client.lua

args = {...}
op = args[1]
server_id = tonumber(args[2])

function split(inputstr, sep)
    if sep == nil then
        sep = "%s"
    end
    local t={}
    for str in string.gmatch(inputstr, "([^"..sep.."]+)") do
        table.insert(t, str)
    end
    return t
end

function tablelength(T)
    local count = 0
    for _ in pairs(T) do count = count + 1 end
    return count
end

if op == "send" or op == "get" then
    file = args[3]
end

local present = false
for _, side in pairs(rs.getSides()) do
    if peripheral.getType(side) == "modem" then
        present = true
        rednet.open(side)
    end
end

if op == "list" then
    rednet.send(server_id, "list:all", "FTP")
    id, list = rednet.receive("FTP")
    files = split(list, ":")
    for i=1,tablelength(files) do
        print(files[i])
    end
elseif op == "get" then
    rednet.send(server_id, "get:" .. file, "FTP")
    id, file_data = rednet.receive("FTP")
    if file_data == "1" then
        printError("file does not exsist on server")
        return
    end
    file_table = split(file_data, ":*:")
    file_name = file_table[1]
    file_content = file_table[2]
    if fs.exists(file_name) == true then
        print("file alredy exsists")
    else
        file = fs.open(file_name, "w")
        file.write(file_content)
        file.close()
    end
    elseif op == "send" then
        print("wip")

end