#
# Copyright (C) 2009, 2012-2014 Red Hat, Inc.
# Copyright (C) 2009 Cole Robinson <crobinso@redhat.com>
#
# 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 2 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
# MA 02110-1301 USA.
#

import os
import stat
import traceback
import logging

from gi.repository import Gtk
from gi.repository import Gdk
from gi.repository import Pango

import virtinst
from virtinst import util

from .asyncjob import vmmAsyncJob
from .baseclass import vmmGObjectUI
from . import uiutil

STORAGE_ROW_CONFIRM = 0
STORAGE_ROW_CANT_DELETE = 1
STORAGE_ROW_PATH = 2
STORAGE_ROW_TARGET = 3
STORAGE_ROW_ICON_SHOW = 4
STORAGE_ROW_ICON = 5
STORAGE_ROW_ICON_SIZE = 6
STORAGE_ROW_TOOLTIP = 7


class vmmDeleteDialog(vmmGObjectUI):
    def __init__(self):
        vmmGObjectUI.__init__(self, "delete.ui", "vmm-delete")
        self.vm = None
        self.conn = None

        self.builder.connect_signals({
            "on_vmm_delete_delete_event": self.close,
            "on_delete_cancel_clicked": self.close,
            "on_delete_ok_clicked": self.finish,
            "on_delete_remove_storage_toggled": self.toggle_remove_storage,
        })
        self.bind_escape_key_close()

        self._init_state()

    def _init_state(self):
        blue = Gdk.Color.parse("#0072A8")[1]
        self.widget("header").modify_bg(Gtk.StateType.NORMAL, blue)

        prepare_storage_list(self.widget("delete-storage-list"))

    def show(self, vm, parent):
        logging.debug("Showing delete wizard")
        self.vm = vm
        self.conn = vm.conn

        self.reset_state()
        self.topwin.set_transient_for(parent)
        self.topwin.present()

    def close(self, ignore1=None, ignore2=None):
        logging.debug("Closing delete wizard")
        self.topwin.hide()
        self.vm = None
        self.conn = None
        return 1

    def _cleanup(self):
        self.vm = None
        self.conn = None

    def reset_state(self):
        # Set VM name in title'
        title_str = ("<span size='large' color='white'>%s '%s'</span>" %
                     (_("Delete"), util.xml_escape(self.vm.get_name())))
        self.widget("header-label").set_markup(title_str)

        self.topwin.resize(1, 1)
        self.widget("delete-cancel").grab_focus()

        # Show warning message if VM is running
        vm_active = self.vm.is_active()
        uiutil.set_grid_row_visible(
            self.widget("delete-warn-running-vm-box"), vm_active)

        # Enable storage removal by default
        self.widget("delete-remove-storage").set_active(True)
        self.widget("delete-remove-storage").toggled()

        populate_storage_list(self.widget("delete-storage-list"),
                              self.vm, self.conn)

    def toggle_remove_storage(self, src):
        dodel = src.get_active()
        uiutil.set_grid_row_visible(
            self.widget("delete-storage-scroll"), dodel)

    def get_paths_to_delete(self):
        del_list = self.widget("delete-storage-list")
        model = del_list.get_model()

        paths = []
        if self.widget("delete-remove-storage").get_active():
            for row in model:
                if (not row[STORAGE_ROW_CANT_DELETE] and
                    row[STORAGE_ROW_CONFIRM]):
                    paths.append(row[STORAGE_ROW_PATH])
        return paths

    def _finish_cb(self, error, details):
        self.reset_finish_cursor()

        if error is not None:
            self.err.show_err(error, details=details)

        self.conn.schedule_priority_tick(pollvm=True)
        self.close()

    def finish(self, src_ignore):
        devs = self.get_paths_to_delete()

        if devs:
            title = _("Are you sure you want to delete the storage?")
            message = (_("The following paths will be deleted:\n\n%s") %
                       "\n".join(devs))
            ret = self.err.chkbox_helper(
                self.config.get_confirm_delstorage,
                self.config.set_confirm_delstorage,
                text1=title, text2=message)
            if not ret:
                return

        self.set_finish_cursor()

