package main

import (
    "context"
    "io"
    "os"
    "fmt"
    "encoding/json"
    "path/filepath"
    "sync"
    "strconv"
    "rabbitmq"
    "time"
    agentcaller "proto"

    //"github.com/pborman/uuid"
    //"github.com/streadway/amqp"

    "google.golang.org/grpc"

    _ "google.golang.org/grpc/balancer/grpclb"
)
const (
    port = ":5010"
    packetSizeInBytes=10
)

func Move(bucketName string, objectName string, destination string){
    //将bucketName, objectName, destination发给协调端
    fmt.Println("move "+bucketName+"/"+objectName+" to "+destination)
    //获取块hash，ip，序号，编码参数等
    //发送写请求，分配写入节点Ip 
    userId:=0
    command1:= rabbitmq.MoveCommand{
        BucketName: bucketName,
        ObjectName: objectName,
        UserId: userId,
        Destination: destination,
    }
    c1,_:=json.Marshal(command1)
    b1:=append([]byte("05"),c1...)
    fmt.Println(string(b1))
    rabbit1 := rabbitmq.NewRabbitMQSimple("coorQueue")
    rabbit1.PublishSimple(b1)

    //接收消息，赋值给ip, repHash, fileSizeInBytes
    var res1 rabbitmq.MoveRes
    var redundancy string
    var hashs []string
    var fileSizeInBytes int64
    var ecName string
    var ids []int
    queueName := "coorClientQueue"+strconv.Itoa(userId)
    rabbit2 := rabbitmq.NewRabbitMQSimple(queueName)
    msgs:=rabbit2.ConsumeSimple(time.Millisecond, true)
    wg := sync.WaitGroup{}
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res1)
            redundancy=res1.Redundancy
            ids=res1.Ids
            hashs=res1.Hashs
            fileSizeInBytes=res1.FileSizeInBytes
            ecName=res1.EcName
            wg.Done()
        }
    }()
    wg.Wait() 
    fmt.Println(redundancy)
    fmt.Println(hashs)
    fmt.Println(ids)
    fmt.Println(fileSizeInBytes)
    fmt.Println(ecName)
    //根据redundancy调用repMove和ecMove
    
    rabbit3 := rabbitmq.NewRabbitMQSimple("agentQueue"+destination)
    var b2 []byte
    switch redundancy {
        case "rep":
            command2:= rabbitmq.RepMoveCommand{
                Hashs: hashs,
                BucketName: bucketName,
                ObjectName: objectName,
                UserId: userId,
            }
            c2,_:=json.Marshal(command2) 
            b2=append([]byte("00"),c2...)
        case "ec":
            command2:= rabbitmq.EcMoveCommand{
                Hashs: hashs,
                Ids: ids,
                EcName: ecName,
                BucketName: bucketName,
                ObjectName: objectName,
                UserId: userId,
            }
            c2,_:=json.Marshal(command2)
            b2=append([]byte("01"),c2...)
    }
    fmt.Println(b2)
    rabbit3.PublishSimple(b2)
    //接受调度成功与否的消息
    //接受第二轮通讯结果
    var res2 rabbitmq.AgentMoveRes
    queueName = "agentClientQueue"+strconv.Itoa(userId)
    rabbit4 := rabbitmq.NewRabbitMQSimple(queueName)
    msgs=rabbit4.ConsumeSimple(time.Millisecond, true)
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res2)
            if(res2.MoveCode==0){
                wg.Done()
                fmt.Println("Move Success")
            }
        }
    }()
    wg.Wait()

    rabbit1.Destroy()
    rabbit2.Destroy()
    rabbit3.Destroy()
    rabbit4.Destroy()
}

func Read(localFilePath string, bucketName string, objectName string){
    fmt.Println("read "+bucketName+"/"+objectName+" to "+localFilePath)
    //获取块hash，ip，序号，编码参数等
    //发送写请求，分配写入节点Ip 
    userId:=0
    command1:= rabbitmq.ReadCommand{
        BucketName: bucketName,
        ObjectName: objectName,
        UserId: userId,
    }
    c1,_:=json.Marshal(command1)
    b1:=append([]byte("02"),c1...)
    fmt.Println(b1)
    rabbit1 := rabbitmq.NewRabbitMQSimple("coorQueue")
    rabbit1.PublishSimple(b1)

