package catalogue

import (
	"encoding/json"
	"strings"
	"testing"
)

// A preference has a default in the definition; the mesh's layer, then the node's, override it; a key
// with a default is not stray; and a value that is the operator's still has none (novox/hq ADR 0262).

func notifier() Manifest {
	return Manifest{Module: "notifier",
		Settings: map[string]SettingDeclaration{
			"font-size": {Kind: KindPreference, Default: float64(10), Why: "readable at a scale of one"},
			"width":     {Kind: KindPreference, Default: float64(250), Why: "fits a title of forty characters"},
		},
		Resources: []map[string]any{{"id": "configuration", "type": "file", "path": "/x/notifierrc",
			"content": "font = Inter ${setting:font-size}\nwidth = ${setting:width}\n"}},
	}
}

func parsed(t *testing.T, m Manifest) error {
	t.Helper()
	raw, err := json.Marshal(m)
	if err != nil {
		t.Fatal(err)
	}
	_, err = decodeForTest(raw)
	return err
}

func TestAnUnsetPreferenceTakesItsDefault(t *testing.T) {
	t.Run("the node over the mesh over the default", theNodeOverTheMeshOverTheDefault)
	m := notifier()
	for _, layers := range [][]Layer{nil, {{From: MeshWideLayer, Values: map[string]any{}}}} {
		file := map[string]any{}
		for k, v := range m.Resources[0] {
			file[k] = v
		}
		if err := settingInto(file, WithDefaults(m, layers), m.Module); err != nil {
			t.Fatal(err)
		}
		if file["content"] != "font = Inter 10\nwidth = 250\n" {
			t.Fatalf("filled as %q", file["content"])
		}
	}
	if err := JudgeSettings(m, nil, false); err != nil {
		t.Fatalf("a module whose every key has a default does not compose with no layer: %v", err)
	}
}

func theNodeOverTheMeshOverTheDefault(t *testing.T) {
	m := notifier()
	layers := []Layer{
		{From: MeshWideLayer, Values: map[string]any{"width": float64(300)}},
		{From: "laptop", Values: map[string]any{"font-size": float64(13), "width": float64(340)}},
	}
	file := map[string]any{"type": "file", "content": m.Resources[0]["content"]}
	if err := settingInto(file, WithDefaults(m, layers), m.Module); err != nil {
		t.Fatal(err)
	}
	if file["content"] != "font = Inter 13\nwidth = 340\n" {
		t.Fatalf("filled as %q", file["content"])
	}
	file = map[string]any{"type": "file", "content": m.Resources[0]["content"]}
	if err := settingInto(file, WithDefaults(m, layers[:1]), m.Module); err != nil {
		t.Fatal(err)
	}
	if file["content"] != "font = Inter 10\nwidth = 300\n" {
		t.Fatalf("the mesh's layer over the default filled as %q", file["content"])
	}
}

// Composed for a machine, the way a push writes it: the default reaches the file, and the node's
// layer overrides it.
func TestAComposedMachineGetsTheDefaultAndTheNodesValue(t *testing.T) {
	r := anAdoptedAnchor()
	r.Modules = append(r.Modules, notifier())
	with := anchorRendering(false)
	composed, err := r.Compose(with)
	if err != nil {
		t.Fatal(err)
	}
	if why, left := composed.LeftOut["notifier"]; left {
		t.Fatalf("the notifier was left out: %s", why)
	}
	if c := byID(composed.Resources)["notifier.configuration"]["content"]; c != "font = Inter 10\nwidth = 250\n" {
		t.Fatalf("composed with no layer as %q", c)
	}
	with.Settings["notifier"] = []Layer{{From: "anchor", Values: map[string]any{"font-size": float64(13)}}}
	if composed, err = r.Compose(with); err != nil {
		t.Fatal(err)
	}
	if c := byID(composed.Resources)["notifier.configuration"]["content"]; c != "font = Inter 13\nwidth = 250\n" {
		t.Fatalf("composed with the node's font size as %q", c)
	}
}

