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//  Licensed to the Apache Software Foundation (ASF) under one or more
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//  this work for additional information regarding copyright ownership.
//  The ASF licenses this file to You under the Apache License, Version 2.0
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//
//      http://www.apache.org/licenses/LICENSE-2.0
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//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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////////////////////////////////////////////////////////////////////////////////
package flashx.textLayout.formats
{
	import flashx.textLayout.debug.Debugging;
	import flashx.textLayout.debug.assert;
	import flashx.textLayout.property.*;
	import flashx.textLayout.tlf_internal;
	use namespace tlf_internal;

	import flash.text.engine.TabAlignment;
	/**
	 * The TabStopFormat class represents the properties of a tab stop in a paragraph. You can set the <code>TextLayoutFormat.tabstops</code> property to an array of TabStopFormat objects.
	 * @includeExample examples\TabStopFormat_example.as -noswf
	 * @see flashx.textLayout.elements.TabElement 
	 * @see flashx.textLayout.formats.TextLayoutFormat#tabStops
	 * @playerversion Flash 10
	 * @playerversion AIR 1.5
	 * @langversion 3.0
	 */
	public class TabStopFormat implements ITabStopFormat
	{
		/** @private */
		static public const positionProperty:Property = Property.NewNumberProperty("position",0,false,Vector.<String>([Category.TABSTOP]),0,10000);
		/** @private */
		static public const alignmentProperty:Property = Property.NewEnumStringProperty(
			"alignment",TabAlignment.START,false,Vector.<String>([Category.TABSTOP])
			,TabAlignment.START
			,TabAlignment.CENTER
			,TabAlignment.END
			,TabAlignment.DECIMAL
		);
		/** @private */
		static public const decimalAlignmentTokenProperty:Property = Property.NewStringProperty("decimalAlignmentToken",null,false,Vector.<String>([Category.TABSTOP]));

		static private var _description:Object = {
			  position:positionProperty
			, alignment:alignmentProperty
			, decimalAlignmentToken:decimalAlignmentTokenProperty
		}

		/** Property descriptions accessible by name. @private */
		static tlf_internal function get description():Object
		{ return _description; }

		/** @private */
		static private var _emptyTabStopFormat:ITabStopFormat;
		/**
		 * Returns an ITabStopFormat instance with all properties set to <code>undefined</code>.
		 * @private
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		static tlf_internal function get emptyTabStopFormat():ITabStopFormat
		{
			if (_emptyTabStopFormat == null)
				_emptyTabStopFormat = new TabStopFormat();
			return _emptyTabStopFormat;
		}


		private var _position:*;
		private var _alignment:*;
		private var _decimalAlignmentToken:*;

		/**
		 * Return the value of the style specified by the <code>styleProp</code> parameter
		 * which specifies the style name.
		 * 
		 * @param styleProp The name of the style whose value is to be retrieved.
		 * @return The value of the specified style.  The type varies depending on the type of the style being
		 * accessed.  Returns <code>undefined</code> if the style is not set.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function getStyle(styleName:String):*
		{ return this[styleName]; }

		/**
		 * Set the value of the style specified by the <code>styleProp</code> parameter
		 * which specifies the style name to <code>value</code>.
		 * 
		 * @param styleProp The name of the style whose value is to be set.
		 * @param value The value to set.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function setStyle(styleName:String,value:*):void
		{ this[styleName] = value; }

		/**
		 * The position of the tab stop, in pixels, relative to the start edge of the column.
		 * <p>Legal values are numbers from 0 to 10000 and FormatValue.INHERIT.</p>
		 * <p>Default value is undefined indicating not set.</p>
		 * <p>If undefined during the cascade this property will have a value of 0.</p>
		 * @see FormatValue#INHERIT
		 * 
		 * @throws RangeError when set value is not within range for this property
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function get position():*
		{ return _position; }
		public function set position(newValue:*):void
		{ _position = positionProperty.setHelper(_position,newValue); }

