package catalogue

import (
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
)

// Defends novox/hq ADR 0203 (the account's environment is one module's, and every module
// contributes to it) and ADR 0204 (shell code in named slots, placed by the login shell's holder).

// contributors is a fixed set of contributions, in no particular order: what the renderings are
// asserted against byte for byte. go-toolchain and zsh both put ~/.local/bin on PATH, which is the
// ordinary case of two modules sharing a directory, and is written once.
func contributors() []Manifest {
	return []Manifest{
		{Module: "zsh", Environment: &Environment{
			Variables: map[string]string{"XDG_CONFIG_HOME": "${machine:account-home}/.config", "EDITOR": "vim"},
			Path: []PathEntry{
				{Entry: "${machine:account-home}/.local/bin", At: PathAtStart},
				{Entry: "${machine:account-home}/bin", At: PathAtStart},
				{Entry: "/opt/scripts", At: PathAtEnd},
			},
		}},
		{Module: "go-toolchain", Environment: &Environment{
			Variables: map[string]string{"GOPATH": "${machine:account-home}/go"},
			Path: []PathEntry{
				{Entry: "${machine:account-home}/go/bin", At: PathAtStart},
				{Entry: "/usr/local/go/bin", At: PathAtStart},
				{Entry: "${machine:account-home}/.local/bin", At: PathAtStart},
			},
		}},
		{Module: "agent", Environment: &Environment{
			Variables: map[string]string{"DISABLE_AUTOUPDATER": "1"},
			Path:      []PathEntry{{Entry: "/opt/agent/bin", At: PathAtEnd}},
		}},
		// A module contributing nothing is in the set and writes nothing.
		{Module: "postgres"},
	}
}

var operatorFacts = map[string]string{"name": "workstation", "account": "op", "account-home": "/home/op"}

// The final PATH this set composes, around whatever the account had: the start entries in module
// order and then declared order, the account's own, then the end entries.
const composedPOSIX = `# agent
export DISABLE_AUTOUPDATER='1'
# go-toolchain
export GOPATH='/home/op/go'
# zsh
export EDITOR='vim'
export XDG_CONFIG_HOME='/home/op/.config'
# zsh
case ":${PATH}:" in *':/home/op/bin:'*) ;; *) PATH='/home/op/bin'"${PATH:+:${PATH}}" ;; esac
# go-toolchain
case ":${PATH}:" in *':/home/op/.local/bin:'*) ;; *) PATH='/home/op/.local/bin'"${PATH:+:${PATH}}" ;; esac
case ":${PATH}:" in *':/usr/local/go/bin:'*) ;; *) PATH='/usr/local/go/bin'"${PATH:+:${PATH}}" ;; esac
case ":${PATH}:" in *':/home/op/go/bin:'*) ;; *) PATH='/home/op/go/bin'"${PATH:+:${PATH}}" ;; esac
# agent
case ":${PATH}:" in *':/opt/agent/bin:'*) ;; *) PATH="${PATH:+${PATH}:}"'/opt/agent/bin' ;; esac
# zsh
case ":${PATH}:" in *':/opt/scripts:'*) ;; *) PATH="${PATH:+${PATH}:}"'/opt/scripts' ;; esac
export PATH
`

const composedSystemd = `# agent
DISABLE_AUTOUPDATER=1
# go-toolchain
GOPATH=/home/op/go
# zsh
EDITOR=vim
XDG_CONFIG_HOME=/home/op/.config
# go-toolchain, zsh
PATH=/home/op/go/bin:/usr/local/go/bin:/home/op/.local/bin:/home/op/bin${PATH:+:$PATH}
# agent, zsh
PATH=${PATH:+$PATH:}/opt/agent/bin:/opt/scripts
`

func TestTheEnvironmentRendersForAPOSIXShellByteForByte(t *testing.T) {
	env, err := environmentOn(contributors(), operatorFacts)
	if err != nil {
		t.Fatal(err)
	}
	if got := env.posix(); got != composedPOSIX {
		t.Fatalf("the POSIX rendering is\n%s\nnot\n%s", got, composedPOSIX)
	}
}

func TestTheEnvironmentRendersForTheServiceManagerByteForByte(t *testing.T) {
	env, err := environmentOn(contributors(), operatorFacts)
	if err != nil {
		t.Fatal(err)
	}
	if got := env.systemd(); got != composedSystemd {
		t.Fatalf("the environment.d rendering is\n%s\nnot\n%s", got, composedSystemd)
	}
}

