/* 15.2.12.3 Extended File Properties Part */
/* [MS-OSHARED] 2.3.3.2.[1-2].1 (PIDSI/PIDDSI) */
var EXT_PROPS = [
	["Application", "Application", "string"],
	["AppVersion", "AppVersion", "string"],
	["Company", "Company", "string"],
	["DocSecurity", "DocSecurity", "string"],
	["Manager", "Manager", "string"],
	["HyperlinksChanged", "HyperlinksChanged", "bool"],
	["SharedDoc", "SharedDoc", "bool"],
	["LinksUpToDate", "LinksUpToDate", "bool"],
	["ScaleCrop", "ScaleCrop", "bool"],
	["HeadingPairs", "HeadingPairs", "raw"],
	["TitlesOfParts", "TitlesOfParts", "raw"],
];

XMLNS.EXT_PROPS = "http://schemas.openxmlformats.org/officeDocument/2006/extended-properties";
RELS.EXT_PROPS  = 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/extended-properties';

function parse_ext_props(data, p) {
	var q = {}; if(!p) p = {};

	EXT_PROPS.forEach(function(f) {
		switch(f[2]) {
			case "string": p[f[1]] = (data.match(matchtag(f[0]))||[])[1]; break;
			case "bool": p[f[1]] = (data.match(matchtag(f[0]))||[])[1] === "true"; break;
			case "raw":
				var cur = data.match(new RegExp("<" + f[0] + "[^>]*>(.*)<\/" + f[0] + ">"));
				if(cur && cur.length > 0) q[f[1]] = cur[1];
				break;
		}
	});

	if(q.HeadingPairs && q.TitlesOfParts) {
		var v = parseVector(q.HeadingPairs);
		var j = 0, widx = 0;
		for(var i = 0; i !== v.length; ++i) {
			switch(v[i].v) {
				case "Worksheets": widx = j; p.Worksheets = +(v[++i].v); break;
				case "Named Ranges": ++i; break; // TODO: Handle Named Ranges
			}
		}
		var parts = parseVector(q.TitlesOfParts).map(function(x) { return utf8read(x.v); });
		p.SheetNames = parts.slice(widx, widx + p.Worksheets);
	}
	return p;
}

var EXT_PROPS_XML_ROOT = writextag('Properties', null, {
	'xmlns': XMLNS.EXT_PROPS,
	'xmlns:vt': XMLNS.vt
});

function write_ext_props(cp, opts) {
	var o = [], p = {}, W = writextag;
	if(!cp) cp = {};
	cp.Application = "SheetJS";
	o.push(XML_HEADER);
	o.push(EXT_PROPS_XML_ROOT);

	EXT_PROPS.forEach(function(f) {
		if(typeof cp[f[1]] === 'undefined') return;
		var v;
		switch(f[2]) {
			case 'string': v = cp[f[1]]; break;
			case 'bool': v = cp[f[1]] ? 'true' : 'false'; break;
		}
		if(typeof v !== 'undefined') o.push(W(f[0], v));
	});

	/* TODO: HeadingPairs, TitlesOfParts */
	o.push(W('HeadingPairs', W('vt:vector', W('vt:variant', '<vt:lpstr>Worksheets</vt:lpstr>')+W('vt:variant', W('vt:i4', String(cp.Worksheets))), {size:2, baseType:"variant"})));
	o.push(W('TitlesOfParts', W('vt:vector', cp.SheetNames.map(function(s) { return "<vt:lpstr>" + s + "</vt:lpstr>"; }).join(""), {size: cp.Worksheets, baseType:"lpstr"})));
	if(o.length>2){ o.push('</Properties>'); o[1]=o[1].replace("/>",">"); }
	return o.join("");
}