#include "FileFunctions.h"
#include <Windows.h>

QString Sao::longFilePath(const QString& path)
{
	// get full path
	DWORD size = GetFullPathNameW((LPCWSTR)path.utf16(), 0, NULL, NULL);
	if (size < 2)
		return QString();
	QString longPath(size - 1, 0);
	size = GetFullPathNameW((LPCWSTR)path.utf16(), size, (LPWSTR)longPath.data(), NULL);
	if (size < DWORD(longPath.size()))
		longPath.resize(size); // the actual number of characters might be less than the initial estimate

	// prepend long path syntax
	if (longPath.startsWith(QStringLiteral("\\\\?\\")))
		return longPath; // already long path syntax
	if (longPath.startsWith(QStringLiteral("\\\\")))
		longPath.insert(2, QStringLiteral("?\\UNC\\"));
	else
		longPath.prepend(QStringLiteral("\\\\?\\"));

	return longPath;
}

quint32 Sao::fileAttributes(const QString& path, quint32 mask /*= 0xFFFFFFFF*/)
{
	return (GetFileAttributesW((LPCWSTR)longFilePath(path).utf16()) & mask);
}

bool Sao::setFileAttributes(const QString& path, quint32 attributes, quint32 mask /*= 0xFFFFFFFF*/)
{
	quint32 attr = fileAttributes(path);
	if ((attr & mask) == (attributes & mask))
		return true; // existing attributes are correct
	attr = (attr & ~mask) | (attributes & mask);
	return (SetFileAttributesW((LPCWSTR)longFilePath(path).utf16(), attr) != 0);
}

bool Sao::hasFileAttributeReadOnly(const QString& path)
{
	return (fileAttributes(path, FILE_ATTRIBUTE_READONLY) != 0);
}

bool Sao::hasFileAttributeHidden(const QString& path)
{
	return (fileAttributes(path, FILE_ATTRIBUTE_HIDDEN) != 0);
}

bool Sao::hasFileAttributeSystem(const QString& path)
{
	return (fileAttributes(path, FILE_ATTRIBUTE_SYSTEM) != 0);
}

bool Sao::setFileAttributeReadOnly(const QString& path, bool readOnly)
{
	return setFileAttributes(path, readOnly ? FILE_ATTRIBUTE_READONLY : 0, FILE_ATTRIBUTE_READONLY);
}

bool Sao::setFileAttributeHidden(const QString& path, bool hidden)
{
	return setFileAttributes(path, hidden ? FILE_ATTRIBUTE_HIDDEN : 0, FILE_ATTRIBUTE_HIDDEN);
}

bool Sao::setFileAttributeSystem(const QString& path, bool system)
{
	return setFileAttributes(path, system ? FILE_ATTRIBUTE_SYSTEM : 0, FILE_ATTRIBUTE_SYSTEM);
}

bool Sao::fileExists(const QString& path)
{
	return (fileAttributes(path) != INVALID_FILE_ATTRIBUTES);
}

namespace // local helpers
{

bool getFileAttributes(const QString& path, WIN32_FILE_ATTRIBUTE_DATA* attributes)
{
	return GetFileAttributesExW((LPCWSTR)Sao::longFilePath(path).utf16(), GetFileExInfoStandard, attributes);
}

QDateTime dateTimeFromLocalTime(const SYSTEMTIME& localTime)
{
	QDate date(localTime.wYear, localTime.wMonth, localTime.wDay);
	QTime time(localTime.wHour, localTime.wMinute, localTime.wSecond, localTime.wMilliseconds);
	return QDateTime(date, time);
}

QDateTime dateTimeFromFileTime(const FILETIME& fileTime)
{
	SYSTEMTIME systemTime;
	if (!FileTimeToSystemTime(&fileTime, &systemTime))
		return QDateTime();
	SYSTEMTIME localTime;
	if (!SystemTimeToTzSpecificLocalTime(NULL, &systemTime, &localTime))
		return QDateTime();
	return dateTimeFromLocalTime(localTime);
}

} // end local helpers

quint64 Sao::fileSize(const QString& path)
{
	WIN32_FILE_ATTRIBUTE_DATA attributes;
	if (!getFileAttributes(path, &attributes))
		return quint64(INVALID_FILE_SIZE) << 32 | INVALID_FILE_SIZE;
	return quint64(attributes.nFileSizeHigh) << 32 | attributes.nFileSizeLow;
}

QDateTime Sao::fileTimeCreated(const QString& path)
{
	WIN32_FILE_ATTRIBUTE_DATA attributes;
	if (!getFileAttributes(path, &attributes))
		return QDateTime();
	return dateTimeFromFileTime(attributes.ftCreationTime);
}

QDateTime Sao::fileTimeLastModified(const QString& path)
{
	WIN32_FILE_ATTRIBUTE_DATA attributes;
	if (!getFileAttributes(path, &attributes))
		return QDateTime();
	return dateTimeFromFileTime(attributes.ftLastWriteTime);
}

QDateTime Sao::fileTimeLastAccessed(const QString& path)
{
	WIN32_FILE_ATTRIBUTE_DATA attributes;
	if (!getFileAttributes(path, &attributes))
		return QDateTime();
	return dateTimeFromFileTime(attributes.ftLastAccessTime);
}