package mount

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

func TestSetupAndTeardownWithFakeCommands(t *testing.T) {
	dir := t.TempDir()
	scripts := filepath.Join(dir, "bin")
	if err := os.MkdirAll(scripts, 0o755); err != nil {
		t.Fatal(err)
	}
	write := func(name, body string) {
		path := filepath.Join(scripts, name)
		if err := os.WriteFile(path, []byte("#!/usr/bin/env bash\nset -eu\n"+body+"\n"), 0o755); err != nil {
			t.Fatalf("write %s: %v", name, err)
		}
	}
	write("losetup", `printf '/dev/loop9\n'`)
	write("mount", `exit 0`)
	write("umount", `exit 0`)
	t.Setenv("PATH", scripts+string(os.PathListSeparator)+os.Getenv("PATH"))

	image := filepath.Join(dir, "image.img")
	if err := os.WriteFile(image, make([]byte, 1024), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(image+"p1", []byte(""), 0o644); err != nil {
		t.Fatal(err)
	}
	if got := partitionPath(image, 1); got != image+"p1" {
		t.Fatalf("partitionPath existing = %q", got)
	}
	m, err := Setup(image)
	if err != nil {
		t.Fatalf("Setup: %v", err)
	}
	if m.LoopDevice != "/dev/loop9" || m.BootPath == "" || m.RootPath == "" {
		t.Fatalf("unexpected mount: %#v", m)
	}
	if err := Teardown(m); err != nil {
		t.Fatalf("Teardown: %v", err)
	}
	if got := partitionPath("/dev/loop9", 2); got != "/dev/loop92" && got != "/dev/loop9p2" {
		t.Fatalf("partitionPath /dev = %q", got)
	}
}