local path = require('path')
local w = require('tables').wrap
local parser = clink.arg.new_parser

local NVM_ROOT

local function get_nvm_root()
    if NVM_ROOT then return NVM_ROOT end

    local proc = io.popen("nvm root")
    if not proc then
        NVM_ROOT = ""
        return NVM_ROOT
    end

    local lines = proc:read('*all')
    NVM_ROOT = lines:match("Current Root:%s(.*)%s*\n$") or ""
    proc:close()

    return NVM_ROOT
end

local installed = function ()
    return w(clink.find_dirs(get_nvm_root().."/*"))
    :filter(path.is_real_dir)
    :map(function (dir)
        return dir:match("v(.*)")
    end)
end

local archs = parser({"64", "32"})

local nvm_parser = parser({
    "arch"..archs,
    "install"..parser({"latest"}, archs),
    "list"..parser({installed, "available"}),
    "ls"..parser({installed, "available"}),
    "on", "off",
    "proxy"..parser({"none"}),
    "uninstall"..parser({installed}),
    "use"..parser({installed}, archs),
    "root",
    "version", "v"
}, "-h", "--help", "-v", "--version")

clink.arg.register_parser("nvm", nvm_parser)