local M = {}

function M.get_path_type(path)
  if path:sub(1, 1) == '/' then
    return 'absolute'
  elseif path:sub(1, 1) == '~' then
    return 'home'
  else
    return 'relative'
  end
end

function M.resolve(filepath, current_file)
  local path_type = M.get_path_type(filepath)

  if path_type == 'relative' then
    local base = current_file and vim.fs.dirname(current_file)
        or vim.fs.dirname(vim.api.nvim_buf_get_name(0))
    filepath = vim.fs.joinpath(base, filepath)
  end

  return vim.fs.normalize(filepath)
end

function M.strip_file_protocol(url)
  return url:gsub('^file://', '')
end

function M.is_within_wiki(filepath, wiki_root)
  local real_path = vim.fn.resolve(filepath)
  local real_root = vim.fn.resolve(wiki_root)

  local normalized_path = vim.fs.normalize(real_path)
  local normalized_root = vim.fs.normalize(real_root)

  return vim.startswith(normalized_path, normalized_root)
end

function M.validate_within_wiki(resolved_path, wiki_root, original_path)
  if not M.is_within_wiki(resolved_path, wiki_root) then
    vim.notify(
      string.format('Warning: Resolved path outside wiki root: %s', original_path),
      vim.log.levels.WARN
    )
  end
  return resolved_path
end

local ALLOWED_SCHEMES = {
  http = true,
  https = true,
  file = true,
}

function M.validate_url_scheme(url)
  local scheme = url:match('^([a-zA-Z]+)://')
  if scheme and not ALLOWED_SCHEMES[scheme:lower()] then
    return false, string.format('URL scheme not allowed: %s', scheme)
  end
  return true, nil
end

return M