=== modified file 'dhis-2/dhis-web/dhis-web-dataentry/src/main/webapp/dhis-web-dataentry/javascript/form.js'
--- dhis-2/dhis-web/dhis-web-dataentry/src/main/webapp/dhis-web-dataentry/javascript/form.js	2011-08-29 08:32:52 +0000
+++ dhis-2/dhis-web/dhis-web-dataentry/src/main/webapp/dhis-web-dataentry/javascript/form.js	2011-08-29 19:28:09 +0000
@@ -1,1528 +1,1522 @@
-// Identifiers for which zero values are insignificant, also used in entry.js
-var significantZeros = [];
-
-// Array with associative arrays for each data element, populated in select.vm
-var dataElements = [];
-
-// Associative array with [indicator id, expression] for indicators in form,
-// also used in entry.js
-var indicatorFormulas = [];
-
-// Array with associative arrays for each data set, populated in select.vm
-var dataSets = [];
-
-// Associative array with identifier and array of assigned data sets
-var dataSetAssociationSets = [];
-
-// Associate array with mapping between organisation unit identifier and data
-// set association set identifier
-var organisationUnitAssociationSetMap = [];
-
-// Array with keys on form {dataelementid}-{optioncomboid}-min/max with min/max
-// values
-var currentMinMaxValueMap = [];
-
-// Indicates whether any data entry form has been loaded
-var dataEntryFormIsLoaded = false;
-
-// Indicates whether meta data is loaded
-var metaDataIsLoaded = false;
-
-// Currently selected organisation unit identifier
-var currentOrganisationUnitId = null;
-
-// Currently selected data set identifier
-var currentDataSetId = null;
-
-// Current offset, next or previous corresponding to increasing or decreasing
-// value with one
-var currentPeriodOffset = 0;
-
-// Period type object
-var periodTypeFactory = new PeriodType();
-
-// Instance of the StorageManager
-var storageManager = new StorageManager();
-
-var COLOR_GREEN = '#b9ffb9';
-var COLOR_YELLOW = '#fffe8c';
-var COLOR_RED = '#ff8a8a';
-var COLOR_ORANGE = '#ff6600';
-var COLOR_WHITE = '#ffffff';
-var COLOR_GREY = '#cccccc';
-
-var DEFAULT_TYPE = 'int';
-var DEFAULT_NAME = '[unknown]';
-
-var FORMTYPE_CUSTOM = 'custom';
-var FORMTYPE_SECTION = 'section';
-var FORMTYPE_DEFAULT = 'default';
-
-/**
- * Page init. The order of events is:
- * 
- * 1. Load ouwt 2. Load meta-data (and notify ouwt) 3. Check and potentially
- * download updated forms from server
- */
-$( document ).ready( function()
-{
-    $.ajaxSetup({
-        type: 'POST'
-    });
-
-    selection.setListenerFunction( organisationUnitSelected );
-    $( '#loaderSpan' ).show();
-
-    $( '#orgUnitTree' ).one( 'ouwtLoaded', function()
-    {
-        log( 'Ouwt loaded' );
-        loadMetaData();
-    } );
-
-    $( document ).bind( 'dhis2.online', function( event, loggedIn )
-	{
-	    if ( loggedIn )
-	    {
-	        if ( storageManager.hasLocalData() )
-	        {
-	            var message = i18n_need_to_sync_notification
-	            	+ ' <button id="sync_button" type="button">' + i18n_sync_now
-	            	+ '</button>';
-	
-	            setHeaderMessage( message );
-	
-	            $( '#sync_button' ).bind( 'click', uploadLocalData );
-	        }
-	        else
-	        {
-	            setHeaderDelayMessage( i18n_online_notification );
-	        }
-	    }
-	    else
-	    {
-	        setHeaderMessage( '<form style="display:inline;"><label for="username">Username</label><input name="username" id="username" type="text" size="10"/><label for="password">Password</label><input name="password" id="password" type="password" size="10"/><button id="login_button" type="button">Login</button></form>' );
-	        ajax_login();
-	    }
-	} );
-
-    $( document ).bind( 'dhis2.offline', function()
-    {
-        setHeaderMessage( i18n_offline_notification );
-    } );
-
-    dhis2.availability.startAvailabilityCheck();
-} );
-
-function ajax_login()
-{
-    $( '#login_button' ).bind( 'click', function()
-    {
-        var username = $( '#username' ).val();
-        var password = $( '#password' ).val();
-
-        $.post( '../dhis-web-commons-security/login.action', {
-            'j_username' : username,
-            'j_password' : password
-        } ).success( function()
-        {
-            var ret = dhis2.availability.syncCheckAvailability();
-
-            if ( !ret )
-            {
-                alert( i18n_ajax_login_failed );
-            }
-        } );
-    } );
-}
-
-function loadMetaData()
-{
-    var KEY_METADATA = 'metadata';
-
-    $.ajax( { 
-    	url: 'getMetaData.action',
-    	cache: false,
-    	dataType: 'json',
-    	success: function( json )
-	    {
-	        sessionStorage[KEY_METADATA] = JSON.stringify( json.metaData );
-	    },
-	    complete: function()
-	    {
-	        var metaData = JSON.parse( sessionStorage[KEY_METADATA] );
-	
-	        significantZeros = metaData.significantZeros;
-	        dataElements = metaData.dataElements;
-	        indicatorFormulas = metaData.indicatorFormulas;
-	        dataSets = metaData.dataSets;
-	        dataSetAssociationSets = metaData.dataSetAssociationSets;
-	        organisationUnitAssociationSetMap = metaData.organisationUnitAssociationSetMap;
-	
-	        metaDataIsLoaded = true;
-	        selection.responseReceived(); // Notify that meta data is loaded
-	        $( '#loaderSpan' ).hide();
-	        log( 'Meta-data loaded' );
-	
-	        updateForms();
-	    } 
-	} );
-}
-
-function uploadLocalData()
-{
-    if ( !storageManager.hasLocalData() )
-    {
-        return;
-    }
-
-    var dataValues = storageManager.getAllDataValues();
-    var completeDataSets = storageManager.getCompleteDataSets();
-
-    setHeaderWaitMessage( i18n_uploading_data_notification );
-
-    var dataValuesArray = dataValues ? Object.keys( dataValues ) : [];
-    var completeDataSetsArray = completeDataSets ? Object.keys( completeDataSets ) : [];
-
-    function pushCompleteDataSets( array )
-    {
-        if ( array.length < 1 )
-        {
-            return;
-        }
-
-        var key = array[0];
-        var value = completeDataSets[key];
-
-        log( 'Uploaded complete data set: ' + key + ', with value: ' + value );
-
-        $.ajax( {
-            url: 'registerCompleteDataSet.action',
-            data: value,
-            dataType: 'json',
-            cache: false,
-            success: function( data, textStatus, jqXHR )
-            {
-                log( 'Successfully saved complete dataset with value: ' + value );
-                storageManager.clearCompleteDataSet( value );
-                ( array = array.slice( 1 ) ).length && pushCompleteDataSets( array );
-
-                if ( array.length < 1 )
-                {
-                    setHeaderDelayMessage( i18n_sync_success );
-                }
-            },
-            error: function( jqXHR, textStatus, errorThrown )
-            {
-                var message = i18n_sync_failed
-                    + ' <button id="sync_button" type="button">' + i18n_sync_now
-                    + '</button>';
-
-                setHeaderMessage( message );
-
-                $( '#sync_button' ).bind( 'click', uploadLocalData );
-            }
-        } );
-    };
-
-    ( function pushDataValues( array )
-    {
-        if ( array.length < 1 )
-        {
-            setHeaderDelayMessage( i18n_online_notification );
-
-            pushCompleteDataSets( completeDataSetsArray );
-
-            return;
-        }
-
-        var key = array[0];
-        var value = dataValues[key];
-
-        log( 'Uploaded data value: ' + key + ', with value: ' + value );
-
-        $.ajax( {
-            url: 'saveValue.action',
-            data: value,
-            dataType: 'json',
-            cache: false,
-            success: function( data, textStatus, jqXHR )
-            {
-                storageManager.clearDataValueJSON( value );
-                log( 'Successfully saved data value with value: ' + value );
-                ( array = array.slice( 1 ) ).length && pushDataValues( array );
-
-                if ( array.length < 1 && completeDataSetsArray.length > 0 )
-                {
-                    pushCompleteDataSets( completeDataSetsArray );
-                }
-                else
-                {
-                    setHeaderDelayMessage( i18n_sync_success );
-                }
-            },
-            error: function( jqXHR, textStatus, errorThrown )
-            {
-                var message = i18n_sync_failed
-                    + ' <button id="sync_button" type="button">' + i18n_sync_now
-                    + '</button>';
-
-                setHeaderMessage( message );
-    
-                $( '#sync_button' ).bind( 'click', uploadLocalData );
-            }
-        } );
-    } )( dataValuesArray );
-}
-
-function addEventListeners()
-{	
-    var dataSetId = $( '#selectedDataSetId' ).val();
-	var formType = dataSets[dataSetId].type;
-	
-    $( '[name="entryfield"]' ).each( function( i )
-    {
-        var id = $( this ).attr( 'id' );
-        var dataElementId = id.split( '-' )[0];
-        var optionComboId = id.split( '-' )[1];
-        var type = getDataElementType( dataElementId );
-
-        $( this ).unbind( 'focus' );
-        $( this ).unbind( 'blur' );
-        $( this ).unbind( 'change' );
-        $( this ).unbind( 'dblclick' );
-        $( this ).unbind( 'keyup' );
-
-        $( this ).focus( valueFocus );
-
-        $( this ).blur( valueBlur );
-
-        $( this ).change( function()
-        {
-            saveVal( dataElementId, optionComboId );
-        } );
-
-        $( this ).dblclick( function()
-        {
-            viewHist( dataElementId, optionComboId );
-        } );
-
-        $( this ).keyup( function(event)
-        {
-            keyPress( event, this );
-        } );
-
-		if ( formType != FORMTYPE_CUSTOM )
-		{
-        	$( this ).css( 'width', '100%' );
-        	$( this ).css( 'text-align', 'center' );
-		}
-
-        if ( type == 'date' )
-        {
-            $( this ).css( 'width', '80%' );
-            datePicker( id );
-        }
-    } );
-
-    $( '[name="entryselect"]' ).each( function( i )
-    {
-        var id = $( this ).attr( 'id' );
-        var dataElementId = id.split( '-' )[0];
-        var optionComboId = id.split( '-' )[1];
-
-        $( this ).unbind( 'focus' );
-        $( this ).unbind( 'change' );
-
-        $( this ).focus( valueFocus );
-
-        $( this ).change( function()
-        {
-            saveBoolean( dataElementId, optionComboId );
-        } );
-
-        $( this ).css( 'width', '100%' );
-    } );
-}
-
-function clearPeriod()
-{
-    clearListById( 'selectedPeriodId' );
-    clearEntryForm();
-}
-
-function clearEntryForm()
-{
-    $( '#contentDiv' ).html( '' );
-
-    currentPeriodOffset = 0;
-
-    dataEntryFormIsLoaded = false;
-
-    $( '#completenessDiv' ).css( 'display', 'none' );
-}
-
-function loadForm( dataSetId )
-{
-    if ( storageManager.formExists( dataSetId ) )
-    {
-        log( 'Loading form locally: ' + dataSetId );
-
-        var html = storageManager.getForm( dataSetId );
-
-        $( '#contentDiv' ).html( html );
-
-        loadDataValues();
-    }
-    else
-    {
-        log( 'Loading form remotely: ' + dataSetId );
-
-        $( '#contentDiv' ).load( 'loadForm.action', {
-            dataSetId : dataSetId
-        }, loadDataValues );
-    }
-}
-
-function getDataElementType( dataElementId )
-{
-	if ( dataElements[dataElementId] != null )
-	{
-		return dataElements[dataElementId].type;
-	}
-	
-	log( 'Data element not present in data set, falling back to default type: ' + dataElementId );	
-	return DEFAULT_TYPE;
-}
-
-function getDataElementName( dataElementId )
-{
-	if ( dataElements[dataElementId] != null )
-	{
-		return dataElements[dataElementId].name;
-	}
-	
-	log( 'Data element present in data set, falling back to default name: ' + dataElementId );
-	return DEFAULT_NAME;	
-}
-
-// ----------------------------------------------------------------------------
-// OrganisationUnit Selection
-// -----------------------------------------------------------------------------
-
-/**
- * Returns an array containing associative array elements with id and name
- * properties. The array is sorted on the element name property.
