local Gio = require("lgi").Gio

local _filesystem = {}

--- Get a list of files from a given directory.
-- @string path The directory to search.
-- @tparam[opt] table exts Specific extensions to limit the search to. eg:`{ "jpg", "png" }`
--   If ommited, all files are considered.
-- @bool[opt=false] recursive List files from subdirectories
-- @staticfct bling.helpers.filesystem.get_random_file_from_dir
function _filesystem.list_directory_files(path, exts, recursive)
  recursive = recursive or false
  local files, valid_exts = {}, {}

  -- Transforms { "jpg", ... } into { [jpg] = #, ... }
  if exts then
    for i, j in ipairs(exts) do
      valid_exts[j:lower()] = i
    end
  end

  -- Build a table of files from the path with the required extensions
  local file_list = Gio.File.new_for_path(path):enumerate_children("standard::*", 0)
  if file_list then
    for file in function() return file_list:next_file() end do
      local file_type = file:get_file_type()
      if file_type == "REGULAR" then
        local file_name = file:get_display_name()
        if not exts or valid_exts[file_name:lower():match(".+%.(.*)$") or ""] then table.insert(files, file_name) end
      elseif recursive and file_type == "DIRECTORY" then
        local file_name = file:get_display_name()
        files = gears.table.join(files, list_directory_files(file_name, exts, recursive))
      end
    end
  end

  return files
end

return _filesystem
