/*
 * Copyright 2011-2013, Ingo Weinhold, ingo_weinhold@gmx.de.
 * Distributed under the terms of the MIT License.
 */


#include "AutoPackageAttributeDirectoryCookie.h"

#include "DebugSupport.h"
#include "Utils.h"


AutoPackageAttributeDirectoryCookie::AutoPackageAttributeDirectoryCookie()
        :
        fState(AUTO_PACKAGE_ATTRIBUTE_ENUM_FIRST)
{
}


AutoPackageAttributeDirectoryCookie::~AutoPackageAttributeDirectoryCookie()
{
}


status_t
AutoPackageAttributeDirectoryCookie::Read(dev_t volumeID, ino_t nodeID,
        struct dirent* buffer, size_t bufferSize, uint32* _count)
{
        uint32 maxCount = *_count;
        uint32 count = 0;

        dirent* previousEntry = NULL;

        String customAttributeName = CurrentCustomAttributeName();

        while (fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT
                || !customAttributeName.IsEmpty()) {
                // don't read more entries than requested
                if (count >= maxCount)
                        break;

                // align the buffer for subsequent entries
                if (count > 0) {
                        addr_t offset = (addr_t)buffer % 8;
                        if (offset > 0) {
                                offset = 8 - offset;
                                if (bufferSize <= offset)
                                        break;

                                previousEntry->d_reclen += offset;
                                buffer = (dirent*)((addr_t)buffer + offset);
                                bufferSize -= offset;
                        }
                }

                // get the attribute name
                const String& name = fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT
                        ? AutoPackageAttributes::NameForAttribute(
                                (AutoPackageAttribute)fState)
                        : customAttributeName;

                // fill in the entry name -- checks whether the entry fits into the
                // buffer
                if (!set_dirent_name(buffer, bufferSize, name, strlen(name))) {
                        if (count == 0)
                                RETURN_ERROR(B_BUFFER_OVERFLOW);
                        break;
                }

                // fill in the other data
                buffer->d_dev = volumeID;
                buffer->d_ino = nodeID;

                count++;
                previousEntry = buffer;
                bufferSize -= buffer->d_reclen;
                buffer = (dirent*)((addr_t)buffer + buffer->d_reclen);

                if (fState < AUTO_PACKAGE_ATTRIBUTE_ENUM_COUNT)
                        fState++;
                else
                        customAttributeName = NextCustomAttributeName();
        }

        *_count = count;
        return B_OK;
}


status_t
AutoPackageAttributeDirectoryCookie::Rewind()
{
        fState = AUTO_PACKAGE_ATTRIBUTE_ENUM_FIRST;

        return B_OK;
}


String
AutoPackageAttributeDirectoryCookie::CurrentCustomAttributeName()
{
        return String();
}


String
AutoPackageAttributeDirectoryCookie::NextCustomAttributeName()
{
        return String();
}