#include "fs/ext2/FileSystem.h"

namespace Ext2
{
    FileSystem::FileSystem()
    {
    }

    Result<SharedPtr<VFS::Inode>> FileSystem::find_inode_by_number(ino_t inode)
    {
        auto maybe_inode = m_inode_cache.try_get(inode);
        if (maybe_inode.has_value()) return maybe_inode.value();

        // TODO: Locate the inode's block group descriptor and find it in the block group's inode table.
        return err(ENOENT);
    }

    Result<SharedPtr<VFS::FileSystem>> FileSystem::create(SharedPtr<Device> host_device)
    {
        SharedPtr<FileSystem> fs = TRY(adopt_shared_if_nonnull(new (std::nothrow) FileSystem()));
        const usize nread = TRY(host_device->read((u8*)&fs->m_superblock, 1024, 1024));
        if (nread != 1024) return err(EINVAL);                            // Source had an invalid superblock.
        if (fs->m_superblock.signature != EXT2_MAGIC) return err(EINVAL); // Source had an invalid superblock.

        // TODO: Implement basic Ext2 reading, enough to be able to mount a volume.
        return err(ENOTSUP);
    }
}