- */
-function getSortedDataSetList()
-{
-    var associationSet = organisationUnitAssociationSetMap[currentOrganisationUnitId];
-    var orgUnitDataSets = dataSetAssociationSets[associationSet];
-
-    var dataSetList = [];
-
-    for ( i in orgUnitDataSets )
-    {
-        var dataSetId = orgUnitDataSets[i];
-        var dataSetName = dataSets[dataSetId].name;
-
-        var row = [];
-        row['id'] = dataSetId;
-        row['name'] = dataSetName;
-        dataSetList[i] = row;
-    }
-
-    dataSetList.sort( function( a, b )
-    {
-        return a.name > b.name ? 1 : a.name < b.name ? -1 : 0;
-    } );
-
-    return dataSetList;
-}
-
-function organisationUnitSelected( orgUnits, orgUnitNames )
-{
-	if ( metaDataIsLoaded == false )
-	{
-	    return false;
-	}
-	
-    currentOrganisationUnitId = orgUnits[0];
-    var organisationUnitName = orgUnitNames[0];
-
-    $( '#selectedOrganisationUnit' ).val( organisationUnitName );
-    $( '#currentOrganisationUnit' ).html( organisationUnitName );
-
-    var dataSetList = getSortedDataSetList();
-
-    $( '#selectedDataSetId' ).removeAttr( 'disabled' );
-    
-    var dataSetId = $( '#selectedDataSetId' ).val();
-    var periodId = $( '#selectedPeriodId' ).val();
-
-    clearListById( 'selectedDataSetId' );
-    addOptionById( 'selectedDataSetId', '-1', '[ ' + i18n_select_data_set + ' ]' );
-
-    var dataSetValid = false;
-
-    for ( i in dataSetList )
-    {
-        addOptionById( 'selectedDataSetId', dataSetList[i].id, dataSetList[i].name );
-
-        if ( dataSetId == dataSetList[i].id )
-        {
-            dataSetValid = true;
-        }
-    }
-
-    if ( dataSetValid && dataSetId != null )
-    {
-        $( '#selectedDataSetId' ).val( dataSetId );
-
-        if ( periodId && periodId != -1 && dataEntryFormIsLoaded )
-        {
-            showLoader();
-            loadDataValues();
-        }
-    }
-    else
-    {
-        clearPeriod();
-    }
-}
-
-// -----------------------------------------------------------------------------
-// Next/Previous Periods Selection
-// -----------------------------------------------------------------------------
-
-function nextPeriodsSelected()
-{
-    if ( currentPeriodOffset < 0 ) // Cannot display future periods
-    {
-        currentPeriodOffset++;
-        displayPeriodsInternal();
-    }
-}
-
-function previousPeriodsSelected()
-{
-    currentPeriodOffset--;
-    displayPeriodsInternal();
-}
-
-function displayPeriodsInternal()
-{
-    var dataSetId = $( '#selectedDataSetId' ).val();
-    var periodType = dataSets[dataSetId].periodType;
-    var periods = periodTypeFactory.get( periodType ).generatePeriods( currentPeriodOffset );
-    periods = periodTypeFactory.filterFuturePeriods( periods );
-
-    clearListById( 'selectedPeriodId' );
-
-    addOptionById( 'selectedPeriodId', '-1', '[ ' + i18n_select_period + ' ]' );
-
-    for ( i in periods )
-    {
-        addOptionById( 'selectedPeriodId', periods[i].id, periods[i].name );
-    }
-}
-
-// -----------------------------------------------------------------------------
-// DataSet Selection
-// -----------------------------------------------------------------------------
-
-function dataSetSelected()
-{
-    $( '#selectedPeriodId' ).removeAttr( 'disabled' );
-    $( '#prevButton' ).removeAttr( 'disabled' );
-    $( '#nextButton' ).removeAttr( 'disabled' );
-
-    var dataSetId = $( '#selectedDataSetId' ).val();
-    var periodId = $( '#selectedPeriodId' ).val();
-    var periodType = dataSets[dataSetId].periodType;
-    var periods = periodTypeFactory.get( periodType ).generatePeriods( currentPeriodOffset );
-    periods = periodTypeFactory.filterFuturePeriods( periods );
-
-    if ( dataSetId && dataSetId != -1 )
-    {
-        clearListById( 'selectedPeriodId' );
-
-        addOptionById( 'selectedPeriodId', '-1', '[ ' + i18n_select_period + ' ]' );
-
-        for ( i in periods )
-        {
-            addOptionById( 'selectedPeriodId', periods[i].id, periods[i].name );
-        }
-
-        var previousPeriodType = currentDataSetId ? dataSets[currentDataSetId].periodType : null;
-
-        if ( periodId && periodId != -1 && previousPeriodType && previousPeriodType == periodType )
-        {
-            showLoader();
-            $( '#selectedPeriodId' ).val( periodId );
-            loadForm( dataSetId );
-        }
-        else
-        {
-            clearEntryForm();
-        }
-
-        currentDataSetId = dataSetId;
-    }
-}
-
-// -----------------------------------------------------------------------------
-// Period Selection
-// -----------------------------------------------------------------------------
-
-function periodSelected()
-{
-    var periodName = $( '#selectedPeriodId :selected' ).text();
-    var dataSetId = $( '#selectedDataSetId' ).val();
-
-    $( '#currentPeriod' ).html( periodName );
-
-    var periodId = $( '#selectedPeriodId' ).val();
-
-    if ( periodId && periodId != -1 )
-    {
-        showLoader();
-
-        if ( dataEntryFormIsLoaded )
-        {
-            loadDataValues();
-        }
-        else
-        {
-            loadForm( dataSetId );
-        }
-    }
-}
-
-// -----------------------------------------------------------------------------
-// Form
-// -----------------------------------------------------------------------------
-
-function loadDataValues()
-{
-    $( '#completeButton' ).removeAttr( 'disabled' );
-    $( '#undoButton' ).attr( 'disabled', 'disabled' );
-
-    insertDataValues();
-    displayEntryFormCompleted();
-}
-
-function insertDataValues()
-{
-    var dataValueMap = [];
-	currentMinMaxValueMap = []; // Reset
-
-    var periodId = $( '#selectedPeriodId' ).val();
-    var dataSetId = $( '#selectedDataSetId' ).val();
-
-    // Clear existing values and colors, grey disabled fields
-
-    $( '[name="entryfield"]' ).val( '' );
-    $( '[name="entryselect"]' ).val( '' );
-
-    $( '[name="entryfield"]' ).css( 'background-color', COLOR_WHITE );
-    $( '[name="entryselect"]' ).css( 'background-color', COLOR_WHITE );
-
-    $( '[name="min"]' ).html( '' );
-    $( '[name="max"]' ).html( '' );
-
-    $( '[name="entryfield"]' ).filter( ':disabled' ).css( 'background-color', COLOR_GREY );
-
-    $.ajax( {
-    	url: 'getDataValues.action',
-    	data:
-	    {
-	        periodId : periodId,
-	        dataSetId : dataSetId,
-	        organisationUnitId : currentOrganisationUnitId
-	    },
-	    cache: false,
-	    dataType: 'json',
-	    success: function( json )
-	    {
-	        // Set data values, works for select lists too as data
-	        // value = select value
-	
-	        $.each( json.dataValues, function( i, value )
-	        {
-	            var fieldId = '#' + value.id + '-val';
-	
-	            if ( $( fieldId ) )
-	            {
-	                $( fieldId ).val( value.val );
-	            }
-	
-	            dataValueMap[value.id] = value.val;
-	        } );
-	
-	        // Set min-max values and colorize violation fields
-	
-	        $.each( json.minMaxDataElements, function( i, value )
-	        {
-	            var minId = value.id + '-min';
-	            var maxId = value.id + '-max';
-	
-	            var valFieldId = '#' + value.id + '-val';
-	
-	            var dataValue = dataValueMap[value.id];
-	
-	            if ( dataValue && ( ( value.min && new Number( dataValue ) < new Number( 
-	            	value.min ) ) || ( value.max && new Number( dataValue ) > new Number( value.max ) ) ) )
-	            {
-	                $( valFieldId ).css( 'background-color', COLOR_ORANGE );
-	            }
-	
-	            currentMinMaxValueMap[minId] = value.min;
-	            currentMinMaxValueMap[maxId] = value.max;
-	        } );
-	
-	        // Update indicator values in form
-	
-	        updateIndicators();
-	
-	        // Set completeness button
-	
-	        if ( json.complete )
-	        {
-	            $( '#completeButton' ).attr( 'disabled', 'disabled' );
-	            $( '#undoButton' ).removeAttr( 'disabled' );
-	        }
-	        else
-	        {
-	            $( '#completeButton' ).removeAttr( 'disabled' );
-	            $( '#undoButton' ).attr( 'disabled', 'disabled' );
-	        }
-	
-	        // TODO locking
-	    } 
-	} );
-}
-
-function displayEntryFormCompleted()
-{
-    addEventListeners();
-
-    $( '#validationButton' ).removeAttr( 'disabled' );
-    $( '#defaultForm' ).removeAttr( 'disabled' );
-
-    dataEntryFormIsLoaded = true;
-    hideLoader();
-
-    $( '#completenessDiv' ).css( 'display', 'block' );
-}
-
-function valueFocus( e )
-{
-    var id = e.target.id;
-
-    var dataElementId = id.split( '-' )[0];
-    var optionComboId = id.split( '-' )[1];
-
-    var dataElementName = getDataElementName( dataElementId );
-    var optionComboName = $( '#' + optionComboId + '-optioncombo' ).text();
-
-    $( '#currentDataElement' ).html( dataElementName + ' ' + optionComboName );
-
-    $( '#' + dataElementId + '-cell' ).addClass( 'currentRow' );
-}
-
-function valueBlur( e )
-{
-    var id = e.target.id;
-
-    var dataElementId = id.split( '-' )[0];
-
-    $( '#' + dataElementId + '-cell' ).removeClass( 'currentRow' );
-}
-
-function keyPress( event, field )
-{
-    var key = event.keyCoe || event.charCode || event.which;
-
-    var focusField = ( key == 13 || key == 40 ) ? getNextEntryField( field )
-            : ( key == 38 ) ? getPreviousEntryField( field ) : false;
-
-    if ( focusField )
-    {
-        focusField.focus();
-    }
-}
-
-function getNextEntryField( field )
-{
-    var index = field.getAttribute( 'tabindex' );
-
-    field = $( 'input[name="entryfield"][tabindex="' + ( ++index ) + '"]' );
-
-    while ( field )
-    {
-        if ( field.is( ':disabled' ) || field.is( ':hidden' ) )
-        {
