settings.define("auth.token", {
    description = "Authentication token",
    type = "number",
    default = -1
})

settings.define("auth.server", {
    description = "Authentication server",
    type = "string",
    default = "auth.box"
})


function get_token()
    return settings.get("auth.token")
end

function check_user_group(username, group)
    local data = {
        ["action"] = "check_group",
        ["username"] = username,
        ["group"] = group
    }

    local auth_server_id = lns.lookup(settings.get("auth.server"))
    rednet.send(auth_server_id, data, "auth")

    while true do
        id, msg = rednet.receive("auth")
        if id == auth_server_id then
            if msg == "invalid request" then
                io.write("Invalid request\n")
                return
            elseif msg == "user not found" then
                io.write("User not found\n")
                return
            elseif msg == "invalid token" then
                io.write("Invalid token\n")
                return
            elseif msg == "invalid group" then
                io.write("Invalid group\n")
                return
            elseif msg == "ok" then
                return true
            else
                return false
            end
        end
    end
end


function list_to_string(list)
    local str = ""
    for i, v in ipairs(list) do
        str = str .. v .. ", "
    end
    return str:sub(1, -3)
end

function list_user_groups(username)
    local data = {
        ["action"] = "list_groups",
        ["username"] = username
    }

    local auth_server_id = lns.lookup(settings.get("auth.server"))
    rednet.send(auth_server_id, data, "auth")

    while true do
        id, msg = rednet.receive("auth")
        if id == auth_server_id then
            if msg == "invalid request" then
                io.write("Invalid request\n")
                return
            elseif msg == "user not found" then
                io.write("User not found\n")
                return
            elseif msg == "invalid token" then
                io.write("Invalid token\n")
                return
            else
                return msg
            end
        end
    end
end

function add_user_to_group(username, group)
    local data = {
        ["action"] = "add_group",
        ["username"] = username,
        ["group"] = group,
        ["token"] = get_token()
    }

    local auth_server_id = lns.lookup(settings.get("auth.server"))
    rednet.send(auth_server_id, data, "auth")

    while true do
        id, msg = rednet.receive("auth")
        if id == auth_server_id then
            if msg == "invalid request" then
                io.write("Invalid request\n")
                return false
            elseif msg == "user not found" then
                io.write("User not found\n")
                return false
            elseif msg == "invalid token" then
                io.write("Invalid token\n")
                return false
            elseif msg == "invalid privileges" then
                io.write("Invalid privileges\n")
                return false
            elseif msg == "ok" then
                return true
            else
                return false
            end
        end
    end
end