arch

local tEncode = {
  string = "a",
  table = "b",
  ["local"] = "c",
  ["function"] = "d",
  textutils = "e",
  paintutils = "f",
  ["while"] = "g",
  ["repeat"] = "h",
  ["until"] = "i",
  print = "j",
  ["return"] = "k",
  shell = "l",
  ["else"] = "m",
  ["end"] = "n",
  colour = "o",
  color = "o",
  setCursorPos = "p",
  setTextColour = "q",
  setTextColor = "q",
  setBackgroundColour = "r",
  setBackgroundColor = "r",
  number = "s",
  sleep = "t",
  rednet = "u",
  ["true"] = "v",
  ["false"] = "w",
  pairs = "x",
  math = "y",
  term = "z",
  pullEvent = "-"
}

local tDecode = {}
for k, v in pairs(tEncode) do
  tDecode[v] = k
end

tArgs = {...}

local function printUsage()
  local pr = shell.getRunningProgram()
  print("Usage: "..pr.." flags path ...\nFlags:\n c Create archive\n x Extract archive\n v Verbose\n f For creating archive specify output filename\n   (default: archive.ar)\nExample:\n"..pr.." cvf sample.ar main.lua libs\n"..pr.." xv sample.ar")
end

local function splitName(sPath)
  local sPath = fs.getName(sPath)
  if not sPath:sub(2):find("%.") then return sPath, "" end
  local nDelim = sPath:find("%.")
  return sPath:sub(1, nDelim-1), sPath:sub(nDelim+1)
end

local function trySave(sPath, sData)
  if fs.exists(sPath) then
    local sF, sE = splitName(sPath)
    local sNewPath = sF.."-copy."..sE
    print(sPath..": File already exists.\n1) Skip\n2) Overwrite\n3) Save as "..sNewPath)
    while true do
      write("> ")
      local nOption = tonumber(read())
      if nOption==1 then
        return false
      elseif nOption==2 then
        local fHandle = fs.open(sPath, "w")
        fHandle.write(sData)
        fHandle.close()
        return true
      elseif nOption==3 then
        return trySave(sNewPath, sData)
      end
    end
  else
    local fHandle = fs.open(sPath, "w")
    fHandle.write(sData)
    fHandle.close()
    return true
  end
end

local function parse(sFile)
  local sPath = shell.resolve(sFile)
  if fs.isDir(sPath) then
    local sOut1, sOut2 = "", ""

    local tFiles = fs.list(sPath)
    print(tFiles)
    for i=1, #tFiles do
      local s1, s2 = parse(sFile.."/"..tFiles[i])
      sOut1 = sOut1..s1
      sOut2 = sOut2..s2
    end

    return sOut1, sOut2
  else
    local fHandle = fs.open(sPath, "r")
    local sContent = fHandle.readAll()
    fHandle.close()
    sContent = sContent:gsub("\\", "\\|")
    for k, v in pairs(tEncode) do
      sContent = sContent:gsub(k, "\\"..v)
    end
    return sFile.."\\/", sContent.."\\/"
  end
end

if #tArgs<2 then
  printUsage()
  return
end

local sFlags = tArgs[1]
local tFiles = {}
for i=2, #tArgs do tFiles[i-1] = tArgs[i] end

local bEncoding = sFlags:find("c")~=nil
local bDecoding = sFlags:find("x")~=nil
local bVerbose = sFlags:find("v")~=nil
local bOutputFile = sFlags:find("f")~=nil
local sOutputFile = "archive.ar"

if bOutputFile and bEncoding then
  if #tFiles<2 then
    printUsage()
    return
  end
  sOutputFile = shell.resolve(tFiles[1])
  table.remove(tFiles, 1)
end

if bEncoding==bDecoding then
  printUsage()
  return
end

if bDecoding then

  for i=1, #tFiles do
    local sFile = shell.resolve(tFiles[i])
    if not fs.exists(sFile) then
      print(sFile..": No such file or directory")
    elseif fs.isDir(sFile) then
      print(sFile..": Is a directory")
    else
      local fHandle = fs.open(sFile, "r")
      local sData = fHandle.readAll()
      fHandle.close()
      if sData:sub(1,2)~="AR" then
        print(sFile..": Is not an archive")
      else

        sData = sData:sub(3)
        local tFilenames = {}
        repeat
          local nDelim = sData:find("\\[\\/]")
          local sDelim = sData:sub(nDelim,nDelim+1)
          table.insert(tFilenames, shell.resolve(sData:sub(1, nDelim-1)))
          sData = sData:sub(nDelim+2)
        until sDelim=="\\\\"

        for i=1, #tFilenames do
          local nDelim = sData:find("\\\/")
          if nDelim==nil then
            print(sFile..": Malformed data")
            return
          end
          local sContent = sData:sub(1, nDelim-1)
          for k, v in pairs(tDecode) do
            sContent = sContent:gsub("\\"..k, v)
          end
          sContent = sContent:gsub("\\|", "\\")
          trySave(tFilenames[i], sContent)
          sData = sData:sub(nDelim+2)
        end

      end
    end
  end

elseif bEncoding then

  local sOutput1 = "AR"
  local sOutput2 = ""

  for i=1, #tFiles do
    local sFile = shell.resolve(tFiles[i])
    if not fs.exists(sFile) then
      print(sFile..": No such file or directory")
    else
      local s1, s2 = parse(tFiles[i])
      sOutput1 = sOutput1..s1
      sOutput2 = sOutput2..s2
    end
  end

  sOutput1 = sOutput1:sub(1, #sOutput1-2)

  local sOutput = sOutput1.."\\\\"..sOutput2
  trySave(sOutputFile, sOutput)

end