    {-# LINE 2 "./Graphics/Rendering/Pango/Cairo.chs" #-}
    -- -*-haskell-*-
    -- GIMP Toolkit (GTK) Cair Pango integration
    --
    -- Author : Duncan Coutts, Axel Simon
    --
    -- Created: 17 August 2005
    --
    -- Copyright (C) 2005 Duncan Coutts
    --
    -- This library is free software; you can redistribute it and/or
    -- modify it under the terms of the GNU Lesser General Public
    -- License as published by the Free Software Foundation; either
    -- version 2.1 of the License, or (at your option) any later version.
    --
    -- This library is distributed in the hope that it will be useful,
    -- but WITHOUT ANY WARRANTY; without even the implied warranty of
    -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    -- Lesser General Public License for more details.
    --
    -- |
    -- Maintainer : gtk2hs-users@lists.sourceforge.net
    -- Stability : provisional
    -- Portability : portable (depends on GHC)
    --
    --
    -- Pango specific functions to for redering with Cairo.
    --
    -- Cairo is a graphics library that supports vector graphics and image
    -- compositing that can be used with Pango. The functions in this module provide
    -- ways of rendering text in Cairo using Pango.
    --
    module Graphics.Rendering.Pango.Cairo (
      -- * Global Cairo settings.
      cairoFontMapGetDefault,
      cairoFontMapSetResolution,
      cairoFontMapGetResolution,
      cairoCreateContext,
      cairoContextSetResolution,
      cairoContextGetResolution,
      cairoContextSetFontOptions,
      cairoContextGetFontOptions,
      -- * Functions for the 'Render' monad.
      setSourceColor,
      updateContext,
      createLayout,
      updateLayout,
      showGlyphString,
      showLayoutLine,
      showLayout,
      glyphStringPath,
      layoutLinePath,
      layoutPath
      ) where

    import Control.Exception (bracket)

    import System.Glib.FFI
    import System.Glib.UTFString
    import System.Glib.GObject (wrapNewGObject, makeNewGObject,
      objectRef, objectUnref)
    import Graphics.Rendering.Pango.Types
    {-# LINE 63 "./Graphics/Rendering/Pango/Cairo.chs" #-}
    import Graphics.Rendering.Pango.BasicTypes
    {-# LINE 64 "./Graphics/Rendering/Pango/Cairo.chs" #-}
    import Graphics.Rendering.Pango.Structs ( pangoItemGetFont, Color(..) )
    import Graphics.Rendering.Pango.Layout ( layoutSetText )
    import Data.IORef

    import Graphics.Rendering.Cairo.Types as Cairo
    import qualified Graphics.Rendering.Cairo.Internal as Cairo.Internal
    import qualified Graphics.Rendering.Cairo as Cairo
    import Graphics.Rendering.Cairo.Internal (Render(Render))
    import Control.Monad.Reader

    {-# LINE 75 "./Graphics/Rendering/Pango/Cairo.chs" #-}

    --------------------
    -- Methods

    -- | Sets the specified 'Color' as the source color of the 'Render' context.
    --
    setSourceColor :: Color -> Render ()
    setSourceColor (Color red green blue) =
      Cairo.setSourceRGB
        (realToFrac red / 65535.0)
        (realToFrac green / 65535.0)
        (realToFrac blue / 65535.0)

    -- cairo_font_map_new cannot be bound due to incorrect memory management
    -- in functions like font_map_list_families that create new structures
    -- that store the font map without referencing them

    -- | Retrieve the default 'Graphics.Rendering.Pango.FontMap' that contains a
    -- list of available fonts.
    --
    -- * One purpose of creating an explicit
    -- 'Graphics.Rendering.Pango.Font.FontMap' is to set
    -- a different scaling factor between font sizes (in points, pt) and
    -- Cairo units (in pixels). The default is 96dpi (dots per inch) which
    -- corresponds to an average screen as output medium. A 10pt font will
    -- therefore scale to
    -- @10pt * (1\/72 pt\/inch) * (96 pixel\/inch) = 13.3 pixel@.
    --
    cairoFontMapGetDefault :: IO FontMap
    cairoFontMapGetDefault =
      makeNewGObject mkFontMap $ pango_cairo_font_map_get_default
    {-# LINE 106 "./Graphics/Rendering/Pango/Cairo.chs" #-}

