/*
 *
 * (c) Copyright Ascensio System Limited 2010-2016
 *
 * This program is a free software product. You can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License (AGPL)
 * version 3 as published by the Free Software Foundation. In accordance with
 * Section 7(a) of the GNU AGPL its Section 15 shall be amended to the effect
 * that Ascensio System SIA expressly excludes the warranty of non-infringement
 * of any third-party rights.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For
 * details, see the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA at Lubanas st. 125a-25, Riga, Latvia,
 * EU, LV-1021.
 *
 * The  interactive user interfaces in modified source and object code versions
 * of the Program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU AGPL version 3.
 *
 * Pursuant to Section 7(b) of the License you must retain the original Product
 * logo when distributing the program. Pursuant to Section 7(e) we decline to
 * grant you any rights under trademark law for use of our trademarks.
 *
 * All the Product's GUI elements, including illustrations and icon sets, as
 * well as technical writing content are licensed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International. See the License
 * terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
*/
/**
 *    TabBar.js
 *
 *    Created by Maxim Kadushkin on 28 March 2014
 *    Copyright (c) 2014 Ascensio System SIA. All rights reserved.
 *
 */

define([
    'common/main/lib/component/BaseView',
    'common/main/lib/component/Tab'
], function () {
    'use strict';

    var Events = {
        bind: function () {
            if (!this.o) this.o = $({});
            this.o.on.apply(this.o, arguments);
        },
        unbind: function () {
            if (this.o) this.o.off.apply(this.o, arguments);
        },
        trigger: function () {
            if (!this.o) this.o = $({});
            this.o.trigger.apply(this.o, arguments);
        }
    };

    var StateManager = function (options) {
        this.initialize.call(this, options);
    };

    _.extend(StateManager.prototype, Events);

    StateManager.prototype.initialize = function (options) {
        this.bar = options.bar;
    };

    StateManager.prototype.attach = function (tab) {
        tab.changeState = $.proxy(function () {
            this.trigger('tab:change', tab);
            this.bar.$el.find('ul > li.active').removeClass('active');
            tab.activate();

            this.bar.trigger('tab:changed', this.bar, this.bar.tabs.indexOf(tab), tab);
        }, this);

        var dragHelper = new (function() {

            return {
                bounds: [],
                drag: undefined,

                calculateBounds: function () {
                    var me = this,
                        length = me.bar.tabs.length,
                        barBounds = me.bar.$bar.get(0).getBoundingClientRect();

                    if (barBounds) {
                        me.bounds       = [];
                        me.scrollLeft   = me.bar.$bar.scrollLeft();
                        me.bar.scrollX  = this.scrollLeft;

                        for (var i = 0; i < length; ++i) {
                            this.bounds.push(me.bar.tabs[i].$el.get(0).getBoundingClientRect());
                        }

                        me.tabBarLeft   = me.bounds[0].left;
                        me.tabBarRight  = me.bounds[length - 1].right;
                        me.tabBarRight  = Math.min(me.tabBarRight, barBounds.right - 1);
                    }
                },

                setAbsTabs: function () {
                    var me = this, tab = null, length = this.bounds.length;

                    for (var i = 0; i < length; ++i) {
                        tab = me.bar.tabs[i].$el;
                        tab.css('position', 'absolute');
                        tab.css('left', (me.bounds[i].left - me.tabBarLeft - this.scrollLeft) + 'px');

                        if (tab.hasClass('active')) {
                            tab.css('top', '1px');
                        } else {
                            tab.css('top', '0px');
                        }
                    }
                },

                updatePositions: function () {
                    this.drag.place = undefined;

                    var i, tabBound, center, place = -1, next = -this.scrollLeft,
                        tabsCount = this.bounds.length,
                        dragBound = this.drag.tab.$el.get(0).getBoundingClientRect();

                    if (this.drag.moveX - this.drag.mouseX > 0) {
                        for (i = tabsCount - 1; i >= 0; --i) {
                            tabBound = this.bounds[i];
                            center = (tabBound.right + tabBound.left) * 0.5;
                            if (dragBound.left < center && center < dragBound.right) {
                                place = i;
                                break;
                            }
                        }

