#ifndef _THREAD_H
#define _THREAD_H

#include "windows.h"

/// 線程封裝.
class thread_base
{
private:
	HANDLE ht;	///< 線程句柄.
	volatile bool p;		///< 暫停標志.
	volatile bool x;		///< 退出標志.
	unsigned long id ;		//thread id
	
	/// 線程函數, 供CreateThread()使用.
	/// 該功能調用派生類的entry().
	static DWORD WINAPI _entry(LPVOID param)
	{
		thread_base* p = (thread_base*)param;
		p->entry() ;
		return 0;
	}

	/// 死等.
	void dead_wait()
	{
		// thread is not even started
		// then return immediately
		if( !ht )
			return;

		WaitForSingleObject(ht, INFINITE);
	}

	/// 關閉線程句柄.
	void close_handle()
	{
		if( !ht )
			return;

		CloseHandle(ht);
		ht = NULL;
	}
protected:
	
	/*! \brief 線程入口, 派生類必須實現!!!
	 *	在線程執行過程中, 派生類有責任在最經常執行的代碼段中
	 *	時時檢查thrd_check_pause()以及thrd_check_exit()
	 *	舉例:
	 *	...
	 *	\code
	 *	if( thrd_check_exit() )
	 *		return;	// exit thread
	 *	thrd_check_pause();
	 *	...
	 *	\endcode
	 */
	virtual void entry() =0;

	
	/// 檢查暫停請求
	inline void check_pause()
	{
		while(p)
		{
			Sleep(1);	// prevent from sucking all the system resources
		}
	}
	
	/// 檢查退出請求.
	/// @return true 線程請求退出, false 忽略
	inline bool check_exit() const
	{
		return x;
	}

	/// 等待一會, 防止資源被獨占
	void wait_a_while(){Sleep(1);}
public:
	/// 構造函數.
	thread_base():ht(NULL), x(false), p(false){}

	/// 析構函數.
	virtual ~thread_base(){thrd_close();}

	/// 判斷線程是否結束.
	/// @return true 線程已經結束, false 線程還在運行.
	bool thrd_is_over()
	{
		// the thread is not even created
		if( !ht )
			return true;

		// check the thread handle
		return WaitForSingleObject(ht, 0) == WAIT_OBJECT_0;
	}

	/// @name 線程功能.
	//@{

	/// 啟動線程.
	/// @return true 線程啟動成功, false 線程啟動失敗
	virtual bool thrd_start(int nPriority)
	{
		// thread is still running
		if( !thrd_is_over() )
			return false;

		x = false;
		
		//				(SECU,STACK,ENTRY, PARAM,RUNNOW?, TH_ID)
		ht = CreateThread(NULL, 0, _entry, this,	0, &id) ;
		if (ht == NULL)  {
			char  sss[50] ;
			sprintf(sss, "CreateThread failed=%ld", GetLastError()) ;
			::MessageBox(NULL, sss, "error", MB_OK) ;
			return false;
		}
		SetThreadPriority(ht, nPriority) ;
		return true;
	}

	/// 暫停線程.
	virtual void thrd_pause()
	{
		p = true;
	}

	/// 繼續暫停的線程.
	virtual void thrd_resume()
	{
		p = false;
	}

	/// 關閉線程.(停止線程)
	virtual DWORD thrd_close(DWORD timeout=5000)
	{
		// if thread is paused, then resume it.
		// so that it could have chance to check exit flag
		if( !ht )
			return 888 ;

		if( p )
			thrd_resume();
		x = true;
		//dead_wait();
		DWORD m_tembool = 9999 ;
	    m_tembool = WaitForSingleObject(ht, timeout) ;

		//close_handle();
		CloseHandle(ht);
		ht = NULL;

		return m_tembool ;
	}

	virtual DWORD thrd_terminate_close()
	{
		if( !ht )
			return 888 ;

		x = true;

		//AfxEndThread(0);
		CloseHandle(ht);
		ht = NULL;

		return 0 ;
	}

	bool thrd_is_paused() const {return p;}
	//@}

};

#define ID_SELF(x) TRACE(CString(x)+_T(" thrd id: %08lx\n"), GetCurrentThreadId());

#define THREAD_CHECK_EXIT if( check_exit() ) break;
#define THREAD_CHECK_PAUSE check_pause();
#define THREAD_CHECK THREAD_CHECK_EXIT; THREAD_CHECK_PAUSE;

#define THREAD_BEGIN for(;;) { THREAD_CHECK;
#define THREAD_END	 }

#endif	// _THREAD_H