/**
 * VisualEditor content editable TextNode class.
 *
 * @copyright 2011-2012 VisualEditor Team and others; see AUTHORS.txt
 * @license The MIT License (MIT); see LICENSE.txt
 */

/**
 * ContentEditable node for text.
 *
 * @class
 * @constructor
 * @extends {ve.ce.LeafNode}
 * @param model {ve.dm.TextNode} Model to observe
 */
ve.ce.TextNode = function ( model ) {
	// Inheritance
	ve.ce.LeafNode.call( this, 'text', model, $( document.createTextNode('') ) );
	
	// Events
	this.model.addListenerMethod( this, 'update', 'onUpdate' );

	// Intialization
	this.onUpdate( true );
};

/* Static Members */

/**
 * Node rules.
 *
 * @see ve.ce.NodeFactory
 * @static
 * @member
 */
ve.ce.TextNode.rules = {
	'canBeSplit': true
};

/**
 * Mapping of character and HTML entities or renderings.
 *
 * @static
 * @member
 */
ve.ce.TextNode.htmlCharacters = {
	'&': '&',
	'<': '&lt;',
	'>': '&gt;',
	'\'': '&#039;',
	'"': '&quot;',
	'\n': '&crarr;',
	'\t': '&#10142;'
};

/**
 * List of annotation rendering implementations.
 *
 * Each supported annotation renderer must have an open and close property, each either a string or
 * a function which accepts a data argument.
 *
 * @static
 * @member
 */
ve.ce.TextNode.annotationRenderers = {
	'textStyle/italic': {
		'open': '<i>',
		'close': '</i>'
	},
	'textStyle/bold': {
		'open': '<b>',
		'close': '</b>'
	},
	'textStyle/underline': {
		'open': '<u>',
		'close': '</u>'
	},
	'textStyle/strike': {
		'open': '<s>',
		'close': '</s>'
	},
	'textStyle/small': {
		'open': '<small>',
		'close': '</small>'
	},
	'textStyle/big': {
		'open': '<big>',
		'close': '</big>'
	},
	'textStyle/span': {
		// TODO recognize attributes
		'open': '<span>',
		'close': '</span>'
	},
	'textStyle/strong': {
		'open': '<strong>',
		'close': '</strong>'
	},
	'textStyle/emphasize': {
		'open': '<em>',
		'close': '<em>'
	},
	'textStyle/superScript': {
		'open': '<sup>',
		'close': '</sup>'
	},
	'textStyle/subScript': {
		'open': '<sub>',
		'close': '</sub>'
	},
	'link/ExtLink': {
		'open': function () {
			return '<a href="#">';
		},
		'close': '</a>'
	},
	'link/ExtLink/Numbered': {
		'open': function () {
			return '<a href="#">';
		},
		'close': '</a>'
	},
	'link/ExtLink/URL': {
		'open': function () {
			return '<a href="#">';
		},
		'close': '</a>'
	},
	'link/WikiLink': {
		'open': function () {
			return '<a href="#">';
		},
		'close': '</a>'
	},
	'link/unknown': {
		'open': function () {
			return '<a href="#">';
		},
		'close': '</a>'
	}
};

/* Methods */

/**
 * Responds to model update events.
 *
 * If the source changed since last update the image's src attribute will be updated accordingly.
 *
 * @method
 */
ve.ce.TextNode.prototype.onUpdate = function ( force ) {
	if ( !force && !this.root.getSurface ) {
		throw new Error( 'Can not update a text node that is not attached to a document' );
	}
	if ( force === true || this.root.getSurface().render === true ) {
		var $new = $( '<span>' ).html( this.getHtml() ).contents();
		if ( $new.length === 0 ) {
			$new = $new.add( document.createTextNode( '' ) );
		}
		this.$.replaceWith( $new );
		this.$ = $new;
		if ( this.parent ) {
			this.parent.clean();
			if ( ve.debug ) {
				this.parent.$.css( 'backgroundColor', '#F6F6F6' );
				setTimeout( ve.bind( function () {
					this.parent.$.css( 'backgroundColor', 'transparent' );
				}, this ), 350 );
			}
		}
	}
};