// Sourcing twice changes nothing (ADR 0203 §3): a login shell that starts another reads the file
// again, and a PATH that grew each time would be the symptom. Run by a real `sh`, because the claim
// is about what a shell does with the file, not about what the file looks like.
func TestThePOSIXEnvironmentSourcedTwiceLeavesPATHAsOnce(t *testing.T) {
	sh, err := exec.LookPath("sh")
	if err != nil {
		t.Skip("no sh on this machine")
	}
	script := "PATH=/usr/bin:/bin\n" + composedPOSIX + "once=$PATH\n" + composedPOSIX +
		`[ "$PATH" = "$once" ] || { echo "changed: $once -> $PATH"; exit 1; }` + "\n" +
		`echo "$PATH"; echo "$GOPATH"`
	out, err := exec.Command(sh, "-c", script).CombinedOutput()
	if err != nil {
		t.Fatalf("sourcing twice: %v\n%s", err, out)
	}
	lines := strings.Split(strings.TrimSpace(string(out)), "\n")
	want := "/home/op/go/bin:/usr/local/go/bin:/home/op/.local/bin:/home/op/bin:/usr/bin:/bin:/opt/agent/bin:/opt/scripts"
	if lines[0] != want {
		t.Fatalf("PATH is %s, not %s", lines[0], want)
	}
	if lines[1] != "/home/op/go" {
		t.Fatalf("GOPATH was not exported: %q", lines[1])
	}
	// And an entry the account already has stays where it is, and once.
	out, err = exec.Command(sh, "-c", "PATH=/opt/scripts:/usr/bin\n"+composedPOSIX+`echo "$PATH"`).CombinedOutput()
	if err != nil {
		t.Fatalf("%v\n%s", err, out)
	}
	if got := strings.TrimSpace(string(out)); got !=
		"/home/op/go/bin:/usr/local/go/bin:/home/op/.local/bin:/home/op/bin:/opt/scripts:/usr/bin:/opt/agent/bin" {
		t.Fatalf("an entry already on PATH was added again or moved: %s", got)
	}
}

// The environment.d rendering, read by the service manager's own generator where this machine has
// one — the same reader an account's user manager runs, so the PATH it composes is the one asserted.
func TestTheServiceManagerReadsTheSystemdRenderingAsMeant(t *testing.T) {
	generator := "/usr/lib/systemd/user-environment-generators/30-systemd-environment-d-generator"
	if _, err := os.Stat(generator); err != nil {
		t.Skip("no environment.d generator on this machine")
	}
	config := t.TempDir()
	if err := os.MkdirAll(filepath.Join(config, "environment.d"), 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(config, "environment.d", "50-mesh.conf"), []byte(composedSystemd), 0o644); err != nil {
		t.Fatal(err)
	}
	cmd := exec.Command(generator)
	cmd.Env = []string{"PATH=/usr/bin:/bin", "HOME=" + config, "XDG_CONFIG_HOME=" + config}
	out, err := cmd.CombinedOutput()
	if err != nil {
		t.Fatalf("%v\n%s", err, out)
	}
	want := "PATH=/home/op/go/bin:/usr/local/go/bin:/home/op/.local/bin:/home/op/bin:/usr/bin:/bin:/opt/agent/bin:/opt/scripts"
	if !strings.Contains(string(out), want+"\n") || !strings.Contains(string(out), "GOPATH=/home/op/go\n") {
		t.Fatalf("the service manager read\n%s", out)
	}
}

