/*
 * Copyright 2020, Shubham Bhagat, shubhambhagat111@yahoo.com
 * All rights reserved. Distributed under the terms of the MIT License.
 */


#include "BPlusTree.h"
#include "Directory.h"
#include "Extent.h"
#include "LeafDirectory.h"
#include "Node.h"
#include "ShortDirectory.h"


DirectoryIterator::~DirectoryIterator()
{
}


DirectoryIterator*
DirectoryIterator::Init(Inode* inode)
{
        if (inode->Format() == XFS_DINODE_FMT_LOCAL) {
                TRACE("Iterator:Init: LOCAL");
                ShortDirectory* shortDir = new(std::nothrow) ShortDirectory(inode);
                return shortDir;
        }

        if (inode->Format() == XFS_DINODE_FMT_EXTENTS) {
                TRACE("Iterator:Init: EXTENTS");
                status_t status;

                // Check if it is extent based directory
                Extent* extentDir = new(std::nothrow) Extent(inode);
                if (extentDir == NULL)
                        return NULL;

                if (extentDir->IsBlockType()) {
                        status = extentDir->Init();
                        if (status == B_OK)
                                return extentDir;
                }

                delete extentDir;

                // Check if it is leaf based directory
                LeafDirectory* leafDir = new(std::nothrow) LeafDirectory(inode);
                if (leafDir == NULL)
                        return NULL;

                if (leafDir->IsLeafType()) {
                        status = leafDir->Init();
                        if (status == B_OK)
                                return leafDir;
                }

                delete leafDir;

                // Check if it is node based directory
                NodeDirectory* nodeDir = new(std::nothrow) NodeDirectory(inode);
                if (nodeDir == NULL)
                        return NULL;

                if (nodeDir->IsNodeType()) {
                        status = nodeDir->Init();
                        if (status == B_OK)
                                return nodeDir;
                }

                delete nodeDir;
        }

        if (inode->Format() == XFS_DINODE_FMT_BTREE) {
                TRACE("Iterator:Init(): B+TREE");
                TreeDirectory* treeDir = new(std::nothrow) TreeDirectory(inode);
                if (treeDir == NULL)
                        return NULL;

                status_t status = treeDir->InitCheck();

                if (status == B_OK)
                        return treeDir;
        }

        // Invalid format return NULL
        return NULL;