package ObsUtil

import (
	"dsSupport/Const"
	"dsSupport/Utils/ConfigUtil"
	"dsSupport/Utils/obs"
	"fmt"
	"net/http"
	"os"
	"time"
)

/**
功能：判断一个文件在OBS上是不是存在
作者：黄海
时间：2020-07-16
*/
func IsExist(key string) bool {
	_, err := http.Head("https://"+ConfigUtil.Endpoint+"/"+ConfigUtil.Bucket+"/"+Const.PreviewPrefix + key)
	if err != nil {
		return false
	}
	return true
}

/**
功能：删除指定前缀的过期文件
作者：黄海
时间：2020-04-05
*/
func DeleteExpireFile(prefix string, remainDays int32) {
	// 创建ObsClient结构体
	var obsClient, _ = obs.New(ConfigUtil.Ak, ConfigUtil.Sk, ConfigUtil.Endpoint)

	input := &obs.ListObjectsInput{}
	input.Bucket = ConfigUtil.Bucket
	// 设置列举带有prefix前缀的1000个对象
	input.MaxKeys = 1000
	input.Prefix = prefix

	output, err := obsClient.ListObjects(input)
	if err == nil {
		for index, val := range output.Contents {
			fmt.Printf("Content[%d]-OwnerId:%s, ETag:%s, Key:%s, LastModified:%s, Size:%d, StorageClass:%s\n",
				index, val.Owner.ID, val.ETag, val.Key, val.LastModified, val.Size, val.StorageClass)
			//判断是否过期
			now := time.Now()
			sumD := now.Sub(val.LastModified)
			if int32(sumD.Hours()/24) > remainDays {
				fmt.Println("发现超时文件，将删除:" + val.Key)
				input := &obs.DeleteObjectInput{}
				input.Bucket = ConfigUtil.Bucket
				input.Key = val.Key
				obsClient.DeleteObject(input)
				fmt.Println("已成功删除！" + val.Key)
			} else {
				fmt.Println("没有过期，无需删除:" + val.Key)
			}
		}
	} else if obsError, ok := err.(obs.ObsError); ok {
		fmt.Printf("Code:%s\n", obsError.Code)
		fmt.Printf("Message:%s\n", obsError.Message)
	}
	obsClient.Close()
}

/**
功能：上传本地文件到华为云存储
作者：黄海
时间：2020-04-05
*/
func UploadFileMultiPart(key string, sourceFile string) {
	// 创建ObsClient结构体
	var obsClient, _ = obs.New(ConfigUtil.Ak, ConfigUtil.Sk, ConfigUtil.Endpoint)
	// 初始化分段上传任务
	input := &obs.InitiateMultipartUploadInput{}
	input.Bucket = ConfigUtil.Bucket
	input.Key = key
	output, err := obsClient.InitiateMultipartUpload(input)
	if err != nil {
		panic(err)
	}
	uploadId := output.UploadId
	fmt.Printf("UploadId:%s\n", uploadId)
	fmt.Println()
	// 每段上传100MB
	var partSize int64 = 100 * 1024 * 1024
	stat, err := os.Stat(sourceFile)
	if err != nil {
		panic(err)
	}
	fileSize := stat.Size()
	// 计算需要上传的段数
	partCount := int(fileSize / partSize)
	if fileSize%partSize != 0 {
		partCount++
	}
	// 执行并发上传段
	partChan := make(chan obs.Part, 5)
	for i := 0; i < partCount; i++ {
		partNumber := i + 1
		offset := int64(i) * partSize
		currPartSize := partSize
		if i+1 == partCount {
			currPartSize = fileSize - offset
		}
		go func() {
			uploadPartInput := &obs.UploadPartInput{}
			uploadPartInput.Bucket = ConfigUtil.Bucket
			uploadPartInput.Key = key
			uploadPartInput.UploadId = uploadId
			uploadPartInput.SourceFile = sourceFile
			// 分段号
			uploadPartInput.PartNumber = partNumber
			// 分段在文件中的起始位置
			uploadPartInput.Offset = offset
			// 分段大小
			uploadPartInput.PartSize = currPartSize
			uploadPartInputOutput, err := obsClient.UploadPart(uploadPartInput)
			if err != nil {
				panic(err)
			}
			fmt.Printf("%d finished\n", partNumber)
			partChan <- obs.Part{ETag: uploadPartInputOutput.ETag, PartNumber: uploadPartInputOutput.PartNumber}
		}()
	}
	parts := make([]obs.Part, 0, partCount)
	// 等待上传完成
	for {
		part, ok := <-partChan
		if !ok {
			break
		}
		parts = append(parts, part)

		if len(parts) == partCount {
			close(partChan)
		}
	}
	completeMultipartUploadInput := &obs.CompleteMultipartUploadInput{}
	completeMultipartUploadInput.Bucket = ConfigUtil.Bucket
	completeMultipartUploadInput.Key = key
	completeMultipartUploadInput.UploadId = uploadId
	completeMultipartUploadInput.Parts = parts
	// 合并段
	completeMultipartUploadOutput, err := obsClient.CompleteMultipartUpload(completeMultipartUploadInput)
	if err != nil {
		panic(err)
	}
	fmt.Printf("RequestId:%s\n", completeMultipartUploadOutput.RequestId)
	obsClient.Close()
}