gopaper/files.go

package main

import (
	"math/rand"
	"os"
	"regexp"
)

func getRandomFile(dir string) (path string, filename string, error error) {
	files, err := os.ReadDir(dir)
	if err != nil {
		return "", "", err
	}

	// for _, file := range files { fmt.Println(file.Name(), file.IsDir())
	// }

	var randomIndex int
	var randomImg os.DirEntry
	for {
		randomIndex = rand.Intn(len(files))
		randomImg = files[randomIndex]
		//re-roll if you get a directory
		if files[randomIndex].IsDir() == false {
			break
		}
		//re-roll if not a recognised image type
		isImage, _ := regexp.Match(".jpg$|.jpeg$|.png$|.bmp$|.webp$", []byte(randomImg.Name()))
		if isImage {
			break
		}
	}
	return dir + "/" + randomImg.Name(), randomImg.Name(), nil
}

func fileExists(filename string) (bool, error) {
	files, err := os.ReadDir("images")
	if err != nil {
		return false, err
	}
	for _, file := range files {
		if file.Name() == filename {
			return true, nil
		}
	}
	return false, nil
}