package catalogue

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

// Defends novox/hq ADR 0208: the graphical session is one module per piece, on the mesh's seats.

// §2: the eleven roles are the mesh's own node seats, each with the verbs it starts with.
func TestTheGraphicalSessionsSeatsAreTheMeshsOwnWithTheirVerbs(t *testing.T) {
	want := map[string][]string{
		LoginManagerSeat:     {"sessions"},
		DisplayServerSeat:    {"displays", "layout"},
		DisplaySessionSeat:   {"reload", "workspaces", "windows"},
		TerminalEmulatorSeat: {"open"},
		LauncherSeat:         {"menu"},
		NotifierSeat:         {"send", "history"},
		LockScreenSeat:       {"lock"},
		ClipboardSeat:        {"history", "copy"},
		BarSeat:              nil,
		CompositorSeat:       nil,
		SecretServiceSeat:    nil,
	}
	for name, verbs := range want {
		s, ok := SeatNamed(name)
		if !ok {
			t.Errorf("%s is not in the mesh's set", name)
			continue
		}
		if s.Scope != ScopeNode || s.Decision != "novox/hq ADR 0208" {
			t.Errorf("%s is %s-scoped under %q", name, s.Scope, s.Decision)
		}
		var got []string
		for _, v := range s.Serves {
			got = append(got, v.Name)
			if v.Description == "" || v.Input["type"] != "object" {
				t.Errorf("%s.%s has no description or no object schema", name, v.Name)
			}
		}
		if !reflect.DeepEqual(got, verbs) {
			t.Errorf("%s serves %v, want %v", name, got, verbs)
		}
	}
	// The launcher's menu takes a list, and the layout verb says its actions.
	menu, _ := SeatNamed(LauncherSeat)
	choices := menu.Serves[0].Input["properties"].(map[string]any)["choices"].(map[string]any)
	if choices["type"] != "array" {
		t.Errorf("menu's choices are %v, not a list", choices["type"])
	}
	display, _ := SeatNamed(DisplayServerSeat)
	action := display.Serves[1].Input["properties"].(map[string]any)["action"].(map[string]any)
	if !reflect.DeepEqual(action["enum"], []string{"list", "save", "apply"}) {
		t.Errorf("layout's actions are %v", action["enum"])
	}
	// And they survive the store's JSON, which is where the live set comes from.
	if _, err := json.Marshal(graphicalSessionSeats()); err != nil {
		t.Fatal(err)
	}
}

// §2: a module may claim one of them, and may not declare it as its own.
func TestNoModuleMayDeclareAGraphicalSessionSeat(t *testing.T) {
	raw := `{"module":"xorg","seats":[{"name":"node-display-server","scope":"node"}]}`
	if _, err := ParseManifest([]byte(raw)); err == nil || !strings.Contains(err.Error(), "mesh's own namespace") {
		t.Fatalf("a module declared node-display-server as its own: %v", err)
	}
}

func displayServer(name, display string, claims ...string) Manifest {
	m := Manifest{Module: name, Provides: []Offer{{Name: display, Reach: ReachMachine}}}
	for _, c := range claims {
		m.Claims = append(m.Claims, Claim{Name: c})
	}
	return m
}

func windowManager() Manifest {
	return Manifest{Module: "i3", Requires: []string{"x11-display"}}
}

// §3: a display is resolved on the requiring module's own node.
func TestAMachineReachRequirementResolvesToTheProviderOnItsOwnNode(t *testing.T) {
	cat := shelf(windowManager(), displayServer("xorg", "x11-display", DisplayServerSeat))
	got, err := Resolve(cat, []string{"xorg", "i3"}, workstation(), World{})
	if err != nil {
		t.Fatalf("i3 beside xorg did not resolve: %v", err)
	}
	if !reflect.DeepEqual(names(got), []string{"xorg", "i3"}) && !reflect.DeepEqual(names(got), []string{"i3", "xorg"}) {
		t.Errorf("resolved %v", names(got))
	}
}

// §3: never answered by installing a provider, and never by another machine's.
func TestAMachineReachRequirementIsNotPulledInNorAnsweredFromAnotherNode(t *testing.T) {
	cat := shelf(windowManager(),
		displayServer("xorg", "x11-display", DisplayServerSeat),
		displayServer("xwayland", "x11-display"))
	// Another machine runs xorg and says so to the world; it does not count.
	world := World{Offered: map[string][]Provider{
		"x11-display": {{Node: "laptop", At: "laptop.mesh", Module: "xorg"}}}}
	_, err := Resolve(cat, []string{"i3"}, workstation(), world)
	if err == nil {
		t.Fatal("i3 resolved on a machine with no display of its own")
	}
	for _, want := range []string{
		`"x11-display" is wanted by i3`, "usable only on the machine that provides it",
		"assign one to workstation", "xorg (holds node-display-server)", "xwayland",
	} {
		if !strings.Contains(err.Error(), want) {
			t.Errorf("the refusal does not say %q:\n%v", want, err)
		}
	}
	// With a single provider in the catalogue too: one candidate is still not a choice to make
	// for somebody, unlike a node-scoped provision without the machine's reach.
	_, err = Resolve(shelf(windowManager(), displayServer("xorg", "x11-display", DisplayServerSeat)),
		[]string{"i3"}, workstation(), World{})
	if err == nil {
		t.Fatal("xorg was pulled in for i3")
	}
	// Not in the first pass, whose refusals take the machine off the network.
	if _, err := Resolve(cat, []string{"i3"}, workstation(), World{Unchecked: true}); err != nil {
		t.Errorf("the first pass refused: %v", err)
	}
}

