-- Shared helper functions for use inside snippet function_node()/dynamic_node()

local M = {}

function M.today()
  return os.date("%Y-%m-%d")
end

function M.timestamp()
  return os.date("| %Y-%m-%d %H:%M | ")
end

function M.clipboard_or(default)
  return function()
    local clip = vim.fn.getreg "+"
    return clip ~= "" and clip or default
  end
end

-- Space padding to center `text` between fixed-width markers (e.g. "###")
-- so the whole line (markers + padding + text) is exactly `width` chars.
local function side_pad(text, width, marker_len)
  local interior = width - marker_len * 2
  local pad = math.max(interior - #text, 0)
  local left = math.floor(pad / 2)
  local right = pad - left
  return left, right
end

-- Use as f(util.pad_left(100, 3), { N }) where N is the node index holding
-- the text to center, placed right after the opening marker.
function M.pad_left(width, marker_len)
  width, marker_len = width or 100, marker_len or 3
  return function(args)
    local left = side_pad(args[1][1] or "", width, marker_len)
    return string.rep(" ", left)
  end
end

-- Companion to pad_left(), placed right before the closing marker.
function M.pad_right(width, marker_len)
  width, marker_len = width or 100, marker_len or 3
  return function(args)
    local _, right = side_pad(args[1][1] or "", width, marker_len)
    return string.rep(" ", right)
  end
end

return M