#pragma once

#include <functional>

//! (DEPRECATED) This service is used to signal whether something is currently preventing main window from being closed and app from being shut down.
class NOVTABLE app_close_blocker : public service_base
{
public:
	//! Checks whether this service is currently preventing main window from being closed and app from being shut down.
	virtual bool query() = 0;

	//! Static helper function, checks whether any of registered app_close_blocker services is currently preventing main window from being closed and app from being shut down.
	static bool g_query();

	FB2K_MAKE_SERVICE_INTERFACE_ENTRYPOINT(app_close_blocker);
};

//! An interface encapsulating a task preventing the foobar2000 application from being closed. Instances of this class need to be registered using app_close_blocking_task_manager methods. \n
//! Implementation: it's recommended that you derive from app_close_blocking_task_impl class instead of deriving from app_close_blocking_task directly, it manages registration/unregistration behind-the-scenes.
class NOVTABLE app_close_blocking_task {
public:
	//! Retrieves user-friendly name of the task to be shown to the user, should the user try to close foobar2000 while the task is active. \n
	//! Implementation note: this will NOT be called from register_task() or unregister_task(), only in response to user attempting to close foobar2000. \n
	//! Common helper implementations of app_close_blocking_task register from base class constructor while intended query_task_name() override is not yet in place.
	virtual void query_task_name(pfc::string_base & out) = 0;

protected:
	app_close_blocking_task() {}
	~app_close_blocking_task() {}

	PFC_CLASS_NOT_COPYABLE_EX(app_close_blocking_task);
};

//! Entrypoint class for registering app_close_blocking_task instances. \n
//! You can use app_close_blocking_task_impl to call this automatically with your object.
class NOVTABLE app_close_blocking_task_manager : public service_base {
	FB2K_MAKE_SERVICE_COREAPI(app_close_blocking_task_manager);
public:
	//! Registers a task object. \n
	//! Main thread only.
	virtual void register_task(app_close_blocking_task * task) = 0;
	//! Unregisters a task object. \n
	//! Main thread only.
	virtual void unregister_task(app_close_blocking_task * task) = 0;
};

//! Helper; implements standard functionality required by app_close_blocking_task implementations - registers/unregisters the task on construction/destruction.
class app_close_blocking_task_impl : public app_close_blocking_task {
public:
	app_close_blocking_task_impl(const char * name = "<unnamed task>");
	app_close_blocking_task_impl(pfc::string8&& name);
	~app_close_blocking_task_impl();

	//! Override me, or provide name to constructor
	void query_task_name(pfc::string_base & out) override;

	app_close_blocking_task_impl( const app_close_blocking_task_impl & ) = delete;
	void operator=(const app_close_blocking_task_impl & ) = delete;
private:
	const pfc::string8 m_name;
};

class app_close_blocking_task_impl_dynamic : public app_close_blocking_task {
public:
	app_close_blocking_task_impl_dynamic(const char * name = "<unnamed task>") : m_name(name) {}
	~app_close_blocking_task_impl_dynamic() { toggle_blocking(false); }

	//! Override me, or provide name to constructor
	void query_task_name(pfc::string_base & out) override;
	
	void toggle_blocking(bool state);
private:
	bool m_taskActive = false;
	const pfc::string8 m_name;
};


//! \since 1.4.5
//! Provides means for async tasks - running detached from any UI - to reliably finish before the app terminates. \n
//! During a late phase of app shutdown, past initquit ops, when no worker code should be still running - a core-managed instance of abort_callback is signaled, \n
//! then main thread stalls until all objects created with acquire() have been released. \n
//! As this API was introduced out-of-band with 1.4.5, you should use tryGet() to obtain it with FOOBAR2000_TARGET_VERSION < 80, but can safely use ::get() with FOOBAR2000_TARGET_VERSION >= 80.
class async_task_manager : public service_base {
	FB2K_MAKE_SERVICE_COREAPI( async_task_manager );
public:
	virtual abort_callback & get_aborter() = 0;
	virtual service_ptr acquire() = 0;

	//! acquire() helper; returns nullptr if the API isn't available due to old fb2k
	static service_ptr g_acquire();
};

// fb2k::spltiTask() moved to threadsLite.h