module Hadolint.Rule.DL3021 (rule) where

import qualified Data.Text as Text
import Hadolint.Rule
import Language.Docker.Syntax

rule :: Rule args
rule = simpleRule code severity message check
  where
    code = "DL3021"
    severity = DLErrorC
    message = "COPY with more than 2 arguments requires the last argument to end with /"

    check (Copy (CopyArgs sources t _ _ _))
      | length sources > 1 = endsWithSlash t
      | otherwise = True
    check _ = True
{-# INLINEABLE rule #-}

endsWithSlash :: TargetPath -> Bool
endsWithSlash (TargetPath t) =
  not (Text.null t) && (Text.last . dropQuotes) t == '/'