/* -*- mode: js2; js2-basic-offset: 4; indent-tabs-mode: nil -*- */

const Clutter = imports.gi.Clutter;
const Mainloop = imports.mainloop;
const Meta = imports.gi.Meta;
const Shell = imports.gi.Shell;
const Tweener = imports.tweener.tweener;

const Main = imports.ui.main;

const SWITCH_ANIMATION_TIME = 0.5;

function WindowManager() {
    this._init();
}

WindowManager.prototype = {
    _init : function() {
        let me = this;

        this._global = Shell.Global.get();
        this._shellwm = this._global.window_manager;

        this._switchData = null;
        this._shellwm.connect('switch-workspace',
            function(o, from, to, direction) {
                let actors = me._shellwm.get_switch_workspace_actors();
                me.switchWorkspace(actors, from, to, direction);
            });
        this._shellwm.connect('kill-switch-workspace',
            function(o) {
                me.switchWorkspaceDone();
            });
    },

    switchWorkspace : function(windows, from, to, direction) {
        // If the overlay is active, it will do the transition itself
        if (Main.overlayActive) {
            this._shellwm.completed_switch_workspace();
            return;
        }

        /* @direction is the direction that the "camera" moves, so the
         * screen contents have to move one screen's worth in the
         * opposite direction.
         */
        let xDest = 0, yDest = 0;

        if (direction == Meta.MotionDirection.UP ||
            direction == Meta.MotionDirection.UP_LEFT ||
            direction == Meta.MotionDirection.UP_RIGHT)
                yDest = this._global.screen_height;
        else if (direction == Meta.MotionDirection.DOWN ||
            direction == Meta.MotionDirection.DOWN_LEFT ||
            direction == Meta.MotionDirection.DOWN_RIGHT)
                yDest = -this._global.screen_height;

        if (direction == Meta.MotionDirection.LEFT ||
            direction == Meta.MotionDirection.UP_LEFT ||
            direction == Meta.MotionDirection.DOWN_LEFT)
                xDest = this._global.screen_width;
        else if (direction == Meta.MotionDirection.RIGHT ||
                 direction == Meta.MotionDirection.UP_RIGHT ||
                 direction == Meta.MotionDirection.DOWN_RIGHT)
                xDest = -this._global.screen_width;

        let switchData = {};
        this._switchData = switchData;
        switchData.inGroup = new Clutter.Group();
        switchData.outGroup = new Clutter.Group();
        switchData.windows = [];

        let wgroup = this._global.window_group;
        wgroup.add_actor(switchData.inGroup);
        wgroup.add_actor(switchData.outGroup);

        for (let i = 0; i < windows.length; i++) {
            let window = windows[i];
            if (window.get_workspace() == from) {
                switchData.windows.push({ window: window,
                                          parent: window.get_parent() });
                window.reparent(switchData.outGroup);
            } else if (window.get_workspace() == to) {
                switchData.windows.push({ window: window,
                                          parent: window.get_parent() });
                window.reparent(switchData.inGroup);
                window.show_all();
            }
        }

        switchData.inGroup.set_position(-xDest, -yDest);
        switchData.inGroup.raise_top();

        Tweener.addTween(switchData.outGroup,
                         { x: xDest,
                           y: yDest,
                           time: SWITCH_ANIMATION_TIME,
                           transition: "easeOutBack",
                           onComplete: this.switchWorkspaceDone
                         });
        Tweener.addTween(switchData.inGroup,
                         { x: 0,
                           y: 0,
                           time: SWITCH_ANIMATION_TIME,
                           transition: "easeOutBack"
                         });
    },

    switchWorkspaceDone : function() {
        let switchData = this._switchData;
        if (!switchData)
            return;
        this._switchData = null;

        for (let i = 0; i < switchData.windows.length; i++) {
                let w = switchData.windows[i];
                if (w.window.get_parent() == switchData.outGroup) {
                    w.window.reparent(w.parent);
                    w.window.hide();
                } else
                    w.window.reparent(w.parent);
        }
        Tweener.removeTweens(switchData.inGroup);
        Tweener.removeTweens(switchData.outGroup);
        switchData.inGroup.destroy();
        switchData.outGroup.destroy();

        this._shellwm.completed_switch_workspace();
    }

};