/**
 * Gets an HTML rendering of data within content model.
 *
 * @method
 * @param {String} Rendered HTML of data within content model
 */
ve.ce.TextNode.prototype.getHtml = function () {
	var data = this.model.getDocument().getDataFromNode( this.model ),
		htmlChars = ve.ce.TextNode.htmlCharacters,
		renderers = ve.ce.TextNode.annotationRenderers,
		out = '',
		i,
		j,
		hash,
		left = '',
		right,
		character,
		nextCharacter,
		open,
		close,
		index,
		leftPlain,
		rightPlain,
		hashStack = [],
		annotationStack = {},
		chr;

	function replaceWithNonBreakingSpace( index, data ) {
		if ( ve.isArray( data[index] ) ) {
			// Don't modify the original array, clone it first
			data[index] = data[index].slice( 0 );
			data[index][0] = '&nbsp;';
		} else {
			data[index] = '&nbsp;';
		}
	}

	if ( data.length > 0 ) {
		character = data[0];
		if ( ve.isArray( character ) ? character[0] === ' ' : character === ' ' ) {
			replaceWithNonBreakingSpace( 0, data );
		}
	}
	if ( data.length > 1 ) {
		character = data[data.length - 1];
		if ( ve.isArray( character ) ? character[0] === ' ' : character === ' ' ) {
			replaceWithNonBreakingSpace( data.length - 1, data );
		}
	}
	if ( data.length > 2 ) {
		for ( i = 1; i < data.length - 1; i++ ) {
			character = data[i];
			nextCharacter = data[i + 1];
			if (
				( ve.isArray( character ) ? character[0] === ' ' : character === ' ' ) &&
				( ve.isArray( nextCharacter ) ? nextCharacter[0] === ' ' : nextCharacter === ' ' )
			) {
				replaceWithNonBreakingSpace( i + 1, data );
				i++;
			}
		}
	}

	function openAnnotations( annotations ) {
		var out = '',
			annotation, hash;
		for ( hash in annotations ) {
			annotation = annotations[hash];
			out += typeof renderers[annotation.type].open === 'function' ?
				renderers[annotation.type].open( annotation.data ) :
				renderers[annotation.type].open;
			hashStack.push( hash );
			annotationStack[hash] = annotation;
		}
		return out;
	}

	function closeAnnotations( annotations ) {
		var out = '',
			annotation, hash;
		for ( hash in annotations ) {
			annotation = annotations[hash];
			out += typeof renderers[annotation.type].close === 'function' ?
				renderers[annotation.type].close( annotation.data ) :
				renderers[annotation.type].close;
			hashStack.pop();
			delete annotationStack[hash];
		}
		return out;
	}

	for ( i = 0; i < data.length; i++ ) {
		right = data[i];
		leftPlain = typeof left === 'string';
		rightPlain = typeof right === 'string';
		
		if ( !leftPlain && rightPlain ) {
			// [formatted][plain]
			close = {};
			for ( j = hashStack.length - 1; j >= 0; j-- ) {
				close[hashStack[j]] = annotationStack[hashStack[j]];
			}
			out += closeAnnotations( close );
		} else if ( leftPlain && !rightPlain ) {
			// [plain][formatted]
			out += openAnnotations( right[1] );
		} else if ( !leftPlain && !rightPlain ) {
			// [formatted][formatted]

			// setting index to undefined is is necessary to it does not use value from
			// the previous iteration
			open = {};
			index = undefined;

			for ( hash in left[1] ) {
				if ( !( hash in right[1] ) ) {
					index = ( index === undefined ) ?
						hashStack.indexOf( hash ) :
						Math.min( index, hashStack.indexOf( hash ) );
				}
			}

			if ( index !== undefined ) {
				close = {};
				for ( j = hashStack.length - 1; j >= index; j-- ) {
					close[hashStack[j]] = annotationStack[hashStack[j]];
				}

				for ( j = index; j < hashStack.length; j++ ) {
					if ( hashStack[j] in right[1] && hashStack[j] in left[1] ) {
						open[hashStack[j]] = annotationStack[hashStack[j]];
					}
				}
				out += closeAnnotations( close );
			}

			for ( hash in right[1] ) {
				if ( !( hash in left[1] ) ) {
					open[hash] = right[1][hash];
				}
			}

			out += openAnnotations( open );
		}

		chr = rightPlain ? right : right[0];
		out += chr in htmlChars ? htmlChars[chr] : chr;
		left = right;
	}

	close = {};
	for ( j = hashStack.length - 1; j >= 0; j-- ) {
		close[hashStack[j]] = annotationStack[hashStack[j]];
	}
	out += closeAnnotations( close );
	return out;
};

/* Registration */

ve.ce.nodeFactory.register( 'text', ve.ce.TextNode );

/* Inheritance */

ve.extendClass( ve.ce.TextNode, ve.ce.LeafNode );