// ActionEngine.h: interface for the CActionEngine class.
//
//////////////////////////////////////////////////////////////////////

#if !defined(AFX_ACTIONENGINE_H__00EC1855_A1A5_11D3_82DB_0020182B97FC__INCLUDED_)
#define AFX_ACTIONENGINE_H__00EC1855_A1A5_11D3_82DB_0020182B97FC__INCLUDED_

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

#include <path.h>
#include "NSMessages.h"

////////////////////////////////////////////////////////////////////////
// Hooks onto any object to provide reference count services

template<class TBase>
class counted_obj
{
public:
	counted_obj() 
		{ m_lCount = 0; }
	long addref() 
		{ return ++m_lCount; }
	long release()
	{
		long lCount = --m_lCount;

		if(lCount <= 0)
			delete (TBase*)this;

		return lCount;
	}
protected:
	long m_lCount;
};

////////////////////////////////////////////////////////////////////////
// Forward Declarations

class CAction;				// Action processed by the Action Engine
class CActionError;			// Error thrown by an Action
class CActionEngine;		// The Engine

/////////////////////////////////////////////////////////////////////////
// Abstract class: An Action for the Action Engine

class CAction
	: public counted_obj<CAction>
{
public:
	CAction() {};
	virtual ~CAction() {};

	// Does the actual action
	virtual bool Do(CActionEngine* pEngine, HWND hwndUpdates) 
		throw(CActionError) = 0;
	// Retry after an error
	virtual bool IsRetryable() const throw() = 0;

	// Try and fix after there's an error
	virtual void Fix(HRESULT hr) throw(CActionError) = 0;
	virtual bool IsFixable(HRESULT hr) const throw() = 0;

protected:
	// Helper function for implementations
	// Updates the dialog
	void Update(HWND hwndUpdates, LPCTSTR szDesc);
	void Update(HWND hwndUpdates, LPCTSTR szStatus, LPCTSTR szDesc);
};



//////////////////////////////////////////////////////////////////////
// An Error thrown by an Action Object and caught by Action Engine
// With built in formatting
//
// %e	Error Text
// %f	File Name
// %F	Full File Path

class CActionError
{
// Constructors
public:
	// These two get the error message from the HRESULT
	CActionError(HRESULT hr, const string& sMessage, 
				 const file_path& path = file_path());
	CActionError(HRESULT hr, UINT nID, 
				 const file_path& path = file_path());

	// These two ask you to supply the error message
	CActionError(const string& sError, HRESULT hr, UINT nID, 
		         const file_path& path = file_path());
	CActionError(const string& sError, HRESULT hr, const string& sMessage, 
		         const file_path& path = file_path());

	string m_sDesc;	// Formatted Error Text
	HRESULT m_hRes;	// Original HRESULT

// Helper Functions
protected:
	void Construct(HRESULT hr, string sMessage, const file_path& path);
	void Construct(const string& sError, HRESULT hr, string sMessage, 
				   const file_path& path);
};

/////////////////////////////////////////////////////////////////////////
// The Engine that processes CAction objects 
// Derives from a vector of Action pointers

typedef std::vector<CAction*> action_array;

class CActionEngine  
	: protected action_array
{
// Construction
public:
	CActionEngine() {};
	CActionEngine(CAction* pFirstAction)
		{ push_back(pFirstAction); }
	virtual ~CActionEngine() 
		{ RemoveAll(); };

// Actions
public:
	// These start engine in current thread
	HRESULT Start(CAction* pFirstAction);
	HRESULT Start();

	// Start engine in another thread and return immediately
	HANDLE StartThread();

// Set Properties
public:
	void SetUpdates(HWND hwndUpdates = NULL, HWND hwndErrors = NULL);

// A few array management functions for the outside world
public:
	UINT Add(CAction* pAction);
	UINT Insert(CAction* pAction, UINT nIndex);
	void Remove(UINT nIndex);
	void RemoveAll(CAction* pKeep = NULL);
	CAction* At(UINT nIndex);

protected:
	HWND m_hwndUpdates;		// Window to Send Updates to
    HWND m_hwndErrors;		// Window to Send Errors to

	// Used to start in a separate thread
	static DWORD CALLBACK ThreadProc(LPVOID lpParam);
};

void Lower(string& s);
#endif // !defined(AFX_ACTIONENGINE_H__00EC1855_A1A5_11D3_82DB_0020182B97FC__INCLUDED_)