storage

type Article_MD struct {
	Arrival time.Time
	Expires time.Time
}

type Article_R interface {
	Releaser
	io.WriterTo
}

type Article_W interface {
	Releaser
	io.Reader
	io.WriterTo
}

type CfgBaseInfo struct {
	Spool string `inn:"$spool"`
}

type CfgHisLoader func(cfg *CfgMaster) (HisMethod, error)

type CfgMaster struct {
	OvMethod  string `inn:"$ovmethod"`
	HisMethod string `inn:"$hismethod"`
	RiMethod  string `inn:"$rimethod"`
	Spool     string `inn:"$pathspool"`
}

type CfgOverviewLoader func(cfg *CfgMaster) (OverviewMethod, error)

type CfgRiLoader func(cfg *CfgMaster) (RiMethod, error)

type CfgStorage struct {
	Methods []*CfgStorageMethod `inn:"@method"`
}

type CfgStorageLoader func(cfg *CfgStorageMethod, bi *CfgBaseInfo) (StorageMethod, error)

type CfgStorageMethod struct {
	Method     string `inn:"$method"`
	Class      int    `inn:"$class"`
	Newsgroups string `inn:"$newsgroup"`
	Size       int64  `inn:"$size"`
	MaxSize    int64  `inn:"$max-size" json:"max-size"`
	Options    string `inn:"$options"`
	ExactMatch bool   `inn:"$exactmatch"`
}

type Cursor interface {
	Releaser
	Next() bool
}

type GroupElement struct {
	Group       []byte
	Status      byte
	Description []byte
}

type GroupMethod interface {
	FetchGroups(status, descr bool, ge *GroupElement) (cur Cursor, err error)
}

type HisMethod interface {
	HisWrite(msgid []byte, md *Article_MD, t *TOKEN) (err error)
	HisLookup(msgid []byte, t *TOKEN) (err error)
	HisCancel(msgid []byte) (err error)
}

type OverviewElement struct {
	Num                              int64
	Subject, From, Date, MsgId, Refs []byte
	Lng, Lines                       int64
}

type OverviewMethod interface {
	FetchOne(grp []byte, num int64, tk *TOKEN, ove *OverviewElement) (rel Releaser, err error)
	FetchAll(grp []byte, num, lastnum int64, tk *TOKEN, ove *OverviewElement) (cur Cursor, err error)
	SeekOne(grp []byte, num int64, back bool, tk *TOKEN, ove *OverviewElement) (rel Releaser, err error)
	GroupStat(grp []byte) (num, low, high int64, err error)

	// Writes a new Overview line into the database.
	GroupWriteOv(grp []byte, autonum bool, md *Article_MD, tk *TOKEN, ove *OverviewElement) (err error)

	// Deletes an Overview line from the database.
	CancelOv(grp []byte, num int64) (err error)

	// Initializes a group in the overview-database.
	InitGroup(grp []byte) (err error)
}

type Releaser interface {
	Release()
}

type RiElement struct {
	Group []byte
	Num   int64
}

type RiHistory struct {
	// IF Group != nil THEN expire a group.
	Group []byte
	Num   int64

	// IF MessageID != nil THEN expire an article.
	MessageId []byte
}

type RiMethod interface {
	// Called for a sequence of group/number-pairs associated to the article
	// This method may return <nil>!
	RiBegin(msgid []byte) RiWriter

	// Performs a reverse index lookup: message-id to the first group/number pair.
	RiLookup(msgid []byte, rie *RiElement) (rel Releaser, err error)

	// Performs a reverse index lookup: message-id to all first group/number pairs.
	RiLookupAll(msgid []byte, rie *RiElement) (rel Cursor, err error)

	// Query Expired articles. SHOULD return message-ids after their group/number counterparts.
	RiQueryExpired(ow *time.Time, rih *RiHistory) (cur Cursor, err error)

	// Expires an article using the message-id.
	RiExpire(msgid []byte) (err error)
}

type RiWriter interface {
	// Called for the first group/number-pair associated to the article
	RiWrite(md *Article_MD, rie *RiElement) (err error)

	// Called for the remaining group/number-pair associated to the article
	RiWriteMore(md *Article_MD, rie *RiElement) (err error)

	// Called at after all group/number-pair have been associated.
	RiCommit() (err error)
}

type SMFlags uint

type SMLevel uint

type StorageManager struct {
	Classes [256]StorageMethod
	Methods [256]*CfgStorageMethod

	/*
		Used by the Posting backend.
		Will hold *fastnntp.WildMat objects.
	*/
	Wildmat [256]interface{}
}

type StorageMethod interface {
	io.Closer

	Store(md *Article_MD, a Article_W, t *TOKEN) (err error)
	Retrieve(t *TOKEN, s SMLevel) (a Article_R, rs SMLevel, err error)
	Cancel(t *TOKEN) (err error)
}

type TOKEN [34]byte