// Package service -----------------------------
// @file      : cron_delayDeleteFile.go
// @author    : JJXu
// @contact   : wavingbear@163.com
// @time      : 2023/9/4 9:16
// -------------------------------------------
package service

import (
	"fmt"
	"github.com/robfig/cron/v3"
	"os"
	"sort"
	"sync"
	"time"
)

// 延时删除文件
var DelayDeleteFileTask = new(delayDeleteFileTask)

type DelayDeleteFile struct {
	Path          string
	RetentionTime time.Time //保留时间
}
type delayDeleteFileTask struct {
	pendingDeleteFile []DelayDeleteFile
	locker            sync.Mutex
}

func (d *delayDeleteFileTask) AddTimerTask(c *cron.Cron) error {
	_, err := c.AddFunc("* * * * *", func() {
		d.Run()
	})
	return err
}
func (d *delayDeleteFileTask) AddPendingDeleteFile(files ...DelayDeleteFile) {
	d.locker.Lock()
	defer d.locker.Unlock()
	for _, f := range files {
		if d.fileExists(f.Path) {
			var now = time.Now()
			if f.RetentionTime.Before(now) {
				if d.deleteFile(f.Path) == nil {
					return
				}
			}
			d.pendingDeleteFile = append(d.pendingDeleteFile, f)
			if len(d.pendingDeleteFile) > 1 {
				sort.Slice(d.pendingDeleteFile, func(i, j int) bool {
					return d.pendingDeleteFile[i].RetentionTime.Before(d.pendingDeleteFile[j].RetentionTime)
				})
			}
		} else {
			fmt.Println("AddPendingDeleteFile: 文件不存在:" + f.Path)
		}
	}
}
func (d *delayDeleteFileTask) Run() error {
	d.locker.Lock()
	defer d.locker.Unlock()
	if len(d.pendingDeleteFile) == 0 {
		return nil
	}
	var now = time.Now()
	var tmpFile []DelayDeleteFile
	for i, f := range d.pendingDeleteFile {
		if f.RetentionTime.Before(now) {
			if d.deleteFile(f.Path) == nil {
				fmt.Println("文件已删除:" + f.Path)
			} else {
				tmpFile = append(tmpFile, d.pendingDeleteFile[i])
			}
		}
	}
	d.pendingDeleteFile = tmpFile

	return nil
}
func (d *delayDeleteFileTask) deleteFile(path string) error {
	if d.fileExists(path) {
		return os.RemoveAll(path)
	}

	return nil
}
func (d *delayDeleteFileTask) fileExists(path string) bool {
	// 检查路径是否存在
	_, err := os.Stat(path)
	if os.IsNotExist(err) {
		fmt.Printf("路径 %s 不存在\n", path)
		return false
	} else {
		return true
	}
}