                        if (-1 === place) {
                            for (i = tabsCount - 1; i >= 0; --i) {
                                tabBound = dragBound;
                                center = (tabBound.right + tabBound.left) * 0.5;
                                if (this.bounds[i].left < center && center < this.bounds[i].right) {
                                    place = i;
                                    break;
                                }
                            }
                        }

                    } else {
                        for (i = 0; i < tabsCount; ++i) {
                            tabBound = this.bounds[i];
                            center = (tabBound.right + tabBound.left) * 0.5;
                            if (dragBound.left < center && center < dragBound.right) {
                                place = i;
                                break;
                            }
                        }

                        if (-1 === place) {
                            for (i = 0; i < tabsCount; ++i) {
                                tabBound = dragBound;
                                center = (tabBound.right + tabBound.left) * 0.5;
                                if (this.bounds[i].left < center && center < this.bounds[i].right) {
                                    place = i;
                                    break;
                                }
                            }
                        }
                    }

                    if (-1 !== place) {

                        this.drag.place = place;

                        for (i = 0; i < tabsCount; ++i) {
                            if (i === place) {
                                if (place < this.drag.index) {
                                    next += this.drag.tabWidth;
                                }
                            }

                            if (place > this.drag.index) {
                                if (i === place + 1) {
                                    next += this.drag.tabWidth;
                                }
                            }

                            if (i !== this.drag.index) {
                                this.bar.tabs[i].$el.css('left', next + 'px');
                            } else {
                                if (this.drag.index === place) {
                                    next += this.drag.tabWidth;
                                }

                                continue;
                            }

                            next += this.bounds[i].width;
                        }
                    }
                },

                setHook: function(e, bar, tab) {
                    var me = this;

                    function dragComplete() {
                        if (!_.isUndefined(me.drag)) {
                            me.drag.tab.$el.css('z-index', '');

                            var tab = null;
                            for (var i = me.bar.tabs.length - 1; i >= 0; --i) {
                                tab = me.bar.tabs[i].$el;
                                if (tab) {
                                    tab.css('top', '');
                                    tab.css('position', '');
                                    tab.css('left', '');
                                }
                            }

                            if (!_.isUndefined(me.drag.place)) {
                                me.bar.trigger('tab:move', me.drag.index, me.drag.place);
                                me.bar.$bar.scrollLeft(me.scrollLeft);
                                me.bar.scrollX = undefined;
                            } else {
                                me.bar.trigger('tab:move', me.drag.index);
                                me.bar.$bar.scrollLeft(me.scrollLeft);
                                me.bar.scrollX = undefined;
                            }

                            me.drag  = undefined;
                        }
                    }

                    function dragMove (e) {
                        if (!_.isUndefined(me.drag)) {
                            me.drag.moveX = e.clientX*Common.Utils.zoom();
                            var leftPos = Math.max(me.drag.moveX - me.drag.anchorX - me.tabBarLeft - me.scrollLeft, 0);
                            leftPos = Math.min(leftPos, me.tabBarRight - me.tabBarLeft - me.drag.tabWidth - me.scrollLeft);

                            me.drag.tab.$el.css('left', leftPos + 'px');
                            me.drag.tab.$el.css('z-index','100');

                            me.updatePositions();
                        }
                    }

                    function dragDropText (e) { // disable firefox drag&drop
                        e.preventDefault();
                    }

                    if (!_.isUndefined(bar) && !_.isUndefined(tab) && bar.tabs.length > 1) {
                        var index   = bar.tabs.indexOf(tab),
                            _clientX = e.clientX*Common.Utils.zoom();
                        me.bar      = bar;
                        me.drag     = {tab: tab, index: index};

                        this.calculateBounds();
                        this.setAbsTabs();

                        me.drag.moveX       = _clientX;
                        me.drag.mouseX      = _clientX;
                        me.drag.anchorX     = _clientX - this.bounds[index].left;
                        me.drag.tabWidth    = this.bounds[index].width;

                        document.addEventListener('dragstart',dragDropText);

                        $(document).on('mousemove.tabbar', dragMove);
                        $(document).on('mouseup.tabbar', function (e) {
                            dragComplete(e);
                            $(document).off('mouseup.tabbar');
                            $(document).off('mousemove.tabbar');