        title = _("Deleting virtual machine '%s'") % self.vm.get_name()
        text = title
        if devs:
            text = title + _(" and selected storage (this may take a while)")

        progWin = vmmAsyncJob(self._async_delete, [devs],
                              self._finish_cb, [],
                              title, text, self.topwin)
        progWin.run()

    def _async_delete(self, asyncjob, paths):
        storage_errors = []
        details = ""

        try:
            if self.vm.is_active():
                logging.debug("Forcing VM '%s' power off.", self.vm.get_name())
                self.vm.destroy()

            conn = self.conn.get_backend()
            meter = asyncjob.get_meter()

            for path in paths:
                try:
                    logging.debug("Deleting path: %s", path)
                    meter.start(text=_("Deleting path '%s'") % path)
                    self._async_delete_path(conn, path, meter)
                except Exception as e:
                    storage_errors.append((str(e),
                                          "".join(traceback.format_exc())))
                meter.end(0)

            logging.debug("Removing VM '%s'", self.vm.get_name())
            self.vm.delete()

        except Exception as e:
            error = (_("Error deleting virtual machine '%s': %s") %
                      (self.vm.get_name(), str(e)))
            details = "".join(traceback.format_exc())


        storage_errstr = ""
        for errinfo in storage_errors:
            storage_errstr += "%s\n%s\n" % (errinfo[0], errinfo[1])

        if not storage_errstr and not details:
            return

        # We had extra storage errors. If there was another error message,
        # errors to it. Otherwise, build the main error around them.
        if details:
            details += "\n\n"
            details += _("Additionally, there were errors removing"
                                    " certain storage devices: \n")
            details += storage_errstr
        else:
            error = _("Errors encountered while removing certain "
                               "storage devices.")
            details = storage_errstr

        if error:
            asyncjob.set_error(error, details)

    def _async_delete_path(self, conn, path, ignore):
        vol = None

        try:
            vol = conn.storageVolLookupByPath(path)
        except Exception:
            logging.debug("Path '%s' is not managed. Deleting locally", path)

        if vol:
            vol.delete(0)
        else:
            os.unlink(path)


def populate_storage_list(storage_list, vm, conn):
    model = storage_list.get_model()
    model.clear()

    diskdata = [(d.target, d.path, d.read_only, d.shareable,
                 d.device in ["cdrom", "floppy"]) for
                d in vm.get_disk_devices()]

    diskdata.append(("kernel", vm.get_xmlobj().os.kernel, True, False, True))
    diskdata.append(("initrd", vm.get_xmlobj().os.initrd, True, False, True))
    diskdata.append(("dtb", vm.get_xmlobj().os.dtb, True, False, True))

    for target, path, ro, shared, is_media in diskdata:
        if not path:
            continue

        # There are a few pieces here
        # 1) Can we even delete the storage? If not, make the checkbox
        #    inconsistent. self.can_delete decides this for us, and if
        #    we can't delete, gives us a nice message to show the user
        #    for that row.
        #
        # 2) If we can delete, do we want to delete this storage by
        #    default? Reasons not to, are if the storage is marked
        #    readonly or shareable, or is in use by another VM.

        default = False
        definfo = None
        vol = conn.get_vol_by_path(path)
        can_del, delinfo = can_delete(conn, vol, path)

        if can_del:
            default, definfo = do_we_default(conn, vm.get_name(), vol,
                                             path, ro, shared, is_media)

        info = None
        if not can_del:
            info = delinfo
        elif not default:
            info = definfo

        icon = Gtk.STOCK_DIALOG_WARNING
        icon_size = Gtk.IconSize.LARGE_TOOLBAR

        row = [default, not can_del, path, target,
               bool(info), icon, icon_size, info]
        model.append(row)


def prepare_storage_list(storage_list):
    # Checkbox, deleteable?, storage path, target (hda), icon stock,
    # icon size, tooltip
    model = Gtk.ListStore(bool, bool, str, str, bool, str, int, str)
    storage_list.set_model(model)
    storage_list.set_tooltip_column(STORAGE_ROW_TOOLTIP)

    confirmCol = Gtk.TreeViewColumn()
    targetCol = Gtk.TreeViewColumn(_("Target"))
    infoCol = Gtk.TreeViewColumn()
    pathCol = Gtk.TreeViewColumn(_("Storage Path"))
    pathCol.set_sizing(Gtk.TreeViewColumnSizing.AUTOSIZE)
    pathCol.set_expand(True)

