content: {-# LANGUAGE TemplateHaskell #-}
  {-# OPTIONS_GHC -fno-warn-orphans #-}
  
  {-| Unittests for Ganeti.Htools.Graph
  
  -}
  
  {-
  
  Copyright (C) 2009, 2010, 2011, 2012 Google Inc.
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are
  met:
  
  1. Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
  
  2. Redistributions in binary form must reproduce the above copyright
  notice, this list of conditions and the following disclaimer in the
  documentation and/or other materials provided with the distribution.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  -}
  
  module Test.Ganeti.HTools.Graph (testHTools_Graph) where
  
  import Test.QuickCheck
  import Test.HUnit
  
  import Test.Ganeti.TestHelper
  import Test.Ganeti.TestCommon
  
  import Ganeti.HTools.Graph
  
  import qualified Data.Graph as Graph
  import qualified Data.IntMap as IntMap
  
  {-# ANN module "HLint: ignore Use camelCase" #-}
  
  data TestableGraph = TestableGraph Graph.Graph deriving (Show)
  data TestableClique = TestableClique Graph.Graph deriving (Show)
  
  -- | Generate node bounds and edges for an undirected graph.
  -- A graph is undirected if for every (a, b) edge there is a
  -- corresponding (b, a) one.
  undirEdges :: Gen (Graph.Bounds, [Graph.Edge])
  undirEdges = sized undirEdges'
    where
      undirEdges' 0 = return ((0, 0), [])
      undirEdges' n = do
        maxv <- choose (1, n)
        edges <- listOf1 $ do
          i <- choose (0, maxv)
          j <- choose (0, maxv) `suchThat` (/= i)
          return [(i, j), (j, i)]
        return ((0, maxv), concat edges)
  
  -- | Generate node bounds and edges for a clique.
  -- In a clique all nodes are directly connected to each other.
  cliqueEdges :: Gen (Graph.Bounds, [Graph.Edge])
  cliqueEdges = sized cliqueEdges'
    where
      cliqueEdges' 0 = return ((0, 0), [])
      cliqueEdges' n = do
        maxv <- choose (0, n)
        let edges = [(x, y) | x <- [0..maxv], y <- [0..maxv], x /= y]
        return ((0, maxv), edges)
  
  instance Arbitrary TestableGraph where
    arbitrary = do
      (mybounds, myedges) <- undirEdges
      return . TestableGraph $ Graph.buildG mybounds myedges
  
  instance Arbitrary TestableClique where
    arbitrary = do
      (mybounds, myedges) <- cliqueEdges
      return . TestableClique $ Graph.buildG mybounds myedges
  
  -- | Check that the empty vertex color map is empty.
  case_emptyVertColorMapNull :: Assertion
  case_emptyVertColorMapNull = assertBool "" $ IntMap.null emptyVertColorMap
  
  -- | Check that the empty vertex color map is zero in size.
  case_emptyVertColorMapEmpty :: Assertion
  case_emptyVertColorMapEmpty =
    assertEqual "" 0 $ IntMap.size emptyVertColorMap
  
  -- | Check if each two consecutive elements on a list
  -- respect a given condition.
  anyTwo :: (a -> a -> Bool) -> [a] -> Bool
  anyTwo _ [] = True
  anyTwo _ [_] = True
  anyTwo op (x:y:xs) = (x `op` y) && anyTwo op (y:xs)
  
  -- | Check order of vertices returned by verticesByDegreeAsc.
  prop_verticesByDegreeAscAsc :: TestableGraph -> Bool
  prop_verticesByDegreeAscAsc (TestableGraph g) = anyTwo (<=) (degrees asc)
      where degrees = map (length . neighbors g)
            asc = verticesByDegreeAsc g
  
  -- | Check order of vertices returned by verticesByDegreeDesc.
  prop_verticesByDegreeDescDesc :: TestableGraph -> Bool
  prop_verticesByDegreeDescDesc (TestableGraph g) = anyTwo (>=) (degrees desc)
      where degrees = map (length . neighbors g)
            desc = verticesByDegreeDesc g
  
