// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause

package taildrop

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

// Tests "foo.jpg.deleted" marks (for Windows).
func TestDeletedMarkers(t *testing.T) {
	dir := t.TempDir()
	h := &Handler{RootDir: dir}

	nothingWaiting := func() {
		t.Helper()
		h.knownEmpty.Store(false)
		if h.HasFilesWaiting() {
			t.Fatal("unexpected files waiting")
		}
	}
	touch := func(base string) {
		t.Helper()
		if err := TouchFile(filepath.Join(dir, base)); err != nil {
			t.Fatal(err)
		}
	}
	wantEmptyTempDir := func() {
		t.Helper()
		if fis, err := os.ReadDir(dir); err != nil {
			t.Fatal(err)
		} else if len(fis) > 0 && runtime.GOOS != "windows" {
			for _, fi := range fis {
				t.Errorf("unexpected file in tempdir: %q", fi.Name())
			}
		}
	}

	nothingWaiting()
	wantEmptyTempDir()

	touch("foo.jpg.deleted")
	nothingWaiting()
	wantEmptyTempDir()

	touch("foo.jpg.deleted")
	touch("foo.jpg")
	nothingWaiting()
	wantEmptyTempDir()

	touch("foo.jpg.deleted")
	touch("foo.jpg")
	wf, err := h.WaitingFiles()
	if err != nil {
		t.Fatal(err)
	}
	if len(wf) != 0 {
		t.Fatalf("WaitingFiles = %d; want 0", len(wf))
	}
	wantEmptyTempDir()

	touch("foo.jpg.deleted")
	touch("foo.jpg")
	if rc, _, err := h.OpenFile("foo.jpg"); err == nil {
		rc.Close()
		t.Fatal("unexpected foo.jpg open")
	}
	wantEmptyTempDir()

	// And verify basics still work in non-deleted cases.
	touch("foo.jpg")
	touch("bar.jpg.deleted")
	if wf, err := h.WaitingFiles(); err != nil {
		t.Error(err)
	} else if len(wf) != 1 {
		t.Errorf("WaitingFiles = %d; want 1", len(wf))
	} else if wf[0].Name != "foo.jpg" {
		t.Errorf("unexpected waiting file %+v", wf[0])
	}
	if rc, _, err := h.OpenFile("foo.jpg"); err != nil {
		t.Fatal(err)
	} else {
		rc.Close()
	}
}