package catalogue

import (
	"strings"
	"testing"
)

// The manifest in a repository and the manifest the mesh holds are two documents.
//
// A digest is not knowable until something is built, so a repository carrying one would be a
// repository whose file is wrong the moment anybody edits anything — and the mesh would be pinning
// a value nobody could have checked.

func buildable() Manifest {
	return Manifest{
		Module: "meshboard", Version: "1",
		Build: &Build{Artifacts: []Artifact{
			{Name: "server", Kind: ArtifactImage, From: "Dockerfile"},
			{Name: "theme", Kind: ArtifactArchive, From: "files"},
		}},
		Resources: []map[string]any{
			{"id": "svc", "type": "container", "name": "meshboard", "artifact": "server"},
			{"id": "look", "type": "archive", "path": "/opt/meshboard", "artifact": "theme"},
			{"id": "dir", "type": "directory", "path": "/opt/meshboard"},
		},
	}
}

func wasBuilt() []Built {
	return []Built{
		{Name: "server", Kind: ArtifactImage,
			Reference: "registry.invalid/meshboard@sha256:" + strings.Repeat("a", 64)},
		{Name: "theme", Kind: ArtifactArchive,
			Reference: "https://store.invalid/theme.tar.gz",
			Digest:    "sha256:" + strings.Repeat("b", 64)},
	}
}

func TestAResourceNamingAnArtifactBecomesOneNamingTheThing(t *testing.T) {
	got, err := buildable().Resolve(wasBuilt())
	if err != nil {
		t.Fatal(err)
	}
	for _, r := range got.Resources {
		if r["artifact"] != nil {
			// A build-time word the host has never heard of. Leaving it would be a field the
			// strict decoder refuses on the machine, at the worst moment.
			t.Fatalf("%v still names an artifact: %v", r["id"], r)
		}
	}
	if got.Resources[0]["image"] != "registry.invalid/meshboard@sha256:"+strings.Repeat("a", 64) {
		t.Fatalf("the image was not filled in: %v", got.Resources[0])
	}
	if got.Resources[1]["source"] != "https://store.invalid/theme.tar.gz" ||
		got.Resources[1]["digest"] != "sha256:"+strings.Repeat("b", 64) {
		t.Fatalf("the archive was not filled in: %v", got.Resources[1])
	}
	// And a resource that names nothing is untouched.
	if got.Resources[2]["path"] != "/opt/meshboard" || len(got.Resources[2]) != 3 {
		t.Fatalf("an ordinary resource was changed: %v", got.Resources[2])
	}
	// The built manifest carries no build section: it is the derived document, and something
	// holding both would invite somebody to build from it again.
	if got.Build != nil {
		t.Fatal("the built manifest still says how to build itself")
	}
}

func TestAnArtifactDeclaredAndNotBuiltIsRefused(t *testing.T) {
	// A build that did not do what the manifest asked. Said here rather than by a machine later
	// reporting an empty image.
	_, err := buildable().Resolve(wasBuilt()[:1])
	if err == nil {
		t.Fatal("a manifest resolved with an artifact missing")
	}
	if !strings.Contains(err.Error(), "theme") {
		t.Fatalf("the refusal does not name what is missing: %v", err)
	}
	// And it must blame the build rather than the resource. A resource asking for something that
	// does not exist is a manifest fault; a build not producing what the manifest declared is a
	// build fault, and telling somebody to fix the wrong one costs an afternoon.
	if !strings.Contains(err.Error(), "the build did not produce") {
		t.Fatalf("the refusal blames the wrong thing: %v", err)
	}
}

func TestAResourceNamingSomethingTheModuleDoesNotBuildIsRefused(t *testing.T) {
	m := buildable()
	m.Resources = append(m.Resources,
		map[string]any{"id": "other", "type": "archive", "path": "/x", "artifact": "nothing"})
	if _, err := m.Resolve(wasBuilt()); err == nil {
		t.Fatal("a resource naming an artifact nobody builds was accepted")
	}
}

func TestAModuleThatBuildsNothingIsOrdinary(t *testing.T) {
	// Most of what a person installs is configuration. Requiring an empty build section would be
	// a field that exists to be left blank.
	m := Manifest{Module: "shell", Version: "1", Resources: []map[string]any{
		{"id": "rc", "type": "file", "path": "/etc/zsh/zshrc", "content": "setopt"},
	}}
	got, err := m.Resolve(nil)
	if err != nil {
		t.Fatal(err)
	}
	if len(got.Resources) != 1 {
		t.Fatalf("got %v", got.Resources)
	}
}

func TestTwoArtifactsWithOneNameAreRefused(t *testing.T) {
	_, err := ParseManifest([]byte(`{"module":"a","version":"1","build":{"artifacts":[
		{"name":"x","kind":"image","from":"Dockerfile"},
		{"name":"x","kind":"archive","from":"files"}]}}`))
	if err == nil {
		t.Fatal("two artifacts with one name were accepted")
	}
	if !strings.Contains(err.Error(), "could mean either") {
		t.Fatalf("unhelpful refusal: %v", err)
	}
}

func TestAnArtifactBuiltFromOutsideItsRepositoryIsRefused(t *testing.T) {
	// A build reads its own repository and nothing else. A path leaving it would make what gets
	// built depend on whatever happens to be on the machine doing the building.
	for _, from := range []string{"/etc/passwd", "../elsewhere"} {
		_, err := ParseManifest([]byte(`{"module":"a","version":"1","build":{"artifacts":[
			{"name":"x","kind":"archive","from":"` + from + `"}]}}`))
		if err == nil {
			t.Fatalf("%q was accepted as a build input", from)
		}
		if !strings.Contains(err.Error(), "outside its own repository") {
			t.Fatalf("refused for the wrong reason: %v", err)
		}
	}
}

func TestAnArtifactOfAnUnknownKindIsRefused(t *testing.T) {
	_, err := ParseManifest([]byte(`{"module":"a","version":"1","build":{"artifacts":[
		{"name":"x","kind":"binary","from":"main.go"}]}}`))
	if err == nil {
		t.Fatal("an artifact of an unknown kind was accepted")
	}
}