/*
 * file: DTDUtil.js
 *
 * @BEGINLICENSE
 * Copyright 2010 Brook Novak  (email : brooknovak@seaweed-editor.com) 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 * @ENDLICENSE
 */


/* @DEPENDS: Util */
bootstrap.provides("DTDUtil");

/* HTML 4.01 Spec maps */
var _HTML_401_MAPS = {

    /* Generic block level */
    GB: "address,blockquote,center,del,div,h1,h2,h3,h4,h5,h6,hr,ins,isindex,noscript,p,pre",
    
    /* Special inline level */
    SI: "a,applet,basefont,bdo,br,font,iframe,img,map,area,object,param,q,script,span,sub,sup",
    
    /* Phrase level */
    PH: "abbr,acronym,cite,code,del,dfn,em,ins,kbd,samp,strong,var",
    
    /* Font level */
    F: "b,big,i,s,small,strike,tt,u",
    
    /* Table elements */
    TE: "table,caption,colgroup,col,thead,tfoot,tbody,tr,td,th",
	
	/* Form elements */
//	FE : "form,button,fieldset,legend,input,label,select,optgroup,option,textarea",
	
    /* Elements which to do support non-whitespace text as immediate children. */
    NT : "table,textarea,tr,thead,tbody,tfoot,dl,ul,ol,menu,select,optgroup,option,script,style"
};

// Build maps
for (var mem in _HTML_401_MAPS) {
    _HTML_401_MAPS[mem] = $createLookupMap(_HTML_401_MAPS[mem]);
}

$extend(_HTML_401_MAPS, {
    /* Block level */
    B: $extend($createLookupMap("dir,dl,fieldset,form,menu,noframes,ol,table,ul,dd,dt,frameset,li,tbody,td,tfoot,thead,th,tr"), _HTML_401_MAPS.GB),
    
    /* Inline level */
    I: $extend($extend($createLookupMap("abbr,acronym,cite,code,dfn,em,kbd,samp,strong,var"), _HTML_401_MAPS.F), _HTML_401_MAPS.SI)
});

/* A map of maps containing valid immediate child relationships according to HTML 4.01 transactional. */
var _HTML_401_VALIDATION_MAP = function(){

    function cloneSubset(map, exclude){
        var arr = exclude.split(","), clone = _clone(map);
        for (var i in arr) {
            delete clone[arr[i]];
        }
        return clone;
    }
    
    var BLOCKINLINEMAP = $extend(_clone(_HTML_401_MAPS.B), _HTML_401_MAPS.I);
    
    return {
    
        // Body
        body: $extend($createLookupMap("script,ins,del"), BLOCKINLINEMAP),
        
        // Generic block level
        address: $extend($createLookupMap("p"), BLOCKINLINEMAP),
        blockquote: BLOCKINLINEMAP,
        centre: BLOCKINLINEMAP,
        del: BLOCKINLINEMAP,
        h1: _HTML_401_MAPS.I,
        h2: _HTML_401_MAPS.I,
        h3: _HTML_401_MAPS.I,
        h4: _HTML_401_MAPS.I,
        h5: _HTML_401_MAPS.I,
        h6: _HTML_401_MAPS.I,
        hr: {},
        ins: BLOCKINLINEMAP,
        isindex: {},
        noscript: BLOCKINLINEMAP,
        p: _HTML_401_MAPS.I,
        pre: cloneSubset(_HTML_401_MAPS.I, "img,object,applet,big,small,sub,sup,font,basefont"),
        
        // Lists
        dir: $createLookupMap("li"),
        dl: $createLookupMap("dd,dt"),
        dt: _HTML_401_MAPS.I,
        dd: BLOCKINLINEMAP,
        li: BLOCKINLINEMAP,
        menu: $createLookupMap("li"),
        ol: $createLookupMap("li"),
        ul: $createLookupMap("li"),
        
        // Tables
        table: $createLookupMap("caption,col,colgroup,thead,tfoot,tbody"),
        caption: _HTML_401_MAPS.I,
        colgroup: $createLookupMap("col"),
        col: {},
        thead: $createLookupMap("tr"),
        tfoot: $createLookupMap("tr"),
        tbody: $createLookupMap("tr"),
        tr: $createLookupMap("td,th"),
        td: BLOCKINLINEMAP,
        th: BLOCKINLINEMAP,
        
        // Forms
        form: cloneSubset(BLOCKINLINEMAP, "form"),
        button: cloneSubset(BLOCKINLINEMAP, "a,input,select,textarea,label,button,iframe,form,isindex,fieldset"),
        fieldset: $extend($createLookupMap("legend"), BLOCKINLINEMAP),
        legend: _HTML_401_MAPS.I,
        input: {},
        label: cloneSubset(_HTML_401_MAPS.I, "label"),
        select: $createLookupMap("optgroup,option"),
        optgroup: $createLookupMap("option"),
        option: {},
        textarea: {},
        