                            document.removeEventListener('dragstart',dragDropText);
                        });
                    }
                }
            }
        });

        tab.$el.on({
            click: $.proxy(function () {
                if (!tab.disabled && !tab.$el.hasClass('active')) {
                    if (tab.control == 'manual') {
                        this.bar.trigger('tab:manual', this.bar, this.bar.tabs.indexOf(tab), tab);
                    } else {
                        tab.changeState();
                    }
                }
            }, this),
            dblclick: $.proxy(function() {
                this.trigger('tab:dblclick', this, this.tabs.indexOf(tab), tab);
            }, this.bar),
            contextmenu: $.proxy(function () {
                this.trigger('tab:contextmenu', this, this.tabs.indexOf(tab), tab);
            }, this.bar),
            mousedown: $.proxy(function (e) {
                if (this.bar.options.draggable && !_.isUndefined(dragHelper) && (3 !== e.which)) {
                    if (!tab.isLockTheDrag) {
                        dragHelper.setHook(e, this.bar, tab);
                    }
                }
            }, this)
        });
    };

    StateManager.prototype.detach = function (tab) {
        tab.$el.off();
    };

    Common.UI.TabBar = Common.UI.BaseView.extend({
        config: {
            placement   : 'top',
            items       : [],
            draggable   : false
        },

        tabs: [],
        template: _.template('<ul class="nav nav-tabs <%= placement %>" />'),

        initialize : function (options) {
            _.extend(this.config, options);
            Common.UI.BaseView.prototype.initialize.call(this, options);

            this.saved = [];
        },

        render: function () {
            this.$el.html(this.template(this.config));
            this.$bar = this.$el.find('ul');

            var addEvent = function( elem, type, fn ) {
                elem.addEventListener ? elem.addEventListener( type, fn, false ) : elem.attachEvent( "on" + type, fn );
            };

            var eventname=(/Firefox/i.test(navigator.userAgent))? 'DOMMouseScroll' : 'mousewheel';
            addEvent(this.$bar[0], eventname, _.bind(this._onMouseWheel,this));

            this.manager = new StateManager({bar: this});

            this.insert(-1, this.config.items);
            this.insert(-1, this.saved);
            delete this.saved;

            this.rendered = true;
            return this;
        },

        _onMouseWheel: function(e) {
            var hidden  = this.checkInvisible(true),
                forward = ((e.detail && -e.detail) || e.wheelDelta) > 0;

            if (forward) {
                if (hidden.last) {
                    this.setTabVisible('forward');
                }
            } else {
                if (hidden.first) {
                    this.setTabVisible('backward');
                }
            }
        },

        add: function(tabs) {
            return this.insert(-1, tabs) > 0;
        },

        insert: function(index, tabs) {
            var count = 0;
            if (tabs) {
                if (!(tabs instanceof Array)) tabs = [tabs];

                if (tabs.length) {
                    count = tabs.length;

                    if (this.rendered) {
                        var me = this, tab;

                        if (index < 0 || index > me.tabs.length) {
                            for (var i = 0; i < tabs.length; i++) {
                                tab = new Common.UI.Tab(tabs[i]);
                                me.$bar.append(tab.render().$el);
                                me.tabs.push(tab);
                                me.manager.attach(tab);
                            }
                        } else {
                            for (i = tabs.length; i-- > 0 ; ) {
                                tab = new Common.UI.Tab(tabs[i]);

                                if (index === 0) {
                                    me.$bar.prepend(tab.render().$el);
                                    me.tabs.unshift(tab);
                                } else {
                                    me.$bar.find('li:nth-child(' + index + ')').before(tab.render().$el);
                                    me.tabs.splice(index, 0, tab);
                                }

