package connshark

import "os"
import "io"
import "fmt"
import "net"
import "log"
import "sync"
import "math/rand"
import tu "git.tebibyte.media/sashakoshka/hopp/internal/testutil"

type insert struct {
	net.Conn
	output io.WriteCloser
	lock sync.Mutex
}

func LogDebugFile(underlying net.Conn) net.Conn {
	file, err := os.Create(fmt.Sprintf("connshark-%08X.log", rand.Uint32()))
	if err != nil {
		log.Println("XXX COULD NOT OPEN DEBUG FILE! reason: ", err)
		return underlying
	}
	return Log(underlying, file)
}

func Log(underlying net.Conn, output io.WriteCloser) net.Conn {
	return &insert {
		Conn:   underlying,
		output: output,
	}
}

func (this *insert) Read(buffer []byte) (n int, err error) {
	if n > 0 {
		this.lock.Lock()
		defer this.lock.Unlock()
		fmt.Fprintf(this.output, "TX: %s\n", tu.HexBytes(buffer[:n]))
	}
	return n, err
}

func (this *insert) Write(buffer []byte) (n int, err error) {
	n, err = this.Conn.Write(buffer)
	if n > 0 {
		this.lock.Lock()
		defer this.lock.Unlock()
		fmt.Fprintf(this.output, "RX: %s\n", tu.HexBytes(buffer[:n]))
	}
	return n, err
}

func (this *insert) Close() error {
	this.output.Close()
	return this.Conn.Close()
}