dotfiles/gnome/.local/share/gnome-shell/extensions/forge@jmmaranan.com/lib/extension/window.js

/*
 * This file is part of the Forge extension for GNOME
 *
 * 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/>.
 *
 */

// Gnome imports
import GLib from "gi://GLib";
import Clutter from "gi://Clutter";
import GObject from "gi://GObject";
import Meta from "gi://Meta";
import St from "gi://St";

// Gnome Shell imports
import { gettext as _ } from "resource:///org/gnome/shell/extensions/extension.js";
import * as Main from "resource:///org/gnome/shell/ui/main.js";
import { PACKAGE_VERSION } from "resource:///org/gnome/shell/misc/config.js";

// Shared state
import { Logger } from "../shared/logger.js";

// App imports
import * as Utils from "./utils.js";
import { Keybindings } from "./keybindings.js";
import {
  Tree,
  Queue,
  Node,
  POSITION,
  LAYOUT_TYPES,
  ORIENTATION_TYPES,
  NODE_TYPES,
} from "./tree.js";
import { production } from "../shared/settings.js";

/** @typedef {import('../../extension.js').default} ForgeExtension */

export const WINDOW_MODES = Utils.createEnum(["FLOAT", "TILE", "GRAB_TILE", "DEFAULT"]);

// Simplify the grab modes
export const GRAB_TYPES = Utils.createEnum(["RESIZING", "MOVING", "UNKNOWN"]);

export class WindowManager extends GObject.Object {
  static {
    GObject.registerClass(this);
  }

  /** @type {ForgeExtension} */
  ext;

  /** @param {ForgeExtension} ext */
  constructor(ext) {
    super();
    this.ext = ext;
    this.prefsTitle = `Forge ${_("Settings")} - ${
      !production ? "DEV" : `${PACKAGE_VERSION}-${ext.metadata.version}`
    }`;
    this.windowProps = this.ext.configMgr.windowProps;
    this._kbd = this.ext.keybindings;
    this._tree = new Tree(this);
    this.eventQueue = new Queue();
    this.theme = this.ext.theme;
    Logger.info("forge initialized");
  }

  addFloatOverride(metaWindow, byClass = true) {
    let overrides = this.windowProps.overrides;
    let wmTitle = metaWindow.get_title();
    let wmClass = metaWindow.get_wm_class();

    for (let override in overrides) {
      if (!byClass) {
        if (override.wmClass === wmClass && override.wmTitle === wmTitle) return;
      } else {
        if (override.wmClass === wmClass && !override.wmTitle) return;
      }
    }
    overrides.push({
      wmClass: wmClass,
      wmTitle: !byClass ? wmTitle : undefined,
      mode: "float",
    });
    this.windowProps.overrides = overrides;
    this.ext.configMgr.windowProps = this.windowProps;
  }

  removeFloatOverride(metaWindow, byClass = true) {
    let overrides = this.windowProps.overrides;
    let wmTitle = metaWindow.get_title();
    let wmClass = metaWindow.get_wm_class();

    if (byClass) {
      // remove purely wmClass - by checking also if override title exists
      overrides = overrides.filter(
        (override) => !(override.wmClass === wmClass) && !override.wmTitle
      );
    } else {
      overrides = overrides.filter(
        (override) => !(override.wmClass === wmClass && override.wmTitle === wmTitle)
      );
    }

    this.windowProps.overrides = overrides;
    this.ext.configMgr.windowProps = this.windowProps;
  }

  toggleFloatingMode(action, metaWindow) {
    let nodeWindow = this.findNodeWindow(metaWindow);
    if (!nodeWindow || !(action || action.mode)) return;
    if (nodeWindow.nodeType !== NODE_TYPES.WINDOW) return;

    let floatToggle = action.name === "FloatToggle";
    let floatClassToggle = action.name === "FloatClassToggle";
    let floatingExempt = this.isFloatingExempt(metaWindow);

    if (floatingExempt) {
      if (floatClassToggle) {
        this.removeFloatOverride(metaWindow);
      } else if (floatToggle) {
        this.removeFloatOverride(metaWindow, false);
      }
      nodeWindow.mode = WINDOW_MODES.TILE;
      if (!this.isActiveWindowWorkspaceTiled(metaWindow)) {
        nodeWindow.mode = WINDOW_MODES.FLOAT;
      }
    } else {
      if (floatClassToggle) {
        this.addFloatOverride(metaWindow);
      } else if (floatToggle) {
        this.addFloatOverride(metaWindow, false);
      }
      nodeWindow.mode = WINDOW_MODES.FLOAT;
    }
  }

  queueEvent(eventObj, interval = 220) {
    this.eventQueue.enqueue(eventObj);

    if (!this._queueSourceId) {
      this._queueSourceId = GLib.timeout_add(GLib.PRIORITY_DEFAULT, interval, () => {
        const currEventObj = this.eventQueue.dequeue();
        if (currEventObj) {
          currEventObj.callback();
        }
        const result = this.eventQueue.length !== 0;
        if (!result) {
          this._queueSourceId = 0;
        }
        return result;
      });
    }
  }

  /**
   * This is the central place to bind all the non-window signals.
   */
  _bindSignals() {
    if (this._signalsBound) return;

    const display = global.display;
    const shellWm = global.window_manager;

    this._displaySignals = [
      display.connect("window-created", this.trackWindow.bind(this)),
      display.connect("grab-op-begin", this._handleGrabOpBegin.bind(this)),
      display.connect("window-entered-monitor", (_, monitor, metaWindow) => {
        this.updateMetaWorkspaceMonitor("window-entered-monitor", monitor, metaWindow);
        this.trackCurrentMonWs();
      }),
      display.connect("grab-op-end", this._handleGrabOpEnd.bind(this)),
      display.connect("showing-desktop-changed", () => {
        this.hideWindowBorders();
        this.updateDecorationLayout();
      }),
      display.connect("in-fullscreen-changed", () => {
        this.renderTree("full-screen-changed");
      }),
      display.connect("workareas-changed", (_display) => {
        if (global.display.get_n_monitors() == 0) {
          Logger.debug(`workareas-changed: no monitors, ignoring signal`);
          return;
        }
        if (this.tree.getNodeByType("WINDOW").length > 0) {
          let workspaceReload = this.workspaceAdded || this.workspaceRemoved;
          if (workspaceReload) {
            this.trackCurrentWindows();
            this.workspaceRemoved = false;
            this.workspaceAdded = false;
          } else {
            this.renderTree("workareas-changed");
          }
        }
      }),
    ];

    this._windowManagerSignals = [
      shellWm.connect("minimize", () => {
        this.hideWindowBorders();
        let focusNodeWindow = this.tree.findNode(this.focusMetaWindow);
        if (focusNodeWindow) {
          if (this.tree.getTiledChildren(focusNodeWindow.parentNode.childNodes).length === 0) {
            this.tree.resetSiblingPercent(focusNodeWindow.parentNode.parentNode);
          }
          this.tree.resetSiblingPercent(focusNodeWindow.parentNode);
        }

        let prevFrozen = this._freezeRender;
        if (prevFrozen) this.unfreezeRender();
        this.renderTree("minimize");
        if (prevFrozen) this.freezeRender();
      }),
      shellWm.connect("unminimize", () => {
        let focusNodeWindow = this.tree.findNode(this.focusMetaWindow);
        if (focusNodeWindow) {
          this.tree.resetSiblingPercent(focusNodeWindow.parentNode);
        }

        let prevFrozen = this._freezeRender;
        if (prevFrozen) this.unfreezeRender();
        this.renderTree("unminimize");
        if (prevFrozen) this.freezeRender();
      }),
      shellWm.connect("show-tile-preview", (_, _metaWindow, _rect, _num) => {
        // Empty
      }),
    ];

    const globalWsm = global.workspace_manager;

    this._workspaceManagerSignals = [
      globalWsm.connect("showing-desktop-changed", () => {
        this.hideWindowBorders();
        this.updateDecorationLayout();
      }),
      globalWsm.connect("workspace-added", (_, wsIndex) => {
        this.tree.addWorkspace(wsIndex);
        this.trackCurrentMonWs();
        this.workspaceAdded = true;
        this.renderTree("workspace-added");
      }),
      globalWsm.connect("workspace-removed", (_, wsIndex) => {
        this.tree.removeWorkspace(wsIndex);
        this.trackCurrentMonWs();
        this.workspaceRemoved = true;
        this.updateDecorationLayout();
        this.renderTree("workspace-removed");
      }),
      globalWsm.connect("active-workspace-changed", () => {
        this.hideWindowBorders();
        this.trackCurrentMonWs();
        this.updateDecorationLayout();
        this.renderTree("active-workspace-changed");
      }),
    ];

    let numberOfWorkspaces = globalWsm.get_n_workspaces();

    for (let i = 0; i < numberOfWorkspaces; i++) {
      let workspace = globalWsm.get_workspace_by_index(i);
      this.bindWorkspaceSignals(workspace);
    }

    let settings = this.ext.settings;

    settings.connect("changed", (_, settingName) => {
      switch (settingName) {
        case "focus-border-toggle":
          this.renderTree(settingName);
          break;
        case "tiling-mode-enabled":
          this.renderTree(settingName);
          break;
        case "window-gap-size-increment":
        case "window-gap-size":
        case "window-gap-hidden-on-single":
        case "workspace-skip-tile":
          this.renderTree(settingName, true);
          break;
        case "stacked-tiling-mode-enabled":
          if (!settings.get_boolean(settingName)) {
            let stackedNodes = this.tree.getNodeByLayout(LAYOUT_TYPES.STACKED);
            stackedNodes.forEach((node) => {
              node.prevLayout = node.layout;
              node.layout = this.determineSplitLayout();
            });
          } else {
            let hSplitNodes = this.tree.getNodeByLayout(LAYOUT_TYPES.HSPLIT);
            let vSplitNodes = this.tree.getNodeByLayout(LAYOUT_TYPES.VSPLIT);
            Array.prototype.push.apply(hSplitNodes, vSplitNodes);
            hSplitNodes.forEach((node) => {
              if (node.prevLayout && node.prevLayout === LAYOUT_TYPES.STACKED) {
                node.layout = LAYOUT_TYPES.STACKED;
              }
            });
          }
          this.renderTree(settingName);
          break;
        case "tabbed-tiling-mode-enabled":
          if (!settings.get_boolean(settingName)) {
            let tabbedNodes = this.tree.getNodeByLayout(LAYOUT_TYPES.TABBED);
            tabbedNodes.forEach((node) => {
              node.prevLayout = node.layout;
              node.layout = this.determineSplitLayout();
            });
          } else {
            let hSplitNodes = this.tree.getNodeByLayout(LAYOUT_TYPES.HSPLIT);
            let vSplitNodes = this.tree.getNodeByLayout(LAYOUT_TYPES.VSPLIT);
            Array.prototype.push.apply(hSplitNodes, vSplitNodes);
            hSplitNodes.forEach((node) => {
              if (node.prevLayout && node.prevLayout === LAYOUT_TYPES.TABBED) {
                node.layout = LAYOUT_TYPES.TABBED;
              }
            });
          }
          this.renderTree(settingName);
          break;
        case "css-updated":
          this.theme.reloadStylesheet();
          break;
        case "float-always-on-top-enabled":
          if (!settings.get_boolean(settingName)) {
            this.cleanupAlwaysFloat();
          } else {
            this.restoreAlwaysFloat();
          }
          break;
        default:
          break;
      }
    });