    -- | Set the scaling factor between font size and Cairo units.
    --
    -- * Value is in dots per inch (dpi). See 'cairoFontMapGetDefault'.
    --
    cairoFontMapSetResolution :: FontMap -> Double -> IO ()
    cairoFontMapSetResolution (FontMap fm) dpi =
      withForeignPtr fm $ \fmPtr ->
      pango_cairo_font_map_set_resolution
    {-# LINE 115 "./Graphics/Rendering/Pango/Cairo.chs" #-}
        (castPtr fmPtr) (realToFrac dpi)

    -- | Ask for the scaling factor between font size and Cairo units.
    --
    -- * Value is in dots per inch (dpi). See 'cairoFontMapGetDefault'.
    --
    cairoFontMapGetResolution :: FontMap -> IO Double
    cairoFontMapGetResolution (FontMap fm) = liftM realToFrac $
      withForeignPtr fm $ \fmPtr ->
      pango_cairo_font_map_get_resolution (castPtr fmPtr)

    -- | Create a 'PangoContext'.
    --
    -- * If no 'FontMap' is specified, it uses the default 'FontMap' that
    -- has a scaling factor of 96 dpi. See 'cairoFontMapGetDefault'.
    --
    cairoCreateContext :: Maybe FontMap -> IO PangoContext
    cairoCreateContext (Just (FontMap fm)) = wrapNewGObject mkPangoContext $
      withForeignPtr fm $ \fmPtr -> -- PangoCairoFontMap /= PangoFontMap
      pango_cairo_font_map_create_context (castPtr fmPtr)
    cairoCreateContext Nothing = do
      fmPtr <- pango_cairo_font_map_get_default
    {-# LINE 137 "./Graphics/Rendering/Pango/Cairo.chs" #-}
      wrapNewGObject mkPangoContext $
        pango_cairo_font_map_create_context (castPtr fmPtr)

    -- | Set the scaling factor of the 'PangoContext'.
    --
    -- * Supplying zero or a negative value will result in the resolution value
    -- of the underlying 'FontMap' to be used. See also 'cairoFontMapGetDefault'.
    --
    cairoContextSetResolution :: PangoContext -> Double -> IO ()
    cairoContextSetResolution pc dpi =
      (\(PangoContext arg1) arg2 -> withForeignPtr arg1 $ \argPtr1 ->pango_cairo_context_set_resolution argPtr1 arg2) pc (realToFrac dpi)

    -- | Ask for the scaling factor of the 'PangoContext'.
    --
    -- * A negative value will be returned if no resolution has been set.
    -- See 'cairoContextSetResolution'.
    --
    cairoContextGetResolution :: PangoContext -> IO Double
    cairoContextGetResolution pc = liftM realToFrac $
      (\(PangoContext arg1) -> withForeignPtr arg1 $ \argPtr1 ->pango_cairo_context_get_resolution argPtr1) pc

    -- | Set Cairo font options.
    --
    -- * Apply the given font options to the context. Values set through this
    -- functions override those that are set by 'updateContext'.
    --
    cairoContextSetFontOptions :: PangoContext -> FontOptions -> IO ()
    cairoContextSetFontOptions pc fo =
      (\(PangoContext arg1) (FontOptions arg2) -> withForeignPtr arg1 $ \argPtr1 ->withForeignPtr arg2 $ \argPtr2 ->pango_cairo_context_set_font_options argPtr1 argPtr2) pc fo

    -- | Reset Cairo font options.
    --
    cairoContextResetFontOptions :: PangoContext -> IO ()
    cairoContextResetFontOptions pc =
      (\(PangoContext arg1) (FontOptions arg2) -> withForeignPtr arg1 $ \argPtr1 ->withForeignPtr arg2 $ \argPtr2 ->pango_cairo_context_set_font_options argPtr1 argPtr2) pc
        (Cairo.Internal.FontOptions nullForeignPtr)

    -- | Retrieve Cairo font options.
    --
    cairoContextGetFontOptions :: PangoContext -> IO FontOptions
    cairoContextGetFontOptions pc = do
      foPtr <- (\(PangoContext arg1) -> withForeignPtr arg1 $ \argPtr1 ->pango_cairo_context_get_font_options argPtr1) pc
      Cairo.Internal.mkFontOptions foPtr

