/**
 * Export schedules of Outlook(!=express) by iCal format.
 * 
 * usage:
 *   cscript.exe ol2ics.js [/folder:folder_path] outfile.ics
 * 
 * Tried env.
 *   Outlook 2003 SP3 + XP Prof SP2(ja)
 *   Outlook 2007 SP1 + Vista Ultimate SP1 x64(ja)
 *
 * TODO:
 *   o recurring items..
 */

var exp = new ScheduleExporter();

var fn_out = "sch_export.ics";
var folder_path = null;

var args = WScript.Arguments.Unnamed;
if( args.length >= 1 )
{
	fn_out = args(0);
}

var opt = WScript.Arguments.Named;
if( opt.Item("folder") )
{
	folder_path = opt.Item("folder") ;
}
exp.export2ical( fn_out , "utf-8" , folder_path );


function ScheduleExporter()
{
	this.Manufacturer = "homemade";
	this.Name = "ScheduleExporter";

	/* Outlook - OlDefaultFolders */
	var	olFolderCalendar = 9;

	/* Outlook - OlItemType */
	var olAppointmentItem = 1;
	var olContactItem = 2;
	var olDistributionListItem = 7;
	var olJournalItem = 4;
	var olMailItem = 0;
	var olNoteItem = 5;
	var olPostItem = 6;
	var olTaskItem = 3;

	/* ADODB.Stream - SaveOptionsEnum */
	var	adSaveCreateNotExist = 1;
	var	adSaveCreateOverWrite = 2;

	/* ADODB.Stream - StreamTypeEnum */
	var	adTypeBinary = 1;
	var	adTypeText = 2;

	/* ADODB.Stream - StreamWriteEnum */
	var adWriteChar = 0;
	var	adWriteLine = 1;

	ScheduleExporter.prototype.export2ical = function( fn_out , charset , folder_path )
	{
		var app = new ActiveXObject("Outlook.Application");
		var ns = app.GetNamespace("MAPI");
	
		var folders = [];
		if( folder_path == null )
		{
			folders.push( ns.GetDefaultFolder(olFolderCalendar) );
		}
		else
		{
			folders = this.find_folder( folder_path , ns ); 
		}

		var st = new ActiveXObject("ADODB.Stream");
		st.type = adTypeText;
		st.charset = charset;
		st.open();

		st.WriteText( "BEGIN:VCALENDAR" , adWriteLine );
		st.WriteText( "METHOD:PUBLISH" , adWriteLine );
		st.WriteText( "PRODID:-//" + this.Manufacturer + "//" + this.Name + "//EN" , adWriteLine );
		st.WriteText( "VERSION:2.0" , adWriteLine );

		for( var i = 0; i < folders.length ; i++ )
		{
			this.dump_folder( folders[i] , st );
		}

		st.WriteText( "END:VCALENDAR" , adWriteLine );

		// BOM...
		var pos = 0;
		if( charset.match( /^utf-8$/i ) )
		{
			pos = 3;
		}

		st.Position = 0;
		st.Type = adTypeBinary;
		st.Position = pos;
		var bin = st.Read();
		st.Close();

		var stw = new ActiveXObject("ADODB.Stream");
		stw.Type = adTypeBinary;
		stw.Open();
		stw.Write( bin );
		stw.SaveToFile( fn_out , adSaveCreateOverWrite );
		stw.Close();

		return	true;
	}

	ScheduleExporter.prototype.find_folder = function( path , root )
	{
		var rc = [];

		var traverse = function( begin )
		{
			var folders = begin.Folders;
			
			for( var i = 1 ; i <= folders.Count ; i++ )
			{
				var folder = folders(i);
				if( folder.FolderPath && folder.FolderPath == path )
				{
					rc.push( folder );
				}
				traverse( folder );
			}
		};

		traverse( root );

		return	rc;
	}

	ScheduleExporter.prototype.dump_folder = function( folder , st )
	{
		var items = folder.Items;
		var now = new Date();
		for( var i = 1; i <= items.Count ; i++ )
		{
			var item = items(i);
	
			if( item.End >= now )
			{
				this.dump_one( item , st );
			}
		}
	}

	ScheduleExporter.prototype.dump_one = function( item , st )
	{
		var	dt_start = new Date( ""+item.Start );
		var	dt_end = new Date( ""+item.End );
		var	dt_creation = new Date( ""+item.CreationTime );

		st.WriteText( "BEGIN:VEVENT" , adWriteLine );
		if( item.AllDayEvent )
		{
			st.WriteText( "DTSTART;VALUE=DATE:" + this.by_date(dt_start) , adWriteLine );
			st.WriteText( "DTEND;VALUE=DATE:" + this.by_date(dt_end) , adWriteLine );
		}
		else
		{
			st.WriteText( "DTSTART:" + this.ical_date_utc(dt_start) , adWriteLine );
			st.WriteText( "DTEND:" + this.ical_date_utc(dt_end) , adWriteLine );
		}
		st.WriteText( "LOCATION:" + item.Location , adWriteLine );
		st.WriteText( "UID:" + item.EntryID , adWriteLine );
		st.WriteText( "DTSTAMP:" + this.ical_date_utc(dt_creation) , adWriteLine );
		st.WriteText( "SUMMARY:" + item.Subject , adWriteLine );
		// ignore item.Body. 
		// coz, It raises alert dialog to acquire permission for access secure infos.
		// so. DESCRIPTION will not be buried.
		//st.WriteText( "DESCRIPTION:" + item.Body.replace(/\r?\n/g , "\\n") , adWriteLine );
		st.WriteText( "END:VEVENT" , adWriteLine );

	}


	ScheduleExporter.prototype.zpad = function( v , n )
	{
		var s = "0000" + v;
		return	s.substr( s.length - n );
	}

	/*
	 * YYYYMMDD(Local)
	 */
	ScheduleExporter.prototype.by_date = function( dt )
	{
		var y = dt.getFullYear();
		var m = dt.getMonth()+1;
		var d = dt.getDate();

		m = this.zpad( m , 2 );
		d = this.zpad( d , 2 );

		return	y + m + d;
	}

	/*
	 * YYYYMMDDTHHMISSZ (UTC)
	 */
	ScheduleExporter.prototype.ical_date_utc = function( dt )
	{
		var y = dt.getUTCFullYear();
		var m = dt.getUTCMonth()+1;
		var d = dt.getUTCDate();
		var h = dt.getUTCHours();
		var min = dt.getUTCMinutes();
		var s = dt.getUTCSeconds();

		m = this.zpad( m , 2 );
		d = this.zpad( d , 2 );
		h = this.zpad( h , 2 );
		min = this.zpad( min , 2 );
		s = this.zpad( s , 2 );

		return	y + m + d + "T" + h + min + s + "Z";
	}

	return	this;
}