/*
 * Copyright (C)2005-2015 Haxe Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

@:enum abstract XmlType(Int) {
	var Element = 0;
	var PCData = 1;
	var CData = 2;
	var Comment = 3;
	var DocType = 4;
	var ProcessingInstruction = 5;
	var Document = 6;
}

class Xml {

	static public var Element(default,null) = XmlType.Element;
	static public var PCData(default,null) = XmlType.PCData;
	static public var CData(default,null) = XmlType.CData;
	static public var Comment(default,null) = XmlType.Comment;
	static public var DocType(default,null) = XmlType.DocType;
	static public var ProcessingInstruction(default,null) = XmlType.ProcessingInstruction;
	static public var Document(default,null) = XmlType.Document;

	static public function parse( str : String ) : Xml {
		return haxe.xml.Parser.parse(str);
	}

	/**
		Returns the type of the Xml Node. This should be used before
		accessing other functions since some might raise an exception
		if the node type is not correct.
	**/
	public var nodeType(default, null) : XmlType;

	/**
		Returns the node name of an Element.
	**/
	@:isVar public var nodeName(get, set) : String;

	/**
		Returns the node value. Only works if the Xml node is not an Element or a Document.
	**/
	@:isVar public var nodeValue(get, set) : String;

	/**
		Returns the parent object in the Xml hierarchy.
		The parent can be [null], an Element or a Document.
	**/
	public var parent(default, null) : Xml;

	var children:Array<Xml>;
	var attributeMap:Map<String, String>;

	inline function get_nodeName() {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		return nodeName;
	}

	inline function set_nodeName(v) {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		return this.nodeName = v;
	}

	inline function get_nodeValue() {
		if (nodeType == Document || nodeType == Element) {
			throw 'Bad node type, unexpected $nodeType';
		}
		return nodeValue;
	}

	inline function set_nodeValue(v) {
		if (nodeType == Document || nodeType == Element) {
			throw 'Bad node type, unexpected $nodeType';
		}
		return this.nodeValue = v;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createElement( name : String ) : Xml {
		var xml = new Xml(Element);
		xml.nodeName = name;
		return xml;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createPCData( data : String ) : Xml {
		var xml = new Xml(PCData);
		xml.nodeValue = data;
		return xml;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createCData( data : String ) : Xml {
		var xml = new Xml(CData);
		xml.nodeValue = data;
		return xml;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createComment( data : String ) : Xml {
		var xml = new Xml(Comment);
		xml.nodeValue = data;
		return xml;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createDocType( data : String ) : Xml {
		var xml = new Xml(DocType);
		xml.nodeValue = data;
		return xml;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createProcessingInstruction( data : String ) : Xml {
		var xml = new Xml(ProcessingInstruction);
		xml.nodeValue = data;
		return xml;
	}

	/**
		Creates a node of the given type.
	**/
	static public function createDocument() : Xml {
		return new Xml(Document);
	}

	/**
		Get the given attribute of an Element node. Returns [null] if not found.
		Attributes are case-sensitive.
	**/
	public function get( att : String ) : String {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		return attributeMap[att];
	}

	/**
		Set the given attribute value for an Element node.
		Attributes are case-sensitive.
	**/
	public function set( att : String, value : String ) : Void {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		attributeMap.set(att, value);
	}

	/**
		Removes an attribute for an Element node.
		Attributes are case-sensitive.
	**/
	public function remove( att : String ) : Void {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		attributeMap.remove(att);
	}

	/**
		Tells if the Element node has a given attribute.
		Attributes are case-sensitive.
	**/
	public function exists( att : String ) : Bool {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		return attributeMap.exists(att);
	}

	/**
		Returns an [Iterator] on all the attribute names.
	**/
	public function attributes() : Iterator<String> {
		if (nodeType != Element) {
			throw 'Bad node type, expected Element but found $nodeType';
		}
		return attributeMap.keys();
	}

	/**
		Returns an iterator of all child nodes.
		Only works if the current node is an Element or a Document.
	**/
	public inline function iterator() : Iterator<Xml> {
		ensureElementType();
		return children.iterator();
	}

	/**
		Returns an iterator of all child nodes which are Elements.
		Only works if the current node is an Element or a Document.
	**/
	public function elements() : Iterator<Xml> {
		ensureElementType();
		var ret = [for (child in children) if (child.nodeType == Element) child];
		return ret.iterator();
	}

	/**
		Returns an iterator of all child nodes which are Elements with the given nodeName.
		Only works if the current node is an Element or a Document.
	**/
	public function elementsNamed( name : String ) : Iterator<Xml> {
		ensureElementType();
		var ret = [for (child in children) if (child.nodeType == Element && child.nodeName == name) child];
		return ret.iterator();
	}

	/**
		Returns the first child node.
	**/
	public inline function firstChild() : Xml {
		ensureElementType();
		return children[0];
	}

	/**
		Returns the first child node which is an Element.
	**/
	public function firstElement() : Xml {
		ensureElementType();
		for (child in children) {
			if (child.nodeType == Element) {
				return child;
			}
		}
		return null;
	}

	/**
		Adds a child node to the Document or Element.
		A child node can only be inside one given parent node, which is indicated by the [parent] property.
		If the child is already inside this Document or Element, it will be moved to the last position among the Document or Element's children.
		If the child node was previously inside a different node, it will be moved to this Document or Element.
	**/
	public function addChild( x : Xml ) : Void {
		ensureElementType();
		if (x.parent != null) {
			x.parent.removeChild(x);
		}
		children.push(x);
		x.parent = this;
	}

	/**
		Removes a child from the Document or Element.
		Returns true if the child was successfuly removed.
	**/
	public function removeChild( x : Xml ) : Bool {
		ensureElementType();
		if (children.remove(x)) {
			x.parent = null;
			return true;
		}
		return false;
	}

	/**
		Inserts a child at the given position among the other childs.
		A child node can only be inside one given parent node, which is indicated by the [parent] property.
		If the child is already inside this Document or Element, it will be moved to the new position among the Document or Element's children.
		If the child node was previously inside a different node, it will be moved to this Document or Element.
	**/
	public function insertChild( x : Xml, pos : Int ) : Void {
		ensureElementType();
		if (x.parent != null) {
			x.parent.children.remove(x);
		}
		children.insert(pos, x);
		x.parent = this;
	}

	/**
		Returns a String representation of the Xml node.
	**/
	public inline function toString() : String {
		return haxe.xml.Printer.print(this);
	}

	function new(nodeType:XmlType) {
		this.nodeType = nodeType;
		children = [];
		attributeMap = new Map();
	}

	inline function ensureElementType() {
		if (nodeType != Document && nodeType != Element) {
			throw 'Bad node type, expected Element or Document but found $nodeType';
		}
	}
}