internal/rosa: provide package metadata

This had to be done out-of-band because there was no way to efficiently represent these within Artifact.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/all.go

@@ -120,7 +120,10 @@ const (
 	Zlib
 	Zstd
 
-	buildcatrust
+	// _presetUnexportedStart is the first unexported preset.
+	_presetUnexportedStart
+
+	buildcatrust = iota - 1
 	utilMacros
 
 	// Musl is a standalone libc that does not depend on the toolchain.
@@ -138,131 +141,59 @@ const (
 	_presetEnd
 )
 
-var (
-	// artifactsF is an array of functions for the result of [PArtifact].
-	artifactsF [_presetEnd]func(t Toolchain) pkg.Artifact
+// Metadata is stage-agnostic information of a [PArtifact] not directly
+// representable in the resulting [pkg.Artifact].
+type Metadata struct {
+	f func(t Toolchain) (a pkg.Artifact, version string)
 
-	// artifacts stores the result of artifactsF.
-	artifacts [_toolchainEnd][len(artifactsF)]pkg.Artifact
+	// Unique package name.
+	Name string `json:"name"`
+	// Short user-facing description.
+	Description string `json:"description"`
+	// Project home page.
+	Website string `json:"website,omitempty"`
+}
+
+// Unversioned denotes an unversioned [PArtifact].
+const Unversioned = "\x00"
+
+var (
+	// artifactsM is an array of [PArtifact] metadata.
+	artifactsM [_presetEnd]Metadata
+
+	// artifacts stores the result of Metadata.f.
+	artifacts [_toolchainEnd][len(artifactsM)]pkg.Artifact
+	// versions stores the version of [PArtifact].
+	versions [_toolchainEnd][len(artifactsM)]string
 	// artifactsOnce is for lazy initialisation of artifacts.
-	artifactsOnce [_toolchainEnd][len(artifactsF)]sync.Once
+	artifactsOnce [_toolchainEnd][len(artifactsM)]sync.Once
 )
 
+// GetMetadata returns [Metadata] of a [PArtifact].
+func GetMetadata(p PArtifact) *Metadata { return &artifactsM[p] }
+
 // Load returns the resulting [pkg.Artifact] of [PArtifact].
 func (t Toolchain) Load(p PArtifact) pkg.Artifact {
 	artifactsOnce[t][p].Do(func() {
-		artifacts[t][p] = artifactsF[p](t)
+		artifacts[t][p], versions[t][p] = artifactsM[p].f(t)
 	})
 	return artifacts[t][p]
 }
 
+// Version returns the version string of [PArtifact].
+func (t Toolchain) Version(p PArtifact) string {
+	artifactsOnce[t][p].Do(func() {
+		artifacts[t][p], versions[t][p] = artifactsM[p].f(t)
+	})
+	return versions[t][p]
+}
+
 // ResolveName returns a [PArtifact] by name.
 func ResolveName(name string) (p PArtifact, ok bool) {
-	p, ok = map[string]PArtifact{
-		"initramfs-image": ImageInitramfs,
-
-		"kernel":         Kernel,
-		"kernel-headers": KernelHeaders,
-		"kernel-source":  KernelSource,
-
-		"acl":               ACL,
-		"argp-standalone":   ArgpStandalone,
-		"attr":              Attr,
-		"autoconf":          Autoconf,
-		"automake":          Automake,
-		"bc":                BC,
-		"bash":              Bash,
-		"binutils":          Binutils,
-		"bison":             Bison,
-		"bzip2":             Bzip2,
-		"cmake":             CMake,
-		"coreutils":         Coreutils,
-		"curl":              Curl,
-		"dtc":               DTC,
-		"diffutils":         Diffutils,
-		"elfutils":          Elfutils,
-		"fakeroot":          Fakeroot,
-		"findutils":         Findutils,
-		"flex":              Flex,
-		"fuse":              Fuse,
-		"gmp":               GMP,
-		"glib":              GLib,
-		"gawk":              Gawk,
-		"gen_init_cpio":     GenInitCPIO,
-		"gettext":           Gettext,
-		"git":               Git,
-		"go":                Go,
-		"gperf":             Gperf,
-		"grep":              Grep,
-		"gzip":              Gzip,
-		"hakurei":           Hakurei,
-		"hakurei-dist":      HakureiDist,
-		"iniconfig":         IniConfig,
-		"kmod":              Kmod,
-		"libXau":            LibXau,
-		"libcap":            Libcap,
-		"libexpat":          Libexpat,
-		"libiconv":          Libiconv,
-		"libpsl":            Libpsl,
-		"libseccomp":        Libseccomp,
-		"libucontext":       Libucontext,
-		"libxml2":           Libxml2,
-		"libxslt":           Libxslt,
-		"libffi":            Libffi,
-		"libgd":             Libgd,
-		"libtool":           Libtool,
-		"m4":                M4,
-		"mpc":               MPC,
-		"mpfr":              MPFR,
-		"make":              Make,
-		"meson":             Meson,
-		"mksh":              Mksh,
-		"musl-fts":          MuslFts,
-		"musl-obstack":      MuslObstack,
-		"nss":               NSS,
-		"nss-cacert":        NSSCACert,
-		"ncurses":           Ncurses,
-		"ninja":             Ninja,
-		"openssl":           OpenSSL,
-		"pcre2":             PCRE2,
-		"packaging":         Packaging,
-		"patch":             Patch,
-		"perl":              Perl,
-		"Locale::gettext":   PerlLocaleGettext,
-		"MIME::Charset":     PerlMIMECharset,
-		"Module::Build":     PerlModuleBuild,
-		"Pod::Parser":       PerlPodParser,
-		"SGMLS":             PerlSGMLS,
-		"Term::ReadKey":     PerlTermReadKey,
-		"Text::CharWidth":   PerlTextCharWidth,
-		"Text::WrapI18N":    PerlTextWrapI18N,
-		"Unicode::GCString": PerlUnicodeGCString,
-		"YAML::Tiny":        PerlYAMLTiny,
-		"pkg-config":        PkgConfig,
-		"pluggy":            Pluggy,
-		"procps":            Procps,
-		"pytest":            PyTest,
-		"pygments":          Pygments,
-		"python":            Python,
-		"qemu":              QEMU,
-		"rsync":             Rsync,
-		"sed":               Sed,
-		"setuptools":        Setuptools,
-		"squashfs-tools":    SquashfsTools,
-		"tamago":            TamaGo,
-		"tar":               Tar,
-		"texinfo":           Texinfo,
-		"toybox":            Toybox,
-		"unzip":             Unzip,
-		"util-linux":        UtilLinux,
-		"wayland":           Wayland,
-		"wayland-protocols": WaylandProtocols,
-		"xcb":               XCB,
-		"xcb-proto":         XCBProto,
-		"xproto":            Xproto,
-		"xz":                XZ,
-		"zlib":              Zlib,
-		"zstd":              Zstd,
-	}[name]
-	return
+	for i := range _presetUnexportedStart {
+		if name == artifactsM[i].Name {
+			return i, true
+		}
+	}
+	return 0, false
 }