var DeleteLine = function() {

	this.form = null;
	this.targetEx = null;

	this.delete_line = function(trg, line_id) {
		this.targetEx = trg;
		if (!this.form) {
			this.form = new Ext.form.BasicForm(this.targetEx.body, {
				errorReader: new Ext.form.XmlErrorReader(),
				waitMsgTarget: true
			});
			this.form.initEl(this.targetEx.body);
		}
		var line_tree_node = this.targetEx.getNodeById('line_' + line_id);
		if (!line_tree_node) {
			msg_error('Cannot find requested line (' + line_id + ') for deleting');
			return;
		}
		var line_text = line_tree_node.text;
		Ext.Msg.confirm('Удаление линии', 'Вы уверены, что хотите удалить линию \'' + line_text + '\'?', function(btn, text) {
			if (btn == 'yes') {
				this.form.submit({
					params: {
						line_id: line_id,
						cour_id: this.targetEx.getCourId()
					},
					method: 'POST',
					waitMsg: 'Deleting line...',
					url: 'actions/line.delete.xml.php',

					failure: function(form, action) {
						msg_error('Line was not deleted (server error). Please, reload the page and try again');
					},
					success: function(form, action) {
						line_tree_node.remove();
					},
					scope: this
				});
			}
		}, this);
	}
}