package builder

import (
	"context"
	"strings"
	"testing"
)

// A build's source fingerprint (novox/hq issue 280): what it was made from, so a rebuild of an unchanged
// source is one build however the image digest it made differs.

const anImage = `{"module":"bus","version":"1",
  "build":{"on":[{"arg":"BASE","image":"vendor/server@sha256:` + "1111111111111111111111111111111111111111111111111111111111111111" + `"}],
    "artifacts":[{"name":"server","kind":"image","from":"Dockerfile"}]},
  "resources":[{"id":"svc","type":"container","name":"bus","artifact":"server"}]}`

func fingerprintOf(t *testing.T, manifest, tree string, mirrored string) string {
	t.Helper()
	r, workspace := aRepository(t, manifest, map[string]string{"modules/bus/Dockerfile": "ARG BASE\nFROM ${BASE}"})
	r.contents["modules/bus/module.json"] = manifest
	r.tree = tree
	m := &mirroring{recorded: r, at: mirrored}
	got, err := Build(context.Background(), r.run, m, "https://forge.invalid/catalogue.git", "modules/bus", "", workspace,
		nil, Npmrc{}, GitCredential{}, nil)
	if err != nil {
		t.Fatal(err)
	}
	return got.Source
}

// mirroring is a store that copies a vendor's image into the mesh's registry, at an address a test says.
type mirroring struct {
	*recorded
	at string
}

func (m *mirroring) MirrorImage(_ context.Context, from, repository string) (string, error) {
	_, digest, _ := strings.Cut(from, "@")
	return m.at + "/" + repository + "@" + digest, nil
}

func TestASourceFingerprintNamesWhatABuildWasMadeFrom(t *testing.T) {
	one := fingerprintOf(t, anImage, "aaaa", "registry-a:5000")
	if !strings.HasPrefix(one, sourcePrefix) {
		t.Fatalf("no fingerprint: %q", one)
	}
	// The same tree and base, the base copied to another registry address: one source.
	if again := fingerprintOf(t, anImage, "aaaa", "registry-b:5000"); again != one {
		t.Fatalf("one source has two fingerprints: %s %s", one, again)
	}
	// The module's tree changed: another source.
	if changed := fingerprintOf(t, anImage, "bbbb", "registry-a:5000"); changed == one {
		t.Fatal("a changed tree kept its fingerprint")
	}
	// The base moved: another source.
	moved := strings.Replace(anImage, "1111111111111111111111111111111111111111111111111111111111111111",
		"2222222222222222222222222222222222222222222222222222222222222222", 1)
	if changed := fingerprintOf(t, moved, "aaaa", "registry-a:5000"); changed == one {
		t.Fatal("a moved base kept its fingerprint")
	}
}

func TestABuildTheRegistryDecidesHasNoFingerprint(t *testing.T) {
	s := newSourceInputs("app")
	s.tree = "aaaa"
	if s.fingerprint() == "" {
		t.Fatal("a pinned source has no fingerprint")
	}
	s.notPinned("it resolves packages from the mesh's registry at build time")
	if got := s.fingerprint(); got != "" {
		t.Fatalf("a build the registry decides has a fingerprint: %s", got)
	}
	if (&sourceInputs{module: "app"}).fingerprint() != "" {
		t.Fatal("a build whose tree was not named has a fingerprint")
	}
}