// Setting a key the module gives a default is not refused as reaching nothing: it overrides the
// default, which is how a running module gains a setting with no gap between.
func TestAKeyWithADefaultIsNotStray(t *testing.T) {
	m := notifier()
	m.Resources[0]["content"] = "font = Inter ${setting:font-size}\nwidth = ${setting:width}\n"
	stray := UnusedSettings(m, []Layer{{From: "laptop", Values: map[string]any{"font-size": float64(13), "colour": "red"}}})
	joined := strings.Join(stray, "; ")
	if strings.Contains(joined, `"font-size"`) || !strings.Contains(joined, `"colour"`) {
		t.Fatalf("stray: %s", joined)
	}
}

// A default fills ${setting:…} only: it never becomes a key of a mergeable file (issue 168).
func TestADefaultIsNotMergedIntoAJSONFile(t *testing.T) {
	m := notifier()
	m.Resources = append(m.Resources, map[string]any{"id": "other", "type": "file", "path": "/x/other.json",
		"merge": MergeJSON, "content": `{"keep": 1}`})
	out, err := ApplySettings(m.Resources[1], WithDefaults(m, nil))
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(out["content"].(string), "font-size") {
		t.Fatalf("a default reached a mergeable file: %s", out["content"])
	}
}

// A value that is the operator's has no default: no layer setting it is refused by name, as before.
func TestAnOperatorsValueWithoutADefaultIsStillRefused(t *testing.T) {
	m := notifier()
	m.Resources[0]["content"] = "font = Inter ${setting:font-size}\nwidth = ${setting:width}\nfrom = ${setting:domain}\n"
	err := JudgeSettings(m, nil, false)
	if err == nil || !strings.Contains(err.Error(), "${setting:domain}") {
		t.Fatalf("judged %v", err)
	}
	if strings.Contains(err.Error(), "font-size") {
		t.Fatalf("a default was named as set today: %v", err)
	}
}

func TestEveryValueSaysWhereItCameFrom(t *testing.T) {
	m := notifier()
	m.Resources[0]["content"] = m.Resources[0]["content"].(string) + "x = ${setting:position}\n"
	got := Effective(m, []Layer{
		{From: MeshWideLayer, Values: map[string]any{"width": float64(300), "position": "top-right"}},
		{From: "laptop", Values: map[string]any{"font-size": float64(13)}},
	})
	want := map[string]string{"font-size": "laptop", "position": MeshWideLayer, "width": MeshWideLayer}
	if len(got) != 3 {
		t.Fatalf("effective: %+v", got)
	}
	for _, s := range got {
		if s.From != want[s.Key] {
			t.Errorf("%s from %q, want %q", s.Key, s.From, want[s.Key])
		}
	}
	if got[0].Key != "font-size" || got[0].Value != float64(13) || got[0].Default != float64(10) {
		t.Fatalf("font-size: %+v", got[0])
	}
	only := Effective(m, nil)
	if only[0].From != DefaultLayer || only[0].Value != float64(10) {
		t.Fatalf("with no layer: %+v", only)
	}
}

// A node may be called `default`. Its layer is a node's like any other: it overrides the module's
// default, it merges into a mergeable file, and it is named among what is set.
func TestANodeCalledDefaultIsANodesLayer(t *testing.T) {
	m := notifier()
	node := []Layer{{From: DefaultLayer, Values: map[string]any{"font-size": float64(13)}}}
	file := map[string]any{"type": "file", "content": m.Resources[0]["content"]}
	if err := settingInto(file, WithDefaults(m, node), m.Module); err != nil {
		t.Fatal(err)
	}
	if file["content"] != "font = Inter 13\nwidth = 250\n" {
		t.Fatalf("the node called default was dropped: %q", file["content"])
	}
	out, err := ApplySettings(map[string]any{"id": "j", "type": "file", "merge": MergeJSON, "content": `{}`}, node)
	if err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(out["content"].(string), `"font-size": 13`) {
		t.Fatalf("the node called default did not merge: %s", out["content"])
	}
	if got := Effective(m, node); got[0].FromDefault || got[0].Value != float64(13) {
		t.Fatalf("the node's value read as the default: %+v", got[0])
	}
}

