local telescope = require('telescope')

-- Goals:
-- 1. You pick a directory
-- 2. We `git ls-files` in that directory ONCE and ONLY ONCE to get the results.
-- 3. You can fuzzy find those results w/ fzf
-- 4. Select one and go to file.


--[[
ls_files_job.start()
fzf_job.stdin = ls_files_job.stdout

  self.stdin = vim.loop.new_pipe(false)
  -> self.stdin = finder.stdout


  -- Finder:
  intermediary_pipe = self.stdout

  -- repeat send this pipe when we want to get new filtering
  self.stdin = intermediary_pipe


  -- Filter + Sort
  ok, we could do scoring + cutoff and have that always be the case.

  OR

  filter takes a function, signature (prompt: str, line: str): number

  => echo $line | fzf --filter "prompt"
      return stdout != ""

  => lua_fuzzy_finder(prompt, line) return true if good enough

  TODO: Rename everything to be more clear like the name below.
  IFilterSorterAbstractFactoryGeneratorv1ProtoBeta

--]]

local string_distance = require('telescope.algos.string_distance')

local file_finder = telescope.finders.new {
  fn_command = function(self, prompt)
    -- todo figure out how to cache this later
    if false then
      if self[prompt] == nil then
        self[prompt] = nil
      end

      return self[prompt]
    else
      return 'git ls-files'
    end
  end,
}

local file_sorter = telescope.sorters.new {
  scoring_function = function(self, prompt, line)
    if prompt == '' then return 0 end
    if not line then return -1 end

    local dist = string_distance(prompt, line)
    -- if dist > (0.75 * #line) and #prompt > 3 then
    --   return -1
    -- end

    return dist
  end
}

local file_previewer = telescope.previewers.vim_buffer

local file_picker = telescope.pickers.new {
  previewer = file_previewer
}

file_picker:find {
  prompt = 'Find File',
  finder = file_finder,
  sorter = file_sorter,
}