".format(disk, require_images))
                else:
                    new_config["name"] += " {}".format(device_config["images"][disk].version)
                    new_config[disk] = device_config["images"][disk].path

        # Remove VM with the same Name
        self._config["Qemu"]["vms"] = [item for item in self._config["Qemu"]["vms"] if item["name"] != new_config["name"]]

        self._config["Qemu"]["vms"].append(new_config)

    def save(self):
        """
        Save the configuration file
        """
        with open(self.path, "w+") as f:
            json.dump(self._config, f, indent=4)