69 lines
1.4 KiB
Go
69 lines
1.4 KiB
Go
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// Package telnet provides some fancy tools, like an ASCII-art stream.
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package telnet
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import (
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"io"
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"log"
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"net"
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"time"
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)
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func asciiChar(pixel byte) string {
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asciiChars := []string{"@", "#", "$", "%", "?", "*", "+", ";", ":", ",", "."}
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return asciiChars[pixel/25]
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}
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// ServeAsciiArt starts a telnet server that send all packets as ASCII Art
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func ServeAsciiArt(reader io.Reader) {
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listener, err := net.Listen("tcp", ":4242")
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if err != nil {
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log.Printf("Error while listening to the port 4242: %s", err)
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return
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}
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currentMessage := ""
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go func() {
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for {
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s, err := listener.Accept()
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if err != nil {
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log.Printf("Error while accepting TCP socket: %s", s)
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continue
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}
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go func(s net.Conn) {
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for {
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n, err := s.Write([]byte(currentMessage))
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if err != nil {
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log.Printf("Error while sending TCP data: %s", err)
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_ = s.Close()
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break
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}
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if n == 0 {
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_ = s.Close()
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break
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}
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time.Sleep(50 * time.Millisecond)
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}
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}(s)
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}
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}()
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buff := make([]byte, 2048)
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header := "\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n"
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for {
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n, _ := reader.Read(buff)
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if n == 0 {
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break
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}
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imageStr := ""
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for j := 0; j < 18; j++ {
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for i := 0; i < 32; i++ {
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pixel := buff[32*j+i]
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imageStr += asciiChar(pixel) + asciiChar(pixel)
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}
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imageStr += "\n"
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}
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currentMessage = header + imageStr
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}
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}
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