        // Special inline elements
        a: cloneSubset(_HTML_401_MAPS.I, "a"),
        applet: $extend($createLookupMap("param"), BLOCKINLINEMAP),
        basefont: {},
        bdo: _HTML_401_MAPS.I,
        br: {},
        font: _HTML_401_MAPS.I,
        iframe: BLOCKINLINEMAP,
        img: {},
        map: $extend($createLookupMap("area"), _HTML_401_MAPS.B),
        area: {},
        object: $extend($createLookupMap("param"), BLOCKINLINEMAP),
        param: {},
        q: _HTML_401_MAPS.I,
        script: {},
        span: _HTML_401_MAPS.I,
        sub: _HTML_401_MAPS.I,
        sup: _HTML_401_MAPS.I,
        
        // Phrase level
        abbr: _HTML_401_MAPS.I,
        acroynm: _HTML_401_MAPS.I,
        cite: _HTML_401_MAPS.I,
        code: _HTML_401_MAPS.I,
        dfn: _HTML_401_MAPS.I,
        em: _HTML_401_MAPS.I,
        kbd: _HTML_401_MAPS.I,
        samp: _HTML_401_MAPS.I,
        strong: _HTML_401_MAPS.I,
        'var': _HTML_401_MAPS.I,
        
        // Font level
        b: _HTML_401_MAPS.I,
        big: _HTML_401_MAPS.I,
        i: _HTML_401_MAPS.I,
        s: _HTML_401_MAPS.I,
        small: _HTML_401_MAPS.I,
        strike: _HTML_401_MAPS.I,
        tt: _HTML_401_MAPS.I,
        u: _HTML_401_MAPS.I
    
    };
    
}();

function _isNodeAtLevel(domNode, mapName) {
    if (domNode.nodeType == Node.ELEMENT_NODE) 
        return _HTML_401_MAPS[mapName][_nodeName(domNode)] ? true : false;
    return false;
}

/**
 * Determines if an Element or Text node can be a parent of another given Element/Text/Body node.
 * Note: the contents of text nodes are not analysed, the relationship is valid for the type, but
 * if the text node contains non-whitespace symbols the relationship may not be valid.
 * 
 * Only configured for HTML 4.01 trans .. TODO: Other specs
 * 
 * @see _doesTextSupportNonWS
 * 
 * @param {Node} child The child to test
 * @param {Node} parent The parent of the child to test
 * @return {Boolean} True if child can be a child of Parent according to HTML 4.0 Transactional specification
 */
function _isValidRelationship(child, parent){
    if (child.nodeType == Node.TEXT_NODE)             
        return true;
    
    var vmap = _HTML_401_VALIDATION_MAP[_nodeName(parent)];
    if (vmap)             
        return vmap[_nodeName(child)];

    return true; // Allow any custom nodes to be added
}

/*
 * TODO: SUPPORT OF OTHER DOC TYPES.
 */

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a block level element.
 */
function _isBlockLevel(domNode) {
    return _isNodeAtLevel(domNode, "B");
}

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a block level element.
 */
function _isGenericBlockLevel(domNode) {
    return _isNodeAtLevel(domNode, "GB");
}

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a inline level element.
 */
function _isInlineLevel(domNode) {
    return _isNodeAtLevel(domNode, "I");
}

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a inline level element.
 */
function _isSpecialInlineLevel(domNode) {
    return _isNodeAtLevel(domNode, "SI");
}

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a phrase level element.
 */
function _isPhraseLevel(domNode) {
    return _isNodeAtLevel(domNode, "PH");
}

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a font level element.
 */
function _isFontLevel(domNode) {
    return _isNodeAtLevel(domNode, "F");
}

/**
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a table element. E.G. "tr", "thead" or "table" elements
 */
function _isTableElement(domNode) {
    return _isNodeAtLevel(domNode, "TE");
}

/*
 * @param {Node} domNode A dom node to test
 * @return {Boolean} True iff domNode is a form element. E.G. "input", "textarea" or "form" elements
 */
/*function _isFormElement(domNode) {
	return _isNodeAtLevel(domNode, "FE");
}*/

        
/**
 * @param {String} str A string
 * @return {Boolean} True iff str contains nothing but whitespace charactors.
 */ 
function _isAllWhiteSpace(str) {
    return /^[\t\n\r ]+$/.test(str);
}

/**
 * @param {Node} textNode A text node which has a parent node.
 * @return {Boolean} True iff the text node is allowed to contain non whitespace symbols.
 */
function _doesTextSupportNonWS(textNode){
    return !_isNodeAtLevel(textNode.parentNode, "NT");
}   

/**
 * Ready only. UTF encoding for the non breaking backspace entity (" ")'
 */
var _NBSP = _parseHTMLString(" ");

$extend(de, {
    isBlock : _isBlockLevel
});