mediawiki-extensions-Visual.../modules/ve/dm/ve.dm.MetaItem.js

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/*!
* VisualEditor DataModel MetaItem class.
*
* @copyright 2011-2013 VisualEditor Team and others; see AUTHORS.txt
* @license The MIT License (MIT); see LICENSE.txt
*/
/**
* DataModel meta item.
*
* @class
* @abstract
* @extends ve.dm.Model
* @mixins ve.EventEmitter
*
* @constructor
* @param {Object} element Reference to element in meta-linmod
*/
ve.dm.MetaItem = function VeDmMetaItem( element ) {
// Parent constructor
ve.dm.Model.call( this, element );
// Mixin
ve.EventEmitter.call( this );
// Properties
this.list = null;
this.offset = null;
this.index = null;
this.move = null;
};
/* Inheritance */
ve.inheritClass( ve.dm.MetaItem, ve.dm.Model );
ve.mixinClass( ve.dm.MetaItem, ve.EventEmitter );
/* Static members */
/**
* Symbolic name for the group this meta item type will be grouped in in ve.dm.MetaList.
*
* @static
* @property {string} [static.group='misc']
* @inheritable
*/
ve.dm.MetaItem.static.group = 'misc';
/* Methods */
/**
* Remove this item from the document. Only works if the item is attached to a MetaList.
* @throws {Error} Cannot remove detached item
*/
ve.dm.MetaItem.prototype.remove = function () {
if ( !this.list ) {
throw new Error( 'Cannot remove detached item' );
}
this.list.removeMeta( this );
};
/**
* Get the group this meta item belongs to.
* @see ve.dm.MetaItem#static.group
* @returns {string} Group
*/
ve.dm.MetaItem.prototype.getGroup = function () {
return this.constructor.static.group;
};
/**
* Get the MetaList this item is attached to.
* @returns {ve.dm.MetaList|null} Reference to the parent list, or null if not attached
*/
ve.dm.MetaItem.prototype.getParentList = function () {
return this.list;
};
/**
* Get this item's offset in the linear model.
*
* This is only known if the item is attached to a MetaList.
*
* @returns {number|null} Offset, or null if not attached
*/
ve.dm.MetaItem.prototype.getOffset = function () {
return this.offset;
};
/**
* Get this item's index in the metadata array at the offset.
*
* This is only known if the item is attached to a MetaList.
*
* @returns {number|null} Index, or null if not attached
*/
ve.dm.MetaItem.prototype.getIndex = function () {
return this.index;
};
/**
* Set the offset. This is used by the parent list to synchronize the item with the document state.
* @param {number} offset New offset
*/
ve.dm.MetaItem.prototype.setOffset = function ( offset ) {
this.offset = offset;
};
/**
* Set the index. This is used by the parent list to synchronize the item with the document state.
* @param {number} index New index
*/
ve.dm.MetaItem.prototype.setIndex = function ( index ) {
this.index = index;
};
/**
* Queue up a change to the item's offset and index.
* @param {number} offset New offset
* @param {number} index New index
*/
ve.dm.MetaItem.prototype.setMove = function ( offset, index ) {
this.move = {
'offset': offset,
'index': index
};
};
/**
* Whether or not a move is pending.
* @returns {boolean} A move is pending
*/
ve.dm.MetaItem.prototype.isMovePending = function () {
return this.move !== null;
};
/**
* Apply the pending move and clear it.
* @throws No move pending
*/
ve.dm.MetaItem.prototype.applyMove = function () {
if ( this.move === null ) {
throw new Error( 'No move pending' );
}
this.setOffset( this.move.offset );
this.setIndex( this.move.index );
this.move = null;
};
/**
* Attach this item to a MetaList.
* @param {ve.dm.MetaList} list Parent list to attach to
* @param {number} offset Offset of this item in the parent list's document
* @param {number} index Index of this item in the metadata array at the offset
*/
ve.dm.MetaItem.prototype.attach = function ( list, offset, index ) {
this.list = list;
this.offset = offset;
this.index = index;
};
/**
* Detach this item from its parent list.
*
* This clears the stored offset and index, unless the item has already been attached to another list.
*
* @param {ve.dm.MetaList} list List to detach from
*/
ve.dm.MetaItem.prototype.detach = function ( list ) {
if ( this.list === list ) {
this.list = null;
this.offset = null;
this.index = null;
}
};