/*
     File: CASettingsStorage.cpp
 Abstract: CASettingsStorage.h
  Version: 1.1
 
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 MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION
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 OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.
 
 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL
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*/
//==================================================================================================
//	Includes
//==================================================================================================

//	Self Include
#include "CASettingsStorage.h"

//	PublicUtility Includes
#include "CAAutoDisposer.h"
#include "CACFArray.h"
#include "CACFData.h"
#include "CACFDictionary.h"
#include "CACFDistributedNotification.h"
#include "CACFNumber.h"

//	Stamdard Library Includes
#include <string.h>
#include <sys/fcntl.h>

//==================================================================================================
//	CASettingsStorage
//==================================================================================================

CASettingsStorage::CASettingsStorage(const char* inSettingsFilePath, mode_t inSettingsFileAccessMode, CFPropertyListFormat inSettingsCacheFormat, bool inIsSingleProcessOnly, bool inIsReadOnly)
:
	mSettingsFilePath(NULL),
	mSettingsFileAccessMode(inSettingsFileAccessMode),
	mSettingsCache(CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks)),
	mSettingsCacheFormat(inSettingsCacheFormat),
	mSettingsCacheTime(),
	mSettingsCacheForceRefresh(true),
	mIsSingleProcessOnly(inIsSingleProcessOnly),
	mIsReadOnly(inIsReadOnly)
{
	size_t theLength = strlen(inSettingsFilePath);
	mSettingsFilePath = new char[theLength + 2];
	strlcpy(mSettingsFilePath, inSettingsFilePath, theLength + 2);
	
	mSettingsCacheTime.tv_sec = 0;
	mSettingsCacheTime.tv_nsec = 0;
	
	mSettingsCacheForceRefresh = true;
}

CASettingsStorage::~CASettingsStorage()
{
	delete[] mSettingsFilePath;
	
	if(mSettingsCache != NULL)
	{
		CFRelease(mSettingsCache);
	}
}

UInt32	CASettingsStorage::GetNumberKeys() const
{
	//	make sure our cache is up to date
	const_cast<CASettingsStorage*>(this)->RefreshSettings();

	return ToUInt32(CFDictionaryGetCount(mSettingsCache));
}

void	CASettingsStorage::GetKeys(UInt32 inNumberKeys, UInt32& outNumberKeys, CFStringRef* outKeys) const
{
	//	make sure our cache is up to date
	const_cast<CASettingsStorage*>(this)->RefreshSettings();

	CFDictionaryGetKeysAndValues(mSettingsCache, reinterpret_cast<const void**>(outKeys), NULL);
	outNumberKeys = inNumberKeys;
}

void	CASettingsStorage::CopyBoolValue(CFStringRef inKey, bool& outValue, bool inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	bools can be made from either CFBooleans or CFNumbers
		if(CFGetTypeID(theValue) == CFBooleanGetTypeID())
		{
			//	get the return value from the CF object
			outValue = CFBooleanGetValue(static_cast<CFBooleanRef>(theValue));
		}
		else if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the numeric value
			SInt32 theNumericValue = 0;
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt32Type, &theNumericValue);
			
			//	non-zero indicates true
			outValue = theNumericValue != 0;
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopySInt32Value(CFStringRef inKey, SInt32& outValue, SInt32 inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the return value from the CF object
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt32Type, &outValue);
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopyUInt32Value(CFStringRef inKey, UInt32& outValue, UInt32 inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the return value from the CF object
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt32Type, &outValue);
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopySInt64Value(CFStringRef inKey, SInt64& outValue, SInt64 inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the return value from the CF object
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt64Type, &outValue);
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopyUInt64Value(CFStringRef inKey, UInt64& outValue, UInt64 inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the return value from the CF object
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberSInt64Type, &outValue);
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopyFloat32Value(CFStringRef inKey, Float32& outValue, Float32 inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the return value from the CF object
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberFloat32Type, &outValue);
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopyFloat64Value(CFStringRef inKey, Float64& outValue, Float64 inDefaultValue) const
{
	//	initialize the return value
	outValue = inDefaultValue;
	
	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, NULL);
	
	//	for this type, NULL is an invalid value
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	get the return value from the CF object
			CFNumberGetValue(static_cast<CFNumberRef>(theValue), kCFNumberFloat64Type, &outValue);
		}
		
