var Tokenizer = require(“./Tokenizer.js”);

/*

Options:

xmlMode: Disables the special behavior for script/style tags (false by default)
lowerCaseAttributeNames: call .toLowerCase for each attribute name (true if xmlMode is `false`)
lowerCaseTags: call .toLowerCase for each tag name (true if xmlMode is `false`)

*/

/*

Callbacks:

oncdataend,
oncdatastart,
onclosetag,
oncomment,
oncommentend,
onerror,
onopentag,
onprocessinginstruction,
onreset,
ontext

*/

var formTags = {

input: true,
option: true,
optgroup: true,
select: true,
button: true,
datalist: true,
textarea: true

};

var openImpliesClose = {

tr      : { tr:true, th:true, td:true },
th      : { th:true },
td      : { thead:true, th:true, td:true },
body    : { head:true, link:true, script:true },
li      : { li:true },
p       : { p:true },
h1      : { p:true },
h2      : { p:true },
h3      : { p:true },
h4      : { p:true },
h5      : { p:true },
h6      : { p:true },
select  : formTags,
input   : formTags,
output  : formTags,
button  : formTags,
datalist: formTags,
textarea: formTags,
option  : { option:true },
optgroup: { optgroup:true }

};

var voidElements = {

__proto__: null,
area: true,
base: true,
basefont: true,
br: true,
col: true,
command: true,
embed: true,
frame: true,
hr: true,
img: true,
input: true,
isindex: true,
keygen: true,
link: true,
meta: true,
param: true,
source: true,
track: true,
wbr: true,

//common self closing svg elements
path: true,
circle: true,
ellipse: true,
line: true,
rect: true,
use: true,
stop: true,
polyline: true,
polygon: true

};

var re_nameEnd = /s|//;

function Parser(cbs, options){

this._options = options || {};
this._cbs = cbs || {};

this._tagname = "";
this._attribname = "";
this._attribvalue = "";
this._attribs = null;
this._stack = [];

this.startIndex = 0;
this.endIndex = null;

this._lowerCaseTagNames = "lowerCaseTags" in this._options ?
                                                                !!this._options.lowerCaseTags :
                                                                !this._options.xmlMode;
this._lowerCaseAttributeNames = "lowerCaseAttributeNames" in this._options ?
                                                                !!this._options.lowerCaseAttributeNames :
                                                                !this._options.xmlMode;

if(this._options.Tokenizer) {
        Tokenizer = this._options.Tokenizer;
}
this._tokenizer = new Tokenizer(this._options, this);

if(this._cbs.onparserinit) this._cbs.onparserinit(this);

}

require(“inherits”)(Parser, require(“events”).EventEmitter);

Parser.prototype._updatePosition = function(initialOffset){

if(this.endIndex === null){
        if(this._tokenizer._sectionStart <= initialOffset){
                this.startIndex = 0;
        } else {
                this.startIndex = this._tokenizer._sectionStart - initialOffset;
        }
}
else this.startIndex = this.endIndex + 1;
this.endIndex = this._tokenizer.getAbsoluteIndex();

};

//Tokenizer event handlers Parser.prototype.ontext = function(data){

this._updatePosition(1);
this.endIndex--;

if(this._cbs.ontext) this._cbs.ontext(data);

};

Parser.prototype.onopentagname = function(name){

if(this._lowerCaseTagNames){
        name = name.toLowerCase();
}

this._tagname = name;

if(!this._options.xmlMode && name in openImpliesClose) {
        for(
                var el;
                (el = this._stack[this._stack.length - 1]) in openImpliesClose[name];
                this.onclosetag(el)
        );
}

if(this._options.xmlMode || !(name in voidElements)){
        this._stack.push(name);
}

if(this._cbs.onopentagname) this._cbs.onopentagname(name);
if(this._cbs.onopentag) this._attribs = {};

};

Parser.prototype.onopentagend = function(){

this._updatePosition(1);

if(this._attribs){
        if(this._cbs.onopentag) this._cbs.onopentag(this._tagname, this._attribs);
        this._attribs = null;
}

if(!this._options.xmlMode && this._cbs.onclosetag && this._tagname in voidElements){
        this._cbs.onclosetag(this._tagname);
}

this._tagname = "";

};