                                me.manager.attach(tab);
                            }
                        }
                    } else {
                        this.saved.push(tabs)
                    }

                    this.checkInvisible();
                }
            }

            return count;
        },

        remove: function(index) {
            if (index >= 0 && index < this.tabs.length) {
                var tab = this.tabs.splice(index, 1)[0];
                this.manager.detach(tab);
                tab.$el.remove();
                this.checkInvisible();
            }
        },

        empty: function(suppress) {
            var me = this;
            this.tabs.forEach(function(tab){
                me.manager.detach(tab);
            });

            this.$bar.empty();
            me.tabs = [];

            this.checkInvisible(suppress);
        },

        setActive: function(t) {
            if (t instanceof Common.UI.Tab) {
                tab = t;
            } else
            if (typeof t == 'number') {
                if (t >= 0 && t < this.tabs.length) {
                    var tab = this.tabs[t];
                }
            }

            if(tab && tab.control != 'manual' && !tab.disabled && !tab.$el.hasClass('active')){
                tab.changeState();
            }

            this.checkInvisible();
        },

        getActive: function(iselem) {
            return iselem ? this.$bar.find('> li.active') : this.$bar.find('> li.active').index();
        },

        getAt: function(index) {
            return (index >= 0 && index < this.tabs.length) ? this.tabs[index] : undefined;
        },

        getCount: function() {
            return this.tabs.length;
        },

        addClass: function(cls) {
            if (cls.length && !this.$bar.hasClass(cls))
                this.$bar.addClass(cls);
        },

        removeClass: function(cls) {
            if (cls.length && this.$bar.hasClass(cls))
                this.$bar.removeClass(cls);
        },

        hasClass: function(cls) {
            return this.$bar.hasClass(cls);
        },

        setTabVisible: function(index, suppress) {
            if (index <= 0 || index == 'first') {
                this.$bar.scrollLeft(0);
                this.checkInvisible(suppress);
            } else if ( index >= (this.tabs.length - 1) || index == 'last') {
                var tab = this.tabs[this.tabs.length-1].$el;
                this.$bar.scrollLeft(this.$bar.scrollLeft() + (tab.position().left + parseInt(tab.css('width')) - this.$bar.width()) + 1);
                this.checkInvisible(suppress);
            } else {
                var rightbound = this.$bar.width(),
                    tab, right, left;

                if (index == 'forward') {
                    for (var i = 0; i < this.tabs.length; i++) {
                        tab = this.tabs[i].$el;
                        right = tab.position().left + parseInt(tab.css('width'));

                        if (right > rightbound) {
                            this.$bar.scrollLeft(this.$bar.scrollLeft() + (right - rightbound) + 20);
                            this.checkInvisible(suppress);
                            break;
                        }
                    }
                } else if (index == 'backward') {
                    for (i = this.tabs.length; i-- > 0; ) {
                        tab = this.tabs[i].$el;
                        left = tab.position().left;

                        if (left < 0) {
                            this.$bar.scrollLeft(this.$bar.scrollLeft() + left - 26);
                            this.checkInvisible(suppress);
                            break;
                        }
                    }
                } else if (typeof index == 'number') {
                    tab = this.tabs[index].$el;
                    left = tab.position().left;
                    right = left + parseInt(tab.css('width'));

                    if (left < 0) {
                        this.$bar.scrollLeft(this.$bar.scrollLeft() + left - 26);
                        this.checkInvisible(suppress);
                    } else if (right > rightbound) {
                        this.$bar.scrollLeft(this.$bar.scrollLeft() + (right - rightbound) + 20);
                        this.checkInvisible(suppress);
                    }
                }
            }
        },

        checkInvisible: function(suppress) {
            var result = {
                first: !this.isTabVisible(0),
                last: !this.isTabVisible(this.tabs.length-1)
            };

            !suppress && this.fireEvent('tab:invisible', this, result);
            return result;
        },

        hasInvisible: function() {
            var _left_bound_ = this.$bar.offset().left,
                _right_bound_ = _left_bound_ + this.$bar.width();

            for (var i = this.tabs.length; i-- > 0; ) {
                if (!this.isTabVisible(i, _left_bound_, _right_bound_)) {
                    return true;
                }
            }

            return false;
        },

        isTabVisible: function(index) {
            var leftbound = arguments[1] || this.$bar.offset().left,
                rightbound = arguments[2] || (leftbound + this.$bar.width()),
                left, right, tab, rect;

            if (index < this.tabs.length && index >= 0) {
                tab = this.tabs[index].$el;
                rect = tab.get(0).getBoundingClientRect();
                left = rect.left;
                right = rect.right;

                //left = tab.position().left;
                //right = left + tab.width();

                return !(left < leftbound) && !(right > rightbound);
            }

            return false;
        }
    });
});