package agent

import (
	"archive/tar"
	"bytes"
	"io"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"
)

func TestParseStatLine(t *testing.T) {
	// statCommand prints: type|size|mtime|mode|name
	e, ok := parseStatLine("directory|4096|1760000000|drwxr-xr-x|my dir")
	if !ok || !e.IsDir || e.Name != "my dir" || e.MTime != 1760000000 || e.Mode != "drwxr-xr-x" {
		t.Fatalf("dir: %+v %v", e, ok)
	}
	e, ok = parseStatLine("regular file|12|1760000001|-rw-r--r--|a|b.txt")
	if !ok || e.IsDir || e.Size != 12 || e.Name != "a|b.txt" {
		t.Fatalf("file with | in name: %+v %v", e, ok)
	}
	if _, ok := parseStatLine("garbage"); ok {
		t.Fatal("garbage parsed")
	}
}

func TestStatCommandQuotes(t *testing.T) {
	for _, fl := range []string{"gnu", "bsd"} {
		c := statCommand(fl, "/srv/it's here")
		if !strings.Contains(c, `'/srv/it'\''s here/'`) {
			t.Errorf("%s: dir not quoted: %s", fl, c)
		}
	}
}

func TestParseLsLine(t *testing.T) {
	e, ok := parseLsLine("-rw-r--r--  1 root root  1234 Oct 15 10:00 my file.txt")
	if !ok || e.Name != "my file.txt" || e.Size != 1234 || e.IsDir {
		t.Fatalf("file: %+v %v", e, ok)
	}
	e, ok = parseLsLine("lrwxrwxrwx  1 root root     7 Oct 15 10:00 link -> target")
	if !ok || e.Name != "link" {
		t.Fatalf("link: %+v %v", e, ok)
	}
	if _, ok := parseLsLine("drwxr-xr-x  2 root root  4096 Oct 15 10:00 .."); ok {
		t.Fatal(".. listed")
	}
	if _, ok := parseLsLine("total 8"); ok {
		t.Fatal("total parsed")
	}
}

func TestRenameTarEntries(t *testing.T) {
	var src bytes.Buffer
	tw := tar.NewWriter(&src)
	for _, n := range []string{"old/", "old/a.txt", "old/sub/b"} {
		typ := byte(tar.TypeReg)
		if strings.HasSuffix(n, "/") {
			typ = tar.TypeDir
		}
		_ = tw.WriteHeader(&tar.Header{Name: n, Mode: 0o644, Typeflag: typ})
	}
	_ = tw.Close()
	var out bytes.Buffer
	if err := renameTar(&out, &src, map[string]string{"old": "new"}); err != nil {
		t.Fatal(err)
	}
	tr := tar.NewReader(&out)
	var names []string
	for {
		h, err := tr.Next()
		if err != nil {
			break
		}
		names = append(names, h.Name)
	}
	if strings.Join(names, ",") != "new/,new/a.txt,new/sub/b" {
		t.Fatalf("names: %v", names)
	}
}

// A macOS host's tar packs "._name" companions with the file's attributes;
// they are not the file and must not land under its name.
func TestRenameTarDropsOtherEntries(t *testing.T) {
	var src bytes.Buffer
	tw := tar.NewWriter(&src)
	for _, e := range []struct{ n, body string }{{"./._r.txt", "attrs"}, {"./r.txt", "data"}} {
		_ = tw.WriteHeader(&tar.Header{Name: e.n, Mode: 0o644, Typeflag: tar.TypeReg, Size: int64(len(e.body))})
		_, _ = tw.Write([]byte(e.body))
	}
	_ = tw.Close()
	var out bytes.Buffer
	if err := renameTar(&out, &src, map[string]string{"r.txt": "new.txt"}); err != nil {
		t.Fatal(err)
	}
	tr := tar.NewReader(&out)
	var got []string
	for {
		h, err := tr.Next()
		if err != nil {
			break
		}
		b, _ := io.ReadAll(tr)
		got = append(got, h.Name+"="+string(b))
	}
	if strings.Join(got, ",") != "new.txt=data" {
		t.Fatalf("entries: %v", got)
	}
}

// zip on an SSH host: from the items' folder, by their own names, quoted.
func TestZipCommand(t *testing.T) {
	cmd, err := zipCommand([]string{"/srv/a b", "/srv/it's"}, "/tmp/x.zip")
	if err != nil {
		t.Fatal(err)
	}
	want := `cd -- '/srv' && if command -v zip >/dev/null 2>&1; then zip -r -q -y '/tmp/x.zip' './a b' './it'\''s'; ` +
		`else python3 -m zipfile -c '/tmp/x.zip' './a b' './it'\''s'; fi`
	if cmd != want {
		t.Fatalf("got  %s\nwant %s", cmd, want)
	}
	if _, err := zipCommand([]string{"/a/x", "/b/y"}, "/t.zip"); err == nil {
		t.Fatal("items of two folders: want an error")
	}
	if _, err := zipCommand(nil, "/t.zip"); err == nil {
		t.Fatal("no items: want an error")
	}
	if got := unzipCommand("/srv/a.zip", ""); got != `if command -v unzip >/dev/null 2>&1; then unzip -o -q '/srv/a.zip' -d '/srv'; else python3 -m zipfile -e '/srv/a.zip' '/srv'; fi` {
		t.Fatalf("unzip: %s", got)
	}
}

