kitty-print-png.nim

import std/[cmdline, base64]

proc writePng(f: File; pngdata: string) =
  let bytes = pngdata.encode
  const CHUNK_SIZE = 4096

  var remaining = bytes.len

  var i = 0
  while remaining > 0:
    let (numread, m) =
      if remaining > CHUNK_SIZE:
        (CHUNK_SIZE, "m=1")
      else:
        (remaining, "")
    let encoded = bytes[i..<i+numread]
    
    f.write "\e_G"
    if i == 0:
      f.write "a=T,f=100,"
    f.write m
    f.write ";"
    f.write encoded
    f.write "\e\\"

    remaining -= numread
    i += numread

proc main =
  let filename = paramStr(1)
  stdout.writePng(readFile(filename))

main()