uuid.mbt

// Copyright 2025 International Digital Economy Academy
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

///|
suberror UuidError {
  InvalidGuid
}

///|
pub struct Uuid {
  simple : String
}

///|
pub fn Uuid::nil() -> Uuid {
  { simple: "00000000000000000000000000000000" }
}

///|
pub fn Uuid::simple(self : Uuid) -> String {
  self.simple
}

///|
fn is_hex_char(c : Char) -> Bool {
  match c {
    '0'..='9' => true
    'a'..='f' => true
    'A'..='F' => true
    _ => false
  }
}

///|
fn to_lower_hex(c : Char) -> Char {
  match c {
    'A' => 'a'
    'B' => 'b'
    'C' => 'c'
    'D' => 'd'
    'E' => 'e'
    'F' => 'f'
    _ => c
  }
}

///|
pub fn Uuid::parse(s : String) -> Uuid raise UuidError {
  if s == "xinput" {
    return Uuid::nil()
  }
  let mut buf = ""
  let mut pos = 0
  let mut hyphen_count = 0
  for c in s {
    if c == '-' {
      if pos != 8 && pos != 13 && pos != 18 && pos != 23 {
        raise UuidError::InvalidGuid
      }
      hyphen_count = hyphen_count + 1
      pos = pos + 1
      continue
    }
    if !is_hex_char(c) {
      raise UuidError::InvalidGuid
    }
    buf = buf + [to_lower_hex(c)]
    pos = pos + 1
  }
  if pos == 32 {
    if hyphen_count != 0 {
      raise UuidError::InvalidGuid
    }
  } else if pos == 36 {
    if hyphen_count != 4 {
      raise UuidError::InvalidGuid
    }
  } else {
    raise UuidError::InvalidGuid
  }
  if buf.length() != 32 {
    raise UuidError::InvalidGuid
  }
  { simple: buf }
}