package transfer

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

func TestReadFileRoundTrip(t *testing.T) {
	src := filepath.Join(t.TempDir(), "hello.txt")
	content := []byte("hello, clip-sync!")
	if err := os.WriteFile(src, content, 0644); err != nil {
		t.Fatalf("WriteFile: %v", err)
	}

	f, err := ReadFile(src, "machine-a")
	if err != nil {
		t.Fatalf("ReadFile: %v", err)
	}
	if f.Name != "hello.txt" {
		t.Errorf("Name = %q, want \"hello.txt\"", f.Name)
	}
	if f.Mime != "text/plain; charset=utf-8" {
		t.Errorf("Mime = %q, want \"text/plain; charset=utf-8\"", f.Mime)
	}

	decoded, err := f.Decode()
	if err != nil {
		t.Fatalf("Decode: %v", err)
	}
	if string(decoded) != string(content) {
		t.Errorf("decoded = %q, want %q", decoded, content)
	}
}

func TestSaveTo(t *testing.T) {
	dir := t.TempDir()
	f := &File{Name: "out.bin", Mime: "application/octet-stream", Data: ""}
	// Data must be base64-encoded; use a known encoding of "abc".
	f.Data = "YWJj"

	dest, err := f.SaveTo(dir)
	if err != nil {
		t.Fatalf("SaveTo: %v", err)
	}
	got, err := os.ReadFile(dest)
	if err != nil {
		t.Fatalf("ReadFile: %v", err)
	}
	if string(got) != "abc" {
		t.Errorf("saved = %q, want \"abc\"", got)
	}
}

func TestSaveToAvoidsOverwrite(t *testing.T) {
	dir := t.TempDir()
	f := &File{Name: "out.bin", Data: "eA=="} // base64 "x"

	first, err := f.SaveTo(dir)
	if err != nil {
		t.Fatalf("first SaveTo: %v", err)
	}
	second, err := f.SaveTo(dir)
	if err != nil {
		t.Fatalf("second SaveTo: %v", err)
	}
	if first == second {
		t.Errorf("second save overwrote first: %q == %q", first, second)
	}
}

func TestSaveToSanitizesPath(t *testing.T) {
	dir := t.TempDir()
	f := &File{Name: "../../etc/passwd", Data: "eA=="}

	dest, err := f.SaveTo(dir)
	if err != nil {
		t.Fatalf("SaveTo: %v", err)
	}
	if filepath.Dir(dest) != dir {
		t.Errorf("dest dir = %q, want %q (path traversal not sanitized)", filepath.Dir(dest), dir)
	}
}