    this._overviewSignals = [
      Main.overview.connect("hiding", () => {
        this.fromOverview = true;
        const eventObj = {
          name: "focus-after-overview",
          callback: () => {
            const focusNodeWindow = this.tree.findNode(this.focusMetaWindow);
            this.updateStackedFocus(focusNodeWindow);
            this.updateTabbedFocus(focusNodeWindow);
          },
        };
        this.queueEvent(eventObj);
      }),
      Main.overview.connect("showing", () => {
        this.toOverview = true;
      }),
    ];

    this._signalsBound = true;
  }

  cleanupAlwaysFloat() {
    // remove the setting for each node window
    this.allNodeWindows.forEach((w) => {
      if (w.mode === WINDOW_MODES.FLOAT) {
        w.nodeValue.is_above() && w.nodeValue.unmake_above();
      }
    });
  }

  restoreAlwaysFloat() {
    this.allNodeWindows.forEach((w) => {
      if (w.mode === WINDOW_MODES.FLOAT) {
        !w.nodeValue.is_above() && w.nodeValue.make_above();
      }
    });
  }

  trackCurrentMonWs() {
    let metaWindow = this.focusMetaWindow;
    if (!metaWindow) return;
    const currentMonitor = global.display.get_current_monitor();
    const currentWorkspace = global.display.get_workspace_manager().get_active_workspace_index();

    let currentMonWs = `mo${currentMonitor}ws${currentWorkspace}`;
    let activeMetaMonWs = `mo${metaWindow.get_monitor()}ws${metaWindow.get_workspace().index()}`;
    let currentWsNode = this.tree.findNode(`ws${currentWorkspace}`);

    if (!currentWsNode) {
      return;
    }

    // Search for all the valid windows on the workspace
    const monWindows = currentWsNode.getNodeByType(NODE_TYPES.WORKSPACE).flatMap((ws) => {
      return ws
        .getNodeByType(NODE_TYPES.WINDOW)
        .filter(
          (w) =>
            !w.nodeValue.minimized &&
            w.isTile() &&
            w.nodeValue !== metaWindow &&
            // The searched window should be on the same monitor workspace
            // This ensures that Forge already updated the workspace node tree:
            currentMonWs === activeMetaMonWs
        )
        .map((w) => w.nodeValue);
    });

    this.sortedWindows = global.display.sort_windows_by_stacking(monWindows).reverse();
  }

  // TODO move this to workspace.js
  bindWorkspaceSignals(metaWorkspace) {
    if (metaWorkspace) {
      if (!metaWorkspace.workspaceSignals) {
        let workspaceSignals = [
          metaWorkspace.connect("window-added", (_, metaWindow) => {
            if (!this._wsWindowAddSrcId) {
              this._wsWindowAddSrcId = GLib.timeout_add(GLib.PRIORITY_DEFAULT, 200, () => {
                this.updateMetaWorkspaceMonitor(
                  "window-added",
                  metaWindow.get_monitor(),
                  metaWindow
                );
                this._wsWindowAddSrcId = 0;
                return false;
              });
            }
          }),
        ];
        metaWorkspace.workspaceSignals = workspaceSignals;
      }
    }
  }

  // TODO move this in command.js
  command(action) {
    let focusWindow = this.focusMetaWindow;
    // Do not check if the node window is null, some of the commands do not need the focus window
    let focusNodeWindow = this.findNodeWindow(focusWindow);
    let currentLayout;

    switch (action.name) {
      case "FloatToggle":
      case "FloatClassToggle":
        this.toggleFloatingMode(action, focusWindow);

        const rectRequest = {
          x: action.x,
          y: action.y,
          width: action.width,
          height: action.height,
        };

        let moveRect = {
          x: Utils.resolveX(rectRequest, focusWindow),
          y: Utils.resolveY(rectRequest, focusWindow),
          width: Utils.resolveWidth(rectRequest, focusWindow),
          height: Utils.resolveHeight(rectRequest, focusWindow),
        };

        this.move(focusWindow, moveRect);

        let existParent = focusNodeWindow.parentNode;

        if (this.tree.getTiledChildren(existParent.childNodes).length <= 1) {
          existParent.percent = 0.0;
          this.tree.resetSiblingPercent(existParent.parentNode);
        }

        this.tree.resetSiblingPercent(existParent);
        this.renderTree("float-toggle", true);
        break;
      case "Move":
        this.unfreezeRender();
        let moveDirection = Utils.resolveDirection(action.direction);
        let prev = focusNodeWindow;
        let moved = this.tree.move(focusNodeWindow, moveDirection);
        if (!focusNodeWindow) {
          focusNodeWindow = this.findNodeWindow(this.focusMetaWindow);
        }
        this.queueEvent({
          name: "move",
          callback: () => {
            if (this.eventQueue.length <= 0) {
              this.unfreezeRender();
              if (focusNodeWindow.parentNode.layout === LAYOUT_TYPES.STACKED) {
                focusNodeWindow.parentNode.appendChild(focusNodeWindow);
                focusNodeWindow.nodeValue.raise();
                focusNodeWindow.nodeValue.activate(global.display.get_current_time());
                this.renderTree("move-stacked-queue");
              }
              if (focusNodeWindow.parentNode.layout === LAYOUT_TYPES.TABBED) {
                focusNodeWindow.nodeValue.raise();
                focusNodeWindow.nodeValue.activate(global.display.get_current_time());
                if (prev) prev.parentNode.lastTabFocus = prev.nodeValue;
                this.renderTree("move-tabbed-queue");
              }
            }
          },
        });
        if (moved) {
          if (prev) prev.parentNode.lastTabFocus = prev.nodeValue;
          this.renderTree("move-window");
        }

        break;
      case "Focus":
        let focusDirection = Utils.resolveDirection(action.direction);
        focusNodeWindow = this.tree.focus(focusNodeWindow, focusDirection);
        if (!focusNodeWindow) {
          focusNodeWindow = this.findNodeWindow(this.focusMetaWindow);
        }
        break;
      case "Swap":
        if (!focusNodeWindow) return;
        this.unfreezeRender();
        let swapDirection = Utils.resolveDirection(action.direction);
        this.tree.swap(focusNodeWindow, swapDirection);
        focusNodeWindow.nodeValue.raise();
        this.updateTabbedFocus(focusNodeWindow);
        this.updateStackedFocus(focusNodeWindow);
        this.renderTree("swap", true);
        break;
      case "Split":
        if (!focusNodeWindow) return;
        currentLayout = focusNodeWindow.parentNode.layout;
        if (currentLayout === LAYOUT_TYPES.STACKED || currentLayout === LAYOUT_TYPES.TABBED) {
          return;
        }
        let orientation = action.orientation
          ? action.orientation.toUpperCase()
          : ORIENTATION_TYPES.NONE;
        this.tree.split(focusNodeWindow, orientation);
        this.renderTree("split");
        break;
      case "LayoutToggle":
        if (!focusNodeWindow) return;
        currentLayout = focusNodeWindow.parentNode.layout;
        if (currentLayout === LAYOUT_TYPES.HSPLIT) {
          focusNodeWindow.parentNode.layout = LAYOUT_TYPES.VSPLIT;
        } else if (currentLayout === LAYOUT_TYPES.VSPLIT) {
          focusNodeWindow.parentNode.layout = LAYOUT_TYPES.HSPLIT;
        }
        this.tree.attachNode = focusNodeWindow.parentNode;
        this.renderTree("layout-split-toggle");
        break;
      case "FocusBorderToggle":
        let focusBorderEnabled = this.ext.settings.get_boolean("focus-border-toggle");
        this.ext.settings.set_boolean("focus-border-toggle", !focusBorderEnabled);
        break;
      case "TilingModeToggle":
        // FIXME, not sure if this toggle is still needed from a use case
        // perspective, since Extension.disable also should do the same thing.
        let tilingModeEnabled = this.ext.settings.get_boolean("tiling-mode-enabled");
        this.ext.settings.set_boolean("tiling-mode-enabled", !tilingModeEnabled);
        if (tilingModeEnabled) {
          this.floatAllWindows();
        } else {
          this.unfloatAllWindows();
        }
        this.renderTree(`tiling-mode-toggle ${!tilingModeEnabled}`);
        break;
      case "GapSize":
        let gapIncrement = this.ext.settings.get_uint("window-gap-size-increment");
        let amount = action.amount;
        gapIncrement = gapIncrement + amount;
        if (gapIncrement < 0) gapIncrement = 0;
        if (gapIncrement > 8) gapIncrement = 8;
        this.ext.settings.set_uint("window-gap-size-increment", gapIncrement);
        break;
      case "WorkspaceActiveTileToggle":
        let activeWorkspace = global.workspace_manager.get_active_workspace_index();
        let skippedWorkspaces = this.ext.settings.get_string("workspace-skip-tile");
        let workspaceSkipped = false;
        let skippedArr = [];
        if (skippedWorkspaces.length === 0) {
          skippedArr.push(`${activeWorkspace}`);
          this.floatWorkspace(activeWorkspace);
        } else {
          skippedArr = skippedWorkspaces.split(",");

          for (let i = 0; i < skippedArr.length; i++) {
            if (`${skippedArr[i]}` === `${activeWorkspace}`) {
              workspaceSkipped = true;
              break;
            }
          }

          if (workspaceSkipped) {
            // tile this workspace
            let indexWs = skippedArr.indexOf(`${activeWorkspace}`);
            skippedArr.splice(indexWs, 1);
            this.unfloatWorkspace(activeWorkspace);
          } else {
            // skip tiling workspace
            skippedArr.push(`${activeWorkspace}`);
            this.floatWorkspace(activeWorkspace);
          }
        }
        this.ext.settings.set_string("workspace-skip-tile", skippedArr.toString());
        this.renderTree("workspace-toggle");
        break;
      case "LayoutStackedToggle":
        if (!focusNodeWindow) return;
        if (!this.ext.settings.get_boolean("stacked-tiling-mode-enabled")) return;

