database

type Database struct {
	// Incremented every time the format changes so that migrations may be done.
	Version databaseVersion

	// A map of record id to record.
	Records map[UniqueId]*Record
}

type Field struct {
	// The human-readable title of this field.
	Title string

	// Whether this field is for use by the system, meaning primarily that it
	// can't be removed or modified by the user in any way.
	IsSystemField bool

	// The data this field contains, or the empty string if it contains no data.
	Data string

	// A slice of validation functions to use on this field. Each function should
	// take a pointer to a single field, then return whether the field is
	// considered "valid" or not.
	Validators []func(*Field) bool
}

type Record struct {
	Id        UniqueId
	CreatedAt time.Time

	// The dates this item existed during. If it's the first version of the
	// record, `ValidFrom` will be identical to `CreatedAt`. If it's the current
	// version of the record, `ValidTo` will be `nil`.
	ValidFrom time.Time
	ValidTo   time.Time

	// The title of this record.
	Title string

	// An array of GMail-like string tags, in sorted order, de-duplicated.
	Tags []string

	// The fields used by this record.
	Data []*Field
}

type UniqueId [16]byte