telegram echo bot

AddonInfo <- {
  "Name":"Telegram bot"
  "Summary":"Telegram bot API"
  "Version":"0.01"
  "Author":"NovaSquirrel"
};

// Calls a Telegram API function and calls a callback
function DoAPI(Method, Parameters, Function, Extra) {
  function DoNothing(C, D, E){};
  const Key = "insert key here";
  local URL = "https://api.telegram.org/bot"+Key+"/"+Method;
  if(Function == null)
    Function = DoNothing;
  if(Parameters)
    api.CurlPost(Function, Extra, URL, api.MakeForms(Parameters));
  else
    api.CurlGet(Function, Extra, URL);
}

// Telegram sends chat IDs as big integers, but Squirrel by default only has 32-bit ones
// so change the integers to the strings they should have been in the first place
function ChatIDFix(Text) {
  function isdigit(character) {
    return character >= '0' && character <= '9';
  }

  local FindMe = @"""chat"":{""id"":";
  local FixedText = "";
  local CurIndex = 0;

  while(1) {
    local FindIndex = Text.find(FindMe, CurIndex);
    if(FindIndex == null) {
      FixedText += Text.slice(CurIndex);
      break;
    }
    // add the text up until the found thing
    FixedText += Text.slice(CurIndex, FindIndex)+FindMe+"\"";
    CurIndex = FindIndex+FindMe.len();
    // add the number, and close off the quotation mark
    while(isdigit(Text[CurIndex]))
      FixedText += format("%c", Text[CurIndex++]);
    FixedText += "\"";
  }

  return FixedText;
}

local UpdateId = 0;

function ApiTestCmd(T, P, C) {
  P = api.CmdParamSplit(P);

  function RequestUpdates() {
    if(UpdateId)
      DoAPI("getUpdates", {"offset":UpdateId+1, "timeout":60}, GotAnswer, null);
    else
      DoAPI("getUpdates", {"timeout":60}, GotAnswer, null);
  }

  // Got an update
  function GotUpdate(Code, Data, Extra) {
    Data = api.DecodeJSON(ChatIDFix(Data));

    foreach(Update in Data.result) {
      if(Update.update_id > UpdateId)
        UpdateId = Update.update_id;
      local Message = Update.message;
      local From = ("from" in Message)?Message.from.username:"?";
      local Text = ("text" in Message)?Message.text:null;
      if(Text) {
        print(From+":"+Text);
        DoAPI("sendMessage", {"chat_id":Message.chat.id, "text":Text}, null, null);
      }
    }
    RequestUpdates();
  }
  RequestUpdates();
  return EventReturn.HANDLED;
}
api.AddCommandHook("tgtest",  ApiTestCmd, Priority.NORMAL, null, null);