        if (focusNodeWindow.parentNode.isMonitor()) {
          this.tree.split(focusNodeWindow, ORIENTATION_TYPES.HORIZONTAL, true);
        }

        currentLayout = focusNodeWindow.parentNode.layout;

        if (currentLayout === LAYOUT_TYPES.STACKED) {
          focusNodeWindow.parentNode.layout = this.determineSplitLayout();
          this.tree.resetSiblingPercent(focusNodeWindow.parentNode);
        } else {
          if (currentLayout === LAYOUT_TYPES.TABBED) {
            focusNodeWindow.parentNode.lastTabFocus = null;
          }
          focusNodeWindow.parentNode.layout = LAYOUT_TYPES.STACKED;
          let lastChild = focusNodeWindow.parentNode.lastChild;
          if (lastChild.nodeType === NODE_TYPES.WINDOW) {
            lastChild.nodeValue.activate(global.display.get_current_time());
          }
        }
        this.unfreezeRender();
        this.tree.attachNode = focusNodeWindow.parentNode;
        this.renderTree("layout-stacked-toggle");
        break;
      case "LayoutTabbedToggle":
        if (!focusNodeWindow) return;
        if (!this.ext.settings.get_boolean("tabbed-tiling-mode-enabled")) return;

        if (focusNodeWindow.parentNode.isMonitor()) {
          this.tree.split(focusNodeWindow, ORIENTATION_TYPES.HORIZONTAL, true);
        }

        currentLayout = focusNodeWindow.parentNode.layout;

        if (currentLayout === LAYOUT_TYPES.TABBED) {
          focusNodeWindow.parentNode.layout = this.determineSplitLayout();
          this.tree.resetSiblingPercent(focusNodeWindow.parentNode);
          focusNodeWindow.parentNode.lastTabFocus = null;
        } else {
          focusNodeWindow.parentNode.layout = LAYOUT_TYPES.TABBED;
          focusNodeWindow.parentNode.lastTabFocus = focusNodeWindow.nodeValue;
        }
        this.unfreezeRender();
        this.tree.attachNode = focusNodeWindow.parentNode;
        this.renderTree("layout-tabbed-toggle");
        break;
      case "CancelOperation":
        if (focusNodeWindow.mode === WINDOW_MODES.GRAB_TILE) {
          this.cancelGrab = true;
        }
        break;
      case "PrefsOpen":
        let existWindow = Utils.findWindowWith(this.prefsTitle);
        if (existWindow && existWindow.get_workspace()) {
          existWindow
            .get_workspace()
            .activate_with_focus(existWindow, global.display.get_current_time());
          this.moveCenter(existWindow);
        } else {
          this.ext.openPreferences();
        }
        break;
      case "WindowSwapLastActive":
        if (focusNodeWindow) {
          let lastActiveWindow = global.display.get_tab_next(
            Meta.TabList.NORMAL,
            global.display.get_workspace_manager().get_active_workspace(),
            focusNodeWindow.nodeValue,
            false
          );
          let lastActiveNodeWindow = this.tree.findNode(lastActiveWindow);
          this.tree.swapPairs(lastActiveNodeWindow, focusNodeWindow);
          this.renderTree("swap-last-active");
        }
        break;
      case "SnapLayoutMove":
        if (focusNodeWindow) {
          let workareaRect = focusNodeWindow.nodeValue.get_work_area_current_monitor();
          let layoutAmount = action.amount;
          let layoutDirection = action.direction.toUpperCase();
          let layout = {};
          let processGap = false;

          switch (layoutDirection) {
            case "LEFT":
              layout.width = layoutAmount * workareaRect.width;
              layout.height = workareaRect.height;
              layout.x = workareaRect.x;
              layout.y = workareaRect.y;
              processGap = true;
              break;
            case "RIGHT":
              layout.width = layoutAmount * workareaRect.width;
              layout.height = workareaRect.height;
              layout.x = workareaRect.x + (workareaRect.width - layout.width);
              layout.y = workareaRect.y;
              processGap = true;
              break;
            case "CENTER":
              let metaRect = this.focusMetaWindow.get_frame_rect();
              layout.x = "center";
              layout.y = "center";
              layout = {
                x: Utils.resolveX(layout, this.focusMetaWindow),
                y: Utils.resolveY(layout, this.focusMetaWindow),
                width: metaRect.width,
                height: metaRect.height,
              };
              break;
            default:
              break;
          }
          focusNodeWindow.rect = layout;
          if (processGap) {
            focusNodeWindow.rect = this.tree.processGap(focusNodeWindow);
          }
          if (!focusNodeWindow.isFloat()) {
            this.addFloatOverride(focusNodeWindow.nodeValue, false);
          }
          this.move(focusNodeWindow.nodeValue, focusNodeWindow.rect);
          this.queueEvent({
            name: "snap-layout-move",
            callback: () => {
              this.renderTree("snap-layout-move");
            },
          });
          break;
        }

      case "ShowTabDecorationToggle":
        if (!focusNodeWindow) return;
        if (!this.ext.settings.get_boolean("tabbed-tiling-mode-enabled")) return;

        let showTabs = this.ext.settings.get_boolean("showtab-decoration-enabled");
        this.ext.settings.set_boolean("showtab-decoration-enabled", !showTabs);

        this.unfreezeRender();
        this.tree.attachNode = focusNodeWindow.parentNode;
        this.renderTree("showtab-decoration-enabled");
        break;

      case "WindowResizeRight":
        this.resize(Meta.GrabOp.KEYBOARD_RESIZING_E, action.amount);
        break;

      case "WindowResizeLeft":
        this.resize(Meta.GrabOp.KEYBOARD_RESIZING_W, action.amount);
        break;

      case "WindowResizeTop":
        this.resize(Meta.GrabOp.KEYBOARD_RESIZING_N, action.amount);
        break;

      case "WindowResizeBottom":
        this.resize(Meta.GrabOp.KEYBOARD_RESIZING_S, action.amount);
        break;

      default:
        break;
    }
  }

  resize(grabOp, amount) {
    let metaWindow = this.focusMetaWindow;
    let display = global.display;

    this._handleGrabOpBegin(display, metaWindow, grabOp);

    let rect = metaWindow.get_frame_rect();
    let direction = Utils.directionFromGrab(grabOp);

    switch (direction) {
      case Meta.MotionDirection.RIGHT:
        rect.width = rect.width + amount;
        break;
      case Meta.MotionDirection.LEFT:
        rect.width = rect.width + amount;
        rect.x = rect.x - amount;
        break;
      case Meta.MotionDirection.UP:
        rect.height = rect.height + amount;
        break;
      case Meta.MotionDirection.DOWN:
        rect.height = rect.height + amount;
        rect.y = rect.y - amount;
        break;
    }
    this.move(metaWindow, rect);
    this.queueEvent(
      {
        name: "manual-resize",
        callback: () => {
          if (this.eventQueue.length === 0) {
            this._handleGrabOpEnd(display, metaWindow, grabOp);
          }
        },
      },
      50
    );
  }

  disable() {
    Utils._disableDecorations();
    this._removeSignals();
    this.disabled = true;
    Logger.debug(`extension:disable`);
  }

  enable() {
    this._bindSignals();
    this.reloadTree("enable");
    Logger.debug(`extension:enable`);
  }

  findNodeWindow(metaWindow) {
    return this.tree.findNode(metaWindow);
  }

  get focusMetaWindow() {
    return global.display.get_focus_window();
  }

  get tree() {
    if (!this._tree) {
      this._tree = new Tree(this);
    }
    return this._tree;
  }

  get kbd() {
    if (!this._kbd) {
      this._kbd = new Keybindings(this.ext);
      this.ext.keybindings = this._kbd;
    }

    return this._kbd;
  }

  get windowsActiveWorkspace() {
    let wsManager = global.workspace_manager;
    return global.display.get_tab_list(Meta.TabList.NORMAL_ALL, wsManager.get_active_workspace());
  }

  get windowsAllWorkspaces() {
    let wsManager = global.workspace_manager;
    let windowsAll = [];

    for (let i = 0; i < wsManager.get_n_workspaces(); i++) {
      Array.prototype.push.apply(
        windowsAll,
        global.display.get_tab_list(Meta.TabList.NORMAL_ALL, wsManager.get_workspace_by_index(i))
      );
    }
    windowsAll.sort((w1, w2) => {
      return w1.get_stable_sequence() - w2.get_stable_sequence();
    });
    return windowsAll;
  }

  getWindowsOnWorkspace(workspaceIndex) {
    const workspaceNode = this.tree.findNode(`ws${workspaceIndex}`);
    const workspaceWindows = workspaceNode.getNodeByType(NODE_TYPES.WINDOW);
    return workspaceWindows;
  }

  determineSplitLayout() {
    // if the monitor width is less than height, the monitor could be vertical orientation;
    let monitorRect = global.display.get_monitor_geometry(global.display.get_current_monitor());
    if (monitorRect.width < monitorRect.height) {
      return LAYOUT_TYPES.VSPLIT;
    }
    return LAYOUT_TYPES.HSPLIT;
  }

  floatWorkspace(workspaceIndex) {
    const workspaceWindows = this.getWindowsOnWorkspace(workspaceIndex);
    if (!workspaceWindows) return;
    workspaceWindows.forEach((w) => {
      w.float = true;
    });
  }

  unfloatWorkspace(workspaceIndex) {
    const workspaceWindows = this.getWindowsOnWorkspace(workspaceIndex);
    if (!workspaceWindows) return;
    workspaceWindows.forEach((w) => {
      w.tile = true;
    });
  }

  hideWindowBorders() {
    this.tree.nodeWindows.forEach((nodeWindow) => {
      let actor = nodeWindow.windowActor;
      if (actor) {
        if (actor.border) {
          actor.border.hide();
        }
        if (actor.splitBorder) {
          actor.splitBorder.hide();
        }
      }
      if (nodeWindow.parentNode.isTabbed()) {
        if (nodeWindow.tab) {
          // TODO: review the cleanup of the tab:St.Widget variable
          try {
            nodeWindow.tab.remove_style_class_name("window-tabbed-tab-active");
          } catch (e) {
            Logger.warn(e);
          }
        }
      }
    });
  }

