package main

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

// askingAController answers the controller's verbs as the seat does: `tools` in-process, the rest as the
// command's output and its JSON.
func askingAController(t *testing.T) Ask {
	t.Helper()
	wrap := func(output string, answer any) json.RawMessage {
		raw, _ := json.Marshal(map[string]any{"ok": true, "output": output, "answer": answer})
		return raw
	}
	return func(address string, args any) (json.RawMessage, error) {
		switch address {
		case "seat:mesh-controller.tools":
			return json.RawMessage(`{"seats":[
				{"seat":"mesh-controller","scope":"mesh","tools":[{"name":"node","description":"What one machine reported it can do, what it is assigned, and why.","replaces":["hostnamectl","uptime"]},{"name":"nodes","description":"Every machine."}]},
				{"seat":"node-service-manager","scope":"node","tools":[
					{"name":"status","description":"One unit as the service manager sees it now: its states, whether it starts at boot.","replaces":["systemctl status","systemctl is-active"]},
					{"name":"journal","description":"The last lines of one unit's journal.","replaces":["journalctl"]}]}]}`), nil
		case "seat:mesh-controller.modules":
			return wrap("[...]", []any{map[string]any{"module": "docker", "on": []string{"anchor"},
				"replaces": map[string][]string{"docker_logs": {"docker logs"}}}, map[string]any{"module": "zsh", "on": []string{"anchor"}}}), nil
		case "seat:mesh-controller.nodes":
			return wrap("", []any{map[string]any{"name": "anchor"}, map[string]any{"name": "laptop"}}), nil
		case "seat:mesh-controller.node":
			node, _ := args.(map[string]any)["node"].(string)
			if node == "anchor" {
				return wrap("anchor\n  mode              converged\n  public domain     Anchor.Example\n\n  what it runs\n", nil), nil
			}
			return wrap("laptop\n  mode              converged\n", nil), nil
		}
		return nil, errors.New("no such verb")
	}
}

func resolving(name string) []string {
	return map[string][]string{"anchor": {"10.10.0.1"}, "anchor.internal": {"10.10.0.1"}, "anchor.example": {"192.0.2.10"},
		"laptop": {"127.0.0.1", "10.10.0.4"}}[name]
}

// What the controller says of its tools and machines is read whole: the seats' verbs, the modules' own tools,
// every machine with its domains and addresses — a loopback address never one of them.
func TestTheMeshsToolsAreAskedOfTheController(t *testing.T) {
	m, err := AskMeshTools(askingAController(t), resolving)
	if err != nil {
		t.Fatal(err)
	}
	var addresses []string
	for _, r := range m.Replacements {
		addresses = append(addresses, r.Address)
	}
	if got := strings.Join(addresses, ","); got != "mesh-controller.node,node-service-manager.status,node-service-manager.journal,docker.docker_logs" {
		t.Errorf("replacements: %s", got)
	}
	if len(m.Machines) != 2 || strings.Join(m.Machines[0].Domains, ",") != "anchor.internal,anchor.example" ||
		strings.Join(m.Machines[0].Addresses, ",") != "10.10.0.1,192.0.2.10" || strings.Join(m.Machines[1].Addresses, ",") != "10.10.0.4" {
		t.Errorf("machines: %+v", m.Machines)
	}
	if m.Replacements[3].Does != "logs" || !m.Replacements[2].NodeScoped || m.Replacements[0].NodeScoped {
		t.Errorf("the rows: %+v", m.Replacements)
	}
}

