[Golang] Find Last Modified File Before Specific Time

package main

import (
      "fmt"
      "path/filepath"
      "time"
)

func FindLastModifiedFileBefore(dir string, t time.Time) (path string, info os.FileInfo, err error) {
      isFirst := true
      min := 0 * time.Second
      err = filepath.Walk(dir, func(p string, i os.FileInfo, e error) error {
              if e != nil {
                      return e
              }

              if !i.IsDir() && i.ModTime().Before(t) {
                      if isFirst {
                              isFirst = false
                              path = p
                              info = i
                              min = t.Sub(i.ModTime())
                      }
                      if diff := t.Sub(i.ModTime()); diff < min {
                              path = p
                              min = diff
                              info = i
                      }
              }
              return nil
      })
      return
}

func main() {
      dir := "/path/to/your/dir"
      path, info, err := FindLastModifiedFileBefore(dir, time.Now())
      if err != nil {
              panic(err)
      }
      fmt.Println(path)
      fmt.Println(info)
}