		//	release the value since we aren't returning it
		CFRelease(theValue);
	}
}

void	CASettingsStorage::CopyNumberValue(CFStringRef inKey, CFNumberRef& outValue, CFNumberRef inDefaultValue) const
{
	//	initialize the return value
	outValue = NULL;

	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, inDefaultValue);
	
	//	for this type, NULL is a valid value, but requires less work
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFNumberGetTypeID())
		{
			//	set the return value to the CF object we are returning
			outValue = static_cast<CFNumberRef>(theValue);
		}
		else
		{
			//	release the value since we aren't returning it
			CFRelease(theValue);
			
			//	set the return value to the default value
			outValue = inDefaultValue;
			
			//	and retain it
			CFRetain(outValue);
		}
	}
}
	
void	CASettingsStorage::CopyStringValue(CFStringRef inKey, CFStringRef& outValue, CFStringRef inDefaultValue) const
{
	//	initialize the return value
	outValue = NULL;

	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, inDefaultValue);
	
	//	for this type, NULL is a valid value, but requires less work
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFStringGetTypeID())
		{
			//	set the return value to the CF object we are returning
			outValue = static_cast<CFStringRef>(theValue);
		}
		else
		{
			//	release the value since we aren't returning it
			CFRelease(theValue);
			
			//	set the return value to the default value
			outValue = inDefaultValue;
			
			//	and retain it
			CFRetain(outValue);
		}
	}
}
	
void	CASettingsStorage::CopyArrayValue(CFStringRef inKey, CFArrayRef& outValue, CFArrayRef inDefaultValue) const
{
	//	initialize the return value
	outValue = NULL;

	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, inDefaultValue);
	
	//	for this type, NULL is a valid value, but requires less work
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFArrayGetTypeID())
		{
			//	set the return value to the CF object we are returning
			outValue = static_cast<CFArrayRef>(theValue);
		}
		else
		{
			//	release the value since we aren't returning it
			CFRelease(theValue);
			
			//	set the return value to the default value
			outValue = inDefaultValue;
			
			//	and retain it
			CFRetain(outValue);
		}
	}
}
	
void	CASettingsStorage::CopyDictionaryValue(CFStringRef inKey, CFDictionaryRef& outValue, CFDictionaryRef inDefaultValue) const
{
	//	initialize the return value
	outValue = NULL;

	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, inDefaultValue);
	
	//	for this type, NULL is a valid value, but requires less work
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFDictionaryGetTypeID())
		{
			//	set the return value to the CF object we are returning
			outValue = static_cast<CFDictionaryRef>(theValue);
		}
		else
		{
			//	release the value since we aren't returning it
			CFRelease(theValue);
			
			//	set the return value to the default value
			outValue = inDefaultValue;
			
			//	and retain it
			CFRetain(outValue);
		}
	}
}
	
void	CASettingsStorage::CopyDataValue(CFStringRef inKey, CFDataRef& outValue, CFDataRef inDefaultValue) const
{
	//	initialize the return value
	outValue = NULL;

	//	get the raw value
	CFTypeRef theValue = NULL;
	CopyCFTypeValue(inKey, theValue, inDefaultValue);
	
	//	for this type, NULL is a valid value, but requires less work
	if(theValue != NULL)
	{
		//	make sure we are dealing with the right kind of CF object
		if(CFGetTypeID(theValue) == CFDataGetTypeID())
		{
			//	set the return value to the CF object we are returning
			outValue = static_cast<CFDataRef>(theValue);
		}
		else
		{
			//	release the value since we aren't returning it
			CFRelease(theValue);
			
			//	set the return value to the default value
			outValue = inDefaultValue;
			
			//	and retain it
			CFRetain(outValue);
		}
	}
}

void	CASettingsStorage::CopyCFTypeValue(CFStringRef inKey, CFTypeRef& outValue, CFTypeRef inDefaultValue) const
{
	//	make sure our cache is up to date
	const_cast<CASettingsStorage*>(this)->RefreshSettings();

	//	check to see if we have a value for the given key
	if(!CFDictionaryGetValueIfPresent(mSettingsCache, inKey, &outValue))
	{
		//	the key wasn't in the cache, so return the default value
		outValue = inDefaultValue;
	}
		