// A default fills ${setting:…} in what a module contributes and serves, and never replaces a value a
// contribution states itself.
func TestADefaultFillsAContributionAndAServedFactButNotALiteral(t *testing.T) {
	m := notifier()
	m.Settings["site-title"] = SettingDeclaration{Kind: KindPreference, Default: "Notes", Why: "x"}
	contribution := map[string]any{"title": "${setting:site-title}", "width": "fixed", "port": float64(8080)}
	got, err := overridden(contribution, WithDefaults(m, nil), "a contribution")
	if err != nil {
		t.Fatal(err)
	}
	if got["title"] != "Notes" || got["width"] != "fixed" {
		t.Fatalf("contribution: %v", got)
	}
	got, err = overridden(contribution, WithDefaults(m, []Layer{{From: "laptop", Values: map[string]any{"width": "wide"}}}), "a contribution")
	if err != nil || got["width"] != "wide" {
		t.Fatalf("a node's value did not override a contribution's own key: %v %v", got, err)
	}
	served, err := Settle(map[string]any{"name": "${setting:site-title}"}, WithDefaults(m, nil))
	if err != nil || served["name"] != "Notes" {
		t.Fatalf("served: %v %v", served, err)
	}
	if _, err := Settle(map[string]any{"name": "${setting:site-title}"}, nil); err == nil {
		t.Fatal("a served fact without the defaults was filled")
	}
}

// A module left out for a key this controller does not know, inside an entry, is read past that key
// alone: it still provides what it provides, its other entries are whole, and a key of the same name
// that another entry knows is kept (novox/hq ADR 0262).
func aModuleWithAFieldSetAsideStillProvidesWhatItProvides(t *testing.T) {
	var m Manifest
	raw := `{"module": "later", "version": "2",
		"provides": [{"name": "db", "scope": "mesh"}, {"name": "cache", "a-field-from-later": 1}],
		"state": [{"name": "s", "history": 3}],
		"data": {"own": [{"id": "d", "path": "${dir:d}", "class": "valuable", "backup": {"dump": "x", "into": "d", "class": "later"}}]},
		"resources": [{"id": "d", "type": "directory", "mode": "0700"}]}`
	if err := json.Unmarshal([]byte(raw), &m); err != nil {
		t.Fatal(err)
	}
	if len(m.Provides) != 2 || m.Provides[0].Name != "db" || m.Provides[1].Name != "cache" {
		t.Fatalf("provides: %+v", m.Provides)
	}
	if len(m.State) != 1 || m.State[0].History != 3 {
		t.Fatalf("state: %+v", m.State)
	}
	if m.Data == nil || len(m.Data.Own) != 1 || m.Data.Own[0].Class != "valuable" {
		t.Fatalf("data: the item's own class was taken for the backup's unknown one: %+v", m.Data)
	}
	for _, want := range []string{"provides[1].a-field-from-later", "data.own[0].backup.class"} {
		if !strings.Contains(m.UnknownField(), want) {
			t.Errorf("unknown %q does not say it read without %s", m.UnknownField(), want)
		}
	}
	if why := UnknownFieldReason(m); why != "" {
		t.Fatal(why)
	}
}