func TestTheMachinesReachIsAProvisionsOnlyReachAndIsNodeScoped(t *testing.T) {
	for _, c := range []struct{ provides, want string }{
		{`{"name":"x11-display","reach":"internal"}`, `with reach "internal"; a provision's reach is "machine" or nothing`},
		{`{"name":"x11-display","scope":"mesh","reach":"machine"}`, `at scope "mesh" with the machine's reach`},
	} {
		_, err := ParseManifest([]byte(`{"module":"xorg","provides":[` + c.provides + `]}`))
		if err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("%s: want %q, got %v", c.provides, c.want, err)
		}
	}
	m, err := ParseManifest([]byte(`{"module":"xorg","provides":[{"name":"x11-display","reach":"machine"}]}`))
	if err != nil {
		t.Fatal(err)
	}
	if !m.Provides[0].MachineReach() {
		t.Fatal("the reach was not read")
	}
	back, _ := json.Marshal(m.Provides[0])
	if string(back) != `{"name":"x11-display","reach":"machine"}` {
		t.Errorf("written back as %s", back)
	}
}

func TestACatalogueDisagreeingAboutAProvisionsReachIsRefused(t *testing.T) {
	cat := shelf(windowManager(), displayServer("xorg", "x11-display"),
		Manifest{Module: "fake-x", Provides: Offers("x11-display")})
	_, err := Resolve(cat, []string{"xorg", "i3"}, workstation(), World{})
	if err == nil || !strings.Contains(err.Error(), `the catalogue disagrees about "x11-display"`) {
		t.Fatalf("a provision with and without the machine's reach gave %v", err)
	}
}

// §4: xinitrc and xresources slots, placed by the display server's holder alone.
func TestTheSessionsFilesArePlacedByTheDisplayServersHolderAlone(t *testing.T) {
	xorg := Manifest{Module: "xorg", Claims: []Claim{{Name: DisplayServerSeat}},
		Shell: []ShellCode{{For: "xinitrc", Slot: "first", Code: "xset s off"}},
		Resources: []map[string]any{
			{"id": "xinitrc", "type": "file", "path": "/home/op/.xinitrc",
				"content": "${shell:xinitrc:first}${shell:xinitrc:normal}${shell:xinitrc:last}"},
			{"id": "xresources", "type": "file", "path": "/home/op/.Xresources",
				"content": "${shell:xresources:normal}"},
		}}
	i3 := Manifest{Module: "i3", Shell: []ShellCode{{For: "xinitrc", Slot: "last", Code: "exec i3"}}}
	theme := Manifest{Module: "theme", Shell: []ShellCode{
		{For: "xresources", Slot: "normal", Code: "Xft.dpi: 96"},
		{For: "zsh", Slot: "normal", Code: "not for the session"},
	}}
	r := Resolution{Node: "workstation", Account: "op", Modules: []Manifest{xorg, i3, theme}}
	out, err := r.Declaration(Rendering{})
	if err != nil {
		t.Fatal(err)
	}
	by := map[string]any{}
	for _, res := range out {
		by[res["id"].(string)] = res["content"]
	}
	if got := by["xorg.xinitrc"]; got != "# xorg\nxset s off\n# i3\nexec i3\n" {
		t.Errorf("the .xinitrc is %q", got)
	}
	if got := by["xorg.xresources"]; got != "# theme\nXft.dpi: 96\n" {
		t.Errorf("the .Xresources is %q", got)
	}

	// The contributions parse; the placeholders parse only in the holder.
	if _, err := ParseManifest([]byte(`{"module":"i3","shell":[{"for":"xinitrc","slot":"last","code":"exec i3"},` +
		`{"for":"xresources","slot":"normal","code":"i3.font: x"}]}`)); err != nil {
		t.Fatalf("a session contribution was refused: %v", err)
	}
	for _, c := range []struct{ claims, content, want string }{
		{``, "${shell:xinitrc:normal}", "does not claim node-display-server; every module's xinitrc is placed by the display server's holder alone"},
		{`{"name":"node-login-shell"}`, "${shell:xresources:normal}", "does not claim node-display-server"},
		{`{"name":"node-display-server"}`, "${shell:zsh:normal}", "does not claim node-login-shell"},
		{`{"name":"node-display-server"}`, "${shell:xsession:normal}", "the session's file one of xinitrc, xresources"},
	} {
		raw := `{"module":"holder","claims":[` + c.claims + `],"resources":[{"id":"rc","type":"file","path":"/etc/rc","content":"` +
			c.content + `"}]}`
		if _, err := ParseManifest([]byte(raw)); err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("%s with claims [%s]: want %q, got %v", c.content, c.claims, c.want, err)
		}
	}
	if _, err := ParseManifest([]byte(`{"module":"xorg","claims":[{"name":"node-display-server"}],` +
		`"resources":[{"id":"rc","type":"file","path":"/home/op/.xinitrc","content":"${shell:xinitrc:last}"}]}`)); err != nil {
		t.Errorf("the display server's holder could not place the session's slots: %v", err)
	}
}