	//	make sure we retain the return value
	if(outValue != NULL)
	{
		CFRetain(outValue);
	}
}

void	CASettingsStorage::SetSInt32Value(CFStringRef inKey, SInt32 inValue)
{
	CACFNumber theValue(inValue);
	SetCFTypeValue(inKey, theValue.GetCFNumber());
}

void	CASettingsStorage::SetUInt32Value(CFStringRef inKey, UInt32 inValue)
{
	CACFNumber theValue(inValue);
	SetCFTypeValue(inKey, theValue.GetCFNumber());
}

void	CASettingsStorage::SetSInt64Value(CFStringRef inKey, SInt64 inValue)
{
	CACFNumber theValue(inValue);
	SetCFTypeValue(inKey, theValue.GetCFNumber());
}

void	CASettingsStorage::SetUInt64Value(CFStringRef inKey, UInt64 inValue)
{
	CACFNumber theValue(inValue);
	SetCFTypeValue(inKey, theValue.GetCFNumber());
}

void	CASettingsStorage::SetFloat32Value(CFStringRef inKey, Float32 inValue)
{
	CACFNumber theValue(inValue);
	SetCFTypeValue(inKey, theValue.GetCFNumber());
}

void	CASettingsStorage::SetFloat64Value(CFStringRef inKey, Float64 inValue)
{
	CACFNumber theValue(inValue);
	SetCFTypeValue(inKey, theValue.GetCFNumber());
}

void	CASettingsStorage::SetNumberValue(CFStringRef inKey, CFNumberRef inValue)
{
	SetCFTypeValue(inKey, inValue);
}

void	CASettingsStorage::SetStringValue(CFStringRef inKey, CFStringRef inValue)
{
	SetCFTypeValue(inKey, inValue);
}

void	CASettingsStorage::SetArrayValue(CFStringRef inKey, CFArrayRef inValue)
{
	SetCFTypeValue(inKey, inValue);
}

void	CASettingsStorage::SetDictionaryValue(CFStringRef inKey, CFDictionaryRef inValue)
{
	SetCFTypeValue(inKey, inValue);
}

void	CASettingsStorage::SetDataValue(CFStringRef inKey, CFDataRef inValue)
{
	SetCFTypeValue(inKey, inValue);
}

void	CASettingsStorage::SetCFTypeValue(CFStringRef inKey, CFTypeRef inValue)
{
	//	make sure our cache is up to date
	RefreshSettings();
	
	//	add the new key/value to the dictionary
	CFDictionarySetValue(mSettingsCache, inKey, inValue);
	
	//	write the settings to the file
	SaveSettings();
}

void	CASettingsStorage::RemoveValue(CFStringRef inKey)
{
	//	make sure our cache is up to date
	RefreshSettings();
	
	//	remove the given key
	CFDictionaryRemoveValue(mSettingsCache, inKey);
	
	//	write the settings to the file
	SaveSettings();
}

void	CASettingsStorage::RemoveAllValues()
{
	//	make sure our cache is up to date
	RefreshSettings();
	
	//	remove the given key
	CFDictionaryRemoveAllValues(mSettingsCache);
	
	//	write the settings to the file
	SaveSettings();
}

void	CASettingsStorage::SendNotification(CFStringRef inName, CFDictionaryRef inData, bool inPostToAllSessions) const
{
	CACFDistributedNotification::PostNotification(inName, inData, inPostToAllSessions);
}

void	CASettingsStorage::ForceRefresh()
{
	mSettingsCacheForceRefresh = true;
}

inline bool	operator<(const struct timespec& inX, const struct timespec& inY)
{
	return ((inX.tv_sec < inY.tv_sec) || ((inX.tv_sec == inY.tv_sec) && (inX.tv_nsec < inY.tv_nsec)));
}

void	CASettingsStorage::RefreshSettings()
{
	//	if this storage is only supporting a single process, there is no need to hit the disk unless
	//	required to by it being the first time or if the refresh is specifically forced for some reason
	if(!mIsSingleProcessOnly || (mSettingsCache == NULL) || ((mSettingsCacheTime.tv_sec == 0) && (mSettingsCacheTime.tv_nsec == 0)) || mSettingsCacheForceRefresh)
	{
		//	first, we need to stat the file to check the mod date, this has the side effect of also
		//	telling us if the file exisits
		struct stat theFileInfo;
		int theStatError = stat(mSettingsFilePath, &theFileInfo);
		
