package file

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

func TestCopy(t *testing.T) {
	contents := "COPY TEST"

	tmpDir, err := os.MkdirTemp(os.TempDir(), "go-common")
	if err != nil {
		t.Logf("could not create temp dir: %v", err)
		t.FailNow()
	}
	defer func() {
		if err := os.RemoveAll(tmpDir); err != nil {
			t.Logf("could not remove temp dir at %s: %v", tmpDir, err)
		}
	}()

	tmp1, err := setupCopy(tmpDir, contents)
	if err != nil {
		t.Log(err)
		t.FailNow()
	}

	tmp2 := filepath.Join(tmpDir, "tmp2")
	if err := Copy(tmp1, tmp2); err != nil {
		t.Logf("could not copy file: %v", err)
		t.FailNow()
	}

	b, err := os.ReadFile(tmp2)
	if err != nil {
		t.Logf("could not read tmp2: %v", err)
		t.FailNow()
	}

	if string(b) != contents {
		t.Logf("contents did not match")
		t.FailNow()
	}
}

func setupCopy(tmpDir, contents string) (string, error) {
	tmp, err := os.CreateTemp(tmpDir, "go-common")
	if err != nil {
		return "", fmt.Errorf("could not create temp file 1: %v", err)
	}
	if _, err := tmp.WriteString(contents); err != nil {
		return "", fmt.Errorf("could not write to temp file 1: %v", err)
	}
	return tmp.Name(), tmp.Close()
}