/* EventCalendar. Copyright (C) 2005-2007, Alex Tingle.  $Revision: 284 $

 * This file is licensed under the GNU GPL. See LICENSE file for details.

 */

// Set in HTML file:

//   var ec3.start_of_week

//   var ec3.month_of_year

//   var ec3.month_abbrev

//   var ec3.myfiles

//   var ec3.home

//   var ec3.hide_logo

//   var ec3.viewpostsfor

/** Register an onload function. */

function WindowOnload(f)

{

  var prev=window.onload;

  window.onload=function(){ if(prev)prev(); f(); }

}

// namespace

function ec3()

{

  WindowOnload( function()

  {

    // Overwrite the href links in ec3_prev & ec3_next to activate EC3.

    var prev=document.getElementById('ec3_prev');

    var next=document.getElementById('ec3_next');

    if(prev && next)

    {

      // Check for cat limit in month link

      var xCat=new RegExp('&cat=[0-9]+$');

      var match=xCat.exec(prev.href);

      if(match)

        ec3.catClause=match[0];

      // Replace links

      prev.href='javascript:ec3.go_prev()';

      next.href='javascript:ec3.go_next()';

      // Pre-load image.

      ec3.imgwait=new Image(14,14);

      ec3.imgwait.src=ec3.myfiles+'/ec_load.gif';

      // Convert strings from PHP into Unicode

      ec3.viewpostsfor=unencode(ec3.viewpostsfor);

      for(var i=0; i<ec3.month_of_year.length; i++)

        ec3.month_of_year[i]=unencode(ec3.month_of_year[i]);

      for(var j=0; j<ec3.month_abbrev.length; j++)

        ec3.month_abbrev[j]=unencode(ec3.month_abbrev[j]);

    }

  } );

  /** Converts HTML encoded text (e.g. "&copy Copyright") into Unicode. */

  function unencode(text)

  {

    if(!ec3.unencodeDiv)

      ec3.unencodeDiv=document.createElement('div');

    ec3.unencodeDiv.innerHTML=text;

    return (ec3.unencodeDiv.innerText || ec3.unencodeDiv.firstChild.nodeValue);

  }

  function get_child_by_tag_name(element,tag_name)

  {

    var results=element.getElementsByTagName(tag_name);

    if(results)

      for(var i=0; i<results.length; i++)

        if(results[i].parentNode==element)

          return results[i];

    return 0;

  }

  ec3.get_child_by_tag_name=get_child_by_tag_name;

  function calc_day_id(day_num,month_num,year_num)

  {

    if(ec3.today_day_num==day_num &&

       ec3.today_month_num==month_num &&

       ec3.today_year_num==year_num)

    {

      return 'today';

    }

    else

    {

      return 'ec3_'+year_num+'_'+month_num+'_'+day_num;

    }

  }

  /** Replaces the caption and tbody in table to be the specified year/month. */

  function create_calendar(table_cal,month_num,year_num)

  {

    // Take a deep copy of the current calendar.

    var table=table_cal.cloneNode(1);

    // Calculate the zero-based month_num

    var month_num0=month_num-1;

    // Set the new caption

    var caption=get_child_by_tag_name(table,'caption');

    if(caption)

    {

      var c=get_child_by_tag_name(caption,'a');

      var caption_text=ec3.month_of_year[month_num0] + ' ' + year_num;

      if(c && c.firstChild && c.firstChild.nodeType==ec3.TEXT_NODE )

      {

	if(month_num<10) 

	{

	  c.href=ec3.home+'/?m='+year_num+'0'+month_num;

	}

	else

	{

	  c.href=ec3.home+'/?m='+year_num+month_num;

	}

        if(ec3.catClause)

           c.href+=ec3.catClause; // Copy cat' limit from original month link.

        c.title=ec3.viewpostsfor;

        c.title=c.title.replace(/%1\$s/,ec3.month_of_year[month_num0]);

        c.title=c.title.replace(/%2\$s/,year_num);

        c.firstChild.data=caption_text;

      }

    }

    if(caption && caption.firstChild && caption.firstChild.nodeType==ec3.TEXT_NODE)

      caption.firstChild.data=ec3.month_of_year[month_num0] + ' ' + year_num;

    var tbody=get_child_by_tag_name(table,'tbody');

    // Remove all children from the table body

    while(tbody.lastChild)

      tbody.removeChild(tbody.lastChild);

    // Make a new calendar.

    var date=new Date(year_num,month_num0,1, 12,00,00);

    var tr=document.createElement('tr');

    var td,div;

    tbody.appendChild(tr);

    var day_count=0

    var col=0;

    while(date.getMonth()==month_num0 && day_count<40)

    {

      var day=(date.getDay()+7-ec3.start_of_week)%7;

      if(col>6)

      {

        tr=document.createElement('tr');

        tbody.appendChild(tr);

        col=0;

      }

      if(col<day)

      {

        // insert padding

        td=document.createElement('td');

        td.colSpan=day-col;

        td.className='pad';

        tr.appendChild(td);

        col=day;

      }

      // insert day

      td=document.createElement('td');

      td.appendChild(document.createTextNode(date.getDate()));

      td.id=calc_day_id(date.getDate(),month_num,year_num);

      tr.appendChild(td);

      col++;

      day_count++;

      date.setDate(date.getDate()+1);

    }

    // insert padding

    if(col<7)

    {

      td=document.createElement('td');

      td.colSpan=7-col;

      td.className='pad';

      tr.appendChild(td);

    }

    // add the 'dog'

    if((7-col)>1 && !ec3.hide_logo)