-            field = $( 'input[name="entryfield"][tabindex="' + ( ++index ) + '"]' );
-        }
-        else
-        {
-            return field;
-        }
-    }
-}
-
-function getPreviousEntryField( field )
-{
-    var index = field.getAttribute( 'tabindex' );
-
-    field = $( 'input[name="entryfield"][tabindex="' + ( --index ) + '"]' );
-
-    while ( field )
-    {
-        if ( field.is( ':disabled' ) || field.is( ':hidden' ) )
-        {
-            field = $( 'input[name="entryfield"][tabindex="' + ( --index ) + '"]' );
-        }
-        else
-        {
-            return field;
-        }
-    }
-}
-
-// -----------------------------------------------------------------------------
-// Data completeness
-// -----------------------------------------------------------------------------
-
-function validateCompleteDataSet()
-{
-    var confirmed = confirm( i18n_confirm_complete );
-
-    if ( confirmed )
-    {
-        var params = storageManager.getCurrentCompleteDataSetParams();
-
-        disableCompleteButton();
-
-        $.ajax( { url: 'getValidationViolations.action',
-        	cache: false,
-        	data: params,
-        	dataType: 'json',
-        	success: function( data )
-	        {
-	            registerCompleteDataSet( data );
-	        },
-	        error: function()
-	        {
-	            // no response from server, fake a positive result and save it
-	            registerCompleteDataSet( { 'response' : 'success' } );
-	        } 
-    	} );
-    }
-}
-
-function registerCompleteDataSet( json )
-{
-    var params = storageManager.getCurrentCompleteDataSetParams();
-
-    if ( json.response == 'success' )
-    {
-        storageManager.saveCompleteDataSet( params );
-
-        $.ajax( {
-        	url: 'registerCompleteDataSet.action', 
-        	data: params, 
-        	cache: false,
-        	success: function()
-	        {
-	            storageManager.clearCompleteDataSet( params );
-	        }
-        } );
-    }
-    else
-    {
-        disableUndoButton();
-
-        validate();
-    }
-}
-
-function undoCompleteDataSet()
-{
-    var confirmed = confirm( i18n_confirm_undo );
-    var params = storageManager.getCurrentCompleteDataSetParams();
-
-    if ( confirmed )
-    {
-        disableUndoButton();
-
-        $.ajax( {
-        	url: 'undoCompleteDataSet.action', 
-        	data: params,
-        	cache: false,
-        	success: function()
-	        {
-	            storageManager.clearCompleteDataSet( params );
-	        },
-	        error: function()
-	        {
-	            storageManager.clearCompleteDataSet( params );
-	        }
-        } );
-    }
-}
-
-function disableUndoButton()
-{
-    $( '#completeButton' ).removeAttr( 'disabled' );
-    $( '#undoButton' ).attr( 'disabled', 'disabled' );
-}
-
-function disableCompleteButton()
-{
-    $( '#completeButton' ).attr( 'disabled', 'disabled' );
-    $( '#undoButton' ).removeAttr( 'disabled' );
-}
-
-// -----------------------------------------------------------------------------
-// Validation
-// -----------------------------------------------------------------------------
-
-function displayValidationDialog()
-{
-    $( '#validationDiv' ).dialog( {
-        modal : true,
-        title : 'Validation',
-        width : 800,
-        height : 400
-    } );
-}
-
-function validate()
-{
-    var periodId = $( '#selectedPeriodId' ).val();
-    var dataSetId = $( '#selectedDataSetId' ).val();
-
-    $( '#validationDiv' ).load( 'validate.action', {
-        periodId : periodId,
-        dataSetId : dataSetId,
-        organisationUnitId : currentOrganisationUnitId
-    }, function( response, status, xhr )
-    {
-        if ( status == 'error' )
-        {
-            window.alert( i18n_operation_not_available_offline );
-        }
-        else
-        {
-            displayValidationDialog();
-        }
-    } );
-}
-
-// -----------------------------------------------------------------------------
-// History
-// -----------------------------------------------------------------------------
-
-function displayHistoryDialog( operandName )
-{
-    $( '#historyDiv' ).dialog( {
-        modal : true,
-        title : operandName,
-        width : 580,
-        height : 710
-    } );
-}
-
-function viewHist( dataElementId, optionComboId )
-{
-    var periodId = $( '#selectedPeriodId' ).val();
-
-    var dataElementName = getDataElementName( dataElementId );
-    var optionComboName = $( '#' + optionComboId + '-optioncombo' ).html();
-    var operandName = dataElementName + ' ' + optionComboName;
-
-    $( '#historyDiv' ).load( 'viewHistory.action', {
-        dataElementId : dataElementId,
-        optionComboId : optionComboId,
-        periodId : periodId,
-        organisationUnitId : currentOrganisationUnitId
-    }, function( response, status, xhr )
-    {
-        if ( status == 'error' )
-        {
-            window.alert( i18n_operation_not_available_offline );
-        }
-        else
-        {
-            displayHistoryDialog( operandName );
-        }
-    } );
-}
-
-function closeCurrentSelection()
-{
-    $( '#currentSelection' ).fadeOut();
-}
-
-// -----------------------------------------------------------------------------
-// Local storage of forms
-// -----------------------------------------------------------------------------
-
-function updateForms()
-{
-    purgeLocalForms();
-    updateExistingLocalForms();
-    downloadRemoteForms();
-}
-
-function purgeLocalForms()
-{
-    var formIds = storageManager.getAllForms();
-
-    for ( i in formIds )
-    {
-        var localId = formIds[i];
-
-        if ( dataSets[localId] == null )
-        {
-            storageManager.deleteForm( localId );
-            storageManager.deleteFormVersion( localId );
-            log( 'Deleted locally stored form: ' + localId );
-        }
-    }
-
-    log( 'Purged local forms' );
-}
-
-function updateExistingLocalForms()
-{
-    var formIds = storageManager.getAllForms();
-    var formVersions = storageManager.getAllFormVersions();
-
-    for ( i in formIds )
-    {
-        var localId = formIds[i];
-
-        var remoteVersion = dataSets[localId].version;
-        var localVersion = formVersions[localId];
-
-        if ( remoteVersion == null || localVersion == null || remoteVersion != localVersion )
-        {
-            storageManager.downloadForm( localId, remoteVersion );
-        }
-    }
-}
-
-function downloadRemoteForms()
-{
-    for ( dataSetId in dataSets )
-    {
-        var remoteVersion = dataSets[dataSetId].version;
-
-        if ( !storageManager.formExists( dataSetId ) )
-        {
-            storageManager.downloadForm( dataSetId, remoteVersion );
-        }
-    }
-}
-
-// TODO break if local storage is full
-
-// -----------------------------------------------------------------------------
-// StorageManager
-// -----------------------------------------------------------------------------
-
-/**
- * This object provides utility methods for localStorage and manages data entry
- * forms and data values.
- */
-function StorageManager()
-{
-    var MAX_SIZE = new Number( 2600000 );
-    var MAX_SIZE_FORMS = new Number( 1600000 );
-
-    var KEY_FORM_PREFIX = 'form-';
-    var KEY_FORM_VERSIONS = 'formversions';
-    var KEY_DATAVALUES = 'datavalues';
-    var KEY_COMPLETEDATASETS = 'completedatasets';
-
-    /**
-     * Returns the total number of characters currently in the local storage.
-     * 
-     * @return number of characters.
-     */
-    this.totalSize = function()
-    {
-        var totalSize = new Number();
-
-        for ( var i = 0; i < localStorage.length; i++ )
-        {
-            var value = localStorage.key( i );
-
-            if ( value )
-            {
-                totalSize += value.length;
-            }
-        }
-
-        return totalSize;
-    };
-
-    /**
-     * Returns the total numbers of characters in stored forms currently in the
-     * local storage.
-     * 
-     * @return number of characters.
-     */
-    this.totalFormSize = function()
-    {
-        var totalSize = new Number();
-
-        for ( var i = 0; i < localStorage.length; i++ )
-        {
-            if ( localStorage.key( i ).substring( 0, KEY_FORM_PREFIX.length ) == KEY_FORM_PREFIX )
-            {
-                var value = localStorage.key( i );
-
-                if ( value )
-                {
-                    totalSize += value.length;
-                }
-            }
-        }
-
-        return totalSize;
-    };
-
-    /**
-     * Return the remaining capacity of the local storage in characters, ie. the
-     * maximum size minus the current size.
-     */
-    this.remainingStorage = function()
-    {
-        return MAX_SIZE - this.totalSize();
-    };
-
-    /**
-     * Saves the content of a data entry form.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     * @param html the form HTML content.
-     * @return true if the form saved successfully, false otherwise.
-     */
-    this.saveForm = function( dataSetId, html )
-    {
-        var id = KEY_FORM_PREFIX + dataSetId;
-
-        try
-        {
-            localStorage[id] = html;
-
-            log( 'Successfully stored form: ' + dataSetId );
-        } catch ( e )
-        {
-            log( 'Max local storage quota reached, ignored form: ' + dataSetId );
-            return false;
-        }
-
-        if ( MAX_SIZE_FORMS < this.totalFormSize() )
-        {
-            this.deleteForm( dataSetId );
-
-            log( 'Max local storage quota for forms reached, ignored form: ' + dataSetId );
-            return false;
-        }
-
-        return true;
-    };
-
-    /**
-     * Gets the content of a data entry form.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     * @return the content of a data entry form.
