package apply

import (
	"context"
	"os"
	osuser "os/user"
	"path/filepath"
	"sort"
	"strings"
	"testing"

	"github.com/novox/mesh-host/internal/store"
)

// Defends novox/hq ADR 0182 and to-be 41: a parent the host makes inside an owner's home is the
// owner's, one that was there is held as found, and one outside the home is made as before.

// aHome gives the account running the test a home in a directory the test owns, and writes down
// every directory the host gives to whom. The account's own name, so what the host chowns resolves
// without being root; the record, so what was given is told apart from what was merely made.
func aHome(t *testing.T) (home, owner string, given map[string]string) {
	t.Helper()
	me, err := osuser.Current()
	if err != nil {
		t.Skip("no current user to own anything")
	}
	home = t.TempDir()
	given = map[string]string{}
	wasHome, wasOwn := homeOf, ownMade
	homeOf = func(name string) (string, error) {
		if name == me.Username {
			return home, nil
		}
		return wasHome(name)
	}
	ownMade = func(path, owner string) error {
		given[path] = owner
		return wasOwn(path, owner)
	}
	t.Cleanup(func() { homeOf, ownMade = wasHome, wasOwn })
	return home, me.Username, given
}

func givenPaths(given map[string]string) []string {
	var paths []string
	for p := range given {
		paths = append(paths, p)
	}
	sort.Strings(paths)
	return paths
}

func TestAFileUnderAHomeGivesTheParentsItMadeToItsOwner(t *testing.T) {
	home, owner, given := aHome(t)
	target := filepath.Join(home, ".config", "mesh", "environment.sh")
	d := parse(t, `{"declaration":1,"resources":[{"id":"shell.env","type":"file","path":"`+target+
		`","content":"export A=1\n","owner":"`+owner+`"}]}`)
	if _, _, err := Apply(context.Background(), archHost(t), d, store.State{}, store.OriginDeclared,
		noServices, nil, nil); err != nil {
		t.Fatal(err)
	}
	want := []string{filepath.Join(home, ".config"), filepath.Join(home, ".config", "mesh")}
	if got := givenPaths(given); strings.Join(got, ",") != strings.Join(want, ",") {
		t.Errorf("given to the owner: %v, want %v", got, want)
	}
	for _, p := range want {
		if given[p] != owner {
			t.Errorf("%s given to %q", p, given[p])
		}
	}
}

func TestAnArchiveUnderAHomeGivesTheParentsItMadeToItsOwner(t *testing.T) {
	home, owner, given := aHome(t)
	body, digest := anArchive(t, map[string]string{"p10k.zsh": "theme"})
	target := filepath.Join(home, ".local", "share", "powerlevel10k")
	d := declare(t, `{"id":"shell.theme","type":"archive","source":"`+serving(t, body)+
		`","digest":"`+digest+`","path":"`+target+`","owner":"`+owner+`"}`)
	if _, _, err := Apply(context.Background(), archHost(t), d, store.State{}, store.OriginDeclared,
		noServices, nil, nil); err != nil {
		t.Fatal(err)
	}
	for _, p := range []string{filepath.Join(home, ".local"), filepath.Join(home, ".local", "share")} {
		if given[p] != owner {
			t.Errorf("%s, made by the host, was not given to the owner: %v", p, givenPaths(given))
		}
	}
}

func TestAParentThatWasThereIsHeldAsFound(t *testing.T) {
	home, owner, given := aHome(t)
	config := filepath.Join(home, ".config")
	if err := os.Mkdir(config, 0o700); err != nil {
		t.Fatal(err)
	}
	target := filepath.Join(config, "mesh", "environment.sh")
	d := parse(t, `{"declaration":1,"resources":[{"id":"shell.env","type":"file","path":"`+target+
		`","content":"export A=1\n","owner":"`+owner+`"}]}`)
	if _, _, err := Apply(context.Background(), archHost(t), d, store.State{}, store.OriginDeclared,
		noServices, nil, nil); err != nil {
		t.Fatal(err)
	}
	if _, touched := given[config]; touched {
		t.Error("a parent that was already there was given to the owner")
	}
	if info, _ := os.Stat(config); info.Mode().Perm() != 0o700 {
		t.Errorf("a parent that was already there changed mode: %o", info.Mode().Perm())
	}
	if given[filepath.Join(config, "mesh")] != owner {
		t.Errorf("the parent the host made was not given to the owner: %v", givenPaths(given))
	}
}

func TestAParentOutsideTheHomeIsMadeAsBefore(t *testing.T) {
	_, owner, given := aHome(t)
	target := filepath.Join(t.TempDir(), "var", "lib", "module", "settings.conf")
	d := parse(t, `{"declaration":1,"resources":[{"id":"module.conf","type":"file","path":"`+target+
		`","content":"a=1\n","owner":"`+owner+`"}]}`)
	if _, _, err := Apply(context.Background(), archHost(t), d, store.State{}, store.OriginDeclared,
		noServices, nil, nil); err != nil {
		t.Fatal(err)
	}
	if len(given) != 0 {
		t.Errorf("parents outside the owner's home were given to it: %v", givenPaths(given))
	}
}