    //接收消息，赋值给ip, repHash, fileSizeInBytes
    var res1 rabbitmq.ReadRes
    var hashs []string
    var ips []string
    var fileSizeInBytes int64
    var ecName string
    var ids []int
    var redundancy string
    queueName := "coorClientQueue"+strconv.Itoa(userId)
    rabbit2 := rabbitmq.NewRabbitMQSimple(queueName)
    msgs:=rabbit2.ConsumeSimple(time.Millisecond, true)
    wg := sync.WaitGroup{}
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res1)
            ips=res1.Ips
	        hashs=res1.Hashs
	        ids=res1.BlockIds 
	        ecName=res1.EcName
	        fileSizeInBytes=res1.FileSizeInBytes
            redundancy=res1.Redundancy
            wg.Done()
        }
    }()
    wg.Wait() 
    fmt.Println(redundancy)
    fmt.Println(ips)
    fmt.Println(hashs)
    fmt.Println(ids)
    fmt.Println(ecName)
    fmt.Println(fileSizeInBytes)
    rabbit1.Destroy()
    rabbit2.Destroy()
    switch redundancy {
        case "rep":
            repRead(fileSizeInBytes, ips[0], hashs[0], localFilePath)
        case "ec":
            ecRead(fileSizeInBytes, ips, hashs, ids, ecName, localFilePath)
    }
    
}


func repRead(fileSizeInBytes int64, ip string, repHash string, localFilePath string){
    numPacket := (fileSizeInBytes+packetSizeInBytes-1)/(packetSizeInBytes)
    fmt.Println(numPacket)
    //rpc相关
    conn, err := grpc.Dial(ip+port, grpc.WithInsecure())
    if err != nil {
        panic(err)
    }
    client := agentcaller.NewTranBlockOrReplicaClient(conn) 

    fDir, err := os.Executable()
    if err != nil {
        panic(err)
    }
    fURL := filepath.Join(filepath.Dir(fDir), "assets")
    _, err = os.Stat(fURL)
    if os.IsNotExist(err) {
        os.MkdirAll(fURL, os.ModePerm)
    }

    file, err := os.Create(filepath.Join(fURL, localFilePath))
    if err != nil {
        return
    }
    
    stream, _ := client.GetBlockOrReplica(context.Background(), &agentcaller.GetReq{
		BlockOrReplicaHash: repHash,
	})
    fmt.Println(numPacket)
	for i:=0;int64(i)<numPacket;i++{
        fmt.Println(i)
		res, _:= stream.Recv()
	    fmt.Println(res.BlockOrReplicaData)
        file.Write(res.BlockOrReplicaData)
	}
    file.Close() 
    conn.Close()   
}

func RepWrite(localFilePath string, bucketName string, objectName string, numRep int){
    userId:=0
    //获取文件大小
    fileInfo,_ := os.Stat(localFilePath)
    fileSizeInBytes := fileInfo.Size()
    fmt.Println(fileSizeInBytes)

    //计算每个块的packet数
    numWholePacket := fileSizeInBytes/packetSizeInBytes
    lastPacketInBytes:=fileSizeInBytes%packetSizeInBytes
    numPacket:=numWholePacket
    if lastPacketInBytes>0 {
        numPacket++
    }

    //发送写请求，分配写入节点Ip 
    command1:= rabbitmq.RepWriteCommand{
        BucketName: bucketName,
        ObjectName: objectName,
        FileSizeInBytes: fileSizeInBytes,
        NumRep: numRep,
        UserId: userId,
    }
    c1,_:=json.Marshal(command1)
    b1:=append([]byte("03"),c1...)
    fmt.Println(b1)
    rabbit1 := rabbitmq.NewRabbitMQSimple("coorQueue")
    rabbit1.PublishSimple(b1)