    -- | Update a 'PangoContext' with respect to changes in a 'Render'
    -- environment.
    --
    -- * The 'PangoContext' must have been created with
    -- 'cairoCreateContext'. Any 'PangoLayout's that have been
    -- previously created with this context have to be update using
    -- 'Graphics.Rendering.Pango.Layout.layoutContextChanged'.
    --
    updateContext :: PangoContext -> Render ()
    updateContext pc = Render $ do
      cr <- ask
      liftIO $ (\(Cairo arg1) (PangoContext arg2) -> withForeignPtr arg2 $ \argPtr2 ->pango_cairo_update_context arg1 argPtr2) cr pc

    -- | Create a 'PangoLayout' within a 'Render' context.
    --
    -- * This is a convenience function that creates a new 'PangoContext'
    -- within this 'Render' context and creates a new 'PangoLayout'.
    -- If the transformation or target surface of the 'Render' context
    -- change, 'updateLayout' has to be called on this layout.
    --
    createLayout :: GlibString string => string -> Render PangoLayout
    createLayout text = Render $ do
      cr <- ask
      liftIO $ do
        layRaw <- wrapNewGObject mkPangoLayoutRaw $
                  (\(Cairo arg1) -> pango_cairo_create_layout arg1) cr
        textRef <- newIORef undefined
        let pl = (PangoLayout textRef layRaw)
        layoutSetText pl text
        return pl

    -- | Propagate changed to the 'Render' context to a 'PangoLayout'.
    --
    -- * This is a convenience function that calls 'updateContext' on the
    -- (private) 'PangoContext' of the given layout to propagate changes
    -- from the 'Render' context to the 'PangoContext' and then calls
    -- 'Graphics.Rendering.Pango.Layout.layoutContextChanged' on the layout.
    -- This function is necessary for
    -- 'createLayout' since a private 'PangoContext' is created that is
    -- not visible to the user.
    --
    updateLayout :: PangoLayout -> Render ()
    updateLayout (PangoLayout _ lay) = Render $ do
      cr <- ask
      liftIO $ (\(Cairo arg1) (PangoLayoutRaw arg2) -> withForeignPtr arg2 $ \argPtr2 ->pango_cairo_update_layout arg1 argPtr2) cr lay

    -- | Draw a glyph string.
    --
    -- * The origin of the glyphs (the left edge of the baseline) will be drawn
    -- at the current point of the cairo context.
    --
    showGlyphString :: GlyphItem -> Render ()
    showGlyphString (GlyphItem pi gs) = Render $ do
      cr <- ask
      font <- liftIO $ pangoItemGetFont pi
      liftIO $ (\(Cairo arg1) (Font arg2) (GlyphStringRaw arg3) -> withForeignPtr arg2 $ \argPtr2 ->withForeignPtr arg3 $ \argPtr3 ->pango_cairo_show_glyph_string arg1 argPtr2 argPtr3) cr font gs

    -- | Draw a 'LayoutLine'.
    --
    -- * The origin of the glyphs (the left edge of the baseline) will be drawn
    -- at the current point of the cairo context.
    --
    showLayoutLine :: LayoutLine -> Render ()
    showLayoutLine (LayoutLine _ ll) = Render $ do
      cr <- ask
      liftIO $ (\(Cairo arg1) (LayoutLineRaw arg2) -> withForeignPtr arg2 $ \argPtr2 ->pango_cairo_show_layout_line arg1 argPtr2) cr ll

    -- | Draw a 'PangoLayout'.
    --
    -- * The top-left corner of the 'PangoLayout' will be drawn at the current
    -- point of the cairo context.
    --
    showLayout :: PangoLayout -> Render ()
    showLayout (PangoLayout _ lay) = Render $ do
      cr <- ask
      liftIO $ (\(Cairo arg1) (PangoLayoutRaw arg2) -> withForeignPtr arg2 $ \argPtr2 ->pango_cairo_show_layout arg1 argPtr2) cr lay

    -- | Add the extent of a glyph string to the current path.
    --
    -- * The origin of the glyphs (the left edge of the line) will be at the
    -- current point of the cairo context.
    --
    glyphStringPath :: GlyphItem -> Render ()
    glyphStringPath (GlyphItem pi gs) = Render $ do
      cr <- ask
      font <- liftIO $ pangoItemGetFont pi
      liftIO $ (\(Cairo arg1) (Font arg2) (GlyphStringRaw arg3) -> withForeignPtr arg2 $ \argPtr2 ->withForeignPtr arg3 $ \argPtr3 ->pango_cairo_glyph_string_path arg1 argPtr2 argPtr3) cr font gs

