package tempdir

import (
	"os"
	"path/filepath"
	"runtime"
	"testing"
)

func TestOutsideHonorsRelativeTemporaryDirectory(t *testing.T) {
	parent := t.TempDir()
	repository := t.TempDir()
	cwd, err := os.Getwd()
	if err != nil {
		t.Fatal(err)
	}
	relative, err := filepath.Rel(cwd, parent)
	if err != nil {
		t.Skip("temporary directory is on another volume")
	}
	setTemporaryDirectory(t, relative)
	directory, err := Outside(repository, "fixture-")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(directory)
	if !filepath.IsAbs(directory) || filepath.Dir(directory) != parent {
		t.Fatalf("temporary storage=%q want parent %q", directory, parent)
	}
}

func TestOutsideFallsBackWhenTemporaryDirectoryIsInsideWorktree(t *testing.T) {
	parent := t.TempDir()
	repository := filepath.Join(parent, "worktree")
	if err := os.Mkdir(repository, 0o700); err != nil {
		t.Fatal(err)
	}
	localTemporary := filepath.Join(repository, "tmp")
	if err := os.Mkdir(localTemporary, 0o700); err != nil {
		t.Fatal(err)
	}
	setTemporaryDirectory(t, localTemporary)
	directory, err := Outside(repository, "fixture-")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(directory)
	if filepath.Dir(directory) != parent {
		t.Fatalf("temporary storage=%q want external parent %q", directory, parent)
	}
	remaining, err := os.ReadDir(repository)
	if err != nil || len(remaining) != 1 || remaining[0].Name() != "tmp" {
		t.Fatalf("temporary storage left behind in worktree: %v %v", remaining, err)
	}
}

func setTemporaryDirectory(t *testing.T, directory string) {
	t.Helper()
	variable := "TMPDIR"
	if runtime.GOOS == "windows" {
		variable = "TMP"
	}
	t.Setenv(variable, directory)
}