using System.Reactive.Linq;   // IMPORTANT - this makes await work!

// Make sure you set the application name before doing any inserts or gets
BlobCache.ApplicationName = "AkavacheExperiment";

var myToaster = new Toaster();
await BlobCache.UserAccount.InsertObject("toaster", myToaster);

//
// ...later, in another part of town...
//

// Using async/await
var toaster = await BlobCache.UserAccount.GetObject<Toaster>("toaster");

// or without async/await
Toaster toaster;

BlobCache.UserAccount.GetObject<Toaster>("toaster")
    .Subscribe(x => toaster = x, ex => Console.WriteLine("No Key!"));

Toaster toaster;

try {
    toaster = await BlobCache.UserAccount.GetObjectAsync("toaster");
} catch (KeyNotFoundException ex) {
    toaster = new Toaster();
}

// Or without async/await:
toaster = await BlobCache.UserAccount.GetObjectAsync<Toaster>("toaster")
    .Catch(Observable.Return(new Toaster()));

/*
 * Get items from the store
 */

// Get a single item
IObservable<byte[]> Get(string key);

// Get a list of items
IObservable<IDictionary<string, byte[]>> Get(IEnumerable<string> keys);

// Get an object serialized via InsertObject
IObservable<T> GetObject<T>(string key);

// Get all objects of type T
IObservable<IEnumerable<T>> GetAllObjects<T>();

// Get a list of objects given a list of keys
IObservable<IDictionary<string, T>> GetObjects<T>(IEnumerable<string> keys);

/*
 * Save items to the store
 */

// Insert a single item
IObservable<Unit> Insert(string key, byte[] data, DateTimeOffset? absoluteExpiration = null);

// Insert a set of items
IObservable<Unit> Insert(IDictionary<string, byte[]> keyValuePairs, DateTimeOffset? absoluteExpiration = null);

// Insert a single object
IObservable<Unit> InsertObject<T>(string key, T value, DateTimeOffset? absoluteExpiration = null);

// Insert a group of objects
IObservable<Unit> InsertObjects<T>(IDictionary<string, T> keyValuePairs, DateTimeOffset? absoluteExpiration = null);

/*
 * Remove items from the store
 */

// Delete a single item
IObservable<Unit> Invalidate(string key);

// Delete a list of items
IObservable<Unit> Invalidate(IEnumerable<string> keys);

// Delete a single object (do *not* use Invalidate for items inserted with InsertObject!)
IObservable<Unit> InvalidateObject<T>(string key);

// Deletes a list of objects
IObservable<Unit> InvalidateObjects<T>(IEnumerable<string> keys);

// Deletes all items (regardless if they are objects or not)
IObservable<Unit> InvalidateAll();

// Deletes all objects of type T
IObservable<Unit> InvalidateAllObjects<T>();

/*
 * Get Metadata about items
 */

// Return a list of all keys. Use for debugging purposes only.
IObservable<IEnumerable<string>> GetAllKeys();

// Return the time which an item was created
IObservable<DateTimeOffset?> GetCreatedAt(string key);

// Return the time which an object of type T was created
IObservable<DateTimeOffset?> GetObjectCreatedAt<T>(string key);

// Return the time which a list of keys were created
IObservable<IDictionary<string, DateTimeOffset?>> GetCreatedAt(IEnumerable<string> keys);

/*
 * Utility methods
 */

// Attempt to ensure all outstanding operations are written to disk
IObservable<Unit> Flush();

// Preemptively drop all expired keys and run SQLite's VACUUM method on the
// underlying database
IObservable<Unit> Vacuum();

/*
 * Username / Login Methods (only available on ISecureBlobCache)
 */

// Save login information for the given host
IObservable<Unit> SaveLogin(string user, string password, string host = "default", DateTimeOffset? absoluteExpiration = null);

// Load information for the given host
IObservable<LoginInfo> GetLoginAsync(string host = "default");

// Erase information for the given host
IObservable<Unit> EraseLogin(string host = "default");

/*
 * Downloading and caching URLs and Images
 */

// Download a file as a byte array
IObservable<byte[]> DownloadUrl(string url,
    IDictionary<string, string> headers = null,
    bool fetchAlways = false,
    DateTimeOffset? absoluteExpiration = null);

// Load a given key as an image
IObservable<IBitmap> LoadImage(string key, float? desiredWidth = null, float? desiredHeight = null);

// Download an image from the network and load it
IObservable<IBitmap> LoadImageFromUrl(string url,
    bool fetchAlways = false,
    float? desiredWidth = null,
    float? desiredHeight = null,
    DateTimeOffset? absoluteExpiration = null);

/*
 * Composite operations
 */

// Attempt to return an object from the cache. If the item doesn't
// exist or returns an error, call a Func to return the latest
// version of an object and insert the result in the cache.
IObservable<T> GetOrFetchObject<T>(string key, Func<Task<T>> fetchFunc, DateTimeOffset? absoluteExpiration = null);

// Like GetOrFetchObject, but isn't async
IObservable<T> GetOrCreateObject<T>(string key, Func<T> fetchFunc, DateTimeOffset? absoluteExpiration = null);

// Immediately return a cached version of an object if available, but *always*
// also execute fetchFunc to retrieve the latest version of an object.
IObservable<T> GetAndFetchLatest<T>(string key,
    Func<Task<T>> fetchFunc,
    Func<DateTimeOffset, bool> fetchPredicate = null,
    DateTimeOffset? absoluteExpiration = null);