/// <summary>
/// Used to save a page to the memory and isolated storage cache
/// </summary>
/// <param name="page"></param>
/// <param name="config"></param>
/// <returns></returns>
public async Task savePageToCachesAsync(IonPage page, IonConfig config)
{
// Memory cache
_memoryCache.savePage(page, _config);
// Local storage cache
await StorageUtils.savePageToIsolatedStorageAsync(page, config).ConfigureAwait(false);
// Save page cache index
await PageCacheIndex.save(page, _config).ConfigureAwait(false);
}
/// <summary>
/// Used to get a page with a desired identifier
/// </summary>
/// <param name="pageIdentifier"></param>
/// <returns>Already parsed IonPage</returns>
public async Task <IonPage> getPageAsync(string pageIdentifier)
{
string pageURL = PagesURLs.getPageURL(_config, pageIdentifier);
PageCacheIndex pageCacheIndex = await PageCacheIndex.retrieve(pageURL, _config).ConfigureAwait(false);
bool isNetworkConnected = NetworkUtils.isOnline();
if (pageCacheIndex == null)
{
if (isNetworkConnected)
{
IonLogging.log("Loading page \"" + pageIdentifier + "\" from server.", IonLogMessageTypes.SUCCESS);
return(await getPageFromServerAsync(pageIdentifier).ConfigureAwait(false));
}
else
{
IonLogging.log("Error getting page \"" + pageIdentifier + "\" from server or cache.", IonLogMessageTypes.ERROR);
throw new PageNotAvailableException();
}
}
// Get collection
IonCollection collection = await getCollectionAsync().ConfigureAwait(false);
// Get last changed of the page from collection
DateTime pageLastChanged = collection.getPageLastChanged(pageIdentifier);
// Estimate, if the page is outdated or not
bool isOutdated = pageCacheIndex.isOutdated(pageLastChanged);
if (!isOutdated)
{
IonLogging.log("Loading page \"" + pageIdentifier + "\" from cache.", IonLogMessageTypes.SUCCESS);
return(await getPageFromCacheAsync(pageIdentifier).ConfigureAwait(false));
}
else
{
if (isNetworkConnected)
{
// Download page from server
IonLogging.log("Loading newer version of page \"" + pageIdentifier + "\" from server.", IonLogMessageTypes.SUCCESS);
return(await getPageFromServerAsync(pageIdentifier).ConfigureAwait(false));
}
else
{
// get old version from cache
IonLogging.log("Loading potentially old version of page \"" + pageIdentifier + "\" from cache.", IonLogMessageTypes.WARNING);
return(await getPageFromCacheAsync(pageIdentifier).ConfigureAwait(false));
}
}
}
