{-# LANGUAGE TypeFamilies               #-}
{-# LANGUAGE FlexibleContexts           #-}
{-# OPTIONS -Wall #-}

--------------------------------------------------------------------------------
-- |
-- Module      :  Wumpus.Tree
-- Copyright   :  (c) Stephen Tetley 2010
-- License     :  BSD3
--
-- Maintainer  :  Stephen Tetley <stephen.tetley@gmail.com>
-- Stability   :  highly unstable
-- Portability :  GHC
--
--------------------------------------------------------------------------------

module Wumpus.Tree
  (
  -- * The type of rendered trees

    ScaleFactors
  , uniformSF
  , scaleFactors

  , drawScaledTree
  , TreeDirection(..)
  , drawScaledTreeD

  , drawScaledFamilyTree


  -- * Drawing nodes
  , charNode
  , textNode
  , circleNode
  , diskNode

  )
  where

import Wumpus.Tree.Base
import Wumpus.Tree.Design
import Wumpus.Tree.Draw
import Wumpus.Tree.TreeBuildMonad

import Wumpus.Basic.Kernel                      -- package: wumpus-basic
import Wumpus.Drawing.Dots.AnchorDots

import Wumpus.Core                              -- package: wumpus-core

import Data.VectorSpace                         -- package: vector-space




-- | Customize the size of the printed tree.
--
-- A tree is /designed/ with a height of 1 unit between 
-- parent and child nodes.
--
-- The y-scaling factor multiplies the unit height, a scaling 
-- factor of 30 represents 30 /points/.
--
-- In the horizontal, 1 unit is the smallest possible distance 
-- between child nodes.
--
type ScaleFactors u = ScalingContext u Int u

type instance DUnit (ScaleFactors u) = u



-- | Build uniform x- and y-scaling factors, i.e. @ x == y @.
--
uniformSF :: Num u => u -> ScaleFactors u
uniformSF u = ScalingContext (\x -> u * x)
                             (\y -> u * fromIntegral y) 


scaleFactors :: Num u => u -> u -> ScaleFactors u
scaleFactors sx sy = ScalingContext (\x -> sx * x)
                                    (\y -> sy * fromIntegral y)	



-- 

drawScaledTree :: (Real u, Floating u, FromPtSize u, InnerSpace (Vec2 u)) 
               => ScaleFactors u -> Point2 u -> TreeBuildAns u 
               -> TreeDrawing u
drawScaledTree scale_f ogin (tree,annos) = 
    drawTree annos $ design ogin scale_f tree



data TreeDirection = TREE_UP | TREE_DOWN | TREE_LEFT | TREE_RIGHT
  deriving (Eq,Ord,Show)

drawScaledTreeD :: (Real u, Floating u, FromPtSize u, InnerSpace (Vec2 u)) 
                => ScaleFactors u -> Point2 u 
                -> TreeDirection -> TreeBuildAns u 
                -> TreeDrawing u
drawScaledTreeD scale_f ogin tdir (tree,annos) = 
    drawTree annos $ rotTree tdir $ design ogin scale_f tree




rotTree :: (Real u, Floating u) 
        => TreeDirection -> CoordTree u a -> CoordTree u a
rotTree TREE_UP     = rotateAboutRoot pi
rotTree TREE_DOWN   = id
rotTree TREE_LEFT   = rotateAboutRoot (1.5*pi)
rotTree TREE_RIGHT  = rotateAboutRoot (0.5*pi)




drawScaledFamilyTree :: (Real u, Floating u, FromPtSize u, InnerSpace (Vec2 u)) 
               => ScaleFactors u -> Point2 u -> TreeBuildAns u 
               -> TreeDrawing u
drawScaledFamilyTree scale_f ogin (tree,annos) = 
    drawFamilyTree annos $ design ogin scale_f tree

--------------------------------------------------------------------------------
-- Drawing functions

-- | Render tree nodes with a single character.
--
--  Useful for rendering @ Data.Tree Char @.
--
charNode :: (Real u, Floating u, FromPtSize u) 
         => Char -> TreeNode u
charNode = dotChar


-- | Tree nodes with a text label.
--
-- Useful for rendering @ Data.Tree String @.
--
-- Note the width of the label is not accounted for in the 
-- /design/ of the tree. Labels with long texts may overlap.
-- Also, only a single line of text is printed - any text after 
-- the first newline character will be dropped.
--
textNode :: (Real u, Floating u, FromPtSize u) 
         => String -> TreeNode u
textNode = dotText . uptoNewline
  where
    uptoNewline = takeWhile (/='\n')

-- | Tree nodes with a stroked circle.
--
-- Suitable for printing the shape of a tree, ignoring the data.
--
circleNode :: (Floating u, FromPtSize u) 
           => RGBi -> (a -> TreeNode u)
circleNode rgb = \_ -> localize (strokeColour rgb) dotCircle


-- | Tree nodes with a filled circle.
--
-- Suitable for printing the shape of a tree, ignoring the data.
--
diskNode :: (Floating u, FromPtSize u) 
         => RGBi -> (a -> TreeNode u)
diskNode rgb = \_ -> localize (fillColour rgb) dotDisk