		[Inspectable(enumeration="start,center,end,decimal,inherit")]
		/**
		 * The tab alignment for this tab stop. 
		 * <p>Legal values are TabAlignment.START, TabAlignment.CENTER, TabAlignment.END, TabAlignment.DECIMAL, FormatValue.INHERIT.</p>
		 * <p>Default value is undefined indicating not set.</p>
		 * <p>If undefined during the cascade this property will have a value of TabAlignment.START.</p>
		 * @see FormatValue#INHERIT
		 * 
		 * @throws RangeError when set value is not within range for this property
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 * @see flash.text.engine.TabAlignment
		 */
		public function get alignment():*
		{ return _alignment; }
		public function set alignment(newValue:*):void
		{ _alignment = alignmentProperty.setHelper(_alignment,newValue); }

		/**
		 * The alignment token to be used if the alignment is DECIMAL.
		 * <p>Default value is undefined indicating not set.</p>
		 * <p>If undefined during the cascade this property will have a value of null.</p>
		 * 
		 * @throws RangeError when set value is not within range for this property
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function get decimalAlignmentToken():*
		{ return _decimalAlignmentToken; }
		public function set decimalAlignmentToken(newValue:*):void
		{ _decimalAlignmentToken = decimalAlignmentTokenProperty.setHelper(_decimalAlignmentToken,newValue); }

		/**
		 * Creates a new TabStopFormat object. All settings are empty or, optionally, are initialized from the
		 * supplied <code>initialValues</code> object.
		 * 
		 * @param initialValues optional instance from which to copy initial values.
		 * 
		 * @see #defaultFormat
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function TabStopFormat(initialValues:ITabStopFormat = null)
		{
			if (initialValues)
				apply(initialValues)
		}

		/**
		 * Copies TabStopFormat settings from the <code>values</code> ITabStopFormat instance into this TabStopFormat object.
		 * If <code>values</code> is <code>null</code>, this TabStopFormat object is initialized with undefined values for all properties.
		 * @param values optional instance from which to copy values.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function copy(values:ITabStopFormat):void
		{
			 if (values == null)
				values = emptyTabStopFormat;
			this.position = values.position;
			this.alignment = values.alignment;
			this.decimalAlignmentToken = values.decimalAlignmentToken;
		}

		/**
		 * Concatenates the values of properties in the <code>incoming</code> ITabStopFormat instance
		 * with the values of this TabStopFormat object. In this (the receiving) TabStopFormat object, properties whose values are <code>FormatValue.INHERIT</code>,
		 * and inheriting properties whose values are <code>undefined</code> will get new values from the <code>incoming</code> object.
		 * Non-inheriting properties whose values are <code>undefined</code> will get their default values.
		 * All other property values will remain unmodified.
		 * 
		 * @param incoming instance from which values are concatenated.
		 * @see flashx.textLayout.formats.FormatValue#INHERIT
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function concat(incoming:ITabStopFormat):void
		{
			this.position = positionProperty.concatHelper(this.position, incoming.position);
			this.alignment = alignmentProperty.concatHelper(this.alignment, incoming.alignment);
			this.decimalAlignmentToken = decimalAlignmentTokenProperty.concatHelper(this.decimalAlignmentToken, incoming.decimalAlignmentToken);
		}

		/**
		 * Concatenates the values of properties in the <code>incoming</code> ITabStopFormat instance
		 * with the values of this TabStopFormat object. In this (the receiving) TabStopFormat object, properties whose values are <code>FormatValue.INHERIT</code>,
		 * and inheriting properties whose values are <code>undefined</code> will get new values from the <code>incoming</code> object.
		 * All other property values will remain unmodified.
		 * 
		 * @param incoming instance from which values are concatenated.
		 * @see flashx.textLayout.formats.FormatValue#INHERIT
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function concatInheritOnly(incoming:ITabStopFormat):void
		{
			this.position = positionProperty.concatInheritOnlyHelper(this.position, incoming.position);
			this.alignment = alignmentProperty.concatInheritOnlyHelper(this.alignment, incoming.alignment);
			this.decimalAlignmentToken = decimalAlignmentTokenProperty.concatInheritOnlyHelper(this.decimalAlignmentToken, incoming.decimalAlignmentToken);
		}

