using System ;
using System.Threading ;
using MediaBrowser.Model.Tasks ;
using Microsoft.Extensions.Logging ;
namespace Emby.Server.Implementations.ScheduledTasks.Triggers
{
/// <summary>
/// Represents a task trigger that fires on a weekly basis.
/// </summary>
public sealed class WeeklyTrigger : ITaskTrigger , IDisposable
{
private readonly TimeSpan _timeOfDay ;
private readonly DayOfWeek _dayOfWeek ;
private Timer ? _timer ;
private bool _disposed = false ;
/// <summary>
/// Initializes a new instance of the <see cref="WeeklyTrigger"/> class.
/// </summary>
/// <param name="timeofDay">The time of day to trigger the task to run.</param>
/// <param name="dayOfWeek">The day of week.</param>
/// <param name="taskOptions">The options of this task.</param>
public WeeklyTrigger ( TimeSpan timeofDay , DayOfWeek dayOfWeek , TaskOptions taskOptions )
{
_timeOfDay = timeofDay ;
_dayOfWeek = dayOfWeek ;
TaskOptions = taskOptions ;
}
/// <summary>
/// Occurs when [triggered].
/// </summary>
public event EventHandler < EventArgs > ? Triggered ;
/// <summary>
/// Gets the options of this task.
/// </summary>
public TaskOptions TaskOptions { get ; }
/// <summary>
/// Stars waiting for the trigger action.
/// </summary>
/// <param name="lastResult">The last result.</param>
/// <param name="logger">The logger.</param>
/// <param name="taskName">The name of the task.</param>
/// <param name="isApplicationStartup">if set to <c>true</c> [is application startup].</param>
public void Start ( TaskResult ? lastResult , ILogger logger , string taskName , bool isApplicationStartup )
{
DisposeTimer ( ) ;
var triggerDate = GetNextTriggerDateTime ( ) ;
_timer = new Timer ( _ = > OnTriggered ( ) , null , triggerDate - DateTime . Now , TimeSpan . FromMilliseconds ( - 1 ) ) ;
}
/// <summary>
/// Gets the next trigger date time.
/// </summary>
/// <returns>DateTime.</returns>
private DateTime GetNextTriggerDateTime ( )
{
var now = DateTime . Now ;
// If it's on the same day
if ( now . DayOfWeek = = _dayOfWeek )
{
// It's either later today, or a week from now
return now . TimeOfDay < _timeOfDay ? now . Date . Add ( _timeOfDay ) : now . Date . AddDays ( 7 ) . Add ( _timeOfDay ) ;
}
var triggerDate = now . Date ;
// Walk the date forward until we get to the trigger day
while ( triggerDate . DayOfWeek ! = _dayOfWeek )
{
triggerDate = triggerDate . AddDays ( 1 ) ;
}
// Return the trigger date plus the time offset
return triggerDate . Add ( _timeOfDay ) ;
}
/// <summary>
/// Stops waiting for the trigger action.
/// </summary>
public void Stop ( )
{
DisposeTimer ( ) ;
}
/// <summary>
/// Disposes the timer.
/// </summary>
private void DisposeTimer ( )
{
_timer ? . Dispose ( ) ;
_timer = null ;
}
/// <summary>
/// Called when [triggered].
/// </summary>
private void OnTriggered ( )
{
Triggered ? . Invoke ( this , EventArgs . Empty ) ;
}
/// <inheritdoc />
public void Dispose ( )
{
if ( _disposed )
{
return ;
}
DisposeTimer ( ) ;
_disposed = true ;
}
}
}