    {

      a=document.createElement('a');

      a.href='http://blog.firetree.net/?ec3_version='+ec3.version;

      a.title='Event Calendar '+ec3.version;

      td.style.verticalAlign='bottom';

      td.appendChild(a);

      div=document.createElement('div');

      div.className='ec3_ec';

      div.align='right'; // keeps IE happy

      a.appendChild(div);

    }

    // set table's element id

    table.id='ec3_'+year_num+'_'+month_num;

    return table;

  } // end create_calendar()

  /** Dispatch an XMLHttpRequest for a month of calendar entries. */

  function loadDates(month_num,year_num)

  {

    var req=new XMLHttpRequest();

    if(req)

    {

      ec3.reqs.push(req);

      req.onreadystatechange=process_xml;

      req.open("GET",

        ec3.home+'/?ec3_xml='+year_num+'_'+month_num,true);

      set_spinner(1);

      req.send(null);

    }

  }

  /** Obtain an array of all the calendar tables. */

  function get_calendars()

  {

    var div=document.getElementById('wp-calendar');

    var result=new Array();

    for(var i=0; i<div.childNodes.length; i++)

    {

      var c=div.childNodes[i];

      if(c.id && c.id.search('ec3_[0-9]')==0 && c.style.display!='none')

        result.push(div.childNodes[i]);

    }

    if(result.length>0)

      return result;

    else

      return 0;

  }

  ec3.get_calendars=get_calendars;

  /** Changes the link text in the forward and backwards buttons.

   *  Parameters are the 0-based month numbers. */

  function rewrite_controls(prev_month0,next_month0)

  {

    var prev=document.getElementById('ec3_prev');

    if(prev && prev.firstChild && prev.firstChild.nodeType==ec3.TEXT_NODE)

      prev.firstChild.data='\u00ab\u00a0'+ec3.month_abbrev[prev_month0%12];

    var next=document.getElementById('ec3_next');

    if(next && next.firstChild && next.firstChild.nodeType==ec3.TEXT_NODE)

      next.firstChild.data=ec3.month_abbrev[next_month0%12]+'\u00a0\u00bb';

  }

  /** Turn the busy spinner on or off. */

  function set_spinner(on)

  {

    var spinner=document.getElementById('ec3_spinner');

    var publish=document.getElementById('ec3_publish');

    if(spinner)

    {

      if(on)

      {

        spinner.style.display='inline';

        if(publish)

          publish.style.display='none';

      }

      else

      {

        spinner.style.display='none';

        if(publish)

          publish.style.display='inline';

      }

    }

  }

  /** Called when the user clicks the 'previous month' button. */

  function go_prev()

  {

    var calendars=get_calendars();

    if(!calendars)

      return;

    var pn=calendars[0].parentNode;

    // calculate date of new calendar

    var id_array=calendars[0].id.split('_');

    if(id_array.length<3)

      return;

    var year_num=parseInt(id_array[1]);

    var month_num=parseInt(id_array[2])-1;

    if(month_num==0)

    {

      month_num=12;

      year_num--;

    }

    // Get new calendar

    var newcal=document.getElementById('ec3_'+year_num+'_'+month_num);

    if(newcal)

    {

      // Add in the new first calendar

      newcal.style.display=ec3.calendar_display;

    }

    else

    {

      newcal=create_calendar(calendars[0],month_num,year_num);

      pn.insertBefore( newcal, calendars[0] );

      loadDates(month_num,year_num);

    }

    // Hide the last calendar

    ec3.calendar_display=calendars[calendars.length-1].style.display;

    calendars[calendars.length-1].style.display='none';

    // Re-write the forward & back buttons.

    rewrite_controls(month_num+10,month_num+calendars.length-1);

  }

  ec3.go_prev=go_prev;

  /** Called when the user clicks the 'next month' button. */

  function go_next()

  {

    var calendars=get_calendars();

    if(!calendars)

      return;

    var pn=calendars[0].parentNode;

    var last_cal=calendars[calendars.length-1];

    // calculate date of new calendar

    var id_array=last_cal.id.split('_');

    if(id_array.length<3)

      return;

    var year_num=parseInt(id_array[1]);

    var month_num=1+parseInt(id_array[2]);

    if(month_num==13)

    {

      month_num=1;

      year_num++;

    }

    // Get new calendar

    var newcal=document.getElementById('ec3_'+year_num+'_'+month_num);

    if(newcal)

    {

      // Add in the new last calendar

      newcal.style.display=ec3.calendar_display;

    }

    else

    {

      newcal=create_calendar(calendars[0],month_num,year_num);

      if(last_cal.nextSibling)

        pn.insertBefore(newcal,last_cal.nextSibling);

      else

        pn.appendChild(newcal);

      loadDates(month_num,year_num);

    }

    // Hide the first calendar

    ec3.calendar_display=calendars[0].style.display;

    calendars[0].style.display='none';

    // Re-write the forward & back buttons.

    rewrite_controls(month_num-calendars.length+11,month_num);

  }

  ec3.go_next=go_next;

  /** Triggered when the XML load is complete. Checks that load is OK, and then

   *  updates calendar days. */

  function process_xml()

  {

    var busy=0;

    for(var i=0; i<ec3.reqs.length; i++)

    {

      var req=ec3.reqs[i];

      if(req)

      {

        if(req.readyState==4)

        {

          ec3.reqs[i]=0;

          if(req.status==200)

            update_days(req.responseXML.documentElement);

        }

        else

          busy=1;

      }

    }

    if(!busy)

    {