  // Window movement API
  move(metaWindow, rect) {
    if (!metaWindow) return;
    if (metaWindow.grabbed) return;
    metaWindow.unmaximize(Meta.MaximizeFlags.HORIZONTAL);
    metaWindow.unmaximize(Meta.MaximizeFlags.VERTICAL);
    metaWindow.unmaximize(Meta.MaximizeFlags.BOTH);

    let windowActor = metaWindow.get_compositor_private();
    if (!windowActor) return;
    windowActor.remove_all_transitions();

    metaWindow.move_frame(true, rect.x, rect.y);
    metaWindow.move_resize_frame(true, rect.x, rect.y, rect.width, rect.height);
  }

  moveCenter(metaWindow) {
    if (!metaWindow) return;
    let frameRect = metaWindow.get_frame_rect();
    const rectRequest = {
      x: "center",
      y: "center",
      width: frameRect.width,
      height: frameRect.height,
    };

    let moveRect = {
      x: Utils.resolveX(rectRequest, metaWindow),
      y: Utils.resolveY(rectRequest, metaWindow),
      width: Utils.resolveWidth(rectRequest, metaWindow),
      height: Utils.resolveHeight(rectRequest, metaWindow),
    };
    this.move(metaWindow, moveRect);
  }

  rectForMonitor(node, targetMonitor) {
    if (!node || (node && node.nodeType !== NODE_TYPES.WINDOW)) return null;
    if (targetMonitor < 0) return null;
    let currentWorkArea = node.nodeValue.get_work_area_current_monitor();
    let nextWorkArea = node.nodeValue.get_work_area_for_monitor(targetMonitor);

    if (currentWorkArea && nextWorkArea) {
      let rect = node.rect;
      if (!rect && node.mode === WINDOW_MODES.FLOAT) {
        rect = node.nodeValue.get_frame_rect();
      }
      let hRatio = 1;
      let wRatio = 1;

      hRatio = nextWorkArea.height / currentWorkArea.height;
      wRatio = nextWorkArea.width / currentWorkArea.width;
      rect.height *= hRatio;
      rect.width *= wRatio;

      if (nextWorkArea.y < currentWorkArea.y) {
        rect.y =
          ((nextWorkArea.y + rect.y - currentWorkArea.y) / currentWorkArea.height) *
          nextWorkArea.height;
      } else if (nextWorkArea.y > currentWorkArea.y) {
        rect.y = (rect.y / currentWorkArea.height) * nextWorkArea.height + nextWorkArea.y;
      }

      if (nextWorkArea.x < currentWorkArea.x) {
        rect.x =
          ((nextWorkArea.x + rect.x - currentWorkArea.x) / currentWorkArea.width) *
          nextWorkArea.width;
      } else if (nextWorkArea.x > currentWorkArea.x) {
        rect.x = (rect.x / currentWorkArea.width) * nextWorkArea.width + nextWorkArea.x;
      }
      return rect;
    }
    return null;
  }

  _removeSignals() {
    if (!this._signalsBound) return;

    if (this._displaySignals) {
      for (const displaySignal of this._displaySignals) {
        global.display.disconnect(displaySignal);
      }
      this._displaySignals.length = 0;
      this._displaySignals = undefined;
    }

    if (this._windowManagerSignals) {
      for (const windowManagerSignal of this._windowManagerSignals) {
        global.window_manager.disconnect(windowManagerSignal);
      }
      this._windowManagerSignals.length = 0;
      this._windowManagerSignals = undefined;
    }

    const globalWsm = global.workspace_manager;

    if (this._workspaceManagerSignals) {
      for (const workspaceManagerSignal of this._workspaceManagerSignals) {
        globalWsm.disconnect(workspaceManagerSignal);
      }
      this._workspaceManagerSignals.length = 0;
      this._workspaceManagerSignals = undefined;
    }

    let numberOfWorkspaces = globalWsm.get_n_workspaces();

    for (let i = 0; i < numberOfWorkspaces; i++) {
      let workspace = globalWsm.get_workspace_by_index(i);
      if (workspace.workspaceSignals) {
        for (const workspaceSignal of workspace.workspaceSignals) {
          workspace.disconnect(workspaceSignal);
        }
        workspace.workspaceSignals.length = 0;
        workspace.workspaceSignals = undefined;
      }
    }

    let allWindows = this.windowsAllWorkspaces;

    if (allWindows) {
      for (let metaWindow of allWindows) {
        if (metaWindow.windowSignals !== undefined) {
          for (const windowSignal of metaWindow.windowSignals) {
            metaWindow.disconnect(windowSignal);
          }
          metaWindow.windowSignals.length = 0;
          metaWindow.windowSignals = undefined;
        }

        let windowActor = metaWindow.get_compositor_private();
        if (windowActor && windowActor.actorSignals) {
          for (const actorSignal of windowActor.actorSignals) {
            windowActor.disconnect(actorSignal);
          }
          windowActor.actorSignals.length = 0;
          windowActor.actorSignals = undefined;
        }

        if (windowActor && windowActor.border) {
          windowActor.border.hide();
          if (global.window_group) {
            global.window_group.remove_child(windowActor.border);
          }
          windowActor.border = undefined;
        }

        if (windowActor && windowActor.splitBorder) {
          windowActor.splitBorder.hide();
          if (global.window_group) {
            global.window_group.remove_child(windowActor.splitBorder);
          }
          windowActor.splitBorder = undefined;
        }
      }
    }

    if (this._renderTreeSrcId) {
      GLib.Source.remove(this._renderTreeSrcId);
      this._renderTreeSrcId = 0;
    }

    if (this._reloadTreeSrcId) {
      GLib.Source.remove(this._reloadTreeSrcId);
      this._reloadTreeSrcId = 0;
    }

    if (this._wsWindowAddSrcId) {
      GLib.Source.remove(this._wsWindowAddSrcId);
      this._wsWindowAddSrcId = 0;
    }

    if (this._queueSourceId) {
      GLib.Source.remove(this._queueSourceId);
      this._queueSourceId = 0;
    }

    if (this._prefsOpenSrcId) {
      GLib.Source.remove(this._prefsOpenSrcId);
      this._prefsOpenSrcId = 0;
    }

    if (this._overviewSignals) {
      for (const overviewSignal of this._overviewSignals) {
        Main.overview.disconnect(overviewSignal);
      }
      this._overviewSignals.length = 0;
      this._overviewSignals = null;
    }

    this._signalsBound = false;
  }

  renderTree(from, force = false) {
    let wasFrozen = this._freezeRender;
    if (force && wasFrozen) this.unfreezeRender();
    if (this._freezeRender || !this.ext.settings.get_boolean("tiling-mode-enabled")) {
      this.updateDecorationLayout();
      this.updateBorderLayout();
    } else {
      if (!this._renderTreeSrcId) {
        this._renderTreeSrcId = GLib.idle_add(GLib.PRIORITY_DEFAULT, () => {
          this.processFloats();
          this.tree.render(from);
          this._renderTreeSrcId = 0;
          this.updateDecorationLayout();
          this.updateBorderLayout();
          if (wasFrozen) this.freezeRender();
          return false;
        });
      }
    }
  }

  processFloats() {
    this.allNodeWindows.forEach((nodeWindow) => {
      let metaWindow = nodeWindow.nodeValue;
      if (this.isFloatingExempt(metaWindow) || !this.isActiveWindowWorkspaceTiled(metaWindow)) {
        nodeWindow.float = true;
      } else {
        nodeWindow.float = false;
      }
    });
  }

  get allNodeWindows() {
    return this.tree.getNodeByType(NODE_TYPES.WINDOW);
  }

  /**
   * Reloads the tree. This is an expensive operation.
   * Useful when using dynamic workspaces in GNOME-shell.
   *
   * TODO: add support to reload the tree from a JSON dump file.
   * TODO: move this to tree.js
   */
  reloadTree(from) {
    if (!this._reloadTreeSrcId) {
      this._reloadTreeSrcId = GLib.idle_add(GLib.PRIORITY_LOW, () => {
        Utils._disableDecorations();
        let treeWorkspaces = this.tree.nodeWorkpaces;
        let wsManager = global.workspace_manager;
        let globalWsNum = wsManager.get_n_workspaces();
        // empty out the root children nodes
        this.tree.childNodes.length = 0;
        this.tree.attachNode = undefined;
        // initialize the workspaces and monitors id strings
        this.tree._initWorkspaces();
        this.trackCurrentWindows();
        this.renderTree(from);
        this._reloadTreeSrcId = 0;
        return false;
      });
    }
  }

  sameParentMonitor(firstNode, secondNode) {
    if (!firstNode || !secondNode) return false;
    if (!firstNode.nodeValue || !secondNode.nodeValue) return false;
    if (!firstNode.nodeValue.get_workspace()) return false;
    if (!secondNode.nodeValue.get_workspace()) return false;
    let firstMonWs = `mo${firstNode.nodeValue.get_monitor()}ws${firstNode.nodeValue
      .get_workspace()
      .index()}`;
    let secondMonWs = `mo${secondNode.nodeValue.get_monitor()}ws${secondNode.nodeValue
      .get_workspace()
      .index()}`;
    return firstMonWs === secondMonWs;
  }

  showWindowBorders() {
    let metaWindow = this.focusMetaWindow;
    if (!metaWindow) return;
    let windowActor = metaWindow.get_compositor_private();
    if (!windowActor) return;
    let nodeWindow = this.findNodeWindow(metaWindow);
    if (!nodeWindow) return;
    if (metaWindow.get_wm_class() === null) return;

    let borders = [];
    let focusBorderEnabled = this.ext.settings.get_boolean("focus-border-toggle");
    let splitBorderEnabled = this.ext.settings.get_boolean("split-border-toggle");
    let tilingModeEnabled = this.ext.settings.get_boolean("tiling-mode-enabled");
    let gap = this.calculateGaps(nodeWindow);
    let maximized = () => {
      return metaWindow.get_maximized() === 3 || metaWindow.is_fullscreen() || gap === 0;
    };
    let monitorCount = global.display.get_n_monitors();
    let tiledChildren = this.tree.getTiledChildren(nodeWindow.parentNode.childNodes);
    let inset = 3;
    let parentNode = nodeWindow.parentNode;

    const floatingWindow = nodeWindow.isFloat();
    const tiledBorder = windowActor.border;

    if (parentNode.isTabbed()) {
      if (nodeWindow.tab) {
        nodeWindow.tab.add_style_class_name("window-tabbed-tab-active");
      }
    }

    if (tiledBorder && focusBorderEnabled) {
      if (
        !maximized() ||
        (gap === 0 && tiledChildren.length === 1 && monitorCount > 1) ||
        (gap === 0 && tiledChildren.length > 1)
      ) {
        if (tilingModeEnabled) {
          if (parentNode.isStacked()) {
            if (!floatingWindow) {
              tiledBorder.set_style_class_name("window-stacked-border");
            } else {
              tiledBorder.set_style_class_name("window-floated-border");
            }
          } else if (parentNode.isTabbed()) {
            if (!floatingWindow) {
              tiledBorder.set_style_class_name("window-tabbed-border");
              if (nodeWindow.backgroundTab) {
                tiledBorder.add_style_class_name("window-tabbed-bg");
              }
            } else {
              tiledBorder.set_style_class_name("window-floated-border");
            }
          } else {
            if (!floatingWindow) {
              tiledBorder.set_style_class_name("window-tiled-border");
            } else {
              tiledBorder.set_style_class_name("window-floated-border");
            }
          }
        } else {
          tiledBorder.set_style_class_name("window-floated-border");
        }
        borders.push(tiledBorder);
      }
    }

    if (gap === 0 || metaWindow.get_maximized() === 1 || metaWindow.get_maximized() === 2) {
      inset = 0;
    }

