app

type Application interface {
	// Cannot be invoked once the application has been initialised.
	ParseConfig()

	// Initialises the application object.
	//
	// This must be called, as it does several things to set up the
	// various facilities (such as logging) used by the application.
	Init()

	// Run the application.
	//
	// This enters the application's event loop, which will block until
	// the application is subsequently terminated.
	Run()

	// Terminate the application.
	//
	// Breaks out of the event loop, returning control back to the calling
	// function.
	Terminate()

	// Return the application's pretty name.
	Name() string

	// Return the application's version.
	Version() *semver.SemVer

	// Return the application's version control commit identifier.
	Commit() string

	// Return the application's context.
	Context() context.Context

	// Set the parent context for the application.
	//
	// Danger.  Setting this while the application is running can cause
	// unintended side effects due to the old context's cancel function
	// being executed.
	//
	// It is advisable to run this prior to initialisation.
	SetContext(context.Context)

	// Return the application's process manager instance.
	ProcessManager() process.Manager

	// Return the application's logger instance.
	Logger() logger.Logger

	// Return the application's configuration.
	Configuration() config.Config

	// Set the callback that will be invoked when the application starts.
	//
	// If not set, then the default startup handler will be invoked.
	//
	// This cannot be set once the application has been initialised.
	SetOnStart(CallbackFn)

	// Set the callback that will be invoked when the application exits.
	//
	// If not set, then the default exit handler will be invoked.
	//
	/// This cannot be set once the application has been initialised.
	SetOnExit(CallbackFn)

	// Set the callback that will be invoked whenever the event loop
	// fires.
	//
	// If not set, then the default main loop callback will be invoked.
	//
	// This cannot be set once the application has been initialised.
	SetMainLoop(MainLoopFn)

	// Is the application running?
	IsRunning() bool

	// Is the application in 'debug' mode.
	IsDebug() bool

	// Add a responder to the application's responder chain.
	AddResponder(responder.Respondable) (responder.Respondable, error)

	// Remove a responder from the application's responder chain.
	RemoveResponder(responder.Respondable) bool

	// Send an event to the application's responder.
	//
	// Event will be consumed by the first responder that handles it.
	SendFirstResponder(events.Event) (events.Event, bool)

	// Send an event to all the application's responders.
	SendAllResponders(events.Event) []events.Event

	// Return the name of the application's responder chain.
	//
	// Implements `Respondable`.
	Type() string

	// Ascertain if any of the application's responders will respond to
	// an event.
	//
	// The first responder found that responds to the event will result
	// in `true` being returned.
	//
	// Implements `Respondable`.
	RespondsTo(events.Event) bool

	// Send an event to the application's responders.
	//
	// The first object that can respond to the event will consume it.
	//
	// Implements `Respondable`.
	Invoke(events.Event) events.Event
}

type CallbackFn func(Application)

type Config struct {
	// The application's pretty name.
	Name string

	// The application's version number.
	Version *semver.SemVer

	// The application's configuration.
	AppConfig any

	// Validators used to validate the application's configuration.
	Validators config.ValidatorsMap

	// Require CLI flags like '-config' to be provided?
	RequireCLI bool
}

type MainLoopFn func(Application)

type OnSignalFn func(os.Signal)

type SignalResponder struct {
	// contains filtered or unexported fields
}