-     */
-    this.getForm = function( dataSetId )
-    {
-        var id = KEY_FORM_PREFIX + dataSetId;
-
-        return localStorage[id];
-    };
-
-    /**
-     * Removes a form.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     */
-    this.deleteForm = function( dataSetId )
-    {
-    	var id = KEY_FORM_PREFIX + dataSetId;
-    	
-        localStorage.removeItem( id );
-    };
-
-    /**
-     * Returns an array of the identifiers of all forms.
-     * 
-     * @return array with form identifiers.
-     */
-    this.getAllForms = function()
-    {
-        var formIds = [];
-
-        var formIndex = 0;
-
-        for ( var i = 0; i < localStorage.length; i++ )
-        {
-            var key = localStorage.key( i );
-
-            if ( key.substring( 0, KEY_FORM_PREFIX.length ) == KEY_FORM_PREFIX )
-            {
-                var id = key.split( '-' )[1];
-
-                formIds[formIndex++] = id;
-            }
-        }
-
-        return formIds;
-    };
-
-    /**
-     * Indicates whether a form exists.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     * @return true if a form exists, false otherwise.
-     */
-    this.formExists = function( dataSetId )
-    {
-        var id = KEY_FORM_PREFIX + dataSetId;
-
-        return localStorage[id] != null;
-    };
-
-    /**
-     * Downloads the form for the data set with the given identifier from the
-     * remote server and saves the form locally. Potential existing forms with
-     * the same identifier will be overwritten. Updates the form version.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     * @param formVersion the version of the form of the remote data set.
-     */
-    this.downloadForm = function( dataSetId, formVersion )
-    {
-        $.ajax( {
-            url: 'loadForm.action',
-            data: 
-            {
-                dataSetId : dataSetId
-            },
-            dataSetId: dataSetId,
-            formVersion: formVersion,
-            cache: false,
-            dataType: 'text',
-            success: function( data, textStatus, jqXHR )
-            {
-                storageManager.saveForm( this.dataSetId, data );
-                storageManager.saveFormVersion( this.dataSetId, this.formVersion );
-            }
-        } );
-    };
-
-    /**
-     * Saves a version for a form.
-     * 
-     * @param the identifier of the data set of the form.
-     * @param formVersion the version of the form.
-     */
-    this.saveFormVersion = function( dataSetId, formVersion )
-    {
-        var formVersions = {};
-
-        if ( localStorage[KEY_FORM_VERSIONS] != null )
-        {
-            formVersions = JSON.parse( localStorage[KEY_FORM_VERSIONS] );
-        }
-
-        formVersions[dataSetId] = formVersion;
-
-        try
-        {
-            localStorage[KEY_FORM_VERSIONS] = JSON.stringify( formVersions );
-
-            log( 'Successfully stored form version: ' + dataSetId );
-        } catch ( e )
-        {
-            log( 'Max local storage quota reached, ignored form version: ' + dataSetId );
-        }
-    };
-
-    /**
-     * Returns the version of the form of the data set with the given
-     * identifier.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     * @return the form version.
-     */
-    this.getFormVersion = function( dataSetId )
-    {
-        if ( localStorage[KEY_FORM_VERSIONS] != null )
-        {
-            var formVersions = JSON.parse( localStorage[KEY_FORM_VERSIONS] );
-
-            return formVersions[dataSetId];
-        }
-
-        return null;
-    };
-    
-    /**
-     * Deletes the form version of the data set with the given identifier.
-     * 
-     * @param dataSetId the identifier of the data set of the form.
-     */
-    this.deleteFormVersion = function( dataSetId )
-    {
-    	if ( localStorage[KEY_FORM_VERSIONS] != null )
-        {
-            var formVersions = JSON.parse( localStorage[KEY_FORM_VERSIONS] );
-
-            if ( formVersions[dataSetId] != null )
-            {
-                delete formVersions[dataSetId];
-                localStorage[KEY_FORM_VERSIONS] = JSON.stringify( formVersions );
-            }
-        }
-    }
-
-    this.getAllFormVersions = function()
-    {
-        return localStorage[KEY_FORM_VERSIONS] != null ? JSON.parse( localStorage[KEY_FORM_VERSIONS] ) : null;
-    };
-
-    /**
-     * Saves a data value.
-     * 
-     * @param dataValue The datavalue and identifiers in json format.
-     */
-    this.saveDataValue = function( dataValue )
-    {
-        var id = this.getDataValueIdentifier( dataValue.dataElementId, dataValue.optionComboId, dataValue.periodId,
-                dataValue.organisationUnitId );
-
-        var dataValues = {};
-
-        if ( localStorage[KEY_DATAVALUES] != null )
-        {
-            dataValues = JSON.parse( localStorage[KEY_DATAVALUES] );
-        }
-
-        dataValues[id] = dataValue;
-
-        try
-        {
-            localStorage[KEY_DATAVALUES] = JSON.stringify( dataValues );
-
-            log( 'Successfully stored data value' );
-        } catch ( e )
-        {
-            log( 'Max local storage quota reached, ignored data value' );
-        }
-    };
-
-    /**
-     * Gets the value for the data value with the given arguments, or null if it
-     * does not exist.
-     * 
-     * @param dataElementId the data element identifier.
-     * @param categoryOptionComboId the category option combo identifier.
-     * @param periodId the period identifier.
-     * @param organisationUnitId the organisation unit identifier.
-     * @return the value for the data value with the given arguments, null if
-     *         non-existing.
-     */
-    this.getDataValue = function( dataElementId, categoryOptionComboId, periodId, organisationUnitId )
-    {
-        var id = this.getDataValueIdentifier( dataElementId, categoryOptionComboId, periodId, organisationUnitId );
-
-        if ( localStorage[KEY_DATAVALUES] != null )
-        {
-            var dataValues = JSON.parse( localStorage[KEY_DATAVALUES] );
-
-            return dataValues[id];
-        }
-
-        return null;
-    };
-
-    /**
-     * Removes the given dataValue from localStorage.
-     * 
-     * @param dataValue The datavalue and identifiers in json format.
-     */
-    this.clearDataValueJSON = function( dataValue )
-    {
-        this.clearDataValue( dataValue.dataElementId, dataValue.optionComboId, dataValue.periodId,
-                dataValue.organisationUnitId );
-    };
-
-    /**
-     * Removes the given dataValue from localStorage.
-     * 
-     * @param dataElementId the data element identifier.
-     * @param categoryOptionComboId the category option combo identifier.
-     * @param periodId the period identifier.
-     * @param organisationUnitId the organisation unit identifier.
-     */
-    this.clearDataValue = function( dataElementId, categoryOptionComboId, periodId, organisationUnitId )
-    {
-        var id = this.getDataValueIdentifier( dataElementId, categoryOptionComboId, periodId, organisationUnitId );
-        var dataValues = this.getAllDataValues();
-
-        if ( dataValues[id] != null )
-        {
-            delete dataValues[id];
-            localStorage[KEY_DATAVALUES] = JSON.stringify( dataValues );
-        }
-    };
-
-    /**
-     * Returns a JSON associative array where the keys are on the form <data
-     * element id>-<category option combo id>-<period id>-<organisation unit
-     * id> and the data values are the values.
-     * 
-     * @return a JSON associative array.
-     */
-    this.getAllDataValues = function()
-    {
-        return localStorage[KEY_DATAVALUES] != null ? JSON.parse( localStorage[KEY_DATAVALUES] ) : null;
-    };
-
-    /**
-     * Supportive method.
-     */
-    this.getDataValueIdentifier = function( dataElementId, categoryOptionComboId, periodId, organisationUnitId )
-    {
-        return dataElementId + '-' + categoryOptionComboId + '-' + periodId + '-' + organisationUnitId;
-    };
-
-    /**
-     * Supportive method.
-     */
-    this.getCompleteDataSetId = function( json )
-    {
-        return json.periodId + '-' + json.dataSetId + '-' + json.organisationUnitId;
-    };
-
-    /**
-     * Returns current state in data entry form as associative array.
-     * 
-     * @return an associative array.
-     */
-    this.getCurrentCompleteDataSetParams = function()
-    {
-        var params = {
-            'periodId' : $( '#selectedPeriodId' ).val(),
-            'dataSetId' : $( '#selectedDataSetId' ).val(),
-            'organisationUnitId' : currentOrganisationUnitId
-        };
-
-        return params;
-    };
-
-    /**
-     * Gets all complete data set registrations as JSON.
-     * 
-     * @return all complete data set registrations as JSON.
-     */
-    this.getCompleteDataSets = function()
-    {
-        if ( localStorage[KEY_COMPLETEDATASETS] != null )
-        {
-            return JSON.parse( localStorage[KEY_COMPLETEDATASETS] );
-        }
-
-        return null;
-    };
-
-    /**
-     * Saves a complete data set registration.
-     * 
-     * @param json the complete data set registration as JSON.
-     */
-    this.saveCompleteDataSet = function( json )
-    {
-        var completeDataSets = this.getCompleteDataSets();
-        var completeDataSetId = this.getCompleteDataSetId( json );
-
-        if ( completeDataSets != null )
-        {
-            completeDataSets[completeDataSetId] = json;
-        }
-        else
-        {
-            completeDataSets = {};
-            completeDataSets[completeDataSetId] = json;
-        }
-
-        localStorage[KEY_COMPLETEDATASETS] = JSON.stringify( completeDataSets );
-    };
-
-    /**
-     * Removes the given complete data set registration.
-     * 
-     * @param the complete data set registration as JSON.
-     */
-    this.clearCompleteDataSet = function( json )
-    {
-        var completeDataSets = this.getCompleteDataSets();
-        var completeDataSetId = this.getCompleteDataSetId( json );
-
-        if ( completeDataSets != null )
-        {
-            delete completeDataSets[completeDataSetId];
-
-            if ( completeDataSets.length > 0 )
-            {
-                localStorage.remoteItem( KEY_COMPLETEDATASETS );
-            }
-            else
-            {
-                localStorage[KEY_COMPLETEDATASETS] = JSON.stringify( completeDataSets );
-            }
-        }
-    };
-
-    /**
-     * Indicators whether there exists data values or complete data set
-     * registrations in the local storage.
-     * 
-     * @return true if local data exists, false otherwise.