    // handle the split border
    // It should only show when V or H-Split and with single child CONs
    if (
      splitBorderEnabled &&
      focusBorderEnabled &&
      tilingModeEnabled &&
      !nodeWindow.isFloat() &&
      !maximized &&
      parentNode.childNodes.length === 1 &&
      (parentNode.isCon() || parentNode.isMonitor()) &&
      !(parentNode.isTabbed() || parentNode.isStacked())
    ) {
      if (!windowActor.splitBorder) {
        let splitBorder = new St.Bin({ style_class: "window-split-border" });
        global.window_group.add_child(splitBorder);
        windowActor.splitBorder = splitBorder;
      }

      let splitBorder = windowActor.splitBorder;
      splitBorder.remove_style_class_name("window-split-vertical");
      splitBorder.remove_style_class_name("window-split-horizontal");

      if (parentNode.isVSplit()) {
        splitBorder.add_style_class_name("window-split-vertical");
      } else if (parentNode.isHSplit()) {
        splitBorder.add_style_class_name("window-split-horizontal");
      }
      borders.push(splitBorder);
    }

    let rect = metaWindow.get_frame_rect();

    borders.forEach((border) => {
      border.set_size(rect.width + inset * 2, rect.height + inset * 2);
      border.set_position(rect.x - inset, rect.y - inset);
      if (metaWindow.appears_focused && !metaWindow.minimized) {
        border.show();
      }
      if (global.window_group && global.window_group.contains(border)) {
        // TODO - sort the borders with split border being on top
        global.window_group.remove_child(border);
        // Add the border just above the focused window
        global.window_group.insert_child_above(border, metaWindow.get_compositor_private());
      }
    });
  }

  updateBorderLayout() {
    this.hideWindowBorders();
    this.showWindowBorders();
  }

  calculateGaps(node) {
    if (!node) return 0;

    let settings = this.ext.settings;
    let gapSize = settings.get_uint("window-gap-size");
    let gapIncrement = settings.get_uint("window-gap-size-increment");
    let gap = gapSize * gapIncrement;

    if (!node.isRoot()) {
      let hideGapWhenSingle = settings.get_boolean("window-gap-hidden-on-single");
      let parentNode = this.tree.findParent(node, NODE_TYPES.MONITOR);
      if (parentNode) {
        let tiled = parentNode
          .getNodeByMode(WINDOW_MODES.TILE)
          .filter((t) => t.isWindow() && !t.nodeValue.minimized);
        if (tiled.length == 1 && hideGapWhenSingle) gap = 0;
      }
    }

    return gap;
  }

  /**
   * Track meta/mutter windows and append them to the tree.
   * Windows can be attached on any of the following Node Types:
   * MONITOR, CONTAINER
   *
   */
  trackWindow(_display, metaWindow) {
    let autoSplit = this.ext.settings.get_boolean("auto-split-enabled");
    if (autoSplit && this.focusMetaWindow) {
      let currentFocusNode = this.tree.findNode(this.focusMetaWindow);
      if (currentFocusNode) {
        let currentParentFocusNode = currentFocusNode.parentNode;
        let layout = currentParentFocusNode.layout;
        if (layout === LAYOUT_TYPES.HSPLIT || layout === LAYOUT_TYPES.VSPLIT) {
          let frameRect = this.focusMetaWindow.get_frame_rect();
          let splitHorizontal = frameRect.width > frameRect.height;
          let orientation = splitHorizontal ? "horizontal" : "vertical";
          this.command({ name: "Split", orientation: orientation });
        }
      }
    }
    // Make window types configurable
    if (this._validWindow(metaWindow)) {
      let existNodeWindow = this.tree.findNode(metaWindow);
      Logger.debug(`Meta Window ${metaWindow.get_title()} ${metaWindow.get_window_type()}`);
      if (!existNodeWindow) {
        let attachTarget;

        const activeMonitor = global.display.get_current_monitor();
        const activeWorkspace = global.display.get_workspace_manager().get_active_workspace_index();
        let metaMonWs = `mo${activeMonitor}ws${activeWorkspace}`;

        // Check if the active monitor / workspace has windows
        let metaMonWsNode = this.tree.findNode(metaMonWs);
        if (!metaMonWsNode) {
          // Reload the tree as a last resort
          this.reloadTree("no-meta-monws");
          return;
        }

        let windowNodes = metaMonWsNode.getNodeByType(NODE_TYPES.WINDOW);
        let hasWindows = windowNodes.length > 0;

        attachTarget = this.tree.attachNode;
        attachTarget = attachTarget ? this.tree.findNode(attachTarget.nodeValue) : null;

        if (!attachTarget) {
          attachTarget = metaMonWsNode;
        } else {
          if (hasWindows) {
            if (attachTarget && metaMonWsNode.contains(attachTarget)) {
              // Use the attach target
            } else {
              // Find the first window
              attachTarget = windowNodes[0];
            }
          } else {
            attachTarget = metaMonWsNode;
          }
        }

        let nodeWindow = this.tree.createNode(
          attachTarget.nodeValue,
          NODE_TYPES.WINDOW,
          metaWindow,
          WINDOW_MODES.FLOAT
        );

        metaWindow.firstRender = true;

        let windowActor = metaWindow.get_compositor_private();

        if (!metaWindow.windowSignals) {
          let windowSignals = [
            metaWindow.connect("position-changed", (_metaWindow) => {
              let from = "position-changed";
              this.updateMetaPositionSize(_metaWindow, from);
            }),
            metaWindow.connect("size-changed", (_metaWindow) => {
              let from = "size-changed";
              this.updateMetaPositionSize(_metaWindow, from);
            }),
            metaWindow.connect("focus", (_metaWindowFocus) => {
              this.queueEvent({
                name: "focus-update",
                callback: () => {
                  this.unfreezeRender();
                  this.updateBorderLayout();
                  this.updateDecorationLayout();
                  this.updateStackedFocus();
                  this.updateTabbedFocus();
                },
              });
              let focusNodeWindow = this.tree.findNode(this.focusMetaWindow);
              if (focusNodeWindow) {
                // handle the attach node
                this.tree.attachNode = focusNodeWindow._parent;
                if (this.floatingWindow(focusNodeWindow)) {
                  this.queueEvent({
                    name: "raise-float",
                    callback: () => {
                      this.renderTree("raise-float-queue");
                    },
                  });
                }
                this.tree.attachNode = focusNodeWindow;
              }
              this.renderTree("focus", true);
            }),
            metaWindow.connect("workspace-changed", (_metaWindow) => {
              this.updateMetaWorkspaceMonitor("metawindow-workspace-changed", null, _metaWindow);
              this.trackCurrentMonWs();
            }),
          ];
          metaWindow.windowSignals = windowSignals;
        }

        if (!windowActor.actorSignals) {
          let actorSignals = [windowActor.connect("destroy", this.windowDestroy.bind(this))];
          windowActor.actorSignals = actorSignals;
        }

        if (!windowActor.border) {
          let border = new St.Bin({ style_class: "window-tiled-border" });

          if (global.window_group) global.window_group.add_child(border);

          windowActor.border = border;
          border.show();
        }

        this.postProcessWindow(nodeWindow);
        this.queueEvent(
          {
            name: "window-create-queue",
            callback: () => {
              metaWindow.unmaximize(Meta.MaximizeFlags.HORIZONTAL);
              metaWindow.unmaximize(Meta.MaximizeFlags.VERTICAL);
              metaWindow.unmaximize(Meta.MaximizeFlags.BOTH);
              this.renderTree("window-create", true);
            },
          },
          200
        );

        let childNodes = this.tree.getTiledChildren(nodeWindow.parentNode.childNodes);
        childNodes.forEach((n) => {
          n.percent = 0.0;
        });
      }
    }
  }

  postProcessWindow(nodeWindow) {
    let metaWindow = nodeWindow.nodeValue;
    if (metaWindow) {
      if (metaWindow.get_title() === this.prefsTitle) {
        metaWindow
          .get_workspace()
          .activate_with_focus(metaWindow, global.display.get_current_time());
        this.moveCenter(metaWindow);
      }
    }
  }

  updateStackedFocus(focusNodeWindow) {
    if (!focusNodeWindow) return;
    const parentNode = focusNodeWindow.parentNode;
    if (parentNode.layout === LAYOUT_TYPES.STACKED && !this._freezeRender) {
      parentNode.appendChild(focusNodeWindow);
      parentNode.childNodes
        .filter((child) => child.isWindow())
        .forEach((child) => child.nodeValue.raise());
      this.queueEvent({
        name: "render-focus-stack",
        callback: () => {
          this.renderTree("focus-stacked");
        },
      });
    }
  }

  updateTabbedFocus(focusNodeWindow) {
    if (!focusNodeWindow) return;
    if (focusNodeWindow.parentNode.layout === LAYOUT_TYPES.TABBED && !this._freezeRender) {
      const metaWindow = focusNodeWindow.nodeValue;
      metaWindow.raise();
    }
  }

  /**
   * Check if a Meta Window's workspace is skipped for tiling.
   */
  isActiveWindowWorkspaceTiled(metaWindow) {
    if (!metaWindow) return true;
    let skipWs = this.ext.settings.get_string("workspace-skip-tile");
    let skipArr = skipWs.split(",");
    let skipThisWs = false;

    for (let i = 0; i < skipArr.length; i++) {
      let activeWorkspaceForWin = metaWindow.get_workspace();
      if (activeWorkspaceForWin) {
        let wsIndex = activeWorkspaceForWin.index();
        if (skipArr[i].trim() === `${wsIndex}`) {
          skipThisWs = true;
          break;
        }
      }
    }
    return !skipThisWs;
  }

  /**
   * Check the current active workspace's tiling mode
   */
  isCurrentWorkspaceTiled() {
    let skipWs = this.ext.settings.get_string("workspace-skip-tile");
    let skipArr = skipWs.split(",");
    let skipThisWs = false;
    let wsMgr = global.workspace_manager;
    let wsIndex = wsMgr.get_active_workspace_index();

    for (let i = 0; i < skipArr.length; i++) {
      if (skipArr[i].trim() === `${wsIndex}`) {
        skipThisWs = true;
        break;
      }
    }
    return !skipThisWs;
  }

  trackCurrentWindows() {
    this.tree.attachNode = null;
    let windowsAll = this.windowsAllWorkspaces;
    for (let i = 0; i < windowsAll.length; i++) {
      let metaWindow = windowsAll[i];
      this.trackWindow(global.display, metaWindow);
      // This updates and handles dynamic workspaces
      this.updateMetaWorkspaceMonitor(
        "track-current-windows",
        metaWindow.get_monitor(),
        metaWindow
      );
    }
    this.updateDecorationLayout();
  }

