---
---Description of the module.
---@class Format
local Format = {
  ---single-line comment
  classname = "HMFormat"
}

-------------------------------------------------------------------------------
---Format the number
---@param n number the number
---@param decimal number
---@return number --formated number
function Format.formatNumber(n, decimal)
  local separator = " "
  if n == nil then return 0 end
  --return tostring(math.floor(n)):reverse():gsub("(%d%d%d)","%1 "):gsub(" (%-?)$","%1"):reverse()
  if decimal == nil then decimal = 2 end
  if n > 100 and decimal > 1 then decimal = 1 end
  if n > 1000 then decimal = 0 end
  local left,num,right = string.match(Format.round(n, decimal),'^([^%d]*%d)(%d*)(.-)$')
  if num == nil then return 0 end
  if left == nil then left = "" end
  if right == nil then right = "" end
  return left..(num:reverse():gsub('(%d%d%d)','%1'..separator):reverse())..right
end

-------------------------------------------------------------------------------
---Format the number
---@see http://lua-users.org/wiki/FormattingNumbers
---@details Round up unless the number is lower than x.02, then round down.
---  Since this is used mostly to format factory/resource numbers this gives
---  the minimum necessary amount rounded to a proper number of decimal places,
---  but drops small surpluses from floating point.
---@param val number the number
---@param decimal number
---@return number --formated number
function Format.round(val, decimal)
  if (decimal) then
    if decimal >= 0 then
      return math.ceil( (val * 10^decimal)) / (10^decimal)
    else
      local decimal = math.abs(decimal)
      return math.floor( (val * 10^decimal)) / (10^decimal)
    end
  else
    return math.ceil(val)
  end
end

-------------------------------------------------------------------------------
---Format the number
---@param value number the number
---@param suffix? string
---@return string --formated number
function Format.formatNumberKilo(value, suffix)
  if suffix == nil then suffix = "" end
  if value == nil then
    return 0
  elseif value < 1000 then
    return Format.formatNumber(value).." "..suffix
  elseif (value / 1000) < 1000 then
    return math.ceil(value*10 / 1000)/10 .. " k" ..suffix
  elseif (value / (1000*1000)) < 1000 then
    return math.ceil(value*10 / (1000*1000))/10 .. " M" ..suffix
  else
    return math.ceil(value*10 / (1000*1000*1000))/10 .. " G" ..suffix
  end
end

-------------------------------------------------------------------------------
---Format the number
---@param num number
---@return number
function Format.formatPercent(num)
  local mult = 10^3
  return math.floor(num * mult + 0.5) / 10
end

-------------------------------------------------------------------------------
---Return decimal from a string, 0.00 return 2 decimal
---@param value string
---@return number
function Format.decimalFromString(value)
  local _, c = value:gsub("0","")
  return c - 1
end
-------------------------------------------------------------------------------
---Format number for factory
---@param number number
---@return number
function Format.formatNumberFactory(number)
  local format_number = User.getPreferenceSetting("format_number_factory")
  local decimal = Format.decimalFromString(format_number)
  return Format.formatNumber(number, decimal)
end

-------------------------------------------------------------------------------
---Format number for element product or ingredient
---@param number number
---@return number
function Format.formatNumberElement(number)
  local format_number = User.getPreferenceSetting("format_number_element")
  local decimal = Format.decimalFromString(format_number)
  return Format.formatNumber(number, decimal)
end
return Format