-     */
-    this.hasLocalData = function()
-    {
-        var dataValues = this.getAllDataValues();
-        var completeDataSets = this.getCompleteDataSets();
-
-        if ( dataValues == null && completeDataSets == null )
-        {
-            return false;
-        }
-        else if ( dataValues != null )
-        {
-            if ( Object.keys( dataValues ).length < 1 )
-            {
-                return false;
-            }
-        }
-        else if ( completeDataSets != null )
-        {
-            if ( Object.keys( completeDataSets ).length < 1 )
-            {
-                return false;
-            }
-        }
-
-        return true;
-    };
-}
+// Identifiers for which zero values are insignificant, also used in entry.js
+var significantZeros = [];
+
+// Array with associative arrays for each data element, populated in select.vm
+var dataElements = [];
+
+// Associative array with [indicator id, expression] for indicators in form,
+// also used in entry.js
+var indicatorFormulas = [];
+
+// Array with associative arrays for each data set, populated in select.vm
+var dataSets = [];
+
+// Associative array with identifier and array of assigned data sets
+var dataSetAssociationSets = [];
+
+// Associate array with mapping between organisation unit identifier and data
+// set association set identifier
+var organisationUnitAssociationSetMap = [];
+
+// Array with keys on form {dataelementid}-{optioncomboid}-min/max with min/max
+// values
+var currentMinMaxValueMap = [];
+
+// Indicates whether any data entry form has been loaded
+var dataEntryFormIsLoaded = false;
+
+// Currently selected organisation unit identifier
+var currentOrganisationUnitId = null;
+
+// Currently selected data set identifier
+var currentDataSetId = null;
+
+// Current offset, next or previous corresponding to increasing or decreasing
+// value with one
+var currentPeriodOffset = 0;
+
+// Period type object
+var periodTypeFactory = new PeriodType();
+
+// Instance of the StorageManager
+var storageManager = new StorageManager();
+
+var COLOR_GREEN = '#b9ffb9';
+var COLOR_YELLOW = '#fffe8c';
+var COLOR_RED = '#ff8a8a';
+var COLOR_ORANGE = '#ff6600';
+var COLOR_WHITE = '#ffffff';
+var COLOR_GREY = '#cccccc';
+
+var DEFAULT_TYPE = 'int';
+var DEFAULT_NAME = '[unknown]';
+
+var FORMTYPE_CUSTOM = 'custom';
+var FORMTYPE_SECTION = 'section';
+var FORMTYPE_DEFAULT = 'default';
+
+/**
+ * Page init. The order of events is:
+ * 
+ * 1. Load ouwt 2. Load meta-data (and notify ouwt) 3. Check and potentially
+ * download updated forms from server
+ */
+$( document ).ready( function()
+{
+    $.ajaxSetup({
+        type: 'POST'
+    });
+
+    selection.setListenerFunction( organisationUnitSelected );
+    $( '#loaderSpan' ).show();
+
+    $( '#orgUnitTree' ).one( 'ouwtLoaded', function()
+    {
+        log( 'Ouwt loaded' );
+        loadMetaData();
+    } );
+
+    $( document ).bind( 'dhis2.online', function( event, loggedIn )
+	{
+	    if ( loggedIn )
+	    {
+	        if ( storageManager.hasLocalData() )
+	        {
+	            var message = i18n_need_to_sync_notification
+	            	+ ' <button id="sync_button" type="button">' + i18n_sync_now
+	            	+ '</button>';
+	
+	            setHeaderMessage( message );
+	
+	            $( '#sync_button' ).bind( 'click', uploadLocalData );
+	        }
+	        else
+	        {
+	            setHeaderDelayMessage( i18n_online_notification );
+	        }
+	    }
+	    else
+	    {
+	        setHeaderMessage( '<form style="display:inline;"><label for="username">Username</label><input name="username" id="username" type="text" size="10"/><label for="password">Password</label><input name="password" id="password" type="password" size="10"/><button id="login_button" type="button">Login</button></form>' );
+	        ajax_login();
+	    }
+	} );
+
+    $( document ).bind( 'dhis2.offline', function()
+    {
+        setHeaderMessage( i18n_offline_notification );
+    } );
+
+    dhis2.availability.startAvailabilityCheck();
+} );
+
+function ajax_login()
+{
+    $( '#login_button' ).bind( 'click', function()
+    {
+        var username = $( '#username' ).val();
+        var password = $( '#password' ).val();
+
+        $.post( '../dhis-web-commons-security/login.action', {
+            'j_username' : username,
+            'j_password' : password
+        } ).success( function()
+        {
+            var ret = dhis2.availability.syncCheckAvailability();
+
+            if ( !ret )
+            {
+                alert( i18n_ajax_login_failed );
+            }
+        } );
+    } );
+}
+
+function loadMetaData()
+{
+    var KEY_METADATA = 'metadata';
+
+    $.ajax( { 
+    	url: 'getMetaData.action',
+    	cache: false,
+    	dataType: 'json',
+    	success: function( json )
+	    {
+	        sessionStorage[KEY_METADATA] = JSON.stringify( json.metaData );
+	    },
+	    complete: function()
+	    {
+	        var metaData = JSON.parse( sessionStorage[KEY_METADATA] );
+	
+	        significantZeros = metaData.significantZeros;
+	        dataElements = metaData.dataElements;
+	        indicatorFormulas = metaData.indicatorFormulas;
+	        dataSets = metaData.dataSets;
+	        dataSetAssociationSets = metaData.dataSetAssociationSets;
+	        organisationUnitAssociationSetMap = metaData.organisationUnitAssociationSetMap;
+	
+	        selection.responseReceived(); // Notify that meta data is loaded
+	        $( '#loaderSpan' ).hide();
+	        log( 'Meta-data loaded' );
+	
+	        updateForms();
+	    } 
+	} );
+}
+
+function uploadLocalData()
+{
+    if ( !storageManager.hasLocalData() )
+    {
+        return;
+    }
+
+    var dataValues = storageManager.getAllDataValues();
+    var completeDataSets = storageManager.getCompleteDataSets();
+
+    setHeaderWaitMessage( i18n_uploading_data_notification );
+
+    var dataValuesArray = dataValues ? Object.keys( dataValues ) : [];
+    var completeDataSetsArray = completeDataSets ? Object.keys( completeDataSets ) : [];
+
+    function pushCompleteDataSets( array )
+    {
+        if ( array.length < 1 )
+        {
+            return;
+        }
+
+        var key = array[0];
+        var value = completeDataSets[key];
+
+        log( 'Uploaded complete data set: ' + key + ', with value: ' + value );
+
+        $.ajax( {
+            url: 'registerCompleteDataSet.action',
+            data: value,
+            dataType: 'json',
+            cache: false,
+            success: function( data, textStatus, jqXHR )
+            {
+                log( 'Successfully saved complete dataset with value: ' + value );
+                storageManager.clearCompleteDataSet( value );
+                ( array = array.slice( 1 ) ).length && pushCompleteDataSets( array );
+
+                if ( array.length < 1 )
+                {
+                    setHeaderDelayMessage( i18n_sync_success );
+                }
+            },
+            error: function( jqXHR, textStatus, errorThrown )
+            {
+                var message = i18n_sync_failed
+                    + ' <button id="sync_button" type="button">' + i18n_sync_now
+                    + '</button>';
+
+                setHeaderMessage( message );
+
+                $( '#sync_button' ).bind( 'click', uploadLocalData );
+            }
+        } );
+    };
+
+    ( function pushDataValues( array )
+    {
+        if ( array.length < 1 )
+        {
+            setHeaderDelayMessage( i18n_online_notification );
+
+            pushCompleteDataSets( completeDataSetsArray );
+
+            return;
+        }
+
+        var key = array[0];
+        var value = dataValues[key];
+
+        log( 'Uploaded data value: ' + key + ', with value: ' + value );
+
+        $.ajax( {
+            url: 'saveValue.action',
+            data: value,
+            dataType: 'json',
+            cache: false,
+            success: function( data, textStatus, jqXHR )
+            {
+                storageManager.clearDataValueJSON( value );
+                log( 'Successfully saved data value with value: ' + value );
+                ( array = array.slice( 1 ) ).length && pushDataValues( array );
+
+                if ( array.length < 1 && completeDataSetsArray.length > 0 )
+                {
+                    pushCompleteDataSets( completeDataSetsArray );
+                }
+                else
+                {
+                    setHeaderDelayMessage( i18n_sync_success );
+                }
+            },
+            error: function( jqXHR, textStatus, errorThrown )
+            {
+                var message = i18n_sync_failed
+                    + ' <button id="sync_button" type="button">' + i18n_sync_now
+                    + '</button>';
+
+                setHeaderMessage( message );
+    
+                $( '#sync_button' ).bind( 'click', uploadLocalData );
+            }
+        } );
+    } )( dataValuesArray );
+}
+
+function addEventListeners()
+{	
+    var dataSetId = $( '#selectedDataSetId' ).val();
+	var formType = dataSets[dataSetId].type;
+	
+    $( '[name="entryfield"]' ).each( function( i )
+    {
+        var id = $( this ).attr( 'id' );
+        var dataElementId = id.split( '-' )[0];
+        var optionComboId = id.split( '-' )[1];
+        var type = getDataElementType( dataElementId );
+
+        $( this ).unbind( 'focus' );
+        $( this ).unbind( 'blur' );
+        $( this ).unbind( 'change' );
+        $( this ).unbind( 'dblclick' );
+        $( this ).unbind( 'keyup' );
+
+        $( this ).focus( valueFocus );
+
+        $( this ).blur( valueBlur );
+
+        $( this ).change( function()
+        {
+            saveVal( dataElementId, optionComboId );
+        } );
+
+        $( this ).dblclick( function()
+        {
+            viewHist( dataElementId, optionComboId );
+        } );
+
+        $( this ).keyup( function(event)
+        {
+            keyPress( event, this );
+        } );
+
+		if ( formType != FORMTYPE_CUSTOM )
+		{
+        	$( this ).css( 'width', '100%' );
+        	$( this ).css( 'text-align', 'center' );
+		}
+
+        if ( type == 'date' )
+        {
+            $( this ).css( 'width', '80%' );
+            datePicker( id );
+        }
+    } );
+
+    $( '[name="entryselect"]' ).each( function( i )
+    {
+        var id = $( this ).attr( 'id' );
+        var dataElementId = id.split( '-' )[0];
+        var optionComboId = id.split( '-' )[1];
+
+        $( this ).unbind( 'focus' );
+        $( this ).unbind( 'change' );
+
+        $( this ).focus( valueFocus );
+
+        $( this ).change( function()
+        {
+            saveBoolean( dataElementId, optionComboId );
+        } );
+
+        $( this ).css( 'width', '100%' );
+    } );
+}
+
+function clearPeriod()
+{
+    clearListById( 'selectedPeriodId' );
+    clearEntryForm();
+}
+
+function clearEntryForm()
+{
+    $( '#contentDiv' ).html( '' );
+
+    currentPeriodOffset = 0;
+
+    dataEntryFormIsLoaded = false;
+
+    $( '#completenessDiv' ).css( 'display', 'none' );
+}
+
+function loadForm( dataSetId )
+{
+    if ( storageManager.formExists( dataSetId ) )
+    {
+        log( 'Loading form locally: ' + dataSetId );
+
+        var html = storageManager.getForm( dataSetId );
+
+        $( '#contentDiv' ).html( html );
+
+        loadDataValues();
+    }
+    else
+    {
+        log( 'Loading form remotely: ' + dataSetId );
+
+        $( '#contentDiv' ).load( 'loadForm.action', {
+            dataSetId : dataSetId
+        }, loadDataValues );
+    }
+}
+
+function getDataElementType( dataElementId )
+{
+	if ( dataElements[dataElementId] != null )
+	{
+		return dataElements[dataElementId].type;
+	}
+	
+	log( 'Data element not present in data set, falling back to default type: ' + dataElementId );	
+	return DEFAULT_TYPE;
+}
+
+function getDataElementName( dataElementId )
+{
+	if ( dataElements[dataElementId] != null )
+	{
+		return dataElements[dataElementId].name;
+	}
+	
+	log( 'Data element present in data set, falling back to default name: ' + dataElementId );
+	return DEFAULT_NAME;	
+}
+
+// ----------------------------------------------------------------------------
+// OrganisationUnit Selection
+// -----------------------------------------------------------------------------
+
+/**
+ * Returns an array containing associative array elements with id and name
+ * properties. The array is sorted on the element name property.