    //接收消息，赋值给ips
    var res1 rabbitmq.WriteRes
    var ips []string
    queueName := "coorClientQueue"+strconv.Itoa(userId)
    rabbit2 := rabbitmq.NewRabbitMQSimple(queueName)
    msgs:=rabbit2.ConsumeSimple(time.Millisecond, true)
    wg := sync.WaitGroup{}
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res1)
            ips=res1.Ips
            wg.Done()
        }
    }()
    wg.Wait()    

    //创建channel
    loadDistributeBufs:=make([]chan []byte,numRep) 
    for i := 0; i < numRep; i++ {
        loadDistributeBufs[i] = make(chan []byte)
    }
    
    //正式开始写入
    hashs:= make([]string, numRep)
    go loadDistribute(localFilePath, loadDistributeBufs[:], numWholePacket, lastPacketInBytes)//从本地文件系统加载数据
    wg.Add(numRep)
    for i:=0;i<numRep;i++ {
        go send("rep.json"+strconv.Itoa(i), ips[i], loadDistributeBufs[i], numPacket, &wg, hashs, i)//"block1.json"这样参数不需要
    }
    wg.Wait()

    //第二轮通讯:插入元数据hashs
    command2:= rabbitmq.WriteHashCommand{
        BucketName: bucketName,
        ObjectName: objectName,
        Hashs: hashs,
        UserId: userId,
    }
    c1,_=json.Marshal(command2)
    b1=append([]byte("04"),c1...)
    rabbit1.PublishSimple(b1)

    //接受第二轮通讯结果
    var res2 rabbitmq.WriteHashRes
    msgs=rabbit2.ConsumeSimple(time.Millisecond, true)
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res2)
            if(res2.MetaCode==0){
                wg.Done()
            }
        }
    }()
    wg.Wait()
    rabbit1.Destroy()
    rabbit2.Destroy()
    //
}

func ecRead(fileSizeInBytes int64, ips []string, blockHashs []string, blockIds []int, ecName string, localFilePath string){
    //根据ecName获得以下参数
    wg := sync.WaitGroup{}
    const ecK int = 2
    const ecN int = 3
    var coefs = [][]int64 {{1,1,1},{1,2,3}}//2应替换为ecK，3应替换为ecN
    
    numPacket := (fileSizeInBytes+int64(ecK)*packetSizeInBytes-1)/(int64(ecK)*packetSizeInBytes)
    fmt.Println(numPacket)
    //创建channel
    var getBufs [ecK]chan []byte
    var decodeBufs [ecK]chan []byte
    for i := 0; i < ecK; i++ {
        getBufs[i] = make(chan []byte)
    }
    for i := 0; i < ecK; i++ {
        decodeBufs[i] = make(chan []byte)
    }
    
    wg.Add(1)
    go get(blockHashs[0], ips[0], getBufs[0], numPacket)
    go get(blockHashs[1], ips[1], getBufs[1], numPacket)
    go encode(getBufs[:], decodeBufs[:], coefs, numPacket)
    go persist(decodeBufs[:], numPacket, localFilePath, &wg)
    wg.Wait()
    
}

func EcWrite(localFilePath string, bucketName string, objectName string, ecName string){
    fmt.Println("write "+localFilePath+" as "+bucketName+"/"+objectName)
    //获取文件大小
    fileInfo,_ := os.Stat(localFilePath)
    fileSizeInBytes := fileInfo.Size()
    fmt.Println(fileSizeInBytes)
    //调用纠删码库，获取编码参数及生成矩阵
    const ecK int = 2
    const ecN int = 3
    var coefs = [][]int64 {{1,1,1},{1,2,3}}//2应替换为ecK，3应替换为ecN

    //计算每个块的packet数
    numPacket := (fileSizeInBytes+int64(ecK)*packetSizeInBytes-1)/(int64(ecK)*packetSizeInBytes)
    fmt.Println(numPacket)
    
    //发送写请求，分配写入节点
    userId :=0
    //发送写请求，分配写入节点Ip 
    command1:= rabbitmq.EcWriteCommand{
        BucketName: bucketName,
        ObjectName: objectName,
        FileSizeInBytes: fileSizeInBytes,
        EcName: ecName,
        UserId: userId,
    }//
    c1,_:=json.Marshal(command1)
    b1:=append([]byte("00"),c1...)//
    fmt.Println(b1)
    rabbit1 := rabbitmq.NewRabbitMQSimple("coorQueue")
    rabbit1.PublishSimple(b1)

