// SPDX-FileCopyrightText: Gordon Leung <pirateclip@protonmail.com>
// SPDX-License-Identifier: MPL-2.0
import gleam/string
import internal/regexing

/// Glingify your strings
pub fn glingify_en(str: String) -> String {
  regexing.glingify_by_regex(str, "([a-zA-Z]*)([^a-zA-Z]*)", glingify_word_en)
}

/// Glingify a single word
pub fn glingify_word_en(word: String) -> String {
  case string.pop_grapheme(word) {
    Ok(#("e", _))
    | Ok(#("a", _))
    | Ok(#("i", _))
    | Ok(#("o", _))
    | Ok(#("u", _)) -> string.append("gl", word)

    Ok(#("r", rest))
    | Ok(#("h", rest))
    | Ok(#("j", rest))
    | Ok(#("l", rest))
    | Ok(#("m", rest))
    | Ok(#("n", rest))
    | Ok(#("v", rest))
    | Ok(#("x", rest))
    | Ok(#("y", rest))
    | Ok(#("z", rest)) -> string.append("gl", rest)

    Ok(#("b", rest)) | Ok(#("d", rest)) | Ok(#("f", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("r", tail)) -> string.append("gl", tail)
        Ok(#(_, _)) -> string.append("gl", rest)
        Error(_) -> "gl"
      }

    Ok(#("c", rest))
    | Ok(#("g", rest))
    | Ok(#("k", rest))
    | Ok(#("p", rest))
    | Ok(#("q", rest))
    | Ok(#("t", rest))
    | Ok(#("w", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("h", tail)) | Ok(#("r", tail)) | Ok(#("l", tail)) ->
          string.append("gl", tail)
        Ok(#(_, _)) -> string.append("gl", rest)
        Error(_) -> "gl"
      }

    Ok(#("s", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("t", tail)) | Ok(#("h", tail)) -> string.append("gl", tail)
        Ok(#(_, _)) -> string.append("gl", rest)
        Error(_) -> "gl"
      }

    Ok(#("E", rest))
    | Ok(#("A", rest))
    | Ok(#("I", rest))
    | Ok(#("O", rest))
    | Ok(#("U", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("A", _))
        | Ok(#("B", _))
        | Ok(#("C", _))
        | Ok(#("D", _))
        | Ok(#("E", _))
        | Ok(#("F", _))
        | Ok(#("G", _))
        | Ok(#("H", _))
        | Ok(#("I", _))
        | Ok(#("J", _))
        | Ok(#("K", _))
        | Ok(#("L", _))
        | Ok(#("M", _))
        | Ok(#("N", _))
        | Ok(#("O", _))
        | Ok(#("P", _))
        | Ok(#("Q", _))
        | Ok(#("R", _))
        | Ok(#("S", _))
        | Ok(#("T", _))
        | Ok(#("U", _))
        | Ok(#("V", _))
        | Ok(#("W", _))
        | Ok(#("X", _))
        | Ok(#("Y", _))
        | Ok(#("Z", _)) -> string.append("GL", word)
        Ok(#(_, _)) -> string.append("Gl", word)
        Error(_) -> "Gl"
      }

    Ok(#("R", rest))
    | Ok(#("H", rest))
    | Ok(#("J", rest))
    | Ok(#("L", rest))
    | Ok(#("M", rest))
    | Ok(#("N", rest))
    | Ok(#("V", rest))
    | Ok(#("X", rest))
    | Ok(#("Y", rest))
    | Ok(#("Z", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("A", _))
        | Ok(#("B", _))
        | Ok(#("C", _))
        | Ok(#("D", _))
        | Ok(#("E", _))
        | Ok(#("F", _))
        | Ok(#("G", _))
        | Ok(#("H", _))
        | Ok(#("I", _))
        | Ok(#("J", _))
        | Ok(#("K", _))
        | Ok(#("L", _))
        | Ok(#("M", _))
        | Ok(#("N", _))
        | Ok(#("O", _))
        | Ok(#("P", _))
        | Ok(#("Q", _))
        | Ok(#("R", _))
        | Ok(#("S", _))
        | Ok(#("T", _))
        | Ok(#("U", _))
        | Ok(#("V", _))
        | Ok(#("W", _))
        | Ok(#("X", _))
        | Ok(#("Y", _))
        | Ok(#("Z", _)) -> string.append("GL", rest)
        Ok(#(_, _)) -> string.append("Gl", rest)
        Error(_) -> "Gl"
      }