+ */
+function getSortedDataSetList()
+{
+    var associationSet = organisationUnitAssociationSetMap[currentOrganisationUnitId];
+    var orgUnitDataSets = dataSetAssociationSets[associationSet];
+
+    var dataSetList = [];
+
+    for ( i in orgUnitDataSets )
+    {
+        var dataSetId = orgUnitDataSets[i];
+        var dataSetName = dataSets[dataSetId].name;
+
+        var row = [];
+        row['id'] = dataSetId;
+        row['name'] = dataSetName;
+        dataSetList[i] = row;
+    }
+
+    dataSetList.sort( function( a, b )
+    {
+        return a.name > b.name ? 1 : a.name < b.name ? -1 : 0;
+    } );
+
+    return dataSetList;
+}
+
+function organisationUnitSelected( orgUnits, orgUnitNames )
+{
+    currentOrganisationUnitId = orgUnits[0];
+    var organisationUnitName = orgUnitNames[0];
+
+    $( '#selectedOrganisationUnit' ).val( organisationUnitName );
+    $( '#currentOrganisationUnit' ).html( organisationUnitName );
+
+    var dataSetList = getSortedDataSetList();
+
+    if ( dataSetList.length )
+    {
+        $( '#selectedDataSetId' ).removeAttr( 'disabled' );
+        
+        var dataSetId = $( '#selectedDataSetId' ).val();
+        var periodId = $( '#selectedPeriodId' ).val();
+    
+        clearListById( 'selectedDataSetId' );
+        addOptionById( 'selectedDataSetId', '-1', '[ ' + i18n_select_data_set + ' ]' );
+
+        var dataSetValid = false;
+
+        for ( i in dataSetList )
+        {
+            addOptionById( 'selectedDataSetId', dataSetList[i].id, dataSetList[i].name );
+
+            if ( dataSetId == dataSetList[i].id )
+            {
+                dataSetValid = true;
+            }
+        }
+
+        if ( dataSetValid && dataSetId != null )
+        {
+            $( '#selectedDataSetId' ).val( dataSetId );
+
+            if ( periodId && periodId != -1 && dataEntryFormIsLoaded )
+            {
+                showLoader();
+                loadDataValues();
+            }
+        }
+        else
+        {
+            clearPeriod();
+        }
+    }
+}
+
+// -----------------------------------------------------------------------------
+// Next/Previous Periods Selection
+// -----------------------------------------------------------------------------
+
+function nextPeriodsSelected()
+{
+    if ( currentPeriodOffset < 0 ) // Cannot display future periods
+    {
+        currentPeriodOffset++;
+        displayPeriodsInternal();
+    }
+}
+
+function previousPeriodsSelected()
+{
+    currentPeriodOffset--;
+    displayPeriodsInternal();
+}
+
+function displayPeriodsInternal()
+{
+    var dataSetId = $( '#selectedDataSetId' ).val();
+    var periodType = dataSets[dataSetId].periodType;
+    var periods = periodTypeFactory.get( periodType ).generatePeriods( currentPeriodOffset );
+    periods = periodTypeFactory.filterFuturePeriods( periods );
+
+    clearListById( 'selectedPeriodId' );
+
+    addOptionById( 'selectedPeriodId', '-1', '[ ' + i18n_select_period + ' ]' );
+
+    for ( i in periods )
+    {
+        addOptionById( 'selectedPeriodId', periods[i].id, periods[i].name );
+    }
+}
+
+// -----------------------------------------------------------------------------
+// DataSet Selection
+// -----------------------------------------------------------------------------
+
+function dataSetSelected()
+{
+    $( '#selectedPeriodId' ).removeAttr( 'disabled' );
+    $( '#prevButton' ).removeAttr( 'disabled' );
+    $( '#nextButton' ).removeAttr( 'disabled' );
+
+    var dataSetId = $( '#selectedDataSetId' ).val();
+    var periodId = $( '#selectedPeriodId' ).val();
+    var periodType = dataSets[dataSetId].periodType;
+    var periods = periodTypeFactory.get( periodType ).generatePeriods( currentPeriodOffset );
+    periods = periodTypeFactory.filterFuturePeriods( periods );
+
+    if ( dataSetId && dataSetId != -1 )
+    {
+        clearListById( 'selectedPeriodId' );
+
+        addOptionById( 'selectedPeriodId', '-1', '[ ' + i18n_select_period + ' ]' );
+
+        for ( i in periods )
+        {
+            addOptionById( 'selectedPeriodId', periods[i].id, periods[i].name );
+        }
+
+        var previousPeriodType = currentDataSetId ? dataSets[currentDataSetId].periodType : null;
+
+        if ( periodId && periodId != -1 && previousPeriodType && previousPeriodType == periodType )
+        {
+            showLoader();
+            $( '#selectedPeriodId' ).val( periodId );
+            loadForm( dataSetId );
+        }
+        else
+        {
+            clearEntryForm();
+        }
+
+        currentDataSetId = dataSetId;
+    }
+}
+
+// -----------------------------------------------------------------------------
+// Period Selection
+// -----------------------------------------------------------------------------
+
+function periodSelected()
+{
+    var periodName = $( '#selectedPeriodId :selected' ).text();
+    var dataSetId = $( '#selectedDataSetId' ).val();
+
+    $( '#currentPeriod' ).html( periodName );
+
+    var periodId = $( '#selectedPeriodId' ).val();
+
+    if ( periodId && periodId != -1 )
+    {
+        showLoader();
+
+        if ( dataEntryFormIsLoaded )
+        {
+            loadDataValues();
+        }
+        else
+        {
+            loadForm( dataSetId );
+        }
+    }
+}
+
+// -----------------------------------------------------------------------------
+// Form
+// -----------------------------------------------------------------------------
+
+function loadDataValues()
+{
+    $( '#completeButton' ).removeAttr( 'disabled' );
+    $( '#undoButton' ).attr( 'disabled', 'disabled' );
+
+    insertDataValues();
+    displayEntryFormCompleted();
+}
+
+function insertDataValues()
+{
+    var dataValueMap = [];
+	currentMinMaxValueMap = []; // Reset
+
+    var periodId = $( '#selectedPeriodId' ).val();
+    var dataSetId = $( '#selectedDataSetId' ).val();
+
+    // Clear existing values and colors, grey disabled fields
+
+    $( '[name="entryfield"]' ).val( '' );
+    $( '[name="entryselect"]' ).val( '' );
+
+    $( '[name="entryfield"]' ).css( 'background-color', COLOR_WHITE );
+    $( '[name="entryselect"]' ).css( 'background-color', COLOR_WHITE );
+
+    $( '[name="min"]' ).html( '' );
+    $( '[name="max"]' ).html( '' );
+
+    $( '[name="entryfield"]' ).filter( ':disabled' ).css( 'background-color', COLOR_GREY );
+
+    $.ajax( {
+    	url: 'getDataValues.action',
+    	data:
+	    {
+	        periodId : periodId,
+	        dataSetId : dataSetId,
+	        organisationUnitId : currentOrganisationUnitId
+	    },
+	    cache: false,
+	    dataType: 'json',
+	    success: function( json )
+	    {
+	        // Set data values, works for select lists too as data
+	        // value = select value
+	
+	        $.each( json.dataValues, function( i, value )
+	        {
+	            var fieldId = '#' + value.id + '-val';
+	
+	            if ( $( fieldId ) )
+	            {
+	                $( fieldId ).val( value.val );
+	            }
+	
+	            dataValueMap[value.id] = value.val;
+	        } );
+	
+	        // Set min-max values and colorize violation fields
+	
+	        $.each( json.minMaxDataElements, function( i, value )
+	        {
+	            var minId = value.id + '-min';
+	            var maxId = value.id + '-max';
+	
+	            var valFieldId = '#' + value.id + '-val';
+	
+	            var dataValue = dataValueMap[value.id];
+	
+	            if ( dataValue && ( ( value.min && new Number( dataValue ) < new Number( 
+	            	value.min ) ) || ( value.max && new Number( dataValue ) > new Number( value.max ) ) ) )
+	            {
+	                $( valFieldId ).css( 'background-color', COLOR_ORANGE );
+	            }
+	
+	            currentMinMaxValueMap[minId] = value.min;
+	            currentMinMaxValueMap[maxId] = value.max;
+	        } );
+	
+	        // Update indicator values in form
+	
+	        updateIndicators();
+	
+	        // Set completeness button
+	
+	        if ( json.complete )
+	        {
+	            $( '#completeButton' ).attr( 'disabled', 'disabled' );
+	            $( '#undoButton' ).removeAttr( 'disabled' );
+	        }
+	        else
+	        {
+	            $( '#completeButton' ).removeAttr( 'disabled' );
+	            $( '#undoButton' ).attr( 'disabled', 'disabled' );
+	        }
+	
+	        // TODO locking
+	    } 
+	} );
+}
+
+function displayEntryFormCompleted()
+{
+    addEventListeners();
+
+    $( '#validationButton' ).removeAttr( 'disabled' );
+    $( '#defaultForm' ).removeAttr( 'disabled' );
+
+    dataEntryFormIsLoaded = true;
+    hideLoader();
+
+    $( '#completenessDiv' ).css( 'display', 'block' );
+}
+
+function valueFocus( e )
+{
+    var id = e.target.id;
+
+    var dataElementId = id.split( '-' )[0];
+    var optionComboId = id.split( '-' )[1];
+
+    var dataElementName = getDataElementName( dataElementId );
+    var optionComboName = $( '#' + optionComboId + '-optioncombo' ).text();
+
+    $( '#currentDataElement' ).html( dataElementName + ' ' + optionComboName );
+
+    $( '#' + dataElementId + '-cell' ).addClass( 'currentRow' );
+}
+
+function valueBlur( e )
+{
+    var id = e.target.id;
+
+    var dataElementId = id.split( '-' )[0];
+
+    $( '#' + dataElementId + '-cell' ).removeClass( 'currentRow' );
+}
+
+function keyPress( event, field )
+{
+    var key = event.keyCoe || event.charCode || event.which;
+
+    var focusField = ( key == 13 || key == 40 ) ? getNextEntryField( field )
+            : ( key == 38 ) ? getPreviousEntryField( field ) : false;
+
+    if ( focusField )
+    {
+        focusField.focus();
+    }
+}
+
+function getNextEntryField( field )
+{
+    var index = field.getAttribute( 'tabindex' );
+
+    field = $( 'input[name="entryfield"][tabindex="' + ( ++index ) + '"]' );
+
+    while ( field )
+    {
+        if ( field.is( ':disabled' ) || field.is( ':hidden' ) )