  -- | Check that our generated graphs are colorable
  prop_isColorableTestableGraph :: TestableGraph -> Bool
  prop_isColorableTestableGraph (TestableGraph g) = isColorable g
  
  -- | Check that our generated graphs are colorable
  prop_isColorableTestableClique :: TestableClique -> Bool
  prop_isColorableTestableClique (TestableClique g) = isColorable g
  
  -- | Check that the given algorithm colors a clique with the same number of
  -- colors as the vertices number.
  prop_colorClique :: (Graph.Graph -> VertColorMap) -> TestableClique -> Property
  prop_colorClique alg (TestableClique g) = numvertices ==? numcolors
      where numcolors = (IntMap.size . colorVertMap) $ alg g
            numvertices = length (Graph.vertices g)
  
  -- | Specific check for the LF algorithm.
  prop_colorLFClique :: TestableClique -> Property
  prop_colorLFClique = prop_colorClique colorLF
  
  -- | Specific check for the Dsatur algorithm.
  prop_colorDsaturClique :: TestableClique -> Property
  prop_colorDsaturClique = prop_colorClique colorDsatur
  
  -- | Specific check for the Dcolor algorithm.
  prop_colorDcolorClique :: TestableClique -> Property
  prop_colorDcolorClique = prop_colorClique colorDcolor
  
  -- Check that all nodes are colored.
  prop_colorAllNodes :: (Graph.Graph -> VertColorMap)
                     -> TestableGraph
                     -> Property
  prop_colorAllNodes alg (TestableGraph g) = numvertices ==? numcolored
      where numcolored = IntMap.foldr ((+) . length) 0 vcMap
            vcMap = colorVertMap $ alg g
            numvertices = length (Graph.vertices g)
  
  -- | Specific check for the LF algorithm.
  prop_colorLFAllNodes :: TestableGraph -> Property
  prop_colorLFAllNodes = prop_colorAllNodes colorLF
  
  -- | Specific check for the Dsatur algorithm.
  prop_colorDsaturAllNodes :: TestableGraph -> Property
  prop_colorDsaturAllNodes = prop_colorAllNodes colorDsatur
  
  -- | Specific check for the Dcolor algorithm.
  prop_colorDcolorAllNodes :: TestableGraph -> Property
  prop_colorDcolorAllNodes = prop_colorAllNodes colorDcolor
  
  -- | Check that no two vertices sharing the same edge have the same color.
  prop_colorProper :: (Graph.Graph -> VertColorMap) -> TestableGraph -> Bool
  prop_colorProper alg (TestableGraph g) = all isEdgeOk $ Graph.edges g
      where isEdgeOk :: Graph.Edge -> Bool
            isEdgeOk (v1, v2) = color v1 /= color v2
            color v = cMap IntMap.! v
            cMap = alg g
  
  -- | Specific check for the LF algorithm.
  prop_colorLFProper :: TestableGraph -> Bool
  prop_colorLFProper = prop_colorProper colorLF
  
  -- | Specific check for the Dsatur algorithm.
  prop_colorDsaturProper :: TestableGraph -> Bool
  prop_colorDsaturProper = prop_colorProper colorDsatur
  
  -- | Specific check for the Dcolor algorithm.
  prop_colorDcolorProper :: TestableGraph -> Bool
  prop_colorDcolorProper = prop_colorProper colorDcolor
  
  -- | List of tests for the Graph module.
  testSuite "HTools/Graph"
              [ 'case_emptyVertColorMapNull
              , 'case_emptyVertColorMapEmpty
              , 'prop_verticesByDegreeAscAsc
              , 'prop_verticesByDegreeDescDesc
              , 'prop_colorLFClique
              , 'prop_colorDsaturClique
              , 'prop_colorDcolorClique
              , 'prop_colorLFAllNodes
              , 'prop_colorDsaturAllNodes
              , 'prop_colorDcolorAllNodes
              , 'prop_colorLFProper
              , 'prop_colorDsaturProper
              , 'prop_colorDcolorProper
              , 'prop_isColorableTestableGraph
              , 'prop_isColorableTestableClique
              ]
  