#if !defined(AFX_IPCCHANNEL_H__D5C2E22C_3F03_4B0E_9D9F_80B686EDBD47__INCLUDED_)
#	define AFX_IPCCHANNEL_H__D5C2E22C_3F03_4B0E_9D9F_80B686EDBD47__INCLUDED_

#	if _MSC_VER > 1000
#		pragma once
#	endif // _MSC_VER > 1000

struct IIPCChannelCallback
{
	virtual void OnIPCPeerConnected()												= 0;
	virtual LRESULT OnIPCNotificationReceived(WORD wCode, LPARAM lParam)			= 0;
	virtual LRESULT OnIPCDataReceived(WORD wCode, const void* pData, SIZE_T cbSize) = 0;
	virtual void OnIPCPeerDisconnected()											= 0;
};

class CSharedBlob;

class CIPCChannel
{
public:
	explicit CIPCChannel(IIPCChannelCallback& callback);
	~CIPCChannel();

	void OpenServerChannel(HWND hwndLocal);
	void OpenClientChannel(HWND hwndLocal, HWND hwndRemote);
	void CloseChannel();

	BOOL IsOpen() const;
	BOOL IsServer() const;
	BOOL IsClient() const;

	void PostNotification(WORD wCode, LPARAM lParam = 0);
	LRESULT SendNotification(WORD wCode, LPARAM lParam = 0);
	LRESULT SendData(WORD wCode, const void* pData, SIZE_T cbSize);

	BOOL ProcessMessage(UINT nMessage, WPARAM wParam, LPARAM lParam, LRESULT& lResult);

private:
	enum ChannelType
	{
		UninitializedChannel,
		ClientChannel,
		ServerChannel
	};

	enum IPCCommand
	{
		cmdClientAttached,
		cmdClientAttachedACK,
		cmdPeerDisconnected,

		cmdNotification,
		cmdData
	};

	BOOL IsPeerAccessible();
	void CloseChannel(BOOL bNotifyPeer);

	void ExecuteAsync(IPCCommand cmd, WORD wCode, LPARAM lParam = 0);
	LRESULT Execute(IPCCommand cmd, WORD wCode, LPARAM lParam = 0);

	CSharedBlob* SetBlob(const void* pData, SIZE_T cbData);
	void ReleaseBlob();

	LRESULT OnCmdClientAttached(LPARAM lParam);
	LRESULT OnCmdClientAttachedACK(LPARAM lParam);
	LRESULT OnCmdPeerDisconnected(LPARAM lParam);
	LRESULT OnCmdNotification(WORD wCode, LPARAM lParam);
	LRESULT OnCmdData(WORD wCode, LPARAM lParam);

private:
	static const UINT m_WM_IPC;

	ChannelType m_type;
	HWND m_hwndLocal;
	HWND m_hwndRemote;
	IIPCChannelCallback& m_Callback;
	CSharedBlob* m_pCurrentBlob;
};

#endif // !defined(AFX_IPCCHANNEL_H__D5C2E22C_3F03_4B0E_9D9F_80B686EDBD47__INCLUDED_)