    //接收消息，赋值给ips
    var res1 rabbitmq.WriteRes
    var ips []string
    queueName := "coorClientQueue"+strconv.Itoa(userId)
    rabbit2 := rabbitmq.NewRabbitMQSimple(queueName)
    msgs:=rabbit2.ConsumeSimple(time.Millisecond, true)
    wg := sync.WaitGroup{}
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res1)
            ips=res1.Ips
            wg.Done()
        }
    }()
    wg.Wait()   

    //创建channel
    var loadBufs [ecK]chan []byte
    var encodeBufs [ecN]chan []byte

    for i := 0; i < ecK; i++ {
        loadBufs[i] = make(chan []byte)
    }
    
    for i := 0; i < ecN; i++ {
        encodeBufs[i] = make(chan []byte)
    }

    //正式开始写入
    go load(localFilePath, loadBufs[:], numPacket*int64(ecK), fileSizeInBytes)//从本地文件系统加载数据
    go encode(loadBufs[:], encodeBufs[:], coefs, numPacket)
    wg.Add(3)
    hashs:= make([]string, 3)
    go send("block1.json", ips[0], encodeBufs[0], numPacket, &wg, hashs, 0)//"block1.json"这样参数不需要
    go send("block2.json", ips[1], encodeBufs[1], numPacket, &wg, hashs, 1)
    go send("block3.json", ips[2], encodeBufs[2], numPacket, &wg, hashs, 2)
    wg.Wait()

    //第二轮通讯:插入元数据hashs
    command2:= rabbitmq.WriteHashCommand{
        BucketName: bucketName,
        ObjectName: objectName,
        Hashs: hashs,
        UserId: userId,
    }
    c1,_=json.Marshal(command2)
    b1=append([]byte("01"),c1...)
    rabbit1.PublishSimple(b1)

    //接受第二轮通讯结果
    var res2 rabbitmq.WriteHashRes
    msgs=rabbit2.ConsumeSimple(time.Millisecond, true)
    wg.Add(1)
    go func() {
        for d := range msgs {
            _ = json.Unmarshal(d.Body, &res2)
            if(res2.MetaCode==0){
                wg.Done()
            }
        }
    }()
    wg.Wait()
    rabbit1.Destroy()
    rabbit2.Destroy()
    //
}

func repMove(ip string, hash string){
    //通过消息队列发送调度命令
}

func ecMove(ip string, hashs []string, ids []int, ecName string){
    //通过消息队列发送调度命令
}

func loadDistribute(localFilePath string, loadDistributeBufs []chan []byte, numWholePacket int64, lastPacketInBytes int64){
    fmt.Println("loadDistribute "+ localFilePath)
    file, _ := os.Open(localFilePath)
    for i:=0;int64(i)<numWholePacket;i++ {
        buf := make([]byte, packetSizeInBytes)
        _, err := file.Read(buf)
        if err != nil && err != io.EOF {
            break
        }
        for j:=0;j<len(loadDistributeBufs);j++ {
            loadDistributeBufs[j]<-buf
        }
    }
    if lastPacketInBytes>0 {
        buf := make([]byte, lastPacketInBytes)
        file.Read(buf)
        for j:=0;j<len(loadDistributeBufs);j++ {
            loadDistributeBufs[j]<-buf
        }
    }
    fmt.Println("load over")
    for i:=0;i<len(loadDistributeBufs);i++{
        close(loadDistributeBufs[i])
    }
    file.Close()
}

func load(localFilePath string, loadBufs []chan []byte, totalNumPacket int64, fileSizeInBytes int64){
    fmt.Println("load "+ localFilePath)
    file, _ := os.Open(localFilePath)
    for i:=0;int64(i)<totalNumPacket;i++ {
        buf := make([]byte, packetSizeInBytes)
        _, err := file.Read(buf)
        if err != nil && err != io.EOF {
            break
        }
        idx:=i%len(loadBufs)
        loadBufs[idx]<-buf
    }
    fmt.Println("load over")
    for i:=0;i<len(loadBufs);i++{
        close(loadBufs[i])
    }
    file.Close()
}

func encode(inBufs []chan []byte, outBufs []chan []byte, coefs [][]int64, numPacket int64){
    fmt.Println("encode ")
    var tmpIn [][]byte
    tmpIn = make([][]byte, len(inBufs))
    
    for i := 0; int64(i) < numPacket; i++ {
        for j :=0; j < len(inBufs); j++ {//2
            tmpIn[j]=<-inBufs[j]
            //fmt.Println(tmpIn[j])

