package util

import (
	"context"
	"errors"

	"basic.com/valib/deliver.git"

	"basic.com/valib/logger.git"
)

const (
	// 共享内存发送/接收失败shmMaxTryCount次重新创建通道尝试
	ShmMaxTryCount = 7
	// 不论共享内存/mangos发送/接收失败最大次数,认为当前通道不再使用, 关闭
	// 有问题,摄像机长时间断网后重连,但是通道关闭
	tooLongFailed = 300

	File_Img_Id_Pre   = "img_"
	File_Video_Id_Pre = "video_"
	File_Audio_Id_Pre = "audio_"
)

type SocketContext struct {
	Sock    deliver.Deliver
	Context context.Context
	Cancel  context.CancelFunc

	Mode   int
	URL    string
	UseSHM bool
}

//  1. oldstring element is not in new  : abandon(delete)
//  2. new element is not in oldstring  : add(add)
func Difference(oldstring []string, newstring []string) map[string]string {
	var diff = make(map[string]string)

	// Loop two times, first to find oldstring strings not in newstring,
	// second loop to find newstring strings not in oldstring
	for i := 0; i < 2; i++ {
		for _, s1 := range oldstring {
			found := false
			for _, s2 := range newstring {
				if s1 == s2 {
					found = true
					break
				}
			}
			// String not found. We add it to return slice
			if !found && i == 0 {
				diff[s1] = "delete"
			}
			if !found && i != 0 {
				diff[s1] = "add"
			}
		}
		// Swap the slices, only if it was the first loop
		if i == 0 {
			oldstring, newstring = newstring, oldstring
		}
	}
	return diff
}

// UnCompress uncompress
func UnCompress(in []byte) ([]byte, error) {
	return in, nil

	// out := make([]byte, 3*len(in))
	// n, err := lz4.UncompressBlock(in, out)
	// if err != nil {
	// 	logger.Error("uncompress error: ", err)
	// 	return nil, err
	// }
	// out = out[:n] // uncompressed data
	// return out, nil
}

// Compress compress
func Compress(in []byte) ([]byte, error) {
	return in, nil

	// out := make([]byte, len(in))
	// ht := make([]int, 64<<10) // buffer for the compression table
	// n, err := lz4.CompressBlock(in, out, ht)
	// if err != nil {
	// 	logger.Error("compress: ", err)
	// 	return nil, err
	// }
	// if n >= len(in) {
	// 	logger.Error("image is not compressible")
	// }
	// out = out[:n] // compressed data
	// return out, nil
}

// create server
func NewSocketListen(mode int, url string, shm bool) (socket SocketContext, err error) {
	ctx, cancel := context.WithCancel(context.Background())

	socket.Context = ctx
	socket.Cancel = cancel

	socket.Mode = mode
	socket.URL = url
	socket.UseSHM = shm

	if shm {
		var err error
		socket.Sock, err = deliver.NewServerWithError(deliver.Mode(mode), url)
		if err != nil {
			logger.Info("TASK CREATE SERVER SHM ERROR: ", err)
		}
	} else {
		socket.Sock = deliver.NewServer(deliver.Mode(mode), url)
	}

	if socket.Sock == nil {
		return socket, errors.New("create listen error")
	}

	return socket, nil
}

func NewSocketDial(mode int, url string) (socket SocketContext, err error) {
	logger.Info("url is: ", url)
	ctx, cancel := context.WithCancel(context.Background())

	socket.Context = ctx
	socket.Cancel = cancel

	socket.Sock = deliver.NewClient(deliver.Mode(mode), url)

	if socket.Sock == nil {
		return socket, errors.New("create listen error")
	}

	return socket, nil
}

func MaybeRestartSocket(socket SocketContext, tryCnt *int) SocketContext {
	if socket.UseSHM {
		if *tryCnt > ShmMaxTryCount {
			logger.Info("SDK SEND SHM TRY :", ShmMaxTryCount, " RESTART IT")

			socket.Sock.Close()
			newSocket, err := NewSocketListen(socket.Mode, socket.URL, socket.UseSHM)
			if err != nil {
				return socket
			}

			*tryCnt = 0

			return newSocket
		}
	}

	return socket
}