using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tizen.Security;
using Tizen.Sensor;
using Tizen.System;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;

namespace TizenWatchfaceApp1
{
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class WatchFaceApplication : Application
    {
        private const string heartRatePrivilege = "http://tizen.org/privilege/healthinfo";

        private HeartRateMonitor heartRateMonitor = null;

        public ClockViewModel ViewModel { get; set; } = null;

        public WatchFaceApplication()
        {
            InitializeComponent();

            setupPrivilegeHandler();
            checkPrivilegeHandler();

            this.ViewModel = new ClockViewModel();

            this.BindingContext = this.ViewModel;
        }

        protected override void OnSleep()
        {
            base.OnSleep();

            if (heartRateMonitor != null)
            {
                heartRateMonitor.Stop();
            }
        }

        protected override void OnResume()
        {
            base.OnResume();

            setupPrivilegeHandler();

            if (heartRateMonitor != null)
            {
                heartRateMonitor.Start();
            }
        }

        private void heartRateMonitor_DataUpdated(object sender, HeartRateMonitorDataUpdatedEventArgs e)
        {
            if (this.ViewModel != null) this.ViewModel.HeartRate = e.HeartRate;
        }

        private void setupPrivilegeHandler()
        {
            PrivacyPrivilegeManager.ResponseContext context = null;
            if (PrivacyPrivilegeManager.GetResponseContext(heartRatePrivilege).TryGetTarget(out context))
            {
                context.ResponseFetched += privilege_ResponseFetched;
            }
        }

        private void privilege_ResponseFetched(object sender, RequestResponseEventArgs e)
        {
            if (e.cause == CallCause.Error)
            {
                return;
            }

            switch (e.result)
            {
                case RequestResult.AllowForever:
                    if (HeartRateMonitor.IsSupported)
                    {
                        heartRateMonitor = new HeartRateMonitor();
                        heartRateMonitor.DataUpdated += heartRateMonitor_DataUpdated;
                        heartRateMonitor.Start();
                    }

                    break;
                case RequestResult.DenyForever:
                case RequestResult.DenyOnce:
                    break;
            }
        }

        private void checkPrivilegeHandler()
        {
            CheckResult rs = PrivacyPrivilegeManager.CheckPermission(heartRatePrivilege);
            switch (rs)
            {
                case CheckResult.Allow:
                    if (HeartRateMonitor.IsSupported)
                    {
                        heartRateMonitor = new HeartRateMonitor();
                        heartRateMonitor.DataUpdated += heartRateMonitor_DataUpdated;
                    }

                    break;
                case CheckResult.Deny:
                    // do nothing
                    break;
                case CheckResult.Ask:
                    PrivacyPrivilegeManager.RequestPermission(heartRatePrivilege);
                    break;
            }
        }

    }
}