package resolution

import (
	"reflect"
	"strings"
	"testing"

	mcat "git.novox.be/novox/mesh-sdk/go/catalogue"
)

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

func windowManager() mcat.Manifest {
	return mcat.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", mcat.DisplayServerSeat))
	got, err := Resolve(cat, []string{"xorg", "i3"}, workstation(), mcat.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", mcat.DisplayServerSeat),
		displayServer("xwayland", "x11-display"))
	// Another machine runs xorg and says so to the world; it does not count.
	world := mcat.World{Offered: map[string][]mcat.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", mcat.DisplayServerSeat)),
		[]string{"i3"}, workstation(), mcat.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(), mcat.World{Unchecked: true}); err != nil {
		t.Errorf("the first pass refused: %v", err)
	}
}

func TestACatalogueDisagreeingAboutAProvisionsReachIsRefused(t *testing.T) {
	cat := shelf(windowManager(), displayServer("xorg", "x11-display"), mcat.Manifest{Module: "fake-x", Provides: mcat.Offers("x11-display")})
	_, err := Resolve(cat, []string{"xorg", "i3"}, workstation(), mcat.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)
	}
}