package resolution

import (
	"strings"
	"testing"

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

// 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() []mcat.Manifest {
	return []mcat.Manifest{
		{Module: "zsh", Environment: &mcat.Environment{
			Variables: map[string]string{"XDG_CONFIG_HOME": "${machine:account-home}/.config", "EDITOR": "vim"},
			Path: []mcat.PathEntry{
				{Entry: "${machine:account-home}/.local/bin", At: mcat.PathAtStart},
				{Entry: "${machine:account-home}/bin", At: mcat.PathAtStart},
				{Entry: "/opt/scripts", At: mcat.PathAtEnd},
			},
		}},
		{Module: "go-toolchain", Environment: &mcat.Environment{
			Variables: map[string]string{"GOPATH": "${machine:account-home}/go"},
			Path: []mcat.PathEntry{
				{Entry: "${machine:account-home}/go/bin", At: mcat.PathAtStart},
				{Entry: "/usr/local/go/bin", At: mcat.PathAtStart},
				{Entry: "${machine:account-home}/.local/bin", At: mcat.PathAtStart},
			},
		}},
		{Module: "agent", Environment: &mcat.Environment{
			Variables: map[string]string{"DISABLE_AUTOUPDATER": "1"},
			Path:      []mcat.PathEntry{{Entry: "/opt/agent/bin", At: mcat.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)
	}
}

// Nothing contributed renders nothing, in both formats — not an empty `export PATH`.
func TestNoContributionsRenderNothing(t *testing.T) {
	env, err := environmentOn([]mcat.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(), mcat.Manifest{Module: "neovim", Environment: &mcat.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 := mcat.Resolution{Node: "workstation", Account: "op", Modules: modules}
	if _, err := Declaration(r, mcat.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() []mcat.Manifest {
	return []mcat.Manifest{
		{Module: "zsh-syntax-highlighting", Shell: []mcat.ShellCode{
			{For: "zsh", Slot: "last", Code: "source /usr/share/zsh/plugins/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh"},
		}},
		{Module: "powerlevel10k", Shell: []mcat.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: []mcat.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: []mcat.ShellCode{
			{For: "fish", Slot: "last", Code: "direnv hook fish | source"},
			{For: "bash", Slot: "last", Code: "eval \"$(direnv hook bash)\""},
		}},
	}
}

// The holder of node-login-shell, as WP3's zsh module writes its block, with its own zsh around the
// slots — which holds `${…}` of the shell's own that no mesh pass may touch either.
func zshHolder() mcat.Manifest {
	return mcat.Manifest{Module: "zsh", Claims: []mcat.Claim{{Name: mcat.LoginShellSeat, Scope: mcat.ScopeNode}},
		Resources: []map[string]any{
			{"id": "zshrc", "type": "file", "path": "${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(), mcat.Manifest{Module: "sly", Shell: []mcat.ShellCode{
		{For: "zsh", Slot: "last", Code: "echo ${machine:account-home} ${secret:x} ${shell:zsh:first} ${environment:posix}"},
	}})
	r := mcat.Resolution{Node: "workstation", Account: "op", Modules: modules}
	out, err := Declaration(r, mcat.Rendering{})
	if err != nil {
		t.Fatal(err)
	}
	var zshrc map[string]any
	for _, res := range out {
		if res["id"] == "zsh.zshrc" {
			zshrc = res
		}
	}
	if zshrc == nil {
		t.Fatalf("the holder's file was not composed: %v", out)
	}
	if zshrc["path"] != "/home/op/.zshrc" {
		t.Fatalf("the holder's own placeholders were not filled first: %v", zshrc["path"])
	}
	want := "# powerlevel10k\n" +
		"if [[ -r \"${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 := mcat.Manifest{Module: "node-env", Claims: []mcat.Claim{{Name: mcat.EnvironmentSeat, Scope: mcat.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 := mcat.Resolution{Node: "workstation", Account: "op", Modules: append(contributors(), holder)}
	out, err := Declaration(r, mcat.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"])
	}
}