        }    
        for j := 0; j < len(outBufs); j++{
            tmp := make([]byte, packetSizeInBytes)
            for k := 0; k < packetSizeInBytes; k++{
                for w := 0; w < len(inBufs); w++{
                    //示意，需要调用纠删码编解码引擎：  tmp[k] = tmp[k]+(tmpIn[w][k]*coefs[w][j])  
                    /*fmt.Println(w)
                    fmt.Println(k)
                    fmt.Println(i)
                    fmt.Println(tmpIn[w])
                    fmt.Println(tmpIn[w][k])
                    fmt.Println("-----")*/
                    tmp[k] = tmp[k]+tmpIn[w][k] 
                }
            }
            outBufs[j]<-tmp
         }
    }
    fmt.Println("encode over")
    for i:=0;i<len(outBufs);i++{
        close(outBufs[i])
    }
}

func send(blockhash string, ip string, inBuf chan []byte, numPacket int64, wg *sync.WaitGroup, hashs []string, idx int){
    fmt.Println("send "+blockhash)
    //rpc相关
    conn, err := grpc.Dial(ip+port, grpc.WithInsecure())
    if err != nil {
        panic(err)
    }
       
    client := agentcaller.NewTranBlockOrReplicaClient(conn)

    stream, err := client.SendBlockOrReplica(context.Background())
    if err != nil {
        panic(err)
    }
    for i:=0;int64(i)<numPacket;i++{
        buf:=<-inBuf
        fmt.Println(buf)
        err:=stream.Send(&agentcaller.BlockOrReplica{
            BlockOrReplicaName: blockhash,
            BlockOrReplicaHash: blockhash,
            BlockOrReplicaData: buf,
        })
        if err != nil && err != io.EOF{
            panic(err)
        }
	}
    res, err := stream.CloseAndRecv()
    fmt.Println(res)
    hashs[idx]=res.BlockOrReplicaHash
    conn.Close()
    wg.Done()
    return
}

func get(blockHash string, ip string, getBuf chan []byte, numPacket int64){
    //rpc相关
    conn, err := grpc.Dial(ip+port, grpc.WithInsecure())
    if err != nil {
        panic(err)
    }
    client := agentcaller.NewTranBlockOrReplicaClient(conn) 
    //rpc get
    stream, _ := client.GetBlockOrReplica(context.Background(), &agentcaller.GetReq{
		BlockOrReplicaHash: blockHash,
	})
    fmt.Println(numPacket)
	for i:=0;int64(i)<numPacket;i++{
        fmt.Println(i)
		res, _:= stream.Recv()
	    fmt.Println(res.BlockOrReplicaData)
        getBuf<-res.BlockOrReplicaData
	}
    close(getBuf)
    conn.Close()
}


func persist(inBuf []chan []byte, numPacket int64, localFilePath string, wg *sync.WaitGroup){
    fDir, err := os.Executable()
    if err != nil {
        panic(err)
    }
    fURL := filepath.Join(filepath.Dir(fDir), "assets")
    _, err = os.Stat(fURL)
    if os.IsNotExist(err) {
        os.MkdirAll(fURL, os.ModePerm)
    }

    file, err := os.Create(filepath.Join(fURL, localFilePath))
    if err != nil {
        return
    }
    
    for i := 0; int64(i) < numPacket; i++ {
        for j := 0; j < len(inBuf); j++{
            tmp:=<-inBuf[j]
            fmt.Println(tmp)
            file.Write(tmp)
        }
    }
    file.Close()
    wg.Done()
}