package catalogue

import (
	"fmt"
	"os"
	"reflect"
	"strings"
	"testing"
)

// The catalogue's foundation modules as they are, parsed by the real parser (novox/hq ADR 0100):
// the store and the broker say which of their ports the mesh guards on an adopted node, and the
// filter module loads its table through a unit of its own whose stop deletes only that table.
func catalogueManifest(t *testing.T, module string) Manifest {
	t.Helper()
	raw, err := os.ReadFile("../../../mesh-catalog/modules/" + module + "/module.json")
	if err != nil {
		t.Skipf("the catalogue is not beside this checkout: %v", err)
	}
	m, err := ParseManifest(raw)
	if err != nil {
		t.Fatalf("%s does not parse:\n%v", module, err)
	}
	return m
}

func TestTheStoreAndTheBrokerSayWhatTheMeshGuards(t *testing.T) {
	if got := catalogueManifest(t, "postgres").Guards; !reflect.DeepEqual(got, []int{5432}) {
		t.Errorf("postgres guards %v; the store's port must be refused from outside", got)
	}
	// The bus's monitoring port, not its client port: a node reaches the bus, nobody outside
	// reads its state (novox/hq ADR 0131 — the broker that guarded 15672 has left the catalogue).
	if got := catalogueManifest(t, "nats").Guards; !reflect.DeepEqual(got, []int{8222}) {
		t.Errorf("nats guards %v; the monitoring port must be refused from outside", got)
	}
}

func TestTheFilterModuleNeverFlushesTheRuleset(t *testing.T) {
	m := catalogueManifest(t, "nftables")
	var unit, stock, load map[string]any
	for _, r := range m.Resources {
		switch r["id"] {
		case "unit":
			unit = r
		case "stock-unit-stop":
			stock = r
		case "load":
			load = r
		}
	}
	if load == nil || load["unit"] != "mesh-filter.service" {
		t.Fatalf("the filter is not loaded by its own unit: %v", load)
	}
	content, _ := unit["content"].(string)
	if unit == nil || unit["path"] != "/etc/systemd/system/mesh-filter.service" {
		t.Fatalf("the filter's unit is not written: %v", unit)
	}
	if strings.Contains(content, "flush") {
		t.Fatalf("stopping the filter flushes the whole ruleset — the runtime's and the found "+
			"firewall's with it:\n%s", content)
	}
	if !strings.Contains(content, "ExecStop=nft delete table inet mesh\n") ||
		!strings.Contains(content, "ExecStart=nft -f "+m.Filtering.Into+"\n") {
		t.Fatalf("the unit does not load the computed rule set and delete only its own table:\n%s",
			content)
	}
	// A node converged before the filter had its own unit still has the stock nftables.service
	// enabled, whose stop flushes the whole ruleset: a drop-in makes it delete only the mesh's
	// table, and the load is restarted on it so the host reloads units and the drop-in is read.
	if stock == nil || stock["path"] != "/etc/systemd/system/nftables.service.d/mesh.conf" ||
		!strings.HasSuffix(fmt.Sprint(stock["content"]),
			"[Service]\nExecStop=\nExecStop=nft delete table inet mesh\n") {
		t.Fatalf("the stock unit's stop is not replaced with deleting the mesh's table: %v", stock)
	}
	// A changed rule set is RELOADED — ExecReload replaces the table in one `nft -f`, so the node
	// is never unfiltered — and only the units themselves restart it, which is the one change a
	// reload cannot carry.
	if !reflect.DeepEqual(load["reload-on"], []any{"filtering"}) {
		t.Fatalf("the filter is restarted rather than reloaded when its rules change, leaving the "+
			"node unfiltered in between: %v", load)
	}
	if !reflect.DeepEqual(load["restart-on"], []any{"unit", "stock-unit-stop"}) {
		t.Fatalf("the filter is not restarted when its unit or the stock unit's drop-in changes: %v",
			load["restart-on"])
	}
}

// The package registry's port is the node's, like every other foundation port (novox/hq
// 04-ISSUES/085, ADR 0100). The forge is reached through what it says it serves, and consumers —
// the builder among them — are told that, rather than carrying a number of their own.

func TestTheForgesPortIsGivenLikeAnyOtherProvidersPort(t *testing.T) {
	forge := catalogueManifest(t, "gitea")

	// The catalogue's number is a default and the node's setting moves it.
	given, err := GivenPorts(forge, []Layer{{From: "anchor",
		Values: map[string]any{PortsSetting: map[string]any{"3000": float64(3100)}}}})
	if err != nil {
		t.Fatalf("the forge's port cannot be given on a node: %v", err)
	}
	if given[3000] != 3100 {
		t.Fatalf("the forge was given %v", given)
	}