Parser.prototype.onclosetag = function(name){

this._updatePosition(1);

if(this._lowerCaseTagNames){
        name = name.toLowerCase();
}

if(this._stack.length && (!(name in voidElements) || this._options.xmlMode)){
        var pos = this._stack.lastIndexOf(name);
        if(pos !== -1){
                if(this._cbs.onclosetag){
                        pos = this._stack.length - pos;
                        while(pos--) this._cbs.onclosetag(this._stack.pop());
                }
                else this._stack.length = pos;
        } else if(name === "p" && !this._options.xmlMode){
                this.onopentagname(name);
                this._closeCurrentTag();
        }
} else if(!this._options.xmlMode && (name === "br" || name === "p")){
        this.onopentagname(name);
        this._closeCurrentTag();
}

};

Parser.prototype.onselfclosingtag = function(){

if(this._options.xmlMode || this._options.recognizeSelfClosing){
        this._closeCurrentTag();
} else {
        this.onopentagend();
}

};

Parser.prototype._closeCurrentTag = function(){

var name = this._tagname;

this.onopentagend();

//self-closing tags will be on the top of the stack
//(cheaper check than in onclosetag)
if(this._stack[this._stack.length - 1] === name){
        if(this._cbs.onclosetag){
                this._cbs.onclosetag(name);
        }
        this._stack.pop();
}

};

Parser.prototype.onattribname = function(name){

if(this._lowerCaseAttributeNames){
        name = name.toLowerCase();
}
this._attribname = name;

};

Parser.prototype.onattribdata = function(value){

this._attribvalue += value;

};

Parser.prototype.onattribend = function(){

if(this._cbs.onattribute) this._cbs.onattribute(this._attribname, this._attribvalue);
if(
        this._attribs &&
        !Object.prototype.hasOwnProperty.call(this._attribs, this._attribname)
){
        this._attribs[this._attribname] = this._attribvalue;
}
this._attribname = "";
this._attribvalue = "";

};

Parser.prototype._getInstructionName = function(value){

var idx = value.search(re_nameEnd),
    name = idx < 0 ? value : value.substr(0, idx);

if(this._lowerCaseTagNames){
        name = name.toLowerCase();
}

return name;

};

Parser.prototype.ondeclaration = function(value){

if(this._cbs.onprocessinginstruction){
        var name = this._getInstructionName(value);
        this._cbs.onprocessinginstruction("!" + name, "!" + value);
}

};

Parser.prototype.onprocessinginstruction = function(value){

if(this._cbs.onprocessinginstruction){
        var name = this._getInstructionName(value);
        this._cbs.onprocessinginstruction("?" + name, "?" + value);
}

};

Parser.prototype.oncomment = function(value){

this._updatePosition(4);

if(this._cbs.oncomment) this._cbs.oncomment(value);
if(this._cbs.oncommentend) this._cbs.oncommentend();

};

Parser.prototype.oncdata = function(value){

this._updatePosition(1);

if(this._options.xmlMode || this._options.recognizeCDATA){
        if(this._cbs.oncdatastart) this._cbs.oncdatastart();
        if(this._cbs.ontext) this._cbs.ontext(value);
        if(this._cbs.oncdataend) this._cbs.oncdataend();
} else {
        this.oncomment("[CDATA[" + value + "]]");
}

};

Parser.prototype.onerror = function(err){

if(this._cbs.onerror) this._cbs.onerror(err);

};

Parser.prototype.onend = function(){

if(this._cbs.onclosetag){
        for(
                var i = this._stack.length;
                i > 0;
                this._cbs.onclosetag(this._stack[--i])
        );
}
if(this._cbs.onend) this._cbs.onend();

};

//Resets the parser to a blank state, ready to parse a new HTML document Parser.prototype.reset = function(){

if(this._cbs.onreset) this._cbs.onreset();
this._tokenizer.reset();

this._tagname = "";
this._attribname = "";
this._attribs = null;
this._stack = [];

if(this._cbs.onparserinit) this._cbs.onparserinit(this);

};

//Parses a complete HTML document and pushes it to the handler Parser.prototype.parseComplete = function(data){

this.reset();
this.end(data);

};

Parser.prototype.write = function(chunk){

this._tokenizer.write(chunk);

};

Parser.prototype.end = function(chunk){

this._tokenizer.end(chunk);

};

Parser.prototype.pause = function(){

this._tokenizer.pause();

};

Parser.prototype.resume = function(){

this._tokenizer.resume();

};

//alias for backwards compat Parser.prototype.parseChunk = Parser.prototype.write; Parser.prototype.done = Parser.prototype.end;

module.exports = Parser;