use regex::Regex;

#[allow(dead_code)]
pub fn rkey_to_url(rkey: String) -> Option<String> {
  let regex = Regex::new(
    // symbols A-Za-z0-9 -._~: are all valid rkey characters
    // however we use a subset of record keys where : is an escape character
    // allow any rkey character except colons
    // or any of the valid escape sequences
    // from start of string to end between 0 and unlimited times
    r"^(?:[A-Za-z0-9.\-_~]|(?:::)|(?::~)|(?::21)|(?::24)|(?::26)|(?::27)|(?::28)|(?::29)|(?::2A)|(?::2B)|(?::2C)|(?::3A)|(?::3B)|(?::3D)|(?::40))*$",
  )
  .expect("Regex failed to generate");

  if !regex.is_match(&rkey) {
    return None;
  };

  let res = rkey
    .replace("::", "/")
    .replace(":~", "%")
    .replace(":21", "!")
    .replace(":24", "$")
    .replace(":26", "&")
    .replace(":27", "'")
    .replace(":28", "(")
    .replace(":29", ")")
    .replace(":2A", "*")
    .replace(":2B", "+")
    .replace(":2C", ",")
    .replace(":3A", ":")
    .replace(":3B", ";")
    .replace(":3D", "=")
    .replace(":40", "@");

  Some(res)
}

pub fn url_to_rkey(url: String) -> Option<String> {
  let regex = Regex::new(r"^(?:[a-zA-Z0-9/\-._~!$&'()*+,;=:@]|(?:%[0-9a-fA-F]{2}))*$")
    .expect("Regex failed to generate");
  if !regex.is_match(&url) {
    return None;
  }

  let res = url
    // : replace is hoisted so it doesnt replace colons from elsewhere
    .replace(":", ":3A")
    .replace("/", "::")
    .replace("%", ":~")
    .replace("!", ":21")
    .replace("$", ":24")
    .replace("&", ":26")
    .replace("'", ":27")
    .replace("(", ":28")
    .replace(")", ":29")
    .replace("*", ":2A")
    .replace("+", ":2B")
    .replace(",", ":2C")
    .replace(";", ":3B")
    .replace("=", ":3D")
    .replace("@", ":40");

  Some(res)
}

pub fn site_handle(user: String) -> String {
  if user.contains(":") {
    let user = user.split(":").collect::<Vec<_>>();
    let method = user[1];
    let did = user[2];
    format!("https://{did}.did-{method}.atcities.dev/")
  } else {
    format!("https://{user}.atcities.dev/")
  }
}