(.module:
  [library
   [lux "*"
    ["_" test {"+" Test}]
    [abstract
     [equivalence {"+" Equivalence}]
     [hash {"+" Hash}]
     ["[0]" monad {"+" do}]]
    [control
     ["[0]" io]
     ["[0]" try]
     ["[0]" exception {"+" exception:}]]
    [data
     ["[0]" product]
     ["[0]" binary {"+" Binary}]
     ["[0]" text
      ["%" format {"+" format}]]
     [collection
      ["[0]" dictionary {"+" Dictionary}]]]
    [math
     ["[0]" random {"+" Random}]]
    [world
     [net
      ["[0]" uri {"+" URI}]]]]]
  ["[0]" / "_"
   ["[1][0]" identity]
   ["[1][0]" origin]
   ["[1][0]" local]
   ["[1][0]" remote]
   [//
    ["@[0]" artifact]]]
  [\\specification
   ["$[0]" /]]
  [\\program
   ["[0]" /
    ["[0]" remote]
    ["/[1]" // "_"
     ["[1][0]" artifact {"+" Version Artifact}
      ["[1]/[0]" extension {"+" Extension}]]]]])

(def: artifact
  (-> Version Artifact)
  (|>> ["com.github.luxlang" "test-artifact"]))

(exception: (not_found [uri URI])
  (exception.report
   ["URI" (%.text uri)]))

(exception: (cannot_upload [uri URI])
  (exception.report
   ["URI" (%.text uri)]))

(type: Store
  (Dictionary URI Binary))

(def: .public empty
  Store
  (dictionary.empty text.hash))

(def: valid_version
  Version
  "1.2.3-YES")

(def: invalid_version
  Version
  "4.5.6-NO")

(implementation: .public mock
  (/.Mock Store)

  (def: the_description
    "@")
  (def: (on_download uri state)
    (case (dictionary.value uri state)
      {.#Some content}
      (case (binary.size content)
        0 (exception.except ..not_found [uri])
        _ {try.#Success [state content]})
      
      {.#None}
      (exception.except ..not_found [uri])))
  (def: (on_upload uri content state)
    (if (dictionary.key? state uri)
      (exception.except ..cannot_upload [uri])
      {try.#Success (dictionary.has uri content state)})))

(def: .public test
  Test
  (<| (_.covering /._)
      ($_ _.and
          (_.for [/.mock /.Mock]
                 (do random.monad
                   [_ (in [])]
                   ($/.spec (..artifact ..valid_version)
                            (..artifact ..invalid_version)
                            (/.mock ..mock
                                    (|> ..empty
                                        (dictionary.has (remote.uri ..invalid_version
                                                                    (..artifact ..invalid_version)
                                                                    //artifact/extension.lux_library)
                                                        (binary.empty 0)))))))

          /identity.test
          /origin.test
          /local.test
          /remote.test
          )))