  _validWindow(metaWindow) {
    let windowType = metaWindow.get_window_type();
    return (
      windowType === Meta.WindowType.NORMAL ||
      windowType === Meta.WindowType.MODAL_DIALOG ||
      windowType === Meta.WindowType.DIALOG
    );
  }

  windowDestroy(actor) {
    // Release any resources on the window
    let border = actor.border;
    if (border) {
      if (global.window_group) {
        global.window_group.remove_child(border);
        border.hide();
        border = null;
      }
    }

    let splitBorder = actor.splitBorder;
    if (splitBorder) {
      if (global.window_group) {
        global.window_group.remove_child(splitBorder);
        splitBorder.hide();
        splitBorder = null;
      }
    }

    let nodeWindow;
    nodeWindow = this.tree.findNodeByActor(actor);

    if (nodeWindow) {
      this.tree.removeNode(nodeWindow);
      this.renderTree("window-destroy-quick", true);
    }

    // find the next attachNode here
    let focusNodeWindow = this.tree.findNode(this.focusMetaWindow);
    if (focusNodeWindow) {
      this.tree.attachNode = focusNodeWindow.parentNode;
    }

    this.queueEvent({
      name: "window-destroy",
      callback: () => {
        this.renderTree("window-destroy", true);
      },
    });
  }

  /**
   * Handles any workspace/monitor update for the Meta.Window.
   */
  updateMetaWorkspaceMonitor(from, _monitor, metaWindow) {
    if (this._validWindow(metaWindow)) {
      if (metaWindow.get_workspace() === null) return;
      let existNodeWindow = this.tree.findNode(metaWindow);
      let metaMonWs = `mo${metaWindow.get_monitor()}ws${metaWindow.get_workspace().index()}`;
      let metaMonWsNode = this.tree.findNode(metaMonWs);
      if (existNodeWindow) {
        if (existNodeWindow.parentNode && metaMonWsNode) {
          // Uses the existing workspace, monitor that the metaWindow
          // belongs to.
          let containsWindow = metaMonWsNode.contains(existNodeWindow);
          if (!containsWindow) {
            // handle cleanup of resize percentages
            let existParent = existNodeWindow.parentNode;
            this.tree.resetSiblingPercent(existParent);
            metaMonWsNode.appendChild(existNodeWindow);

            // Ensure that the workspace tiling is honored
            if (this.isActiveWindowWorkspaceTiled(metaWindow)) {
              if (!this.grabOp === Meta.GrabOp.WINDOW_BASE) this.updateTabbedFocus(existNodeWindow);
              this.updateStackedFocus(existNodeWindow);
            } else {
              if (this.floatingWindow(existNodeWindow)) {
                existNodeWindow.nodeValue.raise();
              }
            }
          }
        }
      }
      this.renderTree(from);
    }
  }

  /**
   * Handle any updates to the current focused window's position.
   * Useful for updating the active window border, etc.
   */
  updateMetaPositionSize(_metaWindow, from) {
    let focusMetaWindow = this.focusMetaWindow;
    if (!focusMetaWindow) return;

    let focusNodeWindow = this.findNodeWindow(focusMetaWindow);
    if (!focusNodeWindow) return;

    let tilingModeEnabled = this.ext.settings.get_boolean("tiling-mode-enabled");

    if (focusNodeWindow.grabMode && tilingModeEnabled) {
      if (focusNodeWindow.grabMode === GRAB_TYPES.RESIZING) {
        this._handleResizing(focusNodeWindow);
      } else if (focusNodeWindow.grabMode === GRAB_TYPES.MOVING) {
        this._handleMoving(focusNodeWindow);
      }
    } else {
      if (focusMetaWindow.get_maximized() === 0) {
        this.renderTree(from);
      }
    }
    this.updateBorderLayout();
    this.updateDecorationLayout();
  }

  updateDecorationLayout() {
    if (this._freezeRender) return;
    let activeWsNode = this.currentWsNode;
    let allCons = this.tree.getNodeByType(NODE_TYPES.CON);

    // First, hide all decorations:
    allCons.forEach((con) => {
      if (con.decoration) {
        con.decoration.hide();
      }
    });

    // Next, handle showing-desktop usually by Super + D
    if (!activeWsNode) return;
    let allWindows = activeWsNode.getNodeByType(NODE_TYPES.WINDOW);
    let allHiddenWindows = allWindows.filter((w) => {
      let metaWindow = w.nodeValue;
      return !metaWindow.showing_on_its_workspace() || metaWindow.minimized;
    });

    // Then if all hidden, do not proceed showing the decorations at all;
    if (allWindows.length === allHiddenWindows.length) return;

    // Show the decoration where on all monitors of active workspace
    // But not on the monitor where there is a maximized or fullscreen window
    // Note, that when multi-display, user can have multi maximized windows,
    // So it needs to be fully filtered:
    let monWsNoMaxWindows = activeWsNode.getNodeByType(NODE_TYPES.MONITOR).filter((monitor) => {
      return (
        monitor.getNodeByType(NODE_TYPES.WINDOW).filter((w) => {
          return (
            w.nodeValue.get_maximized() === Meta.MaximizeFlags.BOTH || w.nodeValue.is_fullscreen()
          );
        }).length === 0
      );
    });

    monWsNoMaxWindows.forEach((monitorWs) => {
      let activeMonWsCons = monitorWs.getNodeByType(NODE_TYPES.CON);
      activeMonWsCons.forEach((con) => {
        let tiled = this.tree.getTiledChildren(con.childNodes);
        let showTabs = this.ext.settings.get_boolean("showtab-decoration-enabled");
        if (con.decoration && tiled.length > 0 && showTabs) {
          con.decoration.show();
          if (global.window_group.contains(con.decoration) && this.focusMetaWindow) {
            global.window_group.remove_child(con.decoration);
            // Show it below the focused window
            global.window_group.insert_child_below(
              con.decoration,
              this.focusMetaWindow.get_compositor_private()
            );
          }
          con.childNodes.forEach((cn) => {
            cn.render();
          });
        }
      });
    });
  }

  freezeRender() {
    this._freezeRender = true;
  }

  unfreezeRender() {
    this._freezeRender = false;
  }

  floatingWindow(node) {
    if (!node) return false;
    return node.nodeType === NODE_TYPES.WINDOW && node.mode === WINDOW_MODES.FLOAT;
  }

  /**
   * Moves the pointer along with the nodeWindow's meta
   *
   * This is useful for making sure that Forge calculates the attachNode
   * properly
   */
  movePointerWith(nodeWindow) {
    if (!nodeWindow || !nodeWindow._data) return;
    let rect = nodeWindow._data.get_frame_rect();
    global.get_pointer();
    const seat = Clutter.get_default_backend().get_default_seat();
    seat.warp_pointer(rect.x, rect.y);
  }

  getPointer() {
    return global.get_pointer();
  }

  minimizedWindow(node) {
    if (!node) return false;
    return node._type === NODE_TYPES.WINDOW && node._data && node._data.minimized;
  }

  swapWindowsUnderPointer(focusNodeWindow) {
    if (this.cancelGrab) {
      return;
    }
    let nodeWinAtPointer = this.findNodeWindowAtPointer(focusNodeWindow);
    if (nodeWinAtPointer) this.tree.swapPairs(focusNodeWindow, nodeWinAtPointer);
  }

  /**
   *
   * Handle previewing and applying where a drag-drop window is going to be tiled
   *
   */
  moveWindowToPointer(focusNodeWindow, preview = false) {
    if (this.cancelGrab) {
      return;
    }
    if (!focusNodeWindow || focusNodeWindow.mode !== WINDOW_MODES.GRAB_TILE) return;

    let nodeWinAtPointer = this.nodeWinAtPointer;

    if (nodeWinAtPointer) {
      const targetRect = nodeWinAtPointer.nodeValue.get_frame_rect();
      const parentNodeTarget = nodeWinAtPointer.parentNode;
      const currPointer = this.getPointer();
      const horizontal = parentNodeTarget.isHSplit() || parentNodeTarget.isTabbed();
      const isMonParent = parentNodeTarget.nodeType === NODE_TYPES.MONITOR;
      const isConParent = parentNodeTarget.nodeType === NODE_TYPES.CON;
      const stacked = parentNodeTarget.isStacked();
      const tabbed = parentNodeTarget.isTabbed();
      const stackedOrTabbed = stacked || tabbed;
      const updatePreview = (focusNodeWindow, previewParams) => {
        let previewHint = focusNodeWindow.previewHint;
        let previewHintEnabled = this.ext.settings.get_boolean("preview-hint-enabled");
        const previewRect = previewParams.targetRect;
        if (previewHint && previewHintEnabled) {
          if (!previewRect) {
            previewHint.hide();
            return;
          }
          previewHint.set_style_class_name(previewParams.className);
          previewHint.set_position(previewRect.x, previewRect.y);
          previewHint.set_size(previewRect.width, previewRect.height);
          previewHint.show();
        }
      };
      const regions = (targetRect, regionWidth) => {
        leftRegion = {
          x: targetRect.x,
          y: targetRect.y,
          width: targetRect.width * regionWidth,
          height: targetRect.height,
        };

        rightRegion = {
          x: targetRect.x + targetRect.width * (1 - regionWidth),
          y: targetRect.y,
          width: targetRect.width * regionWidth,
          height: targetRect.height,
        };

        topRegion = {
          x: targetRect.x,
          y: targetRect.y,
          width: targetRect.width,
          height: targetRect.height * regionWidth,
        };

        bottomRegion = {
          x: targetRect.x,
          y: targetRect.y + targetRect.height * (1 - regionWidth),
          width: targetRect.width,
          height: targetRect.height * regionWidth,
        };

        centerRegion = {
          x: targetRect.x + targetRect.width * regionWidth,
          y: targetRect.y + targetRect.height * regionWidth,
          width: targetRect.width - targetRect.width * regionWidth * 2,
          height: targetRect.height - targetRect.height * regionWidth * 2,
        };

        return {
          left: leftRegion,
          right: rightRegion,
          top: topRegion,
          bottom: bottomRegion,
          center: centerRegion,
        };
      };
      let referenceNode = null;
      let containerNode;
      let childNode = focusNodeWindow;
      let previewParams = {
        className: "",
        targetRect: null,
      };
      let leftRegion;
      let rightRegion;
      let topRegion;
      let bottomRegion;
      let centerRegion;
      let previewWidth = 0.5;
      let hoverWidth = 0.3;