// Nothing contributed renders nothing, in both formats — not an empty `export PATH`.
func TestNoContributionsRenderNothing(t *testing.T) {
	env, err := environmentOn([]Manifest{{Module: "postgres"}}, operatorFacts)
	if err != nil {
		t.Fatal(err)
	}
	if env.posix() != "" || env.systemd() != "" {
		t.Fatalf("an empty environment rendered %q and %q", env.posix(), env.systemd())
	}
}

// A ${machine:…} fact the machine does not have is refused naming the module, as a file's is.
func TestAContributedFactTheMachineLacksIsRefused(t *testing.T) {
	_, err := environmentOn(contributors(), map[string]string{"name": "server"})
	if err == nil || !strings.Contains(err.Error(), "go-toolchain sets GOPATH") ||
		!strings.Contains(err.Error(), "${machine:account-home}") {
		t.Fatalf("a missing account home was not refused by name: %v", err)
	}
}

// ADR 0203 §5: two modules setting one variable are refused, both named — neither silently wins.
func TestAVariableTwoModulesSetIsRefusedNamingBoth(t *testing.T) {
	modules := append(contributors(), Manifest{Module: "neovim", Environment: &Environment{
		Variables: map[string]string{"EDITOR": "nvim"}}})
	_, err := environmentOn(modules, operatorFacts)
	if err == nil || err.Error() != "neovim and zsh both set EDITOR on this machine; the account has one "+
		"environment, so one of them must stop setting it (novox/hq ADR 0203)" {
		t.Fatalf("a variable set twice was not refused naming both: %v", err)
	}
	// And at composition, whether or not the node holds the environment.
	r := Resolution{Node: "workstation", Account: "op", Modules: modules}
	if _, err := r.Declaration(Rendering{}); err == nil || !strings.Contains(err.Error(), "neovim and zsh both set EDITOR") {
		t.Fatalf("composition accepted a variable set twice: %v", err)
	}
}

// shells contributes code for several shells and slots, in no order.
func shells() []Manifest {
	return []Manifest{
		{Module: "zsh-syntax-highlighting", Shell: []ShellCode{
			{For: "zsh", Slot: "last", Code: "source /usr/share/zsh/plugins/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh"},
		}},
		{Module: "powerlevel10k", Shell: []ShellCode{
			{For: "zsh", Slot: "first", Code: "if [[ -r \"${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh\" ]]; then\n" +
				"  source \"${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh\"\nfi\n"},
			{For: "zsh", Slot: "normal", Code: "source ~/.local/share/powerlevel10k/powerlevel10k.zsh-theme"},
			{For: "zsh", Slot: "normal", Code: "[[ -f ~/.local/share/powerlevel10k/p10k.zsh ]] && source ~/.local/share/powerlevel10k/p10k.zsh"},
		}},
		{Module: "zsh-autosuggestions", Shell: []ShellCode{
			{For: "zsh", Slot: "normal", Code: "source /usr/share/zsh/plugins/zsh-autosuggestions/zsh-autosuggestions.zsh"},
			{For: "bash", Slot: "normal", Code: "echo not for zsh"},
		}},
		{Module: "direnv", Shell: []ShellCode{
			{For: "fish", Slot: "last", Code: "direnv hook fish | source"},
			{For: "bash", Slot: "last", Code: "eval \"$(direnv hook bash)\""},
		}},
	}
}