    Ok(#("B", rest)) | Ok(#("D", rest)) | Ok(#("F", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("r", tail)) -> string.append("Gl", tail)
        Ok(#("A", _))
        | Ok(#("B", _))
        | Ok(#("C", _))
        | Ok(#("D", _))
        | Ok(#("E", _))
        | Ok(#("F", _))
        | Ok(#("G", _))
        | Ok(#("H", _))
        | Ok(#("I", _))
        | Ok(#("J", _))
        | Ok(#("K", _))
        | Ok(#("L", _))
        | Ok(#("M", _))
        | Ok(#("N", _))
        | Ok(#("O", _))
        | Ok(#("P", _))
        | Ok(#("Q", _))
        | Ok(#("S", _))
        | Ok(#("T", _))
        | Ok(#("U", _))
        | Ok(#("V", _))
        | Ok(#("W", _))
        | Ok(#("X", _))
        | Ok(#("Y", _))
        | Ok(#("Z", _)) -> string.append("GL", rest)
        Ok(#("R", tail)) -> string.append("GL", tail)
        Ok(#(_, _)) -> string.append("Gl", rest)
        Error(_) -> "Gl"
      }
    Ok(#("C", rest))
    | Ok(#("G", rest))
    | Ok(#("K", rest))
    | Ok(#("P", rest))
    | Ok(#("Q", rest))
    | Ok(#("T", rest))
    | Ok(#("W", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("h", tail)) | Ok(#("r", tail)) | Ok(#("r", tail)) ->
          string.append("Gl", tail)
        Ok(#("A", _))
        | Ok(#("B", _))
        | Ok(#("C", _))
        | Ok(#("D", _))
        | Ok(#("E", _))
        | Ok(#("F", _))
        | Ok(#("G", _))
        | Ok(#("I", _))
        | Ok(#("J", _))
        | Ok(#("K", _))
        | Ok(#("M", _))
        | Ok(#("N", _))
        | Ok(#("O", _))
        | Ok(#("P", _))
        | Ok(#("Q", _))
        | Ok(#("S", _))
        | Ok(#("T", _))
        | Ok(#("U", _))
        | Ok(#("V", _))
        | Ok(#("W", _))
        | Ok(#("X", _))
        | Ok(#("Y", _))
        | Ok(#("Z", _)) -> string.append("GL", rest)
        Ok(#("H", tail)) | Ok(#("R", tail)) | Ok(#("L", tail)) ->
          string.append("GL", tail)
        Ok(#(_, _)) -> string.append("Gl", rest)
        Error(_) -> "Gl"
      }
    Ok(#("S", rest)) ->
      case string.pop_grapheme(rest) {
        Ok(#("t", tail)) | Ok(#("h", tail)) -> string.append("Gl", tail)
        Ok(#("A", _))
        | Ok(#("B", _))
        | Ok(#("C", _))
        | Ok(#("D", _))
        | Ok(#("E", _))
        | Ok(#("F", _))
        | Ok(#("G", _))
        | Ok(#("I", _))
        | Ok(#("J", _))
        | Ok(#("K", _))
        | Ok(#("L", _))
        | Ok(#("M", _))
        | Ok(#("N", _))
        | Ok(#("O", _))
        | Ok(#("P", _))
        | Ok(#("Q", _))
        | Ok(#("R", _))
        | Ok(#("S", _))
        | Ok(#("U", _))
        | Ok(#("V", _))
        | Ok(#("W", _))
        | Ok(#("X", _))
        | Ok(#("Y", _))
        | Ok(#("Z", _)) -> string.append("GL", rest)
        Ok(#("T", tail)) | Ok(#("H", tail)) -> string.append("GL", tail)
        Ok(#(_, _)) -> string.append("Gl", rest)
        Error(_) -> "Gl"
      }
    Ok(_) -> word
    Error(_) -> ""
  }
}