package catalogue

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

// A provider's consumers' credentials reach it in a file its machine's provisioner client fills (novox/hq ADR 0373,
// issue 679): `${consumers:<provision>}`, which only a provider's template may hold, for a provision it provides, in a
// file of mode 0600 owned at runtime; filled by the client alone, so a module not handed to it on a machine is
// refused there rather than written the placeholder's text, or nothing.

const (
	handedProvider = `{"module":"db","version":"1","moved":true,
  "provides":[{"name":"postgres-database","scope":"mesh","identity":{"max":63,"in":"a PostgreSQL role"}}],
  "build":{"artifacts":[{"name":"files","kind":"archive","from":"files"}]},
  "resources":[
    {"id":"state","type":"directory","mode":"0700","place":"."},
    {"id":"consumers","type":"file","path":"${dir:state}/consumers.json","mode":"0600","template":"files/consumers.json"}]}`
	consumersText = "${consumers:postgres-database}"
)

func builtProvider(text string) []Built {
	return []Built{{Name: "files", Kind: ArtifactArchive,
		Reference: ArtifactStoreScheme + "db/files/blobs/sha256:" + strings.Repeat("f", 64),
		Digest:    "sha256:" + strings.Repeat("f", 64), Texts: map[string]string{"consumers.json": text}}}
}

func TestAHandedProvidersConsumersFileIsHandedToTheClient(t *testing.T) {
	r := notifierOn(t, held(t, handedProvider, builtProvider(consumersText)))
	c, got := composeWith(t, r, handingTo("store:5000"))
	if strings.Contains(got, "${consumers:") {
		t.Fatalf("the declaration carries the placeholder: %s", got)
	}
	plan := c.Plans["db"]
	if len(plan.Files) != 1 || plan.Files[0].Template != "consumers.json" || plan.Files[0].OwnerAtRuntime != RuntimeOwned {
		t.Fatalf("the plan fills %+v, want the consumers' file owned at runtime", plan.Files)
	}
}

func TestWhatAConsumersPlaceholderMayNotBeIsRefused(t *testing.T) {
	for why, c := range map[string]struct{ raw, text, want string }{
		"a provision the module does not provide": {handedProvider, "${consumers:cache}", "does not provide"},
		"a module providing nothing": {strings.Replace(handedProvider, `"provides":[{"name":"postgres-database","scope":"mesh","identity":{"max":63,"in":"a PostgreSQL role"}}],`,
			"", 1), consumersText, "does not provide"},
		"a file others may read": {strings.Replace(handedProvider, `"mode":"0600","template"`,
			`"mode":"0640","template"`, 1), consumersText, "0600"},
		"a file the program keeps": {strings.Replace(handedProvider, `"mode":"0600","template"`,
			`"mode":"0600","create-once":true,"template"`, 1), consumersText, "owned"},
	} {
		m, err := ParseManifest([]byte(c.raw))
		if err != nil {
			t.Fatalf("%s: %v", why, err)
		}
		resolved, err := m.Resolve(builtProvider(c.text))
		if err == nil {
			r := notifierOn(t, resolved)
			_, err = r.Compose(handingTo("store:5000"))
		}
		if err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("%s: %v, want a refusal saying %q", why, err, c.want)
		}
	}
}

// Where the provider is not handed, nothing fills the placeholder, and it is never written as its text or as an empty
// list the provider would read as no consumers: the file is left out, said once, and the module composes exactly as
// it would without the file, so a provider below the handing contract keeps working from its grant files (issue 780).
func TestAProvidersConsumersFileIsLeftOutWhereItIsNotHanded(t *testing.T) {
	withFile := notifierOn(t, held(t, handedProvider, builtProvider(consumersText)))
	without := strings.Replace(handedProvider, `,
    {"id":"consumers","type":"file","path":"${dir:state}/consumers.json","mode":"0600","template":"files/consumers.json"}`, "", 1)
	if without == handedProvider {
		t.Fatal("the manifest without the file was not made")
	}
	bare := notifierOn(t, held(t, strings.Replace(strings.Replace(without, `"moved":true,`, "", 1),
		`"build":{"artifacts":[{"name":"files","kind":"archive","from":"files"}]},`, "", 1), nil))
	for name, with := range map[string]Rendering{
		"a node-engine that fills no file":      {},
		"a node-engine that fills, no client":   {Hands: true, ArtifactStore: "store:5000"},
		"a client, a node-engine that does not": {Provisioner: "mesh-provisioner-client", ArtifactStore: "store:5000"},
	} {
		c, got := composeWith(t, withFile, with)
		_, want := composeWith(t, bare, with)
		if got != want {
			t.Errorf("%s: composes\n%s\nwithout its file, it composed\n%s", name, got, want)
		}
		if strings.Contains(got, "consumers") {
			t.Errorf("%s: the declaration names the consumers' file: %s", name, got)
		}
		if len(c.HandedOnly) != 1 || !strings.Contains(c.HandedOnly[0], "left out, handed only") {
			t.Errorf("%s: said %q, want the one line saying it is left out", name, c.HandedOnly)
		}
		if len(c.Unplaced) != 0 || len(c.Filled) != 0 || len(c.Plans) != 0 {
			t.Errorf("%s: unplaced %v, filled %v, plans %v", name, c.Unplaced, c.Filled, c.Plans)
		}
	}
	// Where it is handed, the file is there and nothing is said.
	c, _ := composeWith(t, withFile, handingTo("store:5000"))
	if len(c.HandedOnly) != 0 || len(c.Filled) != 1 {
		t.Fatalf("handed: said %q, filled %v", c.HandedOnly, c.Filled)
	}
}

// What `module check` and the merge gate judge: the provider read from its tree, its text inline. Judged by the same
// rules, a provider naming a provision it does not provide is refused there too, and one that does composes.
func TestAProviderReadFromItsTreeIsJudgedByTheSameRules(t *testing.T) {
	read := func(text string) (Manifest, error) {
		dir := t.TempDir()
		if err := os.MkdirAll(filepath.Join(dir, "files"), 0o755); err != nil {
			t.Fatal(err)
		}
		if err := os.WriteFile(filepath.Join(dir, "files", "consumers.json"), []byte(text), 0o644); err != nil {
			t.Fatal(err)
		}
		m, err := ParseManifest([]byte(handedProvider))
		if err != nil {
			t.Fatal(err)
		}
		return WithTemplatesFrom(m, dir)
	}
	filled, err := read(consumersText)
	if err != nil {
		t.Fatalf("a provider read from its tree is refused: %v", err)
	}
	if _, err := notifierOn(t, filled).Compose(handingTo("store:5000")); err != nil {
		t.Fatalf("a provider read from its tree does not compose where it would be handed: %v", err)
	}
	if _, err := read("${consumers:cache}"); err == nil || !strings.Contains(err.Error(), "does not provide") {
		t.Fatalf("a provider read from its tree naming a provision it does not provide: %v", err)
	}
}