	// And every consumer of the package registry is told where the machine actually put it,
	// because that is read from what the forge serves rather than written in the consumer.
	if got := ServedOn(forge, "npm-package-registry", given)["port"]; got != 3100 {
		t.Errorf("the package registry is served on %v, not the port this node gave it", got)
	}
	if got := ServedOn(forge, "npm-package-registry", nil)["port"]; got != float64(3000) {
		t.Errorf("without a setting the forge serves %v, not the catalogue's port", got)
	}
	// And so is where a repository on it is cloned from (novox/hq ADR 0111), for the same reason:
	// a build composes the URL from what the forge serves, so a given port is a followed port.
	if got := ServedOn(forge, "git", given)["port"]; got != 3100 {
		t.Errorf("git is served on %v, not the port this node gave the forge", got)
	}
}

// **The builder requires the registry the npm seat delivers, and carries no binding of its own.**
//
// It used to carry a hand-written binding because nothing provided a package registry to resolve
// one from at genesis. The catalogue now requires it like any consumer, and ADR 0110 makes the
// seat's holder the answer when more than one module provides it — so a carried copy would be a
// second answer to the same question, free to drift from the first. Asserted gone, not merely
// unused.
func TestTheBuilderRequiresTheRegistryTheNpmSeatDelivers(t *testing.T) {
	builder := catalogueManifest(t, "builder")
	seat, _ := SeatNamed("npm-package-registry")
	var requires bool
	for _, r := range builder.Requires {
		requires = requires || r == seat.Delivers
	}
	if !requires {
		t.Fatalf("the builder does not require %q: %v", seat.Delivers, builder.Requires)
	}
	if builder.Binds[seat.Delivers] == "" {
		t.Errorf("the builder is not told where the registry is: binds %v", builder.Binds)
	}
	for _, r := range builder.Resources {
		if fmt.Sprint(r["id"]) == "package-binding" {
			t.Fatal("the builder carries its own package binding beside the one the mesh resolves")
		}
	}
}

// The forge holds the seats it answers for (novox/hq ADR 0110, 0111), parsed by the real parser —
// which refuses a delivering seat claimed by a module that does not provide what it delivers.
func TestTheForgeHoldsTheNpmAndGitSeats(t *testing.T) {
	forge := catalogueManifest(t, "gitea")
	holds := map[string]bool{}
	for _, c := range forge.Claims {
		holds[c.Name] = true
	}
	for _, seat := range []string{"npm-package-registry", "git"} {
		if !holds[seat] {
			t.Errorf("gitea does not claim the %s seat: %+v", seat, forge.Claims)
		}
	}
	git := ServedOn(forge, "git", nil)
	if git["scheme"] != "http" || git["port"] != float64(3000) {
		t.Errorf("gitea serves nothing a clone URL can be composed from: %v", git)
	}
	npm := ServedOn(forge, "npm-package-registry", nil)
	if npm["npm-path"] != "/api/packages/novox/npm/" {
		t.Errorf("gitea no longer says where its npm registry is: %v", npm)
	}
}

// **And the forge's own address follows it**, composed from the manifest in the catalogue beside
// this checkout (novox/hq 04-ISSUES/088).
//
// The forge is reached a third way that neither test above covers: by its own sidecar, over the
// machine's loopback, told where to go in its environment. The `2999:3000` mapping that lets the
// forge go on binding 3000 does nothing for a caller dialling the machine — so a literal there is
// wrong on every node whose assignment differs, and wrong for a second reason on a node given the
// port (ADR 0100). Composed through the whole path, because what proves the placeholder resolves
// in an `env` at all is a declaration, not a manifest.
func TestTheForgesOwnAddressFollowsThePortTheNodeGaveIt(t *testing.T) {
	forge, err := catalogueManifest(t, "gitea").Resolve([]Built{{
		Name: "runtime", Kind: ArtifactImage,
		Reference: "registry.example/gitea-runtime@sha256:" + strings.Repeat("a", 64),
	}})
	if err != nil {
		t.Fatalf("the forge's manifest does not resolve against its own build: %v", err)
	}
	r := Resolution{Node: "anchor", Modules: []Manifest{forge}, Needs: []Needed{
		{Name: "postgres-database", For: "gitea", From: "anchor", At: "127.0.0.1",
			Serves: map[string]any{"port": float64(5432)}, Sealed: "sealed-db"},
		{Name: "route", For: "gitea", From: "anchor"},
		{Name: "secret", For: "gitea", From: "anchor", Local: "internal-token", Sealed: "sealed-token"},
		{Name: "secret", For: "gitea", From: "anchor", Local: "admin", Sealed: "sealed-admin"},
	}}

	// The number this node was given for the forge — the one the machine it is about to run on
	// already publishes.
	out, err := r.Declaration(Rendering{
		Needed: map[string]map[string]string{"gitea": {"broker": "sealed-broker"}},
		Given:  map[string]map[int]int{"gitea": {3000: 2999}},
	})
	if err != nil {
		t.Fatalf("the forge does not compose: %v", err)
	}