// ADR 0204 §3: a slot holds that shell's code only, in module order, each module's pieces in the
// order it declared them under a line naming it; empty when nothing is contributed.
func TestShellCodeLandsInItsSlotInModuleOrderForItsShellOnly(t *testing.T) {
	if got, want := shellCode(shells(), "zsh", "normal"), "# powerlevel10k\n"+
		"source ~/.local/share/powerlevel10k/powerlevel10k.zsh-theme\n"+
		"[[ -f ~/.local/share/powerlevel10k/p10k.zsh ]] && source ~/.local/share/powerlevel10k/p10k.zsh\n"+
		"# zsh-autosuggestions\n"+
		"source /usr/share/zsh/plugins/zsh-autosuggestions/zsh-autosuggestions.zsh\n"; got != want {
		t.Fatalf("zsh's normal slot is\n%s\nnot\n%s", got, want)
	}
	if got, want := shellCode(shells(), "zsh", "last"), "# zsh-syntax-highlighting\n"+
		"source /usr/share/zsh/plugins/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh\n"; got != want {
		t.Fatalf("zsh's last slot is\n%s\nnot\n%s", got, want)
	}
	if got, want := shellCode(shells(), "bash", "last"), "# direnv\neval \"$(direnv hook bash)\"\n"; got != want {
		t.Fatalf("bash's last slot is %q, not %q", got, want)
	}
	if got := shellCode(shells(), "fish", "first"); got != "" {
		t.Fatalf("a slot nobody contributed to holds %q", got)
	}
}

// The holder of node-login-shell, as WP3's zsh module writes its block, with its own zsh around the
// slots — which holds `${…}` of the shell's own that no mesh pass may touch either.
func zshHolder() Manifest {
	return Manifest{Module: "zsh", Claims: []Claim{{Name: LoginShellSeat, Scope: ScopeNode}},
		Resources: []map[string]any{
			{"id": "zshrc", "type": "file", "path": "${machine:account-home}/.zshrc", "content": "" +
				"${shell:zsh:first}" +
				"PROMPT='%n@%m ${PWD/#$HOME/~} '\n" +
				"${shell:zsh:normal}" +
				"alias ll='ls -l'\n" +
				"${shell:zsh:last}"},
		}}
}

// The case the ordering exists for: contributed zsh code full of `${…}` reaches the file byte for
// byte, because the shell's code is placed after every other placeholder pass and in one pass — a
// scanner for the mesh's placeholders that ran after it would read `${XDG_CACHE_HOME:-…}` and
// `${(%):-%n}` as the mesh's, or fill a `${machine:…}` some module wrote for its shell to see.
func TestShellCodeReachesTheHoldersFileByteForByte(t *testing.T) {
	modules := append(shells(), zshHolder(), Manifest{Module: "sly", Shell: []ShellCode{
		{For: "zsh", Slot: "last", Code: "echo ${machine:account-home} ${secret:x} ${shell:zsh:first} ${environment:posix}"},
	}})
	r := Resolution{Node: "workstation", Account: "op", Modules: modules}
	out, err := r.Declaration(Rendering{})
	if err != nil {
		t.Fatal(err)
	}
	var zshrc map[string]any
	for _, res := range out {
		if res["id"] == "zsh.zshrc" {
			zshrc = res
		}
	}
	if zshrc == nil {
		t.Fatalf("the holder's file was not composed: %v", out)
	}
	if zshrc["path"] != "/home/op/.zshrc" {
		t.Fatalf("the holder's own placeholders were not filled first: %v", zshrc["path"])
	}
	want := "# powerlevel10k\n" +
		"if [[ -r \"${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh\" ]]; then\n" +
		"  source \"${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh\"\nfi\n" +
		"PROMPT='%n@%m ${PWD/#$HOME/~} '\n" +
		"# powerlevel10k\n" +
		"source ~/.local/share/powerlevel10k/powerlevel10k.zsh-theme\n" +
		"[[ -f ~/.local/share/powerlevel10k/p10k.zsh ]] && source ~/.local/share/powerlevel10k/p10k.zsh\n" +
		"# zsh-autosuggestions\n" +
		"source /usr/share/zsh/plugins/zsh-autosuggestions/zsh-autosuggestions.zsh\n" +
		"alias ll='ls -l'\n" +
		"# sly\n" +
		"echo ${machine:account-home} ${secret:x} ${shell:zsh:first} ${environment:posix}\n" +
		"# zsh-syntax-highlighting\n" +
		"source /usr/share/zsh/plugins/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh\n"
	if got := zshrc["content"]; got != want {
		t.Fatalf("the holder's .zshrc is\n%s\nnot\n%s", got, want)
	}
}

