{-# LINE 2 "./Graphics/Rendering/Pango/Font.chs" #-}
-- -*-haskell-*-
-- GIMP Toolkit (GTK) - text layout functions: Font
--
-- Author : Axel Simon
--
-- Created: 16 October 2005
--
-- Copyright (C) 1999-2005 Axel Simon
--
-- 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)
--
-- Fonts. The selection of an appropriate font to render text becomes a
-- substantial task in the presence of Unicode where a single font does not
-- cover the whole range of possible characters. Pango provides several
-- concepts to find appropriate fonts and to query information about them:
--
-- * 'FontDescription': Font descriptions provide a way to query and state
-- requirements on
-- fonts. This data structure has several fields describing different
-- characteristics of a font. Each of these fields can be set of left
-- unspecified.
--
-- * 'FontMap' : A font map represents the set of fonts available for a
-- particular rendering system. In particular this map defines the
-- relation between font size and pixel size in terms of the output medium.
--
-- * 'FontFamily' : A font family represents a set of fonts that have
-- related faces, that is, their faces share a common design, but differ
-- in slant, weight, width and other aspects.
--
-- * 'FontFace': A face is a specific font where all characteristics are
-- fixed except for the size.
--
-- * 'Font': A font in the underlying rendering system.
--
-- * 'FontMetrics': Information about the font that will be used to render
-- a specific 'Context' or 'PangoItem'.
--
module Graphics.Rendering.Pango.Font (
  -- Functions to manage font descriptions.
  module Graphics.Rendering.Pango.Description,
  -- Font metrics.
  FontMap,
  FontMapClass,
  pangoFontMapListFamilies,
  FontFamily,
  FontFamilyClass,

  pangoFontFamilyIsMonospace,

  pangoFontFamilyListFaces,
  FontFace,
  FontFaceClass,

  pangoFontFaceListSizes,

  pangoFontFaceDescribe,
  Font,
  FontClass,
  ) where

import Control.Monad (liftM)
import qualified Data.Text as T (unpack)

import System.Glib.FFI
import System.Glib.UTFString
import System.Glib.GObject (makeNewGObject)
import Graphics.Rendering.Pango.BasicTypes
{-# LINE 83 "./Graphics/Rendering/Pango/Font.chs" #-}
import Graphics.Rendering.Pango.Types
{-# LINE 84 "./Graphics/Rendering/Pango/Font.chs" #-}
import Graphics.Rendering.Pango.Enums (FontMetrics)
import Graphics.Rendering.Pango.Description
import Graphics.Rendering.Pango.Structs


{-# LINE 89 "./Graphics/Rendering/Pango/Font.chs" #-}


-- | Ask for the different font families that a particular back-end supports.
--
-- * The 'FontMap' can be acquired by calling
-- 'Graphics.Rendering.Pango.Cairo.cairoFontMapGetDefault'.
--
pangoFontMapListFamilies :: FontMap -> IO [FontFamily]
pangoFontMapListFamilies fm = alloca $ \arrPtrPtr -> alloca $ \sizePtr -> do
  (\(FontMap arg1) arg2 arg3 -> withForeignPtr arg1 $ \argPtr1 ->pango_font_map_list_families argPtr1 arg2 arg3) fm arrPtrPtr sizePtr
  arrPtr <- peek arrPtrPtr
  size <- peek sizePtr
  ffsPtr <- peekArray (fromIntegral size)
     (castPtr arrPtr::Ptr (Ptr FontFamily)) -- c2hs is wrong here
  g_free (castPtr arrPtr)
  mapM (makeNewGObject mkFontFamily . return . castPtr) ffsPtr

instance Show FontFamily where
  show ff = T.unpack . unsafePerformIO $ do
    strPtr <- (\(FontFamily arg1) -> withForeignPtr arg1 $ \argPtr1 ->pango_font_family_get_name argPtr1) ff
    peekUTFString strPtr


-- | Ask if the given family contains monospace fonts.
--
-- * A monospace font is a font designed for text display where the
-- characters form a regular grid. For Western languages this would
-- mean that the advance width of all characters are the same, but
-- this categorization also includes Asian fonts which include
-- double-width characters: characters that occupy two grid cells.
--
-- * The best way to find out the grid-cell size is to query the members
-- of the according 'FontMetrics' structure.
--
pangoFontFamilyIsMonospace :: FontFamily -> Bool
pangoFontFamilyIsMonospace ff = unsafePerformIO $
  liftM toBool $ (\(FontFamily arg1) -> withForeignPtr arg1 $ \argPtr1 ->pango_font_family_is_monospace argPtr1) ff