      // Hover region detects where the pointer is on the target drop window
      const hoverRegions = regions(targetRect, hoverWidth);

      // Preview region interprets the hover intersect where the focus window
      // would go when dropped
      const previewRegions = regions(targetRect, previewWidth);

      leftRegion = hoverRegions.left;
      rightRegion = hoverRegions.right;
      topRegion = hoverRegions.top;
      bottomRegion = hoverRegions.bottom;
      centerRegion = hoverRegions.center;

      const isLeft = Utils.rectContainsPoint(leftRegion, currPointer);
      const isRight = Utils.rectContainsPoint(rightRegion, currPointer);
      const isTop = Utils.rectContainsPoint(topRegion, currPointer);
      const isBottom = Utils.rectContainsPoint(bottomRegion, currPointer);
      const isCenter = Utils.rectContainsPoint(centerRegion, currPointer);

      if (isCenter) {
        if (stackedOrTabbed) {
          containerNode = parentNodeTarget;
          referenceNode = null;
          previewParams = {
            className: stacked ? "window-tilepreview-stacked" : "window-tilepreview-tabbed",
            targetRect: targetRect,
          };
        } else {
          if (isMonParent) {
            childNode.createCon = true;
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer;
            previewParams = {
              targetRect: targetRect,
            };
          } else {
            containerNode = parentNodeTarget;
            referenceNode = null;
            const parentTargetRect = this.tree.processGap(parentNodeTarget);
            previewParams = {
              targetRect: parentTargetRect,
            };
          }
        }
      } else if (isLeft) {
        previewParams = {
          targetRect: previewRegions.left,
        };

        if (stackedOrTabbed) {
          // treat any windows on stacked or tabbed layouts to be
          // a single node unit: the con itself and then
          // split left, top, right or bottom accordingly (subsequent if conditions):
          childNode.detachWindow = true;
          if (!isMonParent) {
            referenceNode = parentNodeTarget;
            containerNode = parentNodeTarget.parentNode;
          } else {
            // It is a monitor that's a stack/tab
            // TODO: update the stacked/tabbed toggles to not
            // change layout if the parent is a monitor?
          }
        } else {
          if (horizontal) {
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer;
          } else {
            // vertical orientation
            childNode.createCon = true;
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer;
          }
        }
      } else if (isRight) {
        previewParams = {
          targetRect: previewRegions.right,
        };
        if (stackedOrTabbed) {
          // treat any windows on stacked or tabbed layouts to be
          // a single node unit: the con itself and then
          // split left, top, right or bottom accordingly (subsequent if conditions):
          childNode.detachWindow = true;
          if (!isMonParent) {
            referenceNode = parentNodeTarget.nextSibling;
            containerNode = parentNodeTarget.parentNode;
          } else {
            // It is a monitor that's a stack/tab
            // TODO: update the stacked/tabbed toggles to not
            // change layout if the parent is a monitor?
          }
        } else {
          if (horizontal) {
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer.nextSibling;
          } else {
            childNode.createCon = true;
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer.nextSibling;
          }
        }
      } else if (isTop) {
        previewParams = {
          targetRect: previewRegions.top,
        };
        if (stackedOrTabbed) {
          // treat any windows on stacked or tabbed layouts to be
          // a single node unit: the con itself and then
          // split left, top, right or bottom accordingly (subsequent if conditions):
          if (!isMonParent) {
            containerNode = parentNodeTarget;
            referenceNode = null;
            previewParams = {
              className: stacked ? "window-tilepreview-stacked" : "window-tilepreview-tabbed",
              targetRect: targetRect,
            };
          } else {
            // It is a monitor that's a stack/tab
            // TODO: update the stacked/tabbed toggles to not
            // change layout if the parent is a monitor?
          }
        } else {
          if (horizontal) {
            childNode.createCon = true;
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer;
          } else {
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer;
          }
        }
      } else if (isBottom) {
        previewParams = {
          targetRect: previewRegions.bottom,
        };
        if (stackedOrTabbed) {
          // treat any windows on stacked or tabbed layouts to be
          // a single node unit: the con itself and then
          // split left, top, right or bottom accordingly (subsequent if conditions):
          if (!isMonParent) {
            containerNode = parentNodeTarget;
            referenceNode = null;
            previewParams = {
              className: stacked ? "window-tilepreview-stacked" : "window-tilepreview-tabbed",
              targetRect: targetRect,
            };
          } else {
            // It is a monitor that's a stack/tab
            // TODO: update the stacked/tabbed toggles to not
            // change layout if the parent is a monitor?
          }
        } else {
          if (horizontal) {
            childNode = focusNodeWindow;
            childNode.createCon = true;
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer.nextSibling;
          } else {
            childNode = focusNodeWindow;
            containerNode = parentNodeTarget;
            referenceNode = nodeWinAtPointer.nextSibling;
          }
        }
      }

      if (!isCenter) {
        if (stackedOrTabbed) {
          if (isLeft || isRight) {
            previewParams.className = "window-tilepreview-tiled";
          } else if (isTop || isBottom) {
            previewParams.className = stacked
              ? "window-tilepreview-stacked"
              : "window-tilepreview-tabbed";
          }
        } else {
          previewParams.className = "window-tilepreview-tiled";
        }
      } else if (isCenter) {
        if (!stackedOrTabbed) previewParams.className = this._getDragDropCenterPreviewStyle();
      }

      if (!preview) {
        const previousParent = focusNodeWindow.parentNode;
        this.tree.resetSiblingPercent(containerNode);
        this.tree.resetSiblingPercent(previousParent);

        if (focusNodeWindow.tab) {
          let decoParent = focusNodeWindow.tab.get_parent();
          if (decoParent) decoParent.remove_child(focusNodeWindow.tab);
        }

        if (childNode.createCon) {
          const numWin = parentNodeTarget.childNodes.filter(
            (c) => c.nodeType === NODE_TYPES.WINDOW
          ).length;
          const numChild = parentNodeTarget.childNodes.length;
          const sameNumChild = numWin === numChild;
          // Child Node will still be created
          if (
            !isCenter &&
            ((isConParent && numWin === 1 && sameNumChild) ||
              (isMonParent && numWin == 2 && sameNumChild))
          ) {
            childNode = parentNodeTarget;
          } else {
            childNode = new Node(NODE_TYPES.CON, new St.Bin());
            containerNode.insertBefore(childNode, referenceNode);
            childNode.appendChild(nodeWinAtPointer);
          }

          if (isLeft || isTop) {
            childNode.insertBefore(focusNodeWindow, nodeWinAtPointer);
          } else if (isRight || isBottom || isCenter) {
            childNode.insertBefore(focusNodeWindow, null);
          }

          if (isLeft || isRight) {
            childNode.layout = LAYOUT_TYPES.HSPLIT;
          } else if (isTop || isBottom) {
            childNode.layout = LAYOUT_TYPES.VSPLIT;
          } else if (isCenter) {
            const centerLayout = this.ext.settings.get_string("dnd-center-layout").toUpperCase();
            childNode.layout = LAYOUT_TYPES[centerLayout];
          }
        } else if (childNode.detachWindow) {
          const orientation =
            isLeft || isRight ? ORIENTATION_TYPES.HORIZONTAL : ORIENTATION_TYPES.VERTICAL;
          this.tree.split(childNode, orientation);
          containerNode.insertBefore(childNode.parentNode, referenceNode);
        } else {
          // Child Node is a WINDOW
          containerNode.insertBefore(childNode, referenceNode);
          if (isLeft || isRight) {
            containerNode.layout = LAYOUT_TYPES.HSPLIT;
          } else if (isTop || isBottom) {
            if (!stackedOrTabbed) containerNode.layout = LAYOUT_TYPES.VSPLIT;
          } else if (isCenter) {
            if (containerNode.isHSplit() || containerNode.isVSplit()) {
              const centerLayout = this.ext.settings.get_string("dnd-center-layout").toUpperCase();
              containerNode.layout = LAYOUT_TYPES[centerLayout];
            }
          }
        }
      } else {
        updatePreview(focusNodeWindow, previewParams);
      }
      childNode.createCon = false;
      childNode.detachWindow = false;
    }
  }

  findNodeWindowAtPointer(focusNodeWindow) {
    let pointerCoord = global.get_pointer();

    let nodeWinAtPointer = this._findNodeWindowAtPointer(focusNodeWindow.nodeValue, pointerCoord);
    return nodeWinAtPointer;
  }

  /**
   * Finds the NodeWindow under the Meta.Window and the
   * current pointer coordinates;
   */
  _findNodeWindowAtPointer(metaWindow, pointer) {
    if (!metaWindow) return undefined;

    let sortedWindows = this.sortedWindows;

    if (!sortedWindows) {
      Logger.warn("No sorted windows");
      return;
    }

    for (let i = 0, n = sortedWindows.length; i < n; i++) {
      const w = sortedWindows[i];
      const metaRect = w.get_frame_rect();
      const atPointer = Utils.rectContainsPoint(metaRect, pointer);
      if (atPointer) return this.tree.getNodeByValue(w);
    }

    return null;
  }

  _handleGrabOpBegin(_display, _metaWindow, grabOp) {
    this.grabOp = grabOp;
    this.trackCurrentMonWs();
    let focusMetaWindow = this.focusMetaWindow;

    if (focusMetaWindow) {
      let focusNodeWindow = this.findNodeWindow(focusMetaWindow);
      if (!focusNodeWindow) return;

      const frameRect = focusMetaWindow.get_frame_rect();
      const gaps = this.calculateGaps(focusNodeWindow);

      focusNodeWindow.grabMode = Utils.grabMode(grabOp);
      if (
        focusNodeWindow.grabMode === GRAB_TYPES.MOVING &&
        focusNodeWindow.mode === WINDOW_MODES.TILE
      ) {
        this.freezeRender();
        focusNodeWindow.mode = WINDOW_MODES.GRAB_TILE;
      }

      focusNodeWindow.initGrabOp = grabOp;
      focusNodeWindow.initRect = Utils.removeGapOnRect(frameRect, gaps);
    }
  }

