backend

type Backend interface {
	// Create new record
	New([]MetadataStream, []File) (*RecordMetadata, error)

	// Update unvetted record (token, mdAppend, mdOverwrite, fAdd, fDelete)
	UpdateUnvettedRecord([]byte, []MetadataStream, []MetadataStream, []File,
		[]string) (*Record, error)

	// Update vetted record (token, mdAppend, mdOverwrite, fAdd, fDelete)
	UpdateVettedRecord([]byte, []MetadataStream, []MetadataStream, []File,
		[]string) (*Record, error)

	// Update vetted metadata (token, mdAppend, mdOverwrite)
	UpdateVettedMetadata([]byte, []MetadataStream,
		[]MetadataStream) error

	// Get unvetted record
	GetUnvetted([]byte) (*Record, error)

	// Get vetted record
	GetVetted([]byte, string) (*Record, error)

	// Set unvetted record status
	SetUnvettedStatus([]byte, MDStatusT, []MetadataStream,
		[]MetadataStream) (*Record, error)

	// Set vetted record status
	SetVettedStatus([]byte, MDStatusT, []MetadataStream,
		[]MetadataStream) (*Record, error)

	// Inventory retrieves various record records.
	Inventory(uint, uint, bool) ([]Record, []Record, error)

	// Obtain plugin settings
	GetPlugins() ([]Plugin, error)

	// Plugin pass-through command
	Plugin(string, string) (string, string, error) // command type, payload, errror

	// Close performs cleanup of the backend.
	Close()
}

type ContentVerificationError struct {
	ErrorCode    v1.ErrorStatusT
	ErrorContext []string
}

type File struct {
	Name    string // Basename of the file
	MIME    string // MIME type
	Digest  string // SHA256 of decoded Payload
	Payload string // base64 encoded file
}

type MDStatusT int

type MetadataStream struct {
	ID      uint64 // Stream identity
	Payload string // String encoded metadata
}

type Plugin struct {
	ID       string          // Identifier
	Version  string          // Version
	Settings []PluginSetting // Settings
}

type PluginSetting struct {
	Key   string // Name of setting
	Value string // Value of setting
}

type Record struct {
	RecordMetadata RecordMetadata   // Internal metadata
	Version        string           // Version of Files
	Metadata       []MetadataStream // User provided metadata
	Files          []File           // User provided files
}

type RecordMetadata struct {
	Version   uint64    `json:"version"`   // Version of the scruture
	Iteration uint64    `json:"iteration"` // Iteration count of record
	Status    MDStatusT `json:"status"`    // Current status of the record
	Merkle    string    `json:"merkle"`    // Merkle root of all files in record
	Timestamp int64     `json:"timestamp"` // Last updated
	Token     string    `json:"token"`     // Record authentication token
}

type StateTransitionError struct {
	From MDStatusT
	To   MDStatusT
}