// The holder of node-environment places both renderings, and they are the same as rendered alone.
func TestTheEnvironmentHolderPlacesBothRenderings(t *testing.T) {
	holder := Manifest{Module: "node-env", Claims: []Claim{{Name: EnvironmentSeat, Scope: ScopeNode}},
		Resources: []map[string]any{
			{"id": "posix", "type": "file", "path": "${machine:account-home}/.config/mesh/environment.sh",
				"content": "# The mesh's environment.\n${environment:posix}"},
			{"id": "systemd", "type": "file", "path": "${machine:account-home}/.config/environment.d/50-mesh.conf",
				"content": "${environment:systemd}"},
		}}
	r := Resolution{Node: "workstation", Account: "op", Modules: append(contributors(), holder)}
	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 by["node-env.posix"] != "# The mesh's environment.\n"+composedPOSIX {
		t.Fatalf("the POSIX file is\n%v", by["node-env.posix"])
	}
	if by["node-env.systemd"] != composedSystemd {
		t.Fatalf("the environment.d file is\n%v", by["node-env.systemd"])
	}
}

// ADR 0203 §5 and ADR 0204 §3: a placeholder outside the seat's holder is refused — by the parser,
// which is what the catalogue check and registration run, and again at composition, in the same words.
func TestAPlaceholderOutsideTheHolderIsRefused(t *testing.T) {
	for _, c := range []struct{ content, want string }{
		{"${environment:posix}", "toolchain's resource rc names ${environment:posix} and toolchain does not claim node-environment"},
		{"${shell:zsh:normal}", "toolchain's resource rc names ${shell:zsh:normal} and toolchain does not claim node-login-shell"},
	} {
		raw := `{"module":"toolchain","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("the catalogue check accepted %s outside its holder: %v", c.content, err)
		}
		m := Manifest{Module: "toolchain", Resources: []map[string]any{
			{"id": "rc", "type": "file", "path": "/etc/rc", "content": c.content}}}
		r := Resolution{Node: "workstation", Account: "op", Modules: []Manifest{m}}
		if _, err := r.Declaration(Rendering{}); err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("composition accepted %s outside its holder: %v", c.content, err)
		}
	}
}

// A key nobody renders is refused, not left in the file as a literal.
func TestAnUnknownPlaceholderKeyIsRefused(t *testing.T) {
	for _, c := range []struct{ content, want string }{
		{"${environment:foo}", "names ${environment:foo}; the environment is ${environment:posix} or ${environment:systemd}"},
		{"${shell:zsh:middle}", "names ${shell:zsh:middle}; shell code is ${shell:<shell>:<slot>}"},
		{"${shell:tcsh:first}", "names ${shell:tcsh:first}; shell code is ${shell:<shell>:<slot>}"},
		{"${shell:zsh}", "names ${shell:zsh}; shell code is ${shell:<shell>:<slot>}"},
	} {
		raw := `{"module":"holder","claims":[{"name":"node-environment","scope":"node"},{"name":"node-login-shell","scope":"node"}],` +
			`"resources":[{"id":"rc","type":"file","path":"/etc/rc","content":"` + c.content + `"}]}`
		if _, err := ParseManifest([]byte(raw)); err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("%s was accepted: %v", c.content, err)
		}
	}
	// And outside a file's content, where nothing could be placed.
	raw := `{"module":"holder","claims":[{"name":"node-environment","scope":"node"}],` +
		`"resources":[{"id":"rc","type":"file","path":"/etc/${environment:posix}","content":"x"}]}`
	if _, err := ParseManifest([]byte(raw)); err == nil ||
		!strings.Contains(err.Error(), "names ${environment:posix} in its path; the environment and the shell's code are placed only in a file's content") {
		t.Errorf("a placeholder in a path was accepted: %v", err)
	}
}

