//go:build linux

package fsutils

// https://github.com/torvalds/linux/blob/master/include/uapi/linux/fs.h "Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)"
const (
	SecureDelete       fsAttr = 1 << iota // Secure deletion
	UnDelete                              // Undelete
	CompressFile                          // Compress file
	SyncUpdate                            // Synchronous updates
	Immutable                             // Immutable file
	AppendOnly                            // Writes to file may only append
	NoDumpFile                            // Do not dump file
	NoUpdateAtime                         // Do not update atime
	IsDirty                               // Nobody knows what this does, lol.
	CompressedClusters                    // One or more compressed clusters
	NoCompress                            // Don't compress
	EncFile                               // Encrypted file
	BtreeFmt                              // Btree format dir
	AfsDir                                // AFS directory
	ReservedExt3                          // Reserved for ext3
	NoMergeTail                           // File tail should not be merged
	DirSync                               // dirsync behaviour (directories only)
	DirTop                                // Top of directory hierarchies
	ReservedExt4a                         // Reserved for ext4
	Extents                               // Extents
	VerityProtected                       // Verity-protected inode
	LargeEaInode                          // Inode used for large EA
	ReservedExt4b                         // Reserved for ext4
	NoCOWFile                             // Do not cow file
	_                                     // (Unused)
	DAX                                   // Inode is DAX
	_                                     // (Unused)
	_                                     // (Unused)
	ReservedExt4c                         // Reserved for ext4
	UseParentProjId                       // Create with parents projid
	CaseInsensitive                       // Folder is case-insensitive
	ReservedExt2                          // Reserved for ext2 lib
)

// These are the same value. For some reason.
const (
	HashIdxDir fsAttr = BtreeFmt // Hash-indexed directory
)

var (
	// AttrNameValueMap contains a mapping of attribute names (as designated by this package) to their flag values.
	AttrNameValueMap map[string]fsAttr = map[string]fsAttr{
		"SecureDelete":       SecureDelete,
		"UnDelete":           UnDelete,
		"CompressFile":       CompressFile,
		"SyncUpdate":         SyncUpdate,
		"Immutable":          Immutable,
		"AppendOnly":         AppendOnly,
		"NoDumpFile":         NoDumpFile,
		"NoUpdateAtime":      NoUpdateAtime,
		"IsDirty":            IsDirty,
		"CompressedClusters": CompressedClusters,
		"NoCompress":         NoCompress,
		"EncFile":            EncFile,
		"BtreeFmt":           BtreeFmt,
		"HashIdxDir":         HashIdxDir,
		"AfsDir":             AfsDir,
		"ReservedExt3":       ReservedExt3,
		"NoMergeTail":        NoMergeTail,
		"DirSync":            DirSync,
		"DirTop":             DirTop,
		"ReservedExt4a":      ReservedExt4a,
		"Extents":            Extents,
		"VerityProtected":    VerityProtected,
		"LargeEaInode":       LargeEaInode,
		"ReservedExt4b":      ReservedExt4b,
		"NoCOWFile":          NoCOWFile,
		"DAX":                DAX,
		"ReservedExt4c":      ReservedExt4c,
		"UseParentProjId":    UseParentProjId,
		"CaseInsensitive":    CaseInsensitive,
		"ReservedExt2":       ReservedExt2,
	}

	/*
		AttrValueNameMap contains a mapping of attribute flags to their names (as designated by this package).
		Note the oddball here, BtreeFmt and HashIdxDir are actually the same value, so their string value is unpredictable.
	*/
	AttrValueNameMap map[fsAttr]string = invertMap(AttrNameValueMap)

	// KernelNameValueMap allows lookups using the symbol name as used in the Linux kernel source.
	KernelNameValueMap map[string]fsAttr = map[string]fsAttr{
		"FS_SECRM_FL":        SecureDelete,
		"FS_UNRM_FL":         UnDelete,
		"FS_COMPR_FL":        CompressFile,
		"FS_SYNC_FL":         SyncUpdate,
		"FS_IMMUTABLE_FL":    Immutable,
		"FS_APPEND_FL":       AppendOnly,
		"FS_NODUMP_FL":       NoDumpFile,
		"FS_NOATIME_FL":      NoUpdateAtime,
		"FS_DIRTY_FL":        IsDirty,
		"FS_COMPRBLK_FL":     CompressedClusters,
		"FS_NOCOMP_FL":       NoCompress,
		"FS_ENCRYPT_FL":      EncFile,
		"FS_BTREE_FL":        BtreeFmt,
		"FS_INDEX_FL":        HashIdxDir,
		"FS_IMAGIC_FL":       AfsDir,
		"FS_JOURNAL_DATA_FL": ReservedExt3,
		"FS_NOTAIL_FL":       NoMergeTail,
		"FS_DIRSYNC_FL":      DirSync,
		"FS_TOPDIR_FL":       DirTop,
		"FS_HUGE_FILE_FL":    ReservedExt4a,
		"FS_EXTENT_FL":       Extents,
		"FS_VERITY_FL":       VerityProtected,
		"FS_EA_INODE_FL":     LargeEaInode,
		"FS_EOFBLOCKS_FL":    ReservedExt4b,
		"FS_NOCOW_FL":        NoCOWFile,
		"FS_DAX_FL":          DAX,
		"FS_INLINE_DATA_FL":  ReservedExt4c,
		"FS_PROJINHERIT_FL":  UseParentProjId,
		"FS_CASEFOLD_FL":     CaseInsensitive,
		"FS_RESERVED_FL":     ReservedExt2,
	}

	/*
		KernelValueNameMap contains a mapping of attribute flags to their kernel source symbol name.
		Note the oddball here, BtreeFmt and HashIdxDir are actually the same value, so their string value is unpredictable.
	*/
	KernelValueNameMap map[fsAttr]string = invertMap(KernelNameValueMap)
)