// **The table is generated, not written** (novox/hq ADR 0245): what the records say a verb replaces is a row,
// the machines' seats first, and nothing is rendered where the records say nothing.
func TestTheInsteadOfTableIsGeneratedFromTheRecords(t *testing.T) {
	m, _ := AskMeshTools(askingAController(t), resolving)
	table := InsteadOf(&m)
	for _, want := range []string{
		"| `<node>/node-service-manager.` | `status` — `systemctl status`, `systemctl is-active` · `journal` — `journalctl` |",
		"| `<node>/docker.` | `docker_logs` — `docker logs` |",
		"| `mesh-controller.` | `node` — `hostnamectl`, `uptime` |",
		"Never `ssh` to a mesh machine",
	} {
		if !strings.Contains(table, want) {
			t.Errorf("the table lacks %q:\n%s", want, table)
		}
	}
	if strings.Index(table, "node-service-manager.") > strings.Index(table, "docker.") ||
		strings.Index(table, "docker.") > strings.Index(table, "`mesh-controller.`") {
		t.Errorf("not the machines' seats, then modules, then the mesh's:\n%s", table)
	}
	// What the guard here named most comes first: its row, and in its row its verb.
	m.Refused = map[string]int{"node-service-manager.journal": 3, "mesh-controller.node": 1}
	ranked := InsteadOf(&m)
	if !strings.Contains(ranked, "| `<node>/node-service-manager.` | `journal` — `journalctl` · `status`") ||
		strings.Index(ranked, "`mesh-controller.`") > strings.Index(ranked, "`<node>/docker.`") {
		t.Errorf("not ranked by the guard's record:\n%s", ranked)
	}
	m.Refused = nil
	if InsteadOf(nil) != "" || InsteadOf(&MeshTools{}) != "" {
		t.Error("a table from nothing")
	}
	// Into the instructions after the mesh's own text, before what was registered.
	out := RenderWithMesh(Facts{Node: "w", Console: "x"}, Settings{}, nil, "/h", nil,
		Config{Mesh: []Item{{Kind: KindInstructions, Name: "conventions", Scope: ScopeMesh, Files: map[string]string{"conventions.md": "Be brief."}}}}, &m)
	md := out["CLAUDE.md"]
	if i, j, k := strings.Index(md, "## Conventions"), strings.Index(md, "## Instead of a shell command"), strings.Index(md, "### conventions"); !(i < j && j < k && i >= 0) {
		t.Errorf("the table is not between the mesh's text and the registered sections:\n%s", md)
	}
	if os.Getenv("SHOW_TABLE") != "" {
		t.Log(table)
	}
	// A long list is cut, and says how the rest is found.
	var many MeshTools
	for i := 0; i < InsteadOfRows+3; i++ {
		many.Replacements = append(many.Replacements, Replacement{Address: "s" + string(rune('a'+i)) + ".v", Seat: true, Replaces: []string{"c"}})
	}
	if t2 := InsteadOf(&many); strings.Count(t2, "| `s") != InsteadOfRows || !strings.Contains(t2, "3 more seats and modules") {
		t.Errorf("not cut to %d rows:\n%s", InsteadOfRows, t2)
	}
}

// Asked again with the same answer, nothing is written and nothing renders.
func TestTheMeshsToolsAreKeptOnlyWhenTheyChange(t *testing.T) {
	p := Paths{State: t.TempDir()}
	m, _ := AskMeshTools(askingAController(t), resolving)
	if !KeepMeshTools(p, m) {
		t.Fatal("the first answer was not kept")
	}
	if KeepMeshTools(p, m) {
		t.Fatal("the same answer was kept again")
	}
	m.Machines = m.Machines[:1]
	if !KeepMeshTools(p, m) || len(ReadMeshTools(p).Machines) != 1 {
		t.Fatal("a changed answer was not kept")
	}
	d := GuardDataOf(Paths{State: p.State, Node: "laptop"}, ReadMeshTools(p))
	if d.Node != "laptop" || len(d.Replacements) != 4 || !strings.HasSuffix(d.Log, "guard.log") {
		t.Errorf("the guard's data: %+v", d)
	}
}

// Where claude-code runs is read from the controller's `modules` answer as it comes — JSON, from `module list
// --json` — and from the printed list too.
func TestTheMachinesRunningTheModuleAreReadFromTheControllersAnswer(t *testing.T) {
	asJSON := json.RawMessage(`{"ok":true,"output":"[...]","answer":[{"module":"zsh","on":["a"]},{"module":"claude-code","on":["a","b"]}]}`)
	if got := strings.Join(NodesRunning(asJSON, "claude-code"), ","); got != "a,b" {
		t.Errorf("from JSON: %q", got)
	}
	printed := json.RawMessage(`{"ok":true,"output":"zsh 1 built x  on a\nclaude-code 1 built y  on a, b\n"}`)
	if got := strings.Join(NodesRunning(printed, "claude-code"), ","); got != "a,b" {
		t.Errorf("from the printed list: %q", got)
	}
	if got := NodesRunning(json.RawMessage(`{"ok":true,"answer":[{"module":"zsh","on":["a"]}]}`), "claude-code"); got != nil {
		t.Errorf("a module that runs nowhere: %v", got)
	}
}