+        {
+            field = $( 'input[name="entryfield"][tabindex="' + ( ++index ) + '"]' );
+        }
+        else
+        {
+            return field;
+        }
+    }
+}
+
+function getPreviousEntryField( field )
+{
+    var index = field.getAttribute( 'tabindex' );
+
+    field = $( 'input[name="entryfield"][tabindex="' + ( --index ) + '"]' );
+
+    while ( field )
+    {
+        if ( field.is( ':disabled' ) || field.is( ':hidden' ) )
+        {
+            field = $( 'input[name="entryfield"][tabindex="' + ( --index ) + '"]' );
+        }
+        else
+        {
+            return field;
+        }
+    }
+}
+
+// -----------------------------------------------------------------------------
+// Data completeness
+// -----------------------------------------------------------------------------
+
+function validateCompleteDataSet()
+{
+    var confirmed = confirm( i18n_confirm_complete );
+
+    if ( confirmed )
+    {
+        var params = storageManager.getCurrentCompleteDataSetParams();
+
+        disableCompleteButton();
+
+        $.ajax( { url: 'getValidationViolations.action',
+        	cache: false,
+        	data: params,
+        	dataType: 'json',
+        	success: function( data )
+	        {
+	            registerCompleteDataSet( data );
+	        },
+	        error: function()
+	        {
+	            // no response from server, fake a positive result and save it
+	            registerCompleteDataSet( { 'response' : 'success' } );
+	        } 
+    	} );
+    }
+}
+
+function registerCompleteDataSet( json )
+{
+    var params = storageManager.getCurrentCompleteDataSetParams();
+
+    if ( json.response == 'success' )
+    {
+        storageManager.saveCompleteDataSet( params );
+
+        $.ajax( {
+        	url: 'registerCompleteDataSet.action', 
+        	data: params, 
+        	cache: false,
+        	success: function()
+	        {
+	            storageManager.clearCompleteDataSet( params );
+	        }
+        } );
+    }
+    else
+    {
+        disableUndoButton();
+
+        validate();
+    }
+}
+
+function undoCompleteDataSet()
+{
+    var confirmed = confirm( i18n_confirm_undo );
+    var params = storageManager.getCurrentCompleteDataSetParams();
+
+    if ( confirmed )
+    {
+        disableUndoButton();
+
+        $.ajax( {
+        	url: 'undoCompleteDataSet.action', 
+        	data: params,
+        	cache: false,
+        	success: function()
+	        {
+	            storageManager.clearCompleteDataSet( params );
+	        },
+	        error: function()
+	        {
+	            storageManager.clearCompleteDataSet( params );
+	        }
+        } );
+    }
+}
+
+function disableUndoButton()
+{
+    $( '#completeButton' ).removeAttr( 'disabled' );
+    $( '#undoButton' ).attr( 'disabled', 'disabled' );
+}
+
+function disableCompleteButton()
+{
+    $( '#completeButton' ).attr( 'disabled', 'disabled' );
+    $( '#undoButton' ).removeAttr( 'disabled' );
+}
+
+// -----------------------------------------------------------------------------
+// Validation
+// -----------------------------------------------------------------------------
+
+function displayValidationDialog()
+{
+    $( '#validationDiv' ).dialog( {
+        modal : true,
+        title : 'Validation',
+        width : 800,
+        height : 400
+    } );
+}
+
+function validate()
+{
+    var periodId = $( '#selectedPeriodId' ).val();
+    var dataSetId = $( '#selectedDataSetId' ).val();
+
+    $( '#validationDiv' ).load( 'validate.action', {
+        periodId : periodId,
+        dataSetId : dataSetId,
+        organisationUnitId : currentOrganisationUnitId
+    }, function( response, status, xhr )
+    {
+        if ( status == 'error' )
+        {
+            window.alert( i18n_operation_not_available_offline );
+        }
+        else
+        {
+            displayValidationDialog();
+        }
+    } );
+}
+
+// -----------------------------------------------------------------------------
+// History
+// -----------------------------------------------------------------------------
+
+function displayHistoryDialog( operandName )
+{
+    $( '#historyDiv' ).dialog( {
+        modal : true,
+        title : operandName,
+        width : 580,
+        height : 710
+    } );
+}
+
+function viewHist( dataElementId, optionComboId )
+{
+    var periodId = $( '#selectedPeriodId' ).val();
+
+    var dataElementName = getDataElementName( dataElementId );
+    var optionComboName = $( '#' + optionComboId + '-optioncombo' ).html();
+    var operandName = dataElementName + ' ' + optionComboName;
+
+    $( '#historyDiv' ).load( 'viewHistory.action', {
+        dataElementId : dataElementId,
+        optionComboId : optionComboId,
+        periodId : periodId,
+        organisationUnitId : currentOrganisationUnitId
+    }, function( response, status, xhr )
+    {
+        if ( status == 'error' )
+        {
+            window.alert( i18n_operation_not_available_offline );
+        }
+        else
+        {
+            displayHistoryDialog( operandName );
+        }
+    } );
+}
+
+function closeCurrentSelection()
+{
+    $( '#currentSelection' ).fadeOut();
+}
+
+// -----------------------------------------------------------------------------
+// Local storage of forms
+// -----------------------------------------------------------------------------
+
+function updateForms()
+{
+    purgeLocalForms();
+    updateExistingLocalForms();
+    downloadRemoteForms();
+}
+
+function purgeLocalForms()
+{
+    var formIds = storageManager.getAllForms();
+
+    for ( i in formIds )
+    {
+        var localId = formIds[i];
+
+        if ( dataSets[localId] == null )
+        {
+            storageManager.deleteForm( localId );
+            storageManager.deleteFormVersion( localId );
+            log( 'Deleted locally stored form: ' + localId );
+        }
+    }
+
+    log( 'Purged local forms' );
+}
+
+function updateExistingLocalForms()
+{
+    var formIds = storageManager.getAllForms();
+    var formVersions = storageManager.getAllFormVersions();
+
+    for ( i in formIds )
+    {
+        var localId = formIds[i];
+
+        var remoteVersion = dataSets[localId].version;
+        var localVersion = formVersions[localId];
+
+        if ( remoteVersion == null || localVersion == null || remoteVersion != localVersion )
+        {
+            storageManager.downloadForm( localId, remoteVersion );
+        }
+    }
+}
+
+function downloadRemoteForms()
+{
+    for ( dataSetId in dataSets )
+    {
+        var remoteVersion = dataSets[dataSetId].version;
+
+        if ( !storageManager.formExists( dataSetId ) )
+        {
+            storageManager.downloadForm( dataSetId, remoteVersion );
+        }
+    }
+}
+
+// TODO break if local storage is full
+
+// -----------------------------------------------------------------------------
+// StorageManager
+// -----------------------------------------------------------------------------
+
+/**
+ * This object provides utility methods for localStorage and manages data entry
+ * forms and data values.
+ */
+function StorageManager()
+{
+    var MAX_SIZE = new Number( 2600000 );
+    var MAX_SIZE_FORMS = new Number( 1600000 );
+
+    var KEY_FORM_PREFIX = 'form-';
+    var KEY_FORM_VERSIONS = 'formversions';
+    var KEY_DATAVALUES = 'datavalues';
+    var KEY_COMPLETEDATASETS = 'completedatasets';
+
+    /**
+     * Returns the total number of characters currently in the local storage.
+     * 
+     * @return number of characters.
+     */
+    this.totalSize = function()
+    {
+        var totalSize = new Number();
+
+        for ( var i = 0; i < localStorage.length; i++ )
+        {
+            var value = localStorage.key( i );
+
+            if ( value )
+            {
+                totalSize += value.length;
+            }
+        }
+
+        return totalSize;
+    };
+
+    /**
+     * Returns the total numbers of characters in stored forms currently in the
+     * local storage.
+     * 
+     * @return number of characters.
+     */
+    this.totalFormSize = function()
+    {
+        var totalSize = new Number();
+
+        for ( var i = 0; i < localStorage.length; i++ )
+        {
+            if ( localStorage.key( i ).substring( 0, KEY_FORM_PREFIX.length ) == KEY_FORM_PREFIX )
+            {
+                var value = localStorage.key( i );
+
+                if ( value )
+                {
+                    totalSize += value.length;
+                }
+            }
+        }
+
+        return totalSize;
+    };
+
+    /**
+     * Return the remaining capacity of the local storage in characters, ie. the
+     * maximum size minus the current size.
+     */
+    this.remainingStorage = function()
+    {
+        return MAX_SIZE - this.totalSize();
+    };
+
+    /**
+     * Saves the content of a data entry form.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     * @param html the form HTML content.
+     * @return true if the form saved successfully, false otherwise.
+     */
+    this.saveForm = function( dataSetId, html )
+    {
+        var id = KEY_FORM_PREFIX + dataSetId;
+
+        try
+        {
+            localStorage[id] = html;
+
+            log( 'Successfully stored form: ' + dataSetId );
+        } catch ( e )
+        {
+            log( 'Max local storage quota reached, ignored form: ' + dataSetId );
+            return false;
+        }
+
+        if ( MAX_SIZE_FORMS < this.totalFormSize() )
+        {
+            this.deleteForm( dataSetId );
+
+            log( 'Max local storage quota for forms reached, ignored form: ' + dataSetId );
+            return false;
+        }
+
+        return true;
+    };
+
+    /**
+     * Gets the content of a data entry form.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     * @return the content of a data entry form.
