from lepl import *
from lepl.graph import SimpleWalker

class Table(Node): pass
class Variable(Node): pass
class Value(Node): pass
class Query(Node): pass
class Logical(Node): pass
class Boolean(Node): pass
class Statement(Node): pass

statement = Delayed()
logicalstatement   = Delayed()
booleanstatement   = Delayed()
number = Digit()[1:,...]
variable = Regexp(r'[a-zA-Z][a-zA-Z0-9]*')	> Variable
table = Regexp(r'[a-zA-Z][a-zA-Z0-9]*')		> Table
string = Regexp(r'[\s\w\d]*')
spaces = Drop(Regexp(r'\s*'))

with Separator(spaces):
	value = number | '"' & string & '"'	> Value
	term = value | variable	
	booleanstatement += (statement & '&' & booleanstatement) | (statement & '|' & booleanstatement) | statement	> Boolean
	logicalstatement += term & Any('<>=~') & logicalstatement | term				> Logical
	statement += '(' & booleanstatement & ')' | logicalstatement
	query = table & '?' & booleanstatement 								> Query

parser = query.parse_string

ast = parser("materials ? 30 < shearmodulus < 50 & meltingtemp > 460 & (tensilestrength > 4000 | poissonsmodulus < 14)")
# print parser("objects ? name ~ \"bicycle\" ")[0]

# print SimpleWalker(ast)

# print "Table is '%s'" % ast[0].Table[0]

table = ast[0].Table[0][0]

print "Searching table structure '%s'" % table

matchneeded = False
value1 = 0
value2 = 0
comparator = 0
logic = " AND "

def extr(a):
	global matchneeded
	global value1
	global value2
	global comparator
	global logic

	s = ""

	for child in a:
		if type(child) in (Boolean, Logical, Statement):
			s += extr(child)
		elif type(child) in (Variable, Value):
			if matchneeded:
				value2 = child[0]
				matchneeded = False
				s += " %s ( %s %s %s ) " % (logic, value1, comparator, value2)
				value1 = value2
			else:
				value1 = child[0]

		elif child == '&':
			logic = " AND "
		elif child == '|':
			logic = " OR "
		elif child in ('<', '>', '~', '='):
			matchneeded = True
			comparator = child
		elif child in ('(', ')'):
			s += child
		else:
			print "Unrecognized token: '%s'" % child

	return s

print "arr: " + extr(ast[0].Boolean[0])

# print [child for child in ast[0].Boolean[0]]