from __future__ import print_function

import unittest, pprint, traceback
from simpleparse.parser import Parser
from simpleparse import printers


def rcmp( table1, table2 ):
    """Silly utility function to get around text search object lack of __cmp__"""
    if len(table1) != len(table2):
        return 0
    else:
        for x,y in zip(table1, table2):
            if not _rcmp( x,y):
                return 0
        return 1
def _rcmp( item1, item2 ):
    if len(item1) != len(item2):
        return 0
    if item1[1] in (204,):
        if cmp(item1[:2], item2[:2]) != 0:
            return 0
        try:
            if not rcmp( item1[2][0][item1[2][1]], item2[2][0][item2[2][1]]):
                return 0
        except TypeError:
            print(item1)
            print(item2)
    elif item1[1] == 207:
        if item2[:2] != item2[:2]:
            return 0
        if not rcmp( item1[2], item2[2]):
            return 0
    else:
        for a,b in zip(item1, item2):
            if hasattr(a,'match') and hasattr(b,'match'):
                if not (a.match == b.match and a.translate == b.translate):
                    return 0
            elif a != b:
                return 0
    return 1
            
            

class OptimisationTests(unittest.TestCase):
    def testTermCompression( self ):
        """Test that unreported productions are compressed

        Term compression is basically an inlining of terminal
        expressions into the calling table.  At the moment
        the terminal expressions are all duplicated, which may
        balloon the size of the grammar, not sure if this will
        be an actual problem.  As written, this optimization
        should provide a significant speed up, but there may
        the even more of a speed up if we allow for sharing
        the terminal tuples as well.

        This:
            a:=b <b>:= -c* c:='this'
        Should eventually compress to this:
            a := -'this'*
        """
        failures = []
        for first, second in [
            ("""a:=b <b>:= -c* c:='this'""", """a := -'this'*"""),
            ("""a:=b >b<:= c c:= 'this'""", """a := c c:= 'this'"""),
            ("""a:=b >b<:= c <c>:= 'this'""", """a := 'this'"""),
            ("""a:=b >b<:= c+ <c>:= 'this'""", """a := 'this'+"""),
            # The following will never work, so eventually may raise
            # an error or at least give a warning!
            ("""a:=b,c >b<:= c+ <c>:= 'this'""", """a := 'this'+,'this'"""),
            ("""a:=b/c >b<:= c+ <c>:= 'this'""", """a := 'this'+/'this'"""),
            # This is requiring group-compression, which isn't yet written
            ("""a:=-b/c >b<:= c+ <c>:= 'this'""", """a := -'this'+/'this'"""),
            ("""a    := (table1 / table2 / any_line)*
  <any_line> := ANY*, EOL
  <ANY>      := -EOL
  <EOL>      := '\n'
  table1 := 'a'
  table2 := 'b'
  """, """a    := (table1 / table2 / (-'\n'*, '\n'))*
    table1 := 'a'
  table2 := 'b'
"""),
            ("""a:= b,c <b>:= -c* <c>:= '\n'""", """a := -'\n'*,'\n'"""),
            
        ]:
            pFirst = Parser( first, "a")
            pSecond = Parser( second, "a")
            tFirst = pFirst.buildTagger()
            tSecond = pSecond.buildTagger()
            if not rcmp( tFirst , tSecond):
                tFirstRepr = pprint.pformat(tFirst)
                tSecondRepr = pprint.pformat(tSecond)
                failures.append( """%(first)r did not produce the same parser as %(second)r\n\t%(tFirstRepr)s\n\t%(tSecondRepr)s"""%locals())
        if failures:
            raise ValueError( "\n".join(failures))
    def testTermSharing( self ):
        """Test that shared terminal productions are using the same parser"""
        first =""" a := b,b >b<:= d d:= 'this'"""
        pFirst = Parser( first, "a")
        tFirst = pFirst.buildTagger()
        b,c = tFirst
        assert b is c, """Not sharing the same tuple for b and c instances"""
    def testNoReportPassDown( self ):
        """Test that a non-reporting production does not produce reporting sub-productions"""
        first =""" a := b <b>:= d,e d:= e e:= 'this'"""
        second =""" a := 'this' """
        assert Parser( first, 'a').parse( 'thisthis' ) == (1,[
        ],8)
        
    def testNameCollapseForSimple( self ):
        """Test that a name reference, given a single-item reporting avoids extra table"""
        first =""" a := b,b b:= 'this'"""
        # The result should be...
        expected = ( ('b',21,'this'),('b',21,'this'))
        table = Parser( first, 'a').buildTagger( )
        assert table == expected, "%s != %s"%(
            pprint.pformat( table),
            pprint.pformat(expected),
        )
        
def getSuite():
    return unittest.makeSuite(OptimisationTests,'test')

if __name__ == "__main__":
    unittest.main(defaultTest="getSuite")