		//	we use this boolean to make error recovery easier since we need a case for when there's no file anyway
		bool theSettingsWereCached = false;
		bool theSettingsNeedSaving = true;
		
		if(theStatError == 0)
		{
			//	stat says there is something there, only have to do work if we either don't have a cache or the cache is out of date
			if((mSettingsCache == NULL) || (mSettingsCacheTime < theFileInfo.st_mtimespec) || mSettingsCacheForceRefresh)
			{
				//	open the file
				FILE* theFile = fopen(mSettingsFilePath, "r");
				if(theFile != NULL)
				{
					//	lock the file (this call blocks until the lock is taken)
					int theError = flock(fileno(theFile), LOCK_EX);
					if(theError == 0)
					{
						//	get the length of the file
						fseek(theFile, 0, SEEK_END);
						size_t theFileLength = static_cast<size_t>(ftell(theFile));
						fseek(theFile, 0, SEEK_SET);
						
						if(theFileLength > 0)
						{
							//	allocate a block of memory to hold the data in the file
							CAAutoFree<Byte> theRawFileData(theFileLength);
							
							//	read all the data in
							fread(static_cast<Byte*>(theRawFileData), theFileLength, 1, theFile);
							
							//	release the lock
							flock(fileno(theFile), LOCK_UN);
							
							//	put it into a CFData object
							CACFData theRawFileDataCFData(static_cast<Byte*>(theRawFileData), static_cast<UInt32>(theFileLength));
							
							//	get rid of the existing cache
							if(mSettingsCache != NULL)
							{
								CFRelease(mSettingsCache);
								mSettingsCache = NULL;
							}
							
							//	parse the data as a property list
							mSettingsCache = (CFMutableDictionaryRef)CFPropertyListCreateWithData(NULL, theRawFileDataCFData.GetCFData(), kCFPropertyListMutableContainersAndLeaves, NULL, NULL);
							
							//	check to be sure we parsed a plist out of the file
							if(mSettingsCache != NULL)
							{
								//	save the date of the cache
								mSettingsCacheTime = theFileInfo.st_mtimespec;
								
								//	mark that we're done
								theSettingsWereCached = true;
								theSettingsNeedSaving = false;
							}
						}
					}
					
					//	close the file
					fclose(theFile);
					mSettingsCacheForceRefresh = false;
				}
			}
			else
			{
				//	nothing to do since the file was older than the cached data
				theSettingsNeedSaving = false;
				theSettingsWereCached = true;
			}
		}
		
		//	if there was a failure, we need to clean up 
		if((theStatError != 0) || theSettingsNeedSaving || !theSettingsWereCached)
		{
			//	we get here if either there isn't a file or something wacky happenned while parsing it
			//	so, make sure we have a valid cache dictionary
			if(mSettingsCache == NULL)
			{
				mSettingsCache = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
			}
			
			mSettingsCacheTime.tv_sec = 0;
			mSettingsCacheTime.tv_nsec = 0;
			
			if((theStatError != 0) || theSettingsNeedSaving)
			{
				SaveSettings();
			}
		}
	}
}

void	CASettingsStorage::SaveSettings()
{
	if(!mIsReadOnly && (mSettingsCache != NULL))
	{
		//	make a CFData that contains the new settings
		CACFData theNewRawPrefsCFData(CFPropertyListCreateData(NULL, mSettingsCache, mSettingsCacheFormat, 0, NULL), true);
		
		//	open the file for writing
		FILE* theFile = fopen(mSettingsFilePath, "w+");
		if(theFile != NULL)
		{
			//	lock the file (this call blocks until the lock is taken)
			int theError = flock(fileno(theFile), LOCK_EX);
			if(theError == 0)
			{
				//	set the file access mode if necessary
				if(mSettingsFileAccessMode != 0)
				{
					fchmod(fileno(theFile), mSettingsFileAccessMode);
				}
				
				//	write the data
				fwrite(theNewRawPrefsCFData.GetDataPtr(), theNewRawPrefsCFData.GetSize(), 1, theFile);
				
				//	flush the file to be sure it is all on disk
				fflush(theFile);
				
				//	release the lock
				flock(fileno(theFile), LOCK_UN);
			
				//	close the file
				fclose(theFile);
				
				//	stat the file to get the mod date
				struct stat theFileInfo;
				stat(mSettingsFilePath, &theFileInfo);
				
				//	save the mod date
				mSettingsCacheTime = theFileInfo.st_mtimespec;
			}
			else
			{
				//	close the file
				fclose(theFile);
			}
		}
	}
}