-- | Ask for the faces contained in a particular family.
--
-- * Asks for all font faces in the given family. The faces in a family
-- share a common design, but differ in slant, weight, width and other
-- aspects. For example, the font family "Sans" contains several fonts
-- such as Helvetica and Arial.
--
pangoFontFamilyListFaces :: FontFamily -> IO [FontFace]
pangoFontFamilyListFaces ff = alloca $ \arrPtrPtr -> alloca $ \sizePtr -> do
  (\(FontFamily arg1) arg2 arg3 -> withForeignPtr arg1 $ \argPtr1 ->pango_font_family_list_faces argPtr1 arg2 arg3) ff arrPtrPtr sizePtr
  arrPtr <- peek arrPtrPtr
  size <- peek sizePtr
  ffsPtr <- peekArray (fromIntegral size)
     (castPtr arrPtr::Ptr (Ptr FontFace)) -- c2hs is wrong here
  g_free (castPtr arrPtr)
  mapM (makeNewGObject mkFontFace . return . castPtr) ffsPtr

instance Show FontFace where
  show ff = T.unpack . unsafePerformIO $ do
    strPtr <- (\(FontFace arg1) -> withForeignPtr arg1 $ \argPtr1 ->pango_font_face_get_face_name argPtr1) ff
    peekUTFString strPtr


-- | Ask for available sizes of this font face.
--
-- * List the available sizes for a font. This is only applicable to bitmap
-- fonts since all other fonts can be scaled arbitrarily. For scalable
-- fonts, this function returns @Nothing@. The sizes returned are in
-- ascending order, their unit is points (1\/72 inch).
--
pangoFontFaceListSizes :: FontFace -> IO (Maybe [Double])
pangoFontFaceListSizes ff = alloca $ \arrPtrPtr -> alloca $ \sizePtr -> do
  (\(FontFace arg1) arg2 arg3 -> withForeignPtr arg1 $ \argPtr1 ->pango_font_face_list_sizes argPtr1 arg2 arg3) ff arrPtrPtr sizePtr
  arrPtr <- peek arrPtrPtr
  size <- peek sizePtr
  if arrPtr==nullPtr then return Nothing else do
    sizes <- peekArray (fromIntegral size) arrPtr
    g_free (castPtr arrPtr)
    return (Just (map intToPu sizes))


-- | Ask for a description of this face.
--
-- * Returns the family, style, variant, weight and stretch of a 'FontFace'.
-- The size field of the resulting font description will be unset.
--
pangoFontFaceDescribe :: FontFace -> IO FontDescription
pangoFontFaceDescribe ff = do
  fdPtr <- (\(FontFace arg1) -> withForeignPtr arg1 $ \argPtr1 ->pango_font_face_describe argPtr1) ff
  makeNewFontDescription fdPtr

foreign import ccall unsafe "pango_font_map_list_families"
  pango_font_map_list_families :: ((Ptr FontMap) -> ((Ptr (Ptr FontFamily)) -> ((Ptr CInt) -> (IO ()))))

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

foreign import ccall unsafe "pango_font_family_get_name"
  pango_font_family_get_name :: ((Ptr FontFamily) -> (IO (Ptr CChar)))

foreign import ccall unsafe "pango_font_family_is_monospace"
  pango_font_family_is_monospace :: ((Ptr FontFamily) -> (IO CInt))

foreign import ccall unsafe "pango_font_family_list_faces"
  pango_font_family_list_faces :: ((Ptr FontFamily) -> ((Ptr (Ptr FontFace)) -> ((Ptr CInt) -> (IO ()))))

foreign import ccall unsafe "pango_font_face_get_face_name"
  pango_font_face_get_face_name :: ((Ptr FontFace) -> (IO (Ptr CChar)))

foreign import ccall unsafe "pango_font_face_list_sizes"
  pango_font_face_list_sizes :: ((Ptr FontFace) -> ((Ptr (Ptr CInt)) -> ((Ptr CInt) -> (IO ()))))

foreign import ccall unsafe "pango_font_face_describe"
  pango_font_face_describe :: ((Ptr FontFace) -> (IO (Ptr FontDescription)))