  _handleGrabOpEnd(_display, _metaWindow, grabOp) {
    this.unfreezeRender();
    let focusMetaWindow = this.focusMetaWindow;
    if (!focusMetaWindow) return;
    let focusNodeWindow = this.findNodeWindow(focusMetaWindow);

    if (focusNodeWindow && !this.cancelGrab) {
      // WINDOW_BASE is when grabbing the window decoration
      // COMPOSITOR is when something like Overview requesting a grab, especially when Super is pressed.
      if (
        grabOp === Meta.GrabOp.WINDOW_BASE ||
        grabOp === Meta.GrabOp.COMPOSITOR ||
        grabOp === Meta.GrabOp.MOVING_UNCONSTRAINED
      ) {
        if (this.allowDragDropTile()) {
          this.moveWindowToPointer(focusNodeWindow);
        }
      }
    }
    this._grabCleanup(focusNodeWindow);

    if (focusMetaWindow.get_maximized() === 0) {
      this.renderTree("grab-op-end");
    }

    this.updateStackedFocus(focusNodeWindow);
    this.updateTabbedFocus(focusNodeWindow);
    this.nodeWinAtPointer = null;
  }

  _grabCleanup(focusNodeWindow) {
    this.cancelGrab = false;
    if (!focusNodeWindow) return;
    focusNodeWindow.initRect = null;
    focusNodeWindow.grabMode = null;
    focusNodeWindow.initGrabOp = null;

    if (focusNodeWindow.previewHint) {
      focusNodeWindow.previewHint.hide();
      global.window_group.remove_child(focusNodeWindow.previewHint);
      focusNodeWindow.previewHint.destroy();
      focusNodeWindow.previewHint = null;
    }

    if (focusNodeWindow.mode === WINDOW_MODES.GRAB_TILE) {
      focusNodeWindow.mode = WINDOW_MODES.TILE;
    }
  }

  allowDragDropTile() {
    return this.kbd.allowDragDropTile();
  }

  _handleResizing(focusNodeWindow) {
    if (!focusNodeWindow || focusNodeWindow.isFloat()) return;
    let grabOp = this.grabOp;
    let initGrabOp = focusNodeWindow.initGrabOp;
    let direction = Utils.directionFromGrab(grabOp);
    let orientation = Utils.orientationFromGrab(grabOp);
    let parentNodeForFocus = focusNodeWindow.parentNode;
    let position = Utils.positionFromGrabOp(grabOp);
    // normalize the rect without gaps
    let frameRect = this.focusMetaWindow.get_frame_rect();
    let gaps = this.calculateGaps(focusNodeWindow);
    let currentRect = Utils.removeGapOnRect(frameRect, gaps);
    let firstRect;
    let secondRect;
    let parentRect;
    let resizePairForWindow;

    if (initGrabOp === Meta.GrabOp.RESIZING_UNKNOWN) {
      // the direction is null so do not process yet below.
      return;
    } else {
      resizePairForWindow = this.tree.nextVisible(focusNodeWindow, direction);
    }

    let sameParent = resizePairForWindow
      ? resizePairForWindow.parentNode === focusNodeWindow.parentNode
      : false;

    if (orientation === ORIENTATION_TYPES.HORIZONTAL) {
      if (sameParent) {
        // use the window or con pairs
        if (this.tree.getTiledChildren(parentNodeForFocus.childNodes).length <= 1) {
          return;
        }

        firstRect = focusNodeWindow.initRect;
        if (resizePairForWindow) {
          if (
            !this.floatingWindow(resizePairForWindow) &&
            !this.minimizedWindow(resizePairForWindow)
          ) {
            secondRect = resizePairForWindow.rect;
          } else {
            // TODO try to get the next resize pair?
          }
        }

        if (!firstRect || !secondRect) {
          return;
        }

        parentRect = parentNodeForFocus.rect;
        let changePx = currentRect.width - firstRect.width;
        let firstPercent = (firstRect.width + changePx) / parentRect.width;
        let secondPercent = (secondRect.width - changePx) / parentRect.width;
        focusNodeWindow.percent = firstPercent;
        resizePairForWindow.percent = secondPercent;
      } else {
        // use the parent pairs (con to another con or window)
        if (resizePairForWindow && resizePairForWindow.parentNode) {
          if (this.tree.getTiledChildren(resizePairForWindow.parentNode.childNodes).length <= 1) {
            return;
          }
          let firstWindowRect = focusNodeWindow.initRect;
          let index = resizePairForWindow.index;
          if (position === POSITION.BEFORE) {
            // Find the opposite node
            index = index + 1;
          } else {
            index = index - 1;
          }
          parentNodeForFocus = resizePairForWindow.parentNode.childNodes[index];
          firstRect = parentNodeForFocus.rect;
          secondRect = resizePairForWindow.rect;
          if (!firstRect || !secondRect) {
            return;
          }

          parentRect = parentNodeForFocus.parentNode.rect;
          let changePx = currentRect.width - firstWindowRect.width;
          let firstPercent = (firstRect.width + changePx) / parentRect.width;
          let secondPercent = (secondRect.width - changePx) / parentRect.width;
          parentNodeForFocus.percent = firstPercent;
          resizePairForWindow.percent = secondPercent;
        }
      }
    } else if (orientation === ORIENTATION_TYPES.VERTICAL) {
      if (sameParent) {
        // use the window or con pairs
        if (this.tree.getTiledChildren(parentNodeForFocus.childNodes).length <= 1) {
          return;
        }
        firstRect = focusNodeWindow.initRect;
        if (resizePairForWindow) {
          if (
            !this.floatingWindow(resizePairForWindow) &&
            !this.minimizedWindow(resizePairForWindow)
          ) {
            secondRect = resizePairForWindow.rect;
          } else {
            // TODO try to get the next resize pair?
          }
        }
        if (!firstRect || !secondRect) {
          return;
        }
        parentRect = parentNodeForFocus.rect;
        let changePx = currentRect.height - firstRect.height;
        let firstPercent = (firstRect.height + changePx) / parentRect.height;
        let secondPercent = (secondRect.height - changePx) / parentRect.height;
        focusNodeWindow.percent = firstPercent;
        resizePairForWindow.percent = secondPercent;
      } else {
        // use the parent pairs (con to another con or window)
        if (resizePairForWindow && resizePairForWindow.parentNode) {
          if (this.tree.getTiledChildren(resizePairForWindow.parentNode.childNodes).length <= 1) {
            return;
          }
          let firstWindowRect = focusNodeWindow.initRect;
          let index = resizePairForWindow.index;
          if (position === POSITION.BEFORE) {
            // Find the opposite node
            index = index + 1;
          } else {
            index = index - 1;
          }
          parentNodeForFocus = resizePairForWindow.parentNode.childNodes[index];
          firstRect = parentNodeForFocus.rect;
          secondRect = resizePairForWindow.rect;
          if (!firstRect || !secondRect) {
            return;
          }

          parentRect = parentNodeForFocus.parentNode.rect;
          let changePx = currentRect.height - firstWindowRect.height;
          let firstPercent = (firstRect.height + changePx) / parentRect.height;
          let secondPercent = (secondRect.height - changePx) / parentRect.height;
          parentNodeForFocus.percent = firstPercent;
          resizePairForWindow.percent = secondPercent;
        }
      }
    }
  }

  _handleMoving(focusNodeWindow) {
    if (!focusNodeWindow || focusNodeWindow.mode !== WINDOW_MODES.GRAB_TILE) return;

    const nodeWinAtPointer = this.findNodeWindowAtPointer(focusNodeWindow);
    this.nodeWinAtPointer = nodeWinAtPointer;

    const hidePreview = () => {
      if (focusNodeWindow.previewHint) {
        focusNodeWindow.previewHint.hide();
      }
    };

    if (nodeWinAtPointer) {
      if (!focusNodeWindow.previewHint) {
        let previewHint = new St.Bin();
        global.window_group.add_child(previewHint);
        focusNodeWindow.previewHint = previewHint;
      }

      if (this.allowDragDropTile()) {
        this.moveWindowToPointer(focusNodeWindow, true);
      } else {
        hidePreview();
      }
    } else {
      hidePreview();
    }
  }

  isFloatingExempt(metaWindow) {
    if (!metaWindow) return true;
    let windowTitle = metaWindow.get_title();
    let windowType = metaWindow.get_window_type();

    let floatByType =
      windowType === Meta.WindowType.DIALOG ||
      windowType === Meta.WindowType.MODAL_DIALOG ||
      metaWindow.get_transient_for() !== null ||
      metaWindow.get_wm_class() === null ||
      windowTitle === null ||
      windowTitle === "" ||
      windowTitle.length === 0 ||
      !metaWindow.allows_resize();

    const knownFloats = this.windowProps.overrides.filter((wprop) => wprop.mode === "float");

    let floatOverride =
      knownFloats.filter((kf) => {
        let matchTitle = false;
        let matchClass = false;

        if (kf.wmTitle) {
          if (kf.wmTitle === " ") {
            matchTitle = kf.wmTitle === windowTitle;
          } else {
            let titles = kf.wmTitle.split(",");
            matchTitle = titles.filter((t) => {
              if (windowTitle) {
                if (t.startsWith('!')) {
                  return !windowTitle.includes(t.slice(1))
                } else {
                  return windowTitle.includes(t)
                }
              }
              return false
            }).length > 0;
          }
        }
        if (kf.wmClass) {
          matchClass = kf.wmClass.includes(metaWindow.get_wm_class());
        }

        if (kf.wmClass && kf.wmTitle) {
          return matchTitle && matchClass;
        } else {
          if (kf.wmTitle) {
            return matchTitle;
          } else {
            return matchClass;
          }
        }
      }).length > 0;

    return floatByType || floatOverride;
  }

  _getDragDropCenterPreviewStyle() {
    const centerLayout = this.ext.settings.get_string("dnd-center-layout");
    return `window-tilepreview-${centerLayout}`;
  }

  get currentMonWsNode() {
    const monWs = this.currentMonWs;
    if (monWs) {
      return this.tree.findNode(monWs);
    }
    return null;
  }

  get currentWsNode() {
    const ws = this.currentWs;
    if (ws) {
      return this.tree.findNode(ws);
    }
    return null;
  }

  get currentMonWs() {
    const monWs = `${this.currentMon}${this.currentWs}`;
    return monWs;
  }

  get currentWs() {
    const display = global.display;
    const wsMgr = display.get_workspace_manager();
    return `ws${wsMgr.get_active_workspace_index()}`;
  }

  get currentMon() {
    const display = global.display;
    return `mo${display.get_current_monitor()}`;
  }

  floatAllWindows() {
    this.tree.getNodeByType(NODE_TYPES.WINDOW).forEach((w) => {
      if (w.isFloat()) {
        w.prevFloat = true;
      }
      w.mode = WINDOW_MODES.FLOAT;
    });
  }

  unfloatAllWindows() {
    this.tree.getNodeByType(NODE_TYPES.WINDOW).forEach((w) => {
      if (!w.prevFloat) {
        w.mode = WINDOW_MODES.TILE;
      } else {
        // Reset the float marker
        w.prevFloat = false;
      }
    });
  }
}