// ------------------------------------------------------------------------------
// Copyright 2014 Microsoft Corporation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ------------------------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.ApplicationModel;
using Windows.ApplicationModel.Activation;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.Phone.UI.Input;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Microsoft.Live;

// The Blank Application template is documented at http://go.microsoft.com/fwlink/?LinkId=234227

namespace LiveSDKPhoneRTSample
{
    /// <summary>
    /// Provides application-specific behavior to supplement the default Application class.
    /// </summary>
    sealed partial class App : Application
    {
        /// <summary>
        /// Initializes the singleton application object.  This is the first line of authored code
        /// executed, and as such is the logical equivalent of main() or WinMain().
        /// </summary>
        public App()
        {
            this.InitializeComponent();
            this.Suspending += OnSuspending;
            HardwareButtons.BackPressed += HardwareButtons_BackPressed;
        }

        /// <summary>
        /// Handles back button press.  If app is at the root page of app, don't go back and the
        /// system will suspend the app.
        /// </summary>
        /// <param name="sender">The source of the BackPressed event.</param>
        /// <param name="e">Details for the BackPressed event.</param>
        private void HardwareButtons_BackPressed(object sender, BackPressedEventArgs e)
        {
            Frame frame = Window.Current.Content as Frame;
            if (frame == null)
            {
                return;
            }

            if (frame.CanGoBack)
            {
                frame.GoBack();
                e.Handled = true;
            }
        }

        /// <summary>
        /// Invoked when the application is launched normally by the end user.  Other entry points
        /// will be used when the application is launched to open a specific file, to display
        /// search results, and so forth.
        /// </summary>
        /// <param name="e">Details about the launch request and process.</param>
        protected override void OnLaunched(LaunchActivatedEventArgs e)
        {

#if DEBUG
            if (System.Diagnostics.Debugger.IsAttached)
            {
                this.DebugSettings.EnableFrameRateCounter = true;
            }
#endif
            Frame rootFrame = Window.Current.Content as Frame;

            // Do not repeat app initialization when the Window already has content,
            // just ensure that the window is active
            if (rootFrame == null)
            {
                // Create a Frame to act as the navigation context and navigate to the first page
                rootFrame = new Frame();

                // Set the default language
                rootFrame.Language = Windows.Globalization.ApplicationLanguages.Languages[0];

                rootFrame.NavigationFailed += OnNavigationFailed;

                if (e.PreviousExecutionState == ApplicationExecutionState.Terminated)
                {
                    //TODO: Load state from previously suspended application
                }

                // Place the frame in the current Window
                Window.Current.Content = rootFrame;
            }

            if (rootFrame.Content == null)
            {
                // When the navigation stack isn't restored navigate to the first page,
                // configuring the new page by passing required information as a navigation
                // parameter
                rootFrame.Navigate(typeof(MainPage), e.Arguments);
            }
            // Ensure the current window is active
            Window.Current.Activate();

            ProcessPendingBackgroundOperations();
        }

        private async void ProcessPendingBackgroundOperations()
        {
            try
            {
                var pendingDownloadOperations = await LiveConnectClient.GetCurrentBackgroundDownloadsAsync();
                foreach (LiveDownloadOperation pendingOperation in pendingDownloadOperations)
                {
                    try
                    {
                        var opResult = await pendingOperation.AttachAsync();
                        // handle results
                    }
                    catch (Exception)
                    {
                        // handle errors
                    }
                }

                var pendingUploadOperations = await LiveConnectClient.GetCurrentBackgroundUploadsAsync();
                foreach (LiveUploadOperation pendingOperation in pendingUploadOperations)
                {
                    try
                    {
                        var opResult = await pendingOperation.AttachAsync();
                        // handle results
                    }
                    catch (Exception)
                    {
                        // handle errors
                    }
                }
            }
            catch(Exception)
            {
                // Handle errors
            }
        }

        /// <summary>
        /// Invoked when Navigation to a certain page fails.
        /// </summary>
        /// <param name="sender">The Frame which failed navigation.</param>
        /// <param name="e">Details about the navigation failure.</param>
        private void OnNavigationFailed(object sender, NavigationFailedEventArgs e)
        {
            throw new Exception("Failed to load Page " + e.SourcePageType.FullName);
        }

        /// <summary>
        /// Invoked when application execution is being suspended.  Application state is saved
        /// without knowing whether the application will be terminated or resumed with the contents
        /// of memory still intact.
        /// </summary>
        /// <param name="sender">The source of the suspend request.</param>
        /// <param name="e">Details about the suspend request.</param>
        private void OnSuspending(object sender, SuspendingEventArgs e)
        {
            var deferral = e.SuspendingOperation.GetDeferral();
            //TODO: Save application state and stop any background activity
            deferral.Complete();
        }
    }
}
