###############################################################################
#                                                                             #
# This file is part of IfcOpenShell.                                          #
#                                                                             #
# IfcOpenShell is free software: you can redistribute it and/or modify        #
# it under the terms of the Lesser GNU General Public License as published by #
# the Free Software Foundation, either version 3.0 of the License, or         #
# (at your option) any later version.                                         #
#                                                                             #
# IfcOpenShell 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                #
# Lesser GNU General Public License for more details.                         #
#                                                                             #
# You should have received a copy of the Lesser GNU General Public License    #
# along with this program. If not, see <http://www.gnu.org/licenses/>.        #
#                                                                             #
###############################################################################

import sys
import string
import operator
import itertools

from pyparsing import *

try: from functools import reduce
except: pass

class Expression:
    def __init__(self, contents):
        self.contents = contents[0]
    def __repr__(self):
        if self.op is None: return repr(self.contents)
        c = [isinstance(c,str) and c or str(c) for c in self.contents]
        if "%s" in self.op: return self.op % (" ".join(c))
        else: return "(%s)" % (" %s "%self.op).join(c)
    def __iter__(self):
        return self.contents.__iter__()

class Union(Expression):
    op = "|"

class Concat(Expression):
    op = "+"

class Optional(Expression):
    op = "Optional(%s)"

class Repeated(Expression):
    op = "ZeroOrMore(%s)"

class Term(Expression):
    op = None

class Keyword:
    def __init__(self, contents):
        self.contents = contents[0]
    def __repr__(self):
        return self.contents

class Terminal:
    def __init__(self, contents):
        self.contents = contents[0]
        s = self.contents
        self.is_keyword = len(s) >= 4 and s[0::len(s)-1] == '""' and \
            all(c in alphanums+"_" for c in s[1:-1])
    def __repr__(self):
        ty = "CaselessKeyword" if self.is_keyword else "CaselessLiteral"
        return "%s(%s)" % (ty, self.contents)


LPAREN = Suppress("(")
RPAREN = Suppress(")")
LBRACK = Suppress("[")
RBRACK = Suppress("]")
LBRACE = Suppress("{")
RBRACE = Suppress("}")
EQUALS = Suppress("=")
VBAR   = Suppress("|")
PERIOD = Suppress(".")
HASH   = Suppress("#")

identifier = Word(alphanums+"_")
keyword    = Word(alphanums+"_").setParseAction(Keyword)
expression = Forward()
optional   = Group(LBRACK + expression + RBRACK).setParseAction(Optional)
repeated   = Group(LBRACE + expression + RBRACE).setParseAction(Repeated)
terminal   = quotedString.setParseAction(Terminal)
term       = (keyword | terminal | optional | repeated | (LPAREN + expression + RPAREN)).setParseAction(Term)
concat     = Group(term + OneOrMore(term)).setParseAction(Concat)
factor     = concat | term
union      = Group(factor + OneOrMore(VBAR + factor)).setParseAction(Union)
rule       = identifier + EQUALS + expression + PERIOD

expression << (union | factor)

grammar = OneOrMore(Group(rule))
grammar.ignore(HASH + restOfLine)

express = grammar.parseFile(sys.argv[1])

def find_bytype(expr, ty, li = None):
    if li is None: li = []
    if isinstance(expr, Term):
        expr = expr.contents
    if isinstance(expr, ty):
        li.append(expr)
        return set(li)
    elif isinstance(expr, Expression):
        for term in expr:
            find_bytype(term, ty, li)
    return set(li)

actions = {
    'type_decl'                 : "TypeDeclaration",
    'entity_decl'               : "EntityDeclaration",
    'enumeration_type'          : "EnumerationType",
    'aggregation_types'         : "AggregationType",
    'general_aggregation_types' : "AggregationType",
    'select_type'               : "SelectType",
    'binary_type'               : "BinaryType",
    'subtype_declaration'       : "SubTypeExpression",
    'supertype_constraint'      : "SuperTypeExpression",
    'derive_clause'             : "AttributeList",
    'inverse_clause'            : "AttributeList",
    'inverse_attr'              : "InverseAttribute",
    'bound_spec'                : "BoundSpecification",
    'explicit_attr'             : "ExplicitAttribute",
    'width_spec'                : "WidthSpec",
    'string_type'               : "StringType",
    'named_types'               : "NamedType",
    'simple_types'              : "SimpleType",
}

to_emit = set(id for id, expr in express)
emitted = set()
to_combine = set(["simple_id"])
statements = []
    
terminals = reduce(lambda x,y: x | y, (find_bytype(e, Terminal) for id, e in express))
keywords = list(filter(operator.attrgetter('is_keyword'), terminals))
negated_keywords = map(lambda s: "~%s" % s, keywords)
no_action = {"letter", "digit", "digits", "real_literal", "integer_literal"}

while True:
    emitted_in_loop = set()
    for id, expr in express:
        kws = map(repr, find_bytype(expr, Keyword))
        found = [k in emitted for k in kws]
        if id in to_emit and all(found):
            emitted_in_loop.add(id)
            emitted.add(id)
            stmt = "(%s)" % expr
            if id in to_combine:
                stmt = " + ".join(itertools.chain(negated_keywords, ("originalTextFor(Combine%s)" % stmt,)))
            if id not in no_action and not isinstance(expr.contents, Keyword) and not id in to_combine:
                node_type = "ListNode" if "ZeroOrMore" in stmt else "Node"
                action = actions.get(id, "lambda s, loc, t: %s(s, loc, t, rule=\"%s\")" % (node_type, id))
                stmt = "%s.setParseAction(%s)" % (stmt, action)
            statements.append("%s = %s(\"%s\")" % (id, stmt, id))
    to_emit -= emitted_in_loop
    if not emitted_in_loop: break

for id in to_emit:
    statements.append("%s = Forward()(\"%s\")" % (id, id))

for id in to_emit:
    expr = [e for k, e in express if k == id][0]
    stmt = "(%s)" % expr
    if id in to_combine:
        stmt = "Suppress%s" % stmt
    if id not in no_action and not isinstance(expr.contents, Keyword):
        node_type = "ListNode" if "ZeroOrMore" in stmt else "Node"
        action = ".setParseAction(%s)" % (actions[id] if id in actions else "lambda s, loc, t: %s(s, loc, t, rule=\"%s\")" % (node_type, id))
        stmt = "(%s)%s" % (stmt, action)
    statements.append("%s << %s" % (id, stmt))

print ("""
# This file is generated by IfcOpenShell ifcexpressparser bootstrap.py

import os
import sys
import pickle

import schema
import mapping

from pyparsing import *
from nodes import *

def parse(fn):
    cache_file = fn + ".cache.dat"
    if os.path.exists(cache_file):
        with open(cache_file, "rb") as f:
            m = pickle.load(f)
    else:      
        %s

        syntax.ignore("--" + restOfLine)
        syntax.ignore(Regex(r"\((?:\*(?:[^*]*\*+)+?\))"))
        ast = syntax.parseFile(fn)
        s = schema.Schema(ast)
        m = mapping.Mapping(s)

        with open(cache_file, "wb") as f:
            pickle.dump(m, f, protocol=0)
    return m
            
if __name__ == "__main__":
    m = parse(sys.argv[1])
    import importlib
    for output in sys.argv[2:]:
        mdl = importlib.import_module(output)
        mdl.Generator(m).emit()
    sys.stdout.write(m.schema.name)
"""%('\n        '.join(statements)))