    -- | Add the extent of a layout line to the current path.
    --
    -- * The origin of the glyphs (the left edge of the line) will be at the
    -- current point of the cairo context.
    --
    layoutLinePath :: LayoutLine -> Render ()
    layoutLinePath (LayoutLine _ ll) = Render $ do
      cr <- ask
      liftIO $ (\(Cairo arg1) (LayoutLineRaw arg2) -> withForeignPtr arg2 $ \argPtr2 ->pango_cairo_layout_line_path arg1 argPtr2) cr ll

    -- | Add the layout to the current path.
    --
    -- * Adds the top-left corner of the text to the current path. Afterwards,
    -- the path position is at the bottom-right corner of the 'PangoLayout'.
    --
    layoutPath :: PangoLayout -> Render ()
    layoutPath (PangoLayout _ lay) = Render $ do
      cr <- ask
      liftIO $ (\(Cairo arg1) (PangoLayoutRaw arg2) -> withForeignPtr arg2 $ \argPtr2 ->pango_cairo_layout_path arg1 argPtr2) cr lay

    foreign import ccall unsafe "pango_cairo_font_map_get_default"
      pango_cairo_font_map_get_default :: (IO (Ptr FontMap))

    foreign import ccall unsafe "pango_cairo_font_map_set_resolution"
      pango_cairo_font_map_set_resolution :: ((Ptr ()) -> (CDouble -> (IO ())))

    foreign import ccall unsafe "pango_cairo_font_map_get_resolution"
      pango_cairo_font_map_get_resolution :: ((Ptr ()) -> (IO CDouble))

    foreign import ccall unsafe "pango_cairo_font_map_create_context"
      pango_cairo_font_map_create_context :: ((Ptr ()) -> (IO (Ptr PangoContext)))

    foreign import ccall unsafe "pango_cairo_context_set_resolution"
      pango_cairo_context_set_resolution :: ((Ptr PangoContext) -> (CDouble -> (IO ())))

    foreign import ccall unsafe "pango_cairo_context_get_resolution"
      pango_cairo_context_get_resolution :: ((Ptr PangoContext) -> (IO CDouble))

    foreign import ccall unsafe "pango_cairo_context_set_font_options"
      pango_cairo_context_set_font_options :: ((Ptr PangoContext) -> ((Ptr FontOptions) -> (IO ())))

    foreign import ccall unsafe "pango_cairo_context_get_font_options"
      pango_cairo_context_get_font_options :: ((Ptr PangoContext) -> (IO (Ptr FontOptions)))

    foreign import ccall unsafe "pango_cairo_update_context"
      pango_cairo_update_context :: ((Ptr Cairo) -> ((Ptr PangoContext) -> (IO ())))

    foreign import ccall unsafe "pango_cairo_create_layout"
      pango_cairo_create_layout :: ((Ptr Cairo) -> (IO (Ptr PangoLayoutRaw)))

    foreign import ccall unsafe "pango_cairo_update_layout"
      pango_cairo_update_layout :: ((Ptr Cairo) -> ((Ptr PangoLayoutRaw) -> (IO ())))

    foreign import ccall unsafe "pango_cairo_show_glyph_string"
      pango_cairo_show_glyph_string :: ((Ptr Cairo) -> ((Ptr Font) -> ((Ptr GlyphStringRaw) -> (IO ()))))

    foreign import ccall unsafe "pango_cairo_show_layout_line"
      pango_cairo_show_layout_line :: ((Ptr Cairo) -> ((Ptr LayoutLineRaw) -> (IO ())))

    foreign import ccall unsafe "pango_cairo_show_layout"
      pango_cairo_show_layout :: ((Ptr Cairo) -> ((Ptr PangoLayoutRaw) -> (IO ())))

    foreign import ccall unsafe "pango_cairo_glyph_string_path"
      pango_cairo_glyph_string_path :: ((Ptr Cairo) -> ((Ptr Font) -> ((Ptr GlyphStringRaw) -> (IO ()))))

    foreign import ccall unsafe "pango_cairo_layout_line_path"
      pango_cairo_layout_line_path :: ((Ptr Cairo) -> ((Ptr LayoutLineRaw) -> (IO ())))

    foreign import ccall unsafe "pango_cairo_layout_path"
      pango_cairo_layout_path :: ((Ptr Cairo) -> ((Ptr PangoLayoutRaw) -> (IO ())))