		/**
		 * Replaces property values in this TabStopFormat object with the values of properties that are set in
		 * the <code>incoming</code> ITabStopFormat instance. Properties that are <code>undefined</code> in the <code>incoming</code>
		 * ITabStopFormat instance are not changed in this object.
		 * 
		 * @param incoming instance whose property values are applied to this TabStopFormat object.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function apply(incoming:ITabStopFormat):void
		{
			var val:*;

			if ((val = incoming.position) !== undefined)
				this.position = val;
			if ((val = incoming.alignment) !== undefined)
				this.alignment = val;
			if ((val = incoming.decimalAlignmentToken) !== undefined)
				this.decimalAlignmentToken = val;
		}

		/**
		 * Compares properties in ITabStopFormat instance <code>p1</code> with properties in ITabStopFormat instance <code>p2</code>
		 * and returns <code>true</code> if all properties match.
		 * 
		 * @param p1 instance to compare to <code>p2</code>.
		 * @param p2 instance to compare to <code>p1</code>.
		 * 
		 * @return true if all properties match, false otherwise.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		static public function isEqual(p1:ITabStopFormat,p2:ITabStopFormat):Boolean
		{
			if (p1 == null)
				p1 = emptyTabStopFormat;
			if (p2 == null)
				p2 = emptyTabStopFormat;
			if (p1 == p2)
				return true;

			if (!positionProperty.equalHelper(p1.position, p2.position))
				return false;
			if (!alignmentProperty.equalHelper(p1.alignment, p2.alignment))
				return false;
			if (!decimalAlignmentTokenProperty.equalHelper(p1.decimalAlignmentToken, p2.decimalAlignmentToken))
				return false;

			return true;
		}

		/**
		 * Sets properties in this TabStopFormat object to <code>undefined</code> if they match those in the <code>incoming</code>
		 * ITabStopFormat instance.
		 * 
		 * @param incoming instance against which to compare this TabStopFormat object's property values.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function removeMatching(incoming:ITabStopFormat):void
		{
			if (incoming == null)
				return;

			if (positionProperty.equalHelper(this.position, incoming.position))
				this.position = undefined;
			if (alignmentProperty.equalHelper(this.alignment, incoming.alignment))
				this.alignment = undefined;
			if (decimalAlignmentTokenProperty.equalHelper(this.decimalAlignmentToken, incoming.decimalAlignmentToken))
				this.decimalAlignmentToken = undefined;
		}

		/**
		 * Sets properties in this TabStopFormat object to <code>undefined</code> if they do not match those in the
		 * <code>incoming</code> ITabStopFormat instance.
		 * 
		 * @param incoming instance against which to compare this TabStopFormat object's property values.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		public function removeClashing(incoming:ITabStopFormat):void
		{
			if (incoming == null)
				return;

			if (!positionProperty.equalHelper(this.position, incoming.position))
				this.position = undefined;
			if (!alignmentProperty.equalHelper(this.alignment, incoming.alignment))
				this.alignment = undefined;
			if (!decimalAlignmentTokenProperty.equalHelper(this.decimalAlignmentToken, incoming.decimalAlignmentToken))
				this.decimalAlignmentToken = undefined;
		}

		static private var _defaults:TabStopFormat;
		/**
		 * Returns a TabStopFormat object with default settings.
		 * This function always returns the same object.
		 * 
		 * @return a singleton instance of ITabStopFormat that is populated with default values.
		 * 
		 * @playerversion Flash 10
		 * @playerversion AIR 1.5
		 * @langversion 3.0
		 */
		static public function get defaultFormat():ITabStopFormat
		{
			if (_defaults == null)
			{
				_defaults = new TabStopFormat();
				Property.defaultsAllHelper(_description,_defaults);
			}
			return _defaults;
		}
	}
}