// What ADR 0203 §2 allows a contribution to say, refused at parse when it says anything else.
func TestAMalformedEnvironmentIsRefusedAtParse(t *testing.T) {
	for _, c := range []struct{ environment, want string }{
		{`{"variables":{"1X":"a"}}`, `tool sets the variable "1X", which is not a name a shell accepts`},
		{`{"variables":{"MY-VAR":"a"}}`, `tool sets the variable "MY-VAR", which is not a name a shell accepts`},
		{`{"variables":{"PATH":"/bin"}}`, `tool sets PATH as a variable; a module adds an entry under environment.path`},
		{`{"variables":{"A":"$HOME/x"}}`, `tool sets A to "$HOME/x", which holds a $ that is not one of the machine's ${machine:…} facts`},
		{`{"variables":{"A":"${HOME}/x"}}`, `tool sets A to "${HOME}/x", which holds a $`},
		{`{"variables":{"A":"it's"}}`, `tool sets A to "it's", which holds a quote`},
		{`{"variables":{"A":"say \"hi\""}}`, `which holds a quote`},
		{`{"variables":{"A":"a\\b"}}`, `which holds a backslash`},
		{`{"variables":{"A":"a\nb"}}`, `which holds a line break`},
		{`{"variables":{"A":"a\u0000b"}}`, `which holds a NUL`},
		{`{"path":[{"entry":"","at":"start"}]}`, `tool's PATH entry 1 names no directory`},
		{`{"path":[{"entry":"/a:/b","at":"start"}]}`, `tool puts "/a:/b" on PATH, which holds a colon`},
		{`{"path":[{"entry":"$HOME/bin","at":"start"}]}`, `tool puts "$HOME/bin" on PATH, which holds a $`},
		{`{"path":[{"entry":"/a","at":"middle"}]}`, `tool puts "/a" on PATH at "middle"; an entry goes at "start" or "end"`},
		{`{"path":[{"entry":"/a"}]}`, `tool puts "/a" on PATH at ""`},
		{`{"path":[{"entry":"/a","at":"start"},{"entry":"/a","at":"end"}]}`, `tool puts "/a" on PATH twice`},
		{`{"variables":{"A":"x"},"paths":[]}`, `unknown field "paths"`},
	} {
		_, err := ParseManifest([]byte(`{"module":"tool","environment":` + c.environment + `}`))
		if err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("%s: want %q, got %v", c.environment, c.want, err)
		}
	}
	// What is allowed: a literal, and the machine's own facts.
	if _, err := ParseManifest([]byte(`{"module":"tool","environment":{` +
		`"variables":{"GOPATH":"${machine:account-home}/go","DISABLE_X":"1","ANSWER":"a b+c=d"},` +
		`"path":[{"entry":"${machine:account-home}/go/bin","at":"start"},{"entry":"/opt/x","at":"end"}]}}`)); err != nil {
		t.Fatalf("a well-formed environment was refused: %v", err)
	}
}