    storage_list.append_column(confirmCol)
    storage_list.append_column(pathCol)
    storage_list.append_column(targetCol)
    storage_list.append_column(infoCol)

    chkbox = Gtk.CellRendererToggle()
    chkbox.connect('toggled', storage_item_toggled, storage_list)
    confirmCol.pack_start(chkbox, False)
    confirmCol.add_attribute(chkbox, 'active', STORAGE_ROW_CONFIRM)
    confirmCol.add_attribute(chkbox, 'inconsistent',
                             STORAGE_ROW_CANT_DELETE)
    confirmCol.set_sort_column_id(STORAGE_ROW_CANT_DELETE)

    path_txt = Gtk.CellRendererText()
    pathCol.pack_start(path_txt, True)
    pathCol.add_attribute(path_txt, 'text', STORAGE_ROW_PATH)
    pathCol.set_sort_column_id(STORAGE_ROW_PATH)
    path_txt.set_property("width-chars", 50)
    path_txt.set_property("ellipsize", Pango.EllipsizeMode.MIDDLE)

    target_txt = Gtk.CellRendererText()
    targetCol.pack_start(target_txt, False)
    targetCol.add_attribute(target_txt, 'text', STORAGE_ROW_TARGET)
    targetCol.set_sort_column_id(STORAGE_ROW_TARGET)

    info_img = Gtk.CellRendererPixbuf()
    infoCol.pack_start(info_img, False)
    infoCol.add_attribute(info_img, 'visible', STORAGE_ROW_ICON_SHOW)
    infoCol.add_attribute(info_img, 'stock-id', STORAGE_ROW_ICON)
    infoCol.add_attribute(info_img, 'stock-size', STORAGE_ROW_ICON_SIZE)
    infoCol.set_sort_column_id(STORAGE_ROW_ICON)


def storage_item_toggled(src, index, storage_list):
    active = src.get_active()

    model = storage_list.get_model()
    model[index][STORAGE_ROW_CONFIRM] = not active


def can_delete(conn, vol, path):
    """Is the passed path even deleteable"""
    ret = True
    msg = None

    if vol:
        # Managed storage
        pool_type = vol.get_parent_pool().get_type()
        if pool_type == virtinst.StoragePool.TYPE_ISCSI:
            msg = _("Cannot delete iscsi share.")
        elif pool_type == virtinst.StoragePool.TYPE_SCSI:
            msg = _("Cannot delete SCSI device.")
    else:
        if conn.is_remote():
            msg = _("Cannot delete unmanaged remote storage.")
        elif not os.path.exists(path):
            msg = _("Path does not exist.")
        elif not os.access(os.path.dirname(path), os.W_OK):
            msg = _("No write access to parent directory.")
        elif stat.S_ISBLK(os.stat(path)[stat.ST_MODE]):
            msg = _("Cannot delete unmanaged block device.")

    if msg:
        ret = False

    return (ret, msg)


def do_we_default(conn, vm_name, vol, path, ro, shared, is_media):
    """ Returns (do we delete by default?, info string if not)"""
    info = ""

    def append_str(str1, str2, delim="\n"):
        if not str2:
            return str1
        if str1:
            str1 += delim
        str1 += str2
        return str1

    if ro:
        info = append_str(info, _("Storage is read-only."))
    elif not vol and not os.access(path, os.W_OK):
        info = append_str(info, _("No write access to path."))

    if shared:
        info = append_str(info, _("Storage is marked as shareable."))

    if not info and is_media:
        info = append_str(info, _("Storage is a media device."))

    try:
        names = virtinst.VirtualDisk.path_in_use_by(conn.get_backend(), path)

        if len(names) > 1:
            namestr = ""
            names.remove(vm_name)
            for name in names:
                namestr = append_str(namestr, name, delim="\n- ")
            info = append_str(info, _("Storage is in use by the following "
                                      "virtual machines:\n- %s " % namestr))
    except Exception as e:
        logging.exception("Failed checking disk conflict: %s", str(e))

    return (not info, info)