+     */
+    this.getForm = function( dataSetId )
+    {
+        var id = KEY_FORM_PREFIX + dataSetId;
+
+        return localStorage[id];
+    };
+
+    /**
+     * Removes a form.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     */
+    this.deleteForm = function( dataSetId )
+    {
+    	var id = KEY_FORM_PREFIX + dataSetId;
+    	
+        localStorage.removeItem( id );
+    };
+
+    /**
+     * Returns an array of the identifiers of all forms.
+     * 
+     * @return array with form identifiers.
+     */
+    this.getAllForms = function()
+    {
+        var formIds = [];
+
+        var formIndex = 0;
+
+        for ( var i = 0; i < localStorage.length; i++ )
+        {
+            var key = localStorage.key( i );
+
+            if ( key.substring( 0, KEY_FORM_PREFIX.length ) == KEY_FORM_PREFIX )
+            {
+                var id = key.split( '-' )[1];
+
+                formIds[formIndex++] = id;
+            }
+        }
+
+        return formIds;
+    };
+
+    /**
+     * Indicates whether a form exists.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     * @return true if a form exists, false otherwise.
+     */
+    this.formExists = function( dataSetId )
+    {
+        var id = KEY_FORM_PREFIX + dataSetId;
+
+        return localStorage[id] != null;
+    };
+
+    /**
+     * Downloads the form for the data set with the given identifier from the
+     * remote server and saves the form locally. Potential existing forms with
+     * the same identifier will be overwritten. Updates the form version.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     * @param formVersion the version of the form of the remote data set.
+     */
+    this.downloadForm = function( dataSetId, formVersion )
+    {
+        $.ajax( {
+            url: 'loadForm.action',
+            data: 
+            {
+                dataSetId : dataSetId
+            },
+            dataSetId: dataSetId,
+            formVersion: formVersion,
+            cache: false,
+            dataType: 'text',
+            success: function( data, textStatus, jqXHR )
+            {
+                storageManager.saveForm( this.dataSetId, data );
+                storageManager.saveFormVersion( this.dataSetId, this.formVersion );
+            }
+        } );
+    };
+
+    /**
+     * Saves a version for a form.
+     * 
+     * @param the identifier of the data set of the form.
+     * @param formVersion the version of the form.
+     */
+    this.saveFormVersion = function( dataSetId, formVersion )
+    {
+        var formVersions = {};
+
+        if ( localStorage[KEY_FORM_VERSIONS] != null )
+        {
+            formVersions = JSON.parse( localStorage[KEY_FORM_VERSIONS] );
+        }
+
+        formVersions[dataSetId] = formVersion;
+
+        try
+        {
+            localStorage[KEY_FORM_VERSIONS] = JSON.stringify( formVersions );
+
+            log( 'Successfully stored form version: ' + dataSetId );
+        } catch ( e )
+        {
+            log( 'Max local storage quota reached, ignored form version: ' + dataSetId );
+        }
+    };
+
+    /**
+     * Returns the version of the form of the data set with the given
+     * identifier.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     * @return the form version.
+     */
+    this.getFormVersion = function( dataSetId )
+    {
+        if ( localStorage[KEY_FORM_VERSIONS] != null )
+        {
+            var formVersions = JSON.parse( localStorage[KEY_FORM_VERSIONS] );
+
+            return formVersions[dataSetId];
+        }
+
+        return null;
+    };
+    
+    /**
+     * Deletes the form version of the data set with the given identifier.
+     * 
+     * @param dataSetId the identifier of the data set of the form.
+     */
+    this.deleteFormVersion = function( dataSetId )
+    {
+    	if ( localStorage[KEY_FORM_VERSIONS] != null )
+        {
+            var formVersions = JSON.parse( localStorage[KEY_FORM_VERSIONS] );
+
+            if ( formVersions[dataSetId] != null )
+            {
+                delete formVersions[dataSetId];
+                localStorage[KEY_FORM_VERSIONS] = JSON.stringify( formVersions );
+            }
+        }
+    }
+
+    this.getAllFormVersions = function()
+    {
+        return localStorage[KEY_FORM_VERSIONS] != null ? JSON.parse( localStorage[KEY_FORM_VERSIONS] ) : null;
+    };
+
+    /**
+     * Saves a data value.
+     * 
+     * @param dataValue The datavalue and identifiers in json format.
+     */
+    this.saveDataValue = function( dataValue )
+    {
+        var id = this.getDataValueIdentifier( dataValue.dataElementId, dataValue.optionComboId, dataValue.periodId,
+                dataValue.organisationUnitId );
+
+        var dataValues = {};
+
+        if ( localStorage[KEY_DATAVALUES] != null )
+        {
+            dataValues = JSON.parse( localStorage[KEY_DATAVALUES] );
+        }
+
+        dataValues[id] = dataValue;
+
+        try
+        {
+            localStorage[KEY_DATAVALUES] = JSON.stringify( dataValues );
+
+            log( 'Successfully stored data value' );
+        } catch ( e )
+        {
+            log( 'Max local storage quota reached, ignored data value' );
+        }
+    };
+
+    /**
+     * Gets the value for the data value with the given arguments, or null if it
+     * does not exist.
+     * 
+     * @param dataElementId the data element identifier.
+     * @param categoryOptionComboId the category option combo identifier.
+     * @param periodId the period identifier.
+     * @param organisationUnitId the organisation unit identifier.
+     * @return the value for the data value with the given arguments, null if
+     *         non-existing.
+     */
+    this.getDataValue = function( dataElementId, categoryOptionComboId, periodId, organisationUnitId )
+    {
+        var id = this.getDataValueIdentifier( dataElementId, categoryOptionComboId, periodId, organisationUnitId );
+
+        if ( localStorage[KEY_DATAVALUES] != null )
+        {
+            var dataValues = JSON.parse( localStorage[KEY_DATAVALUES] );
+
+            return dataValues[id];
+        }
+
+        return null;
+    };
+
+    /**
+     * Removes the given dataValue from localStorage.
+     * 
+     * @param dataValue The datavalue and identifiers in json format.
+     */
+    this.clearDataValueJSON = function( dataValue )
+    {
+        this.clearDataValue( dataValue.dataElementId, dataValue.optionComboId, dataValue.periodId,
+                dataValue.organisationUnitId );
+    };
+
+    /**
+     * Removes the given dataValue from localStorage.
+     * 
+     * @param dataElementId the data element identifier.
+     * @param categoryOptionComboId the category option combo identifier.
+     * @param periodId the period identifier.
+     * @param organisationUnitId the organisation unit identifier.
+     */
+    this.clearDataValue = function( dataElementId, categoryOptionComboId, periodId, organisationUnitId )
+    {
+        var id = this.getDataValueIdentifier( dataElementId, categoryOptionComboId, periodId, organisationUnitId );
+        var dataValues = this.getAllDataValues();
+
+        if ( dataValues[id] != null )
+        {
+            delete dataValues[id];
+            localStorage[KEY_DATAVALUES] = JSON.stringify( dataValues );
+        }
+    };
+
+    /**
+     * Returns a JSON associative array where the keys are on the form <data
+     * element id>-<category option combo id>-<period id>-<organisation unit
+     * id> and the data values are the values.
+     * 
+     * @return a JSON associative array.
+     */
+    this.getAllDataValues = function()
+    {
+        return localStorage[KEY_DATAVALUES] != null ? JSON.parse( localStorage[KEY_DATAVALUES] ) : null;
+    };
+
+    /**
+     * Supportive method.
+     */
+    this.getDataValueIdentifier = function( dataElementId, categoryOptionComboId, periodId, organisationUnitId )
+    {
+        return dataElementId + '-' + categoryOptionComboId + '-' + periodId + '-' + organisationUnitId;
+    };
+
+    /**
+     * Supportive method.
+     */
+    this.getCompleteDataSetId = function( json )
+    {
+        return json.periodId + '-' + json.dataSetId + '-' + json.organisationUnitId;
+    };
+
+    /**
+     * Returns current state in data entry form as associative array.
+     * 
+     * @return an associative array.
+     */
+    this.getCurrentCompleteDataSetParams = function()
+    {
+        var params = {
+            'periodId' : $( '#selectedPeriodId' ).val(),
+            'dataSetId' : $( '#selectedDataSetId' ).val(),
+            'organisationUnitId' : currentOrganisationUnitId
+        };
+
+        return params;
+    };
+
+    /**
+     * Gets all complete data set registrations as JSON.
+     * 
+     * @return all complete data set registrations as JSON.
+     */
+    this.getCompleteDataSets = function()
+    {
+        if ( localStorage[KEY_COMPLETEDATASETS] != null )
+        {
+            return JSON.parse( localStorage[KEY_COMPLETEDATASETS] );
+        }
+
+        return null;
+    };
+
+    /**
+     * Saves a complete data set registration.
+     * 
+     * @param json the complete data set registration as JSON.
+     */
+    this.saveCompleteDataSet = function( json )
+    {
+        var completeDataSets = this.getCompleteDataSets();
+        var completeDataSetId = this.getCompleteDataSetId( json );
+
+        if ( completeDataSets != null )
+        {
+            completeDataSets[completeDataSetId] = json;
+        }
+        else
+        {
+            completeDataSets = {};
+            completeDataSets[completeDataSetId] = json;
+        }
+
+        localStorage[KEY_COMPLETEDATASETS] = JSON.stringify( completeDataSets );
+    };
+
+    /**
+     * Removes the given complete data set registration.
+     * 
+     * @param the complete data set registration as JSON.
+     */
+    this.clearCompleteDataSet = function( json )
+    {
+        var completeDataSets = this.getCompleteDataSets();
+        var completeDataSetId = this.getCompleteDataSetId( json );
+
+        if ( completeDataSets != null )
+        {
+            delete completeDataSets[completeDataSetId];
+
+            if ( completeDataSets.length > 0 )
+            {
+                localStorage.remoteItem( KEY_COMPLETEDATASETS );
+            }
+            else
+            {
+                localStorage[KEY_COMPLETEDATASETS] = JSON.stringify( completeDataSets );
+            }
+        }
+    };
+
+    /**
+     * Indicators whether there exists data values or complete data set
+     * registrations in the local storage.
+     * 
+     * @return true if local data exists, false otherwise.
+     */
+    this.hasLocalData = function()
+    {
+        var dataValues = this.getAllDataValues();
+        var completeDataSets = this.getCompleteDataSets();
+
+        if ( dataValues == null && completeDataSets == null )
+        {
+            return false;
+        }
+        else if ( dataValues != null )
+        {
+            if ( Object.keys( dataValues ).length < 1 )
+            {
+                return false;
+            }
+        }
+        else if ( completeDataSets != null )
+        {
+            if ( Object.keys( completeDataSets ).length < 1 )
+            {
+                return false;
+            }
+        }
+
+        return true;
+    };
+}