    {-# LANGUAGE OverloadedStrings       #-}

    {-# OPTIONS -fno-warn-unused-imports #-}

    -------------------------------------------------------------------------------
    -- |
    -- Module      :  Graphics.Svg
    -- Copyright   :  (c) 2015 Jeffrey Rosenbluth
    -- License     :  BSD-style (see LICENSE)
    -- Maintainer  :  jeffrey.rosenbluth@gmail.com
    --
    -- DSL for creating SVG.
    --
    -------------------------------------------------------------------------------
    module Graphics.Svg
      ( -- * Intro
        -- $intro
        -- * Re-exports
        module Graphics.Svg.Core
      , module Graphics.Svg.Path
      , module Graphics.Svg.Elements
      , module Graphics.Svg.Attributes
      , (<>)
      -- * Rendering
      , prettyText
      ) where

    import           Data.Int               (Int64)
    import           Data.Monoid
    import           Data.Text.Lazy         as LT
    import           Data.Text.Lazy.Builder as B
    import           Graphics.Svg.Core
    import           Graphics.Svg.Attributes
    import           Graphics.Svg.Elements
    import           Graphics.Svg.Path

    prettyText :: Element -> Text
    prettyText svg = B.toLazyText $ LT.foldr go mempty text Nothing (-1)
      where
        text = renderText svg
        go c f Nothing n
          | c == '<' || c == '/' = f (Just c) n
        go c f (Just '<') n
          | c == '?' = "<?" <> f Nothing n
          | c == '!' = "<!" <> f Nothing n
          | c == '/' = "\n"
                        <> (B.fromLazyText $ LT.replicate n "  " )
                        <> "</"
                        <> f Nothing (n-1)
          | otherwise = "\n"
                        <> (B.fromLazyText $ LT.replicate (n+1)   "  " )
                        <> "<"
                        <> B.singleton c
                        <> f Nothing (n+1)
        go '>' f (Just _) n = "/>" <> f Nothing (n-1)
        go c f s n =  s' <> B.singleton c <> f Nothing n
          where  s' = maybe mempty B.singleton s

    -- $intro
    --
    -- SVG elements in Graphics-Svg are written with a postfix ‘@_@’.
    -- Some examples:
    --
    -- 'path_', 'circle_', 'color_', 'scale_'
    --
    -- Plain text is written using the @OverloadedStrings@
    -- extension, and is automatically escaped:
    --
    -- As in Graphics, elements nest by function application (unlike Graphics, there
    -- is no Monad instance for 'Element's and an 'Attribute' list is always required):
    --
    -- >>> g_ [] (text_ [] "Hello SVG")
    -- <g><text>Hello SVG</text></g>
    --
    -- and elements are juxtaposed via monoidal append:
    --
    -- >>> text_ [] "Hello" <> text_ [] "SVG"
    -- <text>Hello</text><text>SVG</text>
    --
    -- Attributes are set by providing an argument list. Each argument is set
    -- using the 'bindAttr' function or operators, '<<-' and '->>'.
    --
    -- >>> rect_ [Width_ <<- "100%", Height_ <<- "100%", "red" ->> Fill_]
    -- <rect height="100%" width="100%" fill="red"></rect>
    --
    -- Path data can be constructed using the functions in 'Graphics.Svg.Path'
    -- and combined monoidally:
    --
    -- @
    -- path_
    --   [ D_ <<- (mA 10 80 <> qA 52.5 10 95 80 <> tA 180 80 <> z)
    --   , Stroke_ <<- "blue"
    --   , Fill_ <<- "orange"
    --   ]
    -- @
    -- > <path d="M 10,80 Q 52.5,10 95,80 T 180,80 Z" stroke="blue" fill="orange"/>
    --
    -- __A slightly longer example__
    --
    -- > import Graphics.Svg
    -- >
    -- > svg :: Element -> Element
    -- > svg content =
    -- >      doctype
    -- >   <> with (svg11_ content) [Version_ <<- "1.1", Width_ <<- "300" , Height_ <<- "200"]
    -- >
    -- > contents :: Element
    -- > contents =
    -- >      rect_ [Width_ <<- "100%", Height_ <<- "100%", Fill_ <<- "red"]
    -- >   <> circle_ [Cx_ <<- "150", Cy_ <<- "100", R_ <<- "80", Fill_ <<- "green"]
    -- >   <> text_ [ X_ <<- "150", Y_ <<- "125", FontSize_ <<- "60"
    -- >            , TextAnchor_ <<- "middle", Fill_ <<- "white" ] "SVG"
    -- >
    -- >
    -- > main :: IO ()
    -- > main = do
    -- >   print $ svg contents
    -- <<http://i.imgur.com/dXu84xR.png>>
    --
    -- __The haskell logo__
    --
    -- > {-# LANGUAGE OverloadedStrings #-}
    -- >
    -- > import Graphics.Svg
    -- >
    -- > svg :: Element -> Element
    -- > svg content =
    -- >      doctype
    -- >   <> with (svg11_ content) [Version_ <<- "1.1", Width_ <<- "482", Height_ <<- "340"]
    -- >
    -- > logo :: Element
    -- > logo =
    -- >      path_ [ Fill_ <<- "#352950"
    -- >            , D_ <<- ( mA 0 340 <> lA 113 170 <> lA 0 0 <> lA 85 0
    -- >                    <> lA 198 170 <> lA 85 340 <> lA 0 340 <> z <> mA 0 340 ) ]
    -- >   <> path_ [ Fill_ <<- "#4A3A74"
    -- >            , D_ <<- ( mA 113 340 <> lA 226 170 <> lA 113 0 <> lA 198 0
    -- >                    <> lA 425 340 <> lA 340 340 <> lA 269 234 <> lA 198 340
    -- >                    <> lA 113 340 <> z <> mA 113 340 ) ]
    -- >   <> path_ [ Fill_ <<- "#7C3679"
    -- >            , D_ <<- ( mA 387 241 <> lA 350 184 <> lA 482 184 <> lA 482 241
    -- >                    <> lA 387 241 <> z <> mA 387 241 ) ]
    -- >   <> path_ [ Fill_ <<- "#7C3679"
    -- >            , D_ <<- ( mA 331 156 <> lA 293 99 <> lA 482 99 <> lA 482 156
    -- >                    <> lA 331 156 <> z <> mA 331 156 ) ]
    -- >
    -- > main :: IO ()
    -- > main = do
    -- >   print $ svg logo
    -- <<http://i.imgur.com/tuFExZl.png>>