app "main"
    packages { pf: "platform/main.roc" }
    imports [Parser.Core.{Parser}, Parser.Str.{RawStr}, Parser.CSV.{CSV}]
    provides [main] to pf

# Until issue https://github.com/rtfeldman/roc/issues/3438 is fixed,
# use the simple 'hello world' platform for testing
# with hard-coded input.


main = fullTest csvParser "10,20\n\"An escaped field!\"\"\n,,,\",30\n"
# main = partialTest fieldParser "\"An escaped field with some \"\"<- double quotes\""
# main = fullTest fieldContentsParser "My very cool,\"\"\r\n string"
# main = partialTest betweenParser "\"this is a test\"\" to see\""
# main = partialTest manyParser "this is a very long string\"\""

partialTest = \parser, input ->
  when Parser.Str.parseStrPartial parser input is
    Ok result ->
      # val = result.val |> Str.joinWith("\r\n")
      val = result.val
      leftover = result.input
      "Parse success: \(val) (leftover string: \(leftover))\n"
    Err (ParsingFailure problem) ->
      "Parse failure: \(problem)\n"

fullTest = \parser, input ->
  when Parser.Str.parseStr parser input is
    Ok result ->
      # val = result |> Str.joinWith(", ")
      val = result |> Str.joinWith("\r\n")
      # val = result
      "Parse success: \(val)\n"
    Err (ParsingFailure problem) ->
      "Parse failure: \(problem)\n"
    Err (ParsingIncomplete leftover) ->
      "Parse failure: Expected to reach end of input, but the following was still left: `\(leftover)`\n"

betweenParser : Parser RawStr Str
betweenParser =
  Parser.Core.between manyParser (Parser.Str.codepoint 34) (Parser.Str.codepoint 34)

manyParser : Parser RawStr Str
manyParser =
  Parser.Str.string "\"\"" |> Parser.Core.map(\_ -> 34) # Escaped double quote
  |> Parser.Core.alt (Parser.Str.codepoint 44) # Comma
  |> Parser.Core.alt (Parser.Str.codepoint 13) # CR
  |> Parser.Core.alt (Parser.Str.codepoint 10) # LF
  |> Parser.Core.alt (Parser.Str.codepointSatisfies (\x -> (x >= 32 && x <= 33) || (x >= 35 && x <= 43) || (x >= 45 && x <= 126))) # Any printable char except " (34) and , (44)
  |> Parser.Core.many
  |> Parser.Core.map (\field -> field |> Str.fromUtf8 |> Result.withDefault "Should not happen")

fieldContentsParser : Parser RawStr Str
fieldContentsParser =
  Parser.CSV.escapedContents
  |> Parser.Core.map (\field -> field |> Str.fromUtf8 |> Result.withDefault "Should not happen")

fieldParser : Parser RawStr Str
fieldParser =
  Parser.CSV.escapedField
  |> Parser.Core.map (\field -> field |> Str.fromUtf8 |> Result.withDefault "Should not happen")

csvParser : Parser RawStr (List Str)
csvParser =
  Parser.CSV.file
  |> Parser.Core.map \records ->
    records
    |> List.map (\record ->
      record
      |> List.map (\field ->
        field
        |> Str.fromUtf8
        |> Result.withDefault "Unexpected problem while turning a List U8 back into a Str")
      |> Str.joinWith ", ")