-- Implicit CAD. Copyright (C) 2011, Christopher Olah (chris@colah.ca)
-- Copyright 2016, Julia Longtin (julial@turinglace.com)
-- Released under the GNU AGPLV3+, see LICENSE

-- This module exists to re-export a coherent set of functions to define
-- Data.Text.Lazy builders with.

module Graphics.Implicit.Export.TextBuilderUtils  
    (
     -- Values from Data.Text.Lazy
     Text,
     pack,
     -- Values from Data.Text.Lazy.Builder, as well as some special builders
     Builder,
     toLazyText,
     fromLazyText,
     buildInt,
     -- Serialize a float in full precision
     bf,
     -- Serialize a float with four decimal places
     buildTruncFloat,
     -- Values from Data.Monoid
     (<>),
     mconcat,
     mempty
    ) where

import Prelude (Int, Maybe(Nothing, Just), ($))

import Data.Text.Lazy (Text, pack)
-- We manually redefine this operator to avoid a dependency on base >= 4.5
-- This will become unnecessary later.
import Data.Monoid (Monoid, mappend, mconcat, mempty)

import Data.Text.Internal.Lazy (defaultChunkSize)
import Data.Text.Lazy.Builder (Builder, toLazyTextWith, fromLazyText)
import Data.Text.Lazy.Builder.RealFloat (formatRealFloat, FPFormat(Exponent, Fixed))
import Data.Text.Lazy.Builder.Int (decimal)

import Graphics.Implicit.Definitions (ℝ)

-- The chunk size for toLazyText is very small (128 bytes), so we export
-- a version with a much larger size (~16 K)
toLazyText :: Builder -> Text
toLazyText = toLazyTextWith defaultChunkSize

bf, buildTruncFloat :: ℝ -> Builder

bf = formatRealFloat Exponent Nothing

buildTruncFloat = formatRealFloat Fixed $ Just 4

buildInt :: Int -> Builder
buildInt = decimal

-- This is directly copied from base 4.5.1.0
infixr 6 <>
(<>) :: Monoid m => m -> m -> m
(<>) = mappend