// A module with a field set aside is composed whole: its files are declared and its data backed up (novox/hq ADR 0578
// §6; before, ADR 0262 left it out and backed up its data alone).
func aModuleWithAFieldSetAsideIsComposedWhole(t *testing.T) {
	var later Manifest
	if err := json.Unmarshal([]byte(`{"module": "later", "version": "2", "a-field-from-later": 1,
		"resources": [{"id": "d", "type": "directory", "mode": "0700"}, {"id": "rc", "type": "file", "path": "/etc/later.conf", "content": "x\n"}],
		"data": {"own": [{"id": "d", "path": "${dir:d}", "class": "valuable"}]}}`), &later); err != nil {
		t.Fatal(err)
	}
	holder := Manifest{Module: "backups", Version: "1",
		Claims: []Claim{{Name: BackupSeat, Scope: ScopeNode}},
		Resources: []map[string]any{{"id": "list", "type": "file", "path": "/etc/backups.list", "mode": "0644",
			"content": "${contribution:" + BackupSeat + ":backup}"}}}
	r := anAdoptedAnchor()
	r.Modules = append(r.Modules, holder, later)
	composed, err := r.Compose(anchorRendering(false))
	if err != nil {
		t.Fatal(err)
	}
	if _, left := composed.LeftOut["later"]; left {
		t.Fatalf("left out: %v", composed.LeftOut)
	}
	got := byID(composed.Resources)
	if _, declared := got["later.rc"]; !declared {
		t.Fatal("the module's file is not declared")
	}
	list, _ := got["backups.list"]["content"].(string)
	if !strings.Contains(list, "# later") || !strings.Contains(list, "path /var/lib/later/d") {
		t.Fatalf("the left-out module's data is no longer backed up:\n%s", list)
	}
}

// A left-out module's backup lines are best effort: a line that cannot be placed — an access nobody
// placed, a placement setting that does not read — is said among what could not be placed, and the
// machine is declared (novox/hq ADR 0262).
func TestALeftOutModulesUnplaceableBackupLineCostsOnlyThatLine(t *testing.T) {
	holder := Manifest{Module: "backups", Version: "1",
		Claims: []Claim{{Name: BackupSeat, Scope: ScopeNode}},
		Resources: []map[string]any{{"id": "list", "type": "file", "path": "/etc/backups.list", "mode": "0644",
			"content": "${contribution:" + BackupSeat + ":backup}"}}}
	media := Manifest{Module: "media", Version: "1",
		Accesses: []Access{{ID: "library", Mode: "read"}},
		Data:     &Data{Own: []DataItem{{ID: "library", Path: "${access:library}", Class: "valuable"}}}}
	placedBadly := Manifest{Module: "notes", Version: "1",
		Resources: []map[string]any{{"id": "d", "type": "directory", "path": "/srv/notes", "mode": "0700"}},
		Data:      &Data{Own: []DataItem{{ID: "d", Path: "${dir:d}", Class: "valuable"}}}}
	r := anAdoptedAnchor()
	r.Modules = append(r.Modules, holder, media, placedBadly)
	with := anchorRendering(false)
	with.Settings["notes"] = []Layer{LayerOf("anchor", map[string]any{PlacesSetting: "not a map"})}
	composed, err := r.Compose(with)
	if err != nil {
		t.Fatalf("an unplaceable line of a left-out module failed the machine: %v", err)
	}
	for _, m := range []string{"media", "notes"} {
		if _, left := composed.LeftOut[m]; !left {
			t.Errorf("%s is not left out: %v", m, composed.LeftOut)
		}
	}
	unplaced := strings.Join(composed.Unplaced, "\n")
	for _, want := range []string{"media's backup for node-backup", "notes's backup for node-backup", "placement setting does not read"} {
		if !strings.Contains(unplaced, want) {
			t.Errorf("not said among what could not be placed: %q in\n%s", want, unplaced)
		}
	}
	list, _ := byID(composed.Resources)["backups.list"]["content"].(string)
	if strings.Contains(list, "/srv/notes") || strings.Contains(list, "${") {
		t.Fatalf("a line was placed from the definition's default or unfilled:\n%s", list)
	}
}