selector

type GrammarError struct {

	// Name is the directory name.
	Name string

	// Word is the word that breaks the grammar.
	Word string

	// Violation is the rule the word breaks.
	Violation Violation

	// Part is the part the word belongs to; empty for an unknown word.
	Part string
}

type Host struct {

	// OS is the operating system's word: Linux, Darwin, Windows.
	OS string

	// Distro is the distribution's word, from os-release's ID: Ubuntu. Empty off Linux, and on a Linux host whose
	// os-release names no distribution.
	Distro string

	// Lineage is the words of the distributions Distro is like, most general first: os-release's ID_LIKE reversed.
	// Ubuntu's is Debian.
	Lineage []string

	// Chain is the OS part's words, most general first. On Linux it follows the lineage the distribution states in
	// os-release: Unix, Linux, ID_LIKE reversed, then ID, so Ubuntu's is Unix, Linux, Debian, Ubuntu.
	Chain []string

	// Arch is the architecture, as runtime.GOARCH names it: arm64, amd64.
	Arch string
}

type OSRelease struct {

	// ID is the distribution's identifier, lowercase: ubuntu, debian, rhel. Empty when the file has none.
	ID string

	// IDLike lists the distributions this one is like, closest first: Rocky's is rhel, centos, fedora.
	IDLike []string

	// VersionID is the distribution's version: 26.04.
	VersionID string

	// VariantID names a variant of the distribution: server, workstation.
	VariantID string
}

type Rank struct {

	// Project is the project's position in the order projects are applied.
	Project int

	// Link is the OS word's position in the host's chain, most general first; 0 when the name has no OS word.
	Link int

	// Arch reports whether the name names the architecture.
	Arch bool

	// Extras reports, for each segment in configured order, whether the name names it.
	Extras []bool
}

type Segment struct {

	// Name is the segment's name: ROLE.
	Name string

	// Values are the values it may take: desktop, server. A directory name carries one of them.
	Values []string

	// Value is this machine's value; empty when unset, and then the segment matches no name.
	Value string
}

type Selected struct {

	// Name is the directory name.
	Name string

	// Project is the project it begins with; empty when names carry no project.
	Project string

	// Rank is its place in the order of application.
	Rank Rank
}

type Selector struct {

	// Host is the machine selected for.
	Host Host

	// Projects are the projects a name may begin with, in the order they're applied: writ's names carry one. Empty when
	// names carry no project, as lore's don't.
	Projects []string

	// Base is the name with no selector words, when names carry no project: lore's Common.
	Base string

	// Segments are the extras, in configured order.
	Segments []Segment
}

type Violation int