/*===========================================================================
 *
 * File:	TaskTime.H
 * Author:	Dave Humphrey (uesp@m0use.net)
 * Created On:	Friday, May 25, 2001
 *
 * Implements the CTaskTimer class for handling a simple timer which
 * calls functions every so many seconds.
 *
 *=========================================================================*/
#ifndef __TASKTIME_H
#define __TASKTIME_H


/*===========================================================================
 *
 * Begin Required Include Files
 *
 *=========================================================================*/
  #include "dl_err.h"
/*===========================================================================
 *		End of Required Include Files
 *=========================================================================*/


/*===========================================================================
 *
 * Begin Definitions
 *
 *=========================================================================*/

	/* Number of different tasks we can handle */
  #define MAX_TIMER_TASKS 20

	/* The first valid task handle */
  #define INITIAL_TASK_HANDLE 1

	/* The timer interrupt under DOS */
  #define DOS_TIMER_INT 0x1C  

/*===========================================================================
 *		End of Definitions
 *=========================================================================*/


/*===========================================================================
 *
 * Begin Type Definitions
 *
 *=========================================================================*/

	/* DOS timer interrupt function type */
  SYS_MSDOS(typedef void interrupt (*PDOS_TIMER_INT)(...));

	/* The task callback function type */
  typedef int (*PTASK_FUNC) (const ulong LastCalled, long UserData);

	/* Task handle used to identify tasks */
  typedef int HTIMERTASK;

	/* Holds the information for one task */
  typedef struct {
    HTIMERTASK Handle;		/* Used to identify the task */
    boolean    Active;		/* Is the task currently active? */
    ulong      TaskRate;	/* How many ms between task calls? */
    ulong      LastCalled;	/* Number of ms since last call */
    PTASK_FUNC pFunc;		/* The task function to call */
    long       UserData;	/* User data to pass to function */
   } task_t;

/*===========================================================================
 *		End of Type Definitions
 *=========================================================================*/


/*===========================================================================
 *
 * Begin Class CTaskTimer Definition
 *
 * Handles a list of functions that should be called every so many 
 * seconds.  
 *
 *=========================================================================*/
class CTaskTimer {

  /*---------- Begin Private Class Members ----------------------*/
private:
  task_t      m_Tasks[MAX_TIMER_TASKS];	/* Array of task information */
  int        m_NumTasks;

  boolean    m_Active;			/* Are we processing tasks? */
  boolean    m_Initialized;		/* Is the timer initialized? */
  HTIMERTASK m_FreeTaskHandle;		/* Keeps track of available task handle */
	
  SYS_WIN32(uint m_TimerID;)		/* The timer ID in Win32 */


	/* To store the previous timer in DOS */
public:
  SYS_MSDOS(PDOS_TIMER_INT m_PrevTimerFunc;)
  


  /*---------- Begin Protected Class Methods --------------------*/
protected:

	/* Find a task array index with the given handle */
  int GetTaskIndex (const HTIMERTASK hTask) const;

  
  /*---------- Begin Public Class Methods -----------------------*/
public:

	/* Class Constructors/Destructors */
  CTaskTimer();
  virtual ~CTaskTimer() { Destroy(); }
  virtual void Destroy (void);
	
	/* Add a new task to the list */
  virtual boolean AddTask (HTIMERTASK& hTask, const ulong Rate, PTASK_FUNC pFunc, const long UserData);

	/* Main task function */
  virtual boolean DoTasks (const ulong Count);

	/* Get class members */
  virtual int     GetNumTasks      (void) const;
  virtual boolean IsActive         (void) const;
  virtual ulong   GetTaskRate      (const HTIMERTASK hTask) const;
  virtual ulong   GetLastCalled    (const HTIMERTASK hTask) const;
  virtual boolean IsActive         (const HTIMERTASK hTask) const;
  virtual boolean IsValidTask      (const HTIMERTASK hTask) const;
  virtual boolean IsValidTaskIndex (const int        iTask) const;
  virtual boolean IsInitialized    (void) const;

	/* Attempt to intialize the task timer */
  virtual boolean Initialize (void);

	/* Attempt to remove a task from the task array */
  virtual boolean RemoveTask (const HTIMERTASK hTask);

	/* Set class members */
  virtual void SetActive   (const boolean Flag);
  virtual void SetActive   (const HTIMERTASK hTask, const boolean Flag);
  virtual void SetTaskRate (const HTIMERTASK hTask, const ulong Rate);
  virtual void SetTaskFunc (const HTIMERTASK hTask, const PTASK_FUNC pFunc);
  virtual void SetUserData (const HTIMERTASK hTask, const long UserData);

 };
/*===========================================================================
 *		End of Class CTaskTimer Definition
 *=========================================================================*/


/*===========================================================================
 *
 * Begin Inline CTaskTimer Methods
 *
 *=========================================================================*/

	/* Get class members */
inline int     CTaskTimer::GetNumTasks   (void) const { return (m_NumTasks); }
inline boolean CTaskTimer::IsActive      (void) const { return (m_Active); }
inline boolean CTaskTimer::IsInitialized (void) const { return (m_Initialized); }
inline boolean CTaskTimer::IsValidTaskIndex (const int TaskIndex) const { return ((TaskIndex >= 0 && TaskIndex < m_NumTasks) ? TRUE : FALSE); }

	/* Set class members */
inline void CTaskTimer::SetActive (const boolean Flag) { m_Active = Flag; }

/*===========================================================================
 *		End of Inline CTaskTimer Methods
 *=========================================================================*/


/*===========================================================================
 *
 * Begin External Variable Definitions
 *
 *=========================================================================*/

	/* The one and only task handler */
  extern CTaskTimer TaskTimer;

/*===========================================================================
 *		End of External Variable Definitions
 *=========================================================================*/



#endif
/*===========================================================================
 *		End of File Tasktime.H
 *=========================================================================*/