// A connection busy with a long transfer is not idle, however long ago it
// was opened; once the transfer ends the idle clock starts again.
func TestSweepSparesBusyConn(t *testing.T) {
	c := &sshfsConn{last: time.Now().Add(-2 * sshfsIdle)}
	release := c.hold()
	if c.idle(time.Now()) {
		t.Fatal("a busy connection was taken for idle")
	}
	release()
	if c.idle(time.Now()) {
		t.Fatal("just released: not idle yet")
	}
	if !c.idle(time.Now().Add(2 * sshfsIdle)) {
		t.Fatal("unused for long: idle")
	}
}

// A file's size is its target's when it is a link: what cat will read.
func TestSizeCommandFollowsLinks(t *testing.T) {
	for _, f := range []string{"gnu", "bsd"} {
		if cmd := sizeCommand(f, "/x"); !strings.Contains(cmd, "stat -L ") {
			t.Fatalf("%s: %s", f, cmd)
		}
	}
}

// Nothing of a tar stream lands outside name: other entries and ".." paths
// are dropped.
func TestRenameTarKeepsInsideName(t *testing.T) {
	var src bytes.Buffer
	tw := tar.NewWriter(&src)
	for _, n := range []string{"d/a", "d/../../etc/x", ".ssh/authorized_keys", "d/b"} {
		_ = tw.WriteHeader(&tar.Header{Name: n, Mode: 0o644, Typeflag: tar.TypeReg})
	}
	_ = tw.Close()
	var out bytes.Buffer
	if err := renameTar(&out, &src, map[string]string{"d": "d"}); err != nil {
		t.Fatal(err)
	}
	tr := tar.NewReader(&out)
	var got []string
	for {
		h, err := tr.Next()
		if err != nil {
			break
		}
		got = append(got, h.Name)
	}
	if strings.Join(got, ",") != "d/a,d/b" {
		t.Fatalf("entries: %v", got)
	}
}

// Into an SSH host, "replace" replaces the thing whole, as on a machine.
func TestUnpackCommandReplaces(t *testing.T) {
	cmd := unpackCommand("/srv", []string{"d"}, "replace")
	if !strings.HasPrefix(cmd, "rm -rf -- '/srv/d' && ") || strings.Contains(cmd, "--overwrite") {
		t.Fatalf("replace: %s", cmd)
	}
	if cmd := unpackCommand("/srv", []string{"d"}, "error"); cmd != "mkdir -p -- '/srv' && cd -- '/srv' && tar -xf -" {
		t.Fatalf("error: %s", cmd)
	}
}

// A link to a folder lists as a folder (marked as a link), so it opens.
func TestParseStatLineFolderLink(t *testing.T) {
	e, ok := parseStatLine("LD|symbolic link|7|1700000000|lrwxrwxrwx|www")
	if !ok || !e.IsDir || !e.Link || e.Name != "www" {
		t.Fatalf("%+v %v", e, ok)
	}
	e, ok = parseStatLine("|regular file|5|1700000000|-rw-r--r--|a|b")
	if !ok || e.IsDir || e.Name != "a|b" {
		t.Fatalf("plain: %+v %v", e, ok)
	}
	if !strings.Contains(statCommand("gnu", "/x"), `[ -L "$f" ] && [ -d "$f" ]`) {
		t.Fatal("the command does not mark folder links")
	}
}

func TestListFolderLink(t *testing.T) {
	d := t.TempDir()
	_ = os.Mkdir(filepath.Join(d, "real"), 0o755)
	_ = os.Symlink(filepath.Join(d, "real"), filepath.Join(d, "ln"))
	r, err := fsList(d)
	if err != nil {
		t.Fatal(err)
	}
	for _, e := range r.Entries {
		if e.Name == "ln" && (!e.IsDir || !e.Link) {
			t.Fatalf("link: %+v", e)
		}
	}
}

// Commands go to the host as one argument of sh -c, so the user's own login
// shell (fish, csh) cannot read them its way.
func TestPosixCommand(t *testing.T) {
	if got := posix(`if [ -d '/x' ]; then echo ok; fi`); got != `sh -c 'if [ -d '\''/x'\'' ]; then echo ok; fi'` {
		t.Fatalf("%s", got)
	}
}

// csh expands "!" even inside single quotes: it goes out as '\!'.
func TestPosixCommandBang(t *testing.T) {
	if got := posix(`ls .[!.]*`); got != `sh -c 'ls .['\!'.]*'` {
		t.Fatalf("%s", got)
	}
}