window.AjaxUpload = function(formid)

{

	load_component(['jquery', 'jquery-ui', 'l10n']);

	var theform = document.getElementById(formid);

	theform.AjaxUpload = this;

	this.form = theform;

	$(this.form).submit(function()

		{

			return this.AjaxUpload.presubmit();

		});

};

window.zeropad = function(i, ndig)

{

	var s = String(i);

	while ( s.length < ndig )

		s = '0' + s;

	return s;

}

window.humanize_time = function(secs)

{

	var seconds = secs % 60;

	var minutes = (secs - seconds) / 60;

	if ( minutes >= 60 )

	{

		var hours = (minutes - (minutes % 60)) / 60;

		minutes = minutes % 60;

		return zeropad(hours, 2) + ':' + zeropad(minutes, 2) + ':' + zeropad(seconds, 2);

	}

	return zeropad(minutes, 2) + ':' + zeropad(seconds, 2);

}

AjaxUpload.prototype.cancelbit = false;

AjaxUpload.prototype.status = function(state)

	{

		if ( state.done )

		{

			$('div.wait-box', this.statusbox).text($lang.get('upload_msg_processing'));

			$('div.progress', this.statusbox).progressbar('value', 100);

		}

		else if ( state.cancel_upload )

		{

			if ( window.stop )

				window.stop();

			else if ( document.execCommand )

				document.execCommand('Stop');

			$('div.wait-box', this.statusbox).addClass('error-box').removeClass('wait-box').text($lang.get('upload_msg_cancelled'));

			$('div.progress', this.statusbox).progressbar('value', 100).addClass('ui-progressbar-failure');

		}

		else

		{

			var rawpct = state.bytes_processed / state.content_length;

			var pct = (Math.round((rawpct) * 1000)) / 10;

			var elapsed = state.current_time - state.start_time;

			var rawbps = state.bytes_processed / elapsed;

			var kbps = Math.round((rawbps) / 1024);

			var remain_bytes = state.content_length - state.bytes_processed;

			var remain_time = Math.round(remain_bytes / rawbps);

			if ( pct > 0 )

			$('div.wait-box', this.statusbox).text($lang.get('upload_msg_uploading', {

								percent: pct,

								elapsed: humanize_time(elapsed),

								speed: kbps,

								remain: humanize_time(remain_time)

							}))

					.append('<br /><a href="#" class="cancel"></a>');

			else

				$('div.wait-box', this.statusbox).text($lang.get('upload_msg_starting'))

					.append('<br /><a href="#" class="cancel"></a>');

			var au = this;

			$('a.cancel', this.statusbox).text($lang.get('upload_btn_cancel')).click(function()

				{

					au.cancel();

					return false;

				});

			$('div.progress', this.statusbox).progressbar('value', pct);

		}

	};

AjaxUpload.prototype.cancel = function()

	{

		this.cancelbit = true;

	};

AjaxUpload.prototype.refresh_status = function(au)

	{

		try

		{

			var cancelbit = au.cancelbit ? '&cancel=true' : '';

			au.cancelbit = false;

			ajaxGet(makeUrlNS('Special', 'AjaxUpload', 'form=' + au.form.id + '&uploadstatus=' + au.key + cancelbit), au._incoming_status);

		}

		catch (e)

		{

			alert(e);

		}

	};

AjaxUpload.prototype._incoming_status = function(ajax)

	{

		if ( ajax.readyState == 4 )

		{

			var state = parseJSON(ajax.responseText);

			if ( state )

			{

				var au = document.getElementById(state.form).AjaxUpload;

				au.status(state);

				if ( !state.done && !state.cancel_upload )

					setTimeout(function()

						{

							au.refresh_status(au)

						}, 250);

			}

		}

	};

AjaxUpload.prototype.presubmit = function()

	{

		try

		{

			// create status container and target iframe

			this.statusbox = document.createElement('div');

			this.iframe = document.createElement('iframe');

			this.iframe.AjaxUpload = this;

			$(this.iframe)

				.attr('src', 'about:blank')

				.attr('width', '1')

				.attr('height', '1')

				.attr('frameborder', '0')

				.css('visibility', 'hidden')

				.attr('name', this.form.id + '_frame')

				.load(this._frame_onload);

			this.form.parentNode.insertBefore(this.statusbox, this.form);

			this.form.parentNode.insertBefore(this.iframe, this.form);

			this.form.target = this.form.id + '_frame';

			this.upload_start();

			var have_progress_support = this.form.progress_support.value == 'true';

			if ( have_progress_support )

			{

				this.key = this.form[this.form.upload_progress_name.value].value;

				this.refresh_status(this);

			}

		}

		catch ( e )

		{

			console.debug(e);

			return false;

		}

		return true;

	};

AjaxUpload.prototype._frame_onload = function()

	{

		var childbody = window[this.AjaxUpload.form.id + '_frame'].document.getElementsByTagName('body')[0];

		window[this.AjaxUpload.form.id + '_frame'].document.close();

		this.AjaxUpload.upload_success(childbody);

	};

AjaxUpload.prototype.upload_start = function()

	{

		$(this.statusbox).html('<div class="wait-box">' + $lang.get('upload_msg_starting') + '</div><div class="progress" style="margin-top: 10px;"></div>');

		$('div.progress', this.statusbox).progressbar({ value: 0 });

		$(this.form).hide();

	};

AjaxUpload.prototype.upload_success = function(childbody)

	{

		$(this.statusbox).html('<div class="info-box">Upload complete! Result from server:' + childbody.innerHTML + '</div>');

		$('div.info-box', this.statusbox).append('<a href="#">Reset!</a>');

		var form_id = this.form.id;

		$('div.info-box a', this.statusbox).click(function()

			{

				try

				{

					var au = document.getElementById(form_id).AjaxUpload;

					au.reset();

				}

				catch(e) {};

				return false;

			});

	};

AjaxUpload.prototype.reset = function()

	{

		this.iframe.parentNode.removeChild(this.iframe);

		this.statusbox.parentNode.removeChild(this.statusbox);

		delete(window[this.form.id + '_frame']);

		$('form#' + this.form.id).show();

		return false;

	};