package folderwatcher

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"sync"
	"testing"
	"time"
)

func TestOldFilesInCreationOrder(t *testing.T) {
	tmpPath, err := os.MkdirTemp("", ".folderwatcher_test")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpPath)
	quitChan := make(chan struct{})

	filesIn := []string{"2", "C", "B", "A", "1"}
	makeAbsFilePaths(t, tmpPath, &filesIn)
	var filesOut []string

	wg := sync.WaitGroup{}

	conf := Config{
		Folder: tmpPath,
	}

	for _, f := range filesIn {
		wg.Add(1)
		_ = os.WriteFile(f, []byte{0}, os.ModePerm)
		time.Sleep(10 * time.Millisecond)
	}

	watcher, err := NewFolderWatcher(conf, true, quitChan)
	if err != nil {
		t.Fatal(err)
	}

	go watcher.Watch(func(filePath string) (bool, error) {
		if !filepath.IsAbs(filePath) {
			t.Errorf("file %s is not an absolute path", filePath)
		}
		filesOut = append(filesOut, filePath)
		wg.Done()
		return true, nil
	}, func(s string, err error) {
	})

	finishedChan := make(chan struct{})
	go func() {
		wg.Wait()
		finishedChan <- struct{}{}
	}()

	ctx, ctxCancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer ctxCancel()

	select {
	case <-finishedChan:
	case <-ctx.Done():
		t.Error(ctx.Err())
	}
	quitChan <- struct{}{}

	if len(filesOut) != len(filesIn) {
		t.Errorf("filesOut length %d != %d", len(filesOut), len(filesIn))
	}

	filesInS := fmt.Sprintf("%s", filesIn)
	filesOutS := fmt.Sprintf("%s", filesOut)
	if filesInS != filesOutS {
		t.Errorf("filesIn != filesOut %s != %s", filesIn, filesOut)
	}
}

func makeAbsFilePaths(t *testing.T, rootPath string, filesIn *[]string) {
	t.Helper()
	for i, f := range *filesIn { //remap filesIn to Full Path
		(*filesIn)[i] = filepath.Join(rootPath, f)
		if !filepath.IsAbs((*filesIn)[i]) {
			t.Fatalf("file %s is not an absolute path", (*filesIn)[i])
		}
	}
}