	// What the machine publishes, and what the forge's sidecar is told to dial: one number.
	server := fileNamed(out, "gitea.server")
	if server == nil {
		t.Fatalf("the forge's own container is not in the declaration: %v", out)
	}
	if published := fmt.Sprint(server["ports"]); !strings.Contains(published, "2999:3000") {
		t.Fatalf("the forge is not published on the port this node gave it: %v", server["ports"])
	}
	runtime := fileNamed(out, "gitea.runtime")
	if runtime == nil {
		t.Fatalf("the forge's sidecar is not in the declaration: %v", out)
	}
	env, _ := runtime["env"].(map[string]any)
	if env["MESH_GITEA_URL"] != "http://127.0.0.1:2999" {
		t.Fatalf("the forge's sidecar dials %v while the machine publishes the forge on 2999 — "+
			"whatever reads it dials a dead port", env["MESH_GITEA_URL"])
	}
}

// gitea's own sshd is unmodified — the module's own internal port is 22, the number in
// `listens`, the same convention every other module in the catalogue uses (its internal port,
// not an invented identity). Composed from the manifest in the catalogue beside this checkout,
// because what the mesh publishes is a fact about what the module actually writes.
func declaredGiteaSsh(t *testing.T, given map[int]int) map[string]any {
	t.Helper()
	forge := catalogueManifest(t, "gitea")
	resolved, err := forge.Resolve([]Built{{
		Name: "runtime", Kind: ArtifactImage,
		Reference: "registry.example/gitea-runtime@sha256:" + strings.Repeat("a", 64),
	}})
	if err != nil {
		t.Fatalf("the forge's manifest does not resolve against its own build: %v", err)
	}
	r := Resolution{Node: "anchor", Modules: []Manifest{resolved}, Needs: []Needed{
		{Name: "postgres-database", For: "gitea", From: "anchor", At: "127.0.0.1",
			Serves: map[string]any{"port": float64(5432)}, Sealed: "sealed-db"},
		{Name: "route", For: "gitea", From: "anchor"},
		{Name: "secret", For: "gitea", From: "anchor", Local: "internal-token", Sealed: "sealed-token"},
		{Name: "secret", For: "gitea", From: "anchor", Local: "admin", Sealed: "sealed-admin"},
	}}
	givenPorts := map[int]int{3000: 3000}
	for k, v := range given {
		givenPorts[k] = v
	}
	out, err := r.Declaration(Rendering{
		Needed: map[string]map[string]string{"gitea": {"broker": "sealed-broker"}},
		Ports:  map[string]map[int]int{"gitea": givenPorts},
		Given:  map[string]map[int]int{"gitea": given},
	})
	if err != nil {
		t.Fatalf("the forge does not compose: %v", err)
	}
	server := fileNamed(out, "gitea.server")
	if server == nil {
		t.Fatalf("the forge's own container is not in the declaration: %v", out)
	}
	return server
}

// **The forge publishes ssh at the mesh's own fixed convention by default** (novox/hq ADR 0100).
//
// `222` is the mesh's own public convention for the forge's ssh, written directly in the
// manifest's `ports` — every node the forge has run on used the same number, so it needs no
// per-node setting to reach it.
func TestTheForgesSshPortIsTheMeshsFixedConventionByDefault(t *testing.T) {
	forge := catalogueManifest(t, "gitea")
	// Nothing was given — no node moved this port — which is the ordinary answer: the mesh only
	// reports what a setting moved, and the manifest's own `222:22` needs no move to be reached.
	given, err := GivenPorts(forge, nil)
	if err != nil {
		t.Fatalf("the forge's ssh port cannot be given on a node: %v", err)
	}
	if len(given) != 0 {
		t.Fatalf("nothing moved the forge's ssh port, yet it was given %v", given)
	}
	server := declaredGiteaSsh(t, given)
	if published := fmt.Sprint(server["ports"]); !strings.Contains(published, "222:22") {
		t.Fatalf("the forge is published on %v, not its own fixed convention", server["ports"])
	}
}

// **A node whose predecessor served git on a different number can still be told to leave it
// there.** The setting names the port the module itself listens on — 22, gitea's own sshd, the
// same number `listens` uses — not the mesh's own default machine-side number, so moving it does
// not require guessing what the manifest happens to default to.
func TestANodeMayGiveTheForgesSshPortADifferentNumber(t *testing.T) {
	forge := catalogueManifest(t, "gitea")
	given, err := GivenPorts(forge, []Layer{{From: "anchor",
		Values: map[string]any{PortsSetting: map[string]any{"22": float64(9022)}}}})
	if err != nil {
		t.Fatalf("the forge's ssh port cannot be moved on a node: %v", err)
	}
	if want := map[int]int{22: 9022}; !reflect.DeepEqual(given, want) {
		t.Fatalf("the forge was given %v, and the setting named %v", given, want)
	}
	server := declaredGiteaSsh(t, given)
	if published := fmt.Sprint(server["ports"]); !strings.Contains(published, "9022:22") ||
		strings.Contains(published, "222:22") {
		t.Fatalf("the forge is published on %v, not the port this node gave it", server["ports"])
	}
}