func TestMalformedShellCodeIsRefusedAtParse(t *testing.T) {
	for _, c := range []struct{ shell, want string }{
		{`[{"for":"tcsh","slot":"normal","code":"x"}]`, `tool's shell code 1 is for "tcsh"; the shells are zsh, bash, fish`},
		{`[{"for":"zsh","slot":"middle","code":"x"}]`, `tool's shell code 1 goes in the slot "middle"; the slots are first, normal, last`},
		{`[{"for":"zsh","slot":"last","code":"x"},{"for":"zsh","slot":"last","code":" \n"}]`, `tool's shell code 2 has no code`},
		{`[{"for":"zsh","slot":"last","code":"x","order":1}]`, `unknown field "order"`},
	} {
		_, err := ParseManifest([]byte(`{"module":"tool","shell":` + c.shell + `}`))
		if err == nil || !strings.Contains(err.Error(), c.want) {
			t.Errorf("%s: want %q, got %v", c.shell, c.want, err)
		}
	}
	// The code itself is never judged: a shell's own `${…}` is not the mesh's.
	if _, err := ParseManifest([]byte(`{"module":"tool","shell":[{"for":"zsh","slot":"first",` +
		`"code":"source \"${XDG_CACHE_HOME:-$HOME/.cache}/p10k-instant-prompt-${(%):-%n}.zsh\""}]}`)); err != nil {
		t.Fatalf("shell code was judged as if it were the mesh's: %v", err)
	}
}

// ADR 0203 §1 and ADR 0204 §1: both seats are the mesh's own, held once per machine; the login
// shell's contract is `execute`, described and with a schema an agent can call.
func TestTheSeatTableCarriesTheEnvironmentAndTheLoginShell(t *testing.T) {
	env, ok := SeatNamed("node-environment")
	if !ok || env.Scope != ScopeNode || env.Decision != "novox/hq ADR 0203" ||
		len(env.Serves)+len(env.Accepts)+len(env.Emits) != 0 || env.Delivers != "" {
		t.Fatalf("node-environment is not a node seat with no protocol: %+v (defined %v)", env, ok)
	}
	shell, ok := SeatNamed("node-login-shell")
	if !ok || shell.Scope != ScopeNode || shell.Decision != "novox/hq ADR 0204" {
		t.Fatalf("node-login-shell is not a node seat: %+v (defined %v)", shell, ok)
	}
	if len(shell.Serves) != 1 || shell.Serves[0].Name != "execute" || shell.Serves[0].Description == "" {
		t.Fatalf("the login shell serves %+v, not execute alone", shell.Serves)
	}
	props, _ := shell.Serves[0].Input["properties"].(map[string]any)
	required, _ := shell.Serves[0].Input["required"].([]string)
	if _, has := props["command"]; !has || len(required) != 1 || required[0] != "command" {
		t.Fatalf("execute does not require a command: %v", shell.Serves[0].Input)
	}
	if _, has := props["timeout_seconds"]; !has {
		t.Fatalf("execute takes no timeout: %v", props)
	}
}

// ADR 0204 §1: the login shell is the mesh's, so no module declares it — neither under the mesh's
// name nor under the name a module gave it before.
func TestNoModuleMayDeclareTheLoginShell(t *testing.T) {
	for _, n := range []string{"login-shell", "node-login-shell", "node-environment"} {
		raw := `{"module":"zsh","seats":[{"name":"` + n + `","scope":"node","serves":["execute"]}],"tools":["execute"]}`
		_, err := ParseManifest([]byte(raw))
		if err == nil {
			t.Errorf("a module declaring %q was accepted", n)
		}
	}
	got := strings.Join(declaredSeatProblems(Manifest{Module: "zsh",
		DefinesSeats: []SeatDeclaration{{Name: "login-shell", Scope: ScopeNode}}}), "; ")
	if !strings.Contains(got, `zsh declares a seat named "login-shell"; the login shell is the mesh's own seat node-login-shell`) {
		t.Fatalf("declaring login-shell was not refused by name: %q", got)
	}
	// And a shell module claiming the mesh's seat, serving execute, is what the seat is for.
	m, err := ParseManifest([]byte(`{"module":"zsh","tools":["execute"],` +
		`"claims":[{"name":"node-login-shell","scope":"node"}]}`))
	if err != nil {
		t.Fatal(err)
	}
	if err := CanHold(m, Seat{Name: LoginShellSeat, Scope: ScopeNode, Serves: loginShellVerbs()}); err != nil {
		t.Fatalf("a shell module claiming the seat cannot hold it: %v", err)
	}
}