import os, sys

import argparse

parser = argparse.ArgumentParser()
parser.add_argument("term_file", help="name of file containing postprocessing term spec")
parser.add_argument("-b", "--build-info", action="store_true", help="print build_info instead of code")
parser.add_argument("-p", "--print_report", action="store_true", help="print code generation report instead of code")
args = parser.parse_args()

from lark import Lark, Visitor, Transformer, v_args, Token

from post import *

from resources.m_template import mod_form

calc_grammar = """
    ?varlist: "[" [NAME ("," NAME)*] "]"

    ?start: statement*

    ?statement: NAME "=" sum -> assign_var
              | avg "{" [NAME ("," NAME)*] "}" -> assign_avg_var
              | varlist

    ?sum: product
        | sum "+" product   -> add
        | sum "-" product   -> sub

    ?product: atom
        | product "*" atom  -> mul
        | product "/" atom  -> div

    ?atom: NUMBER           -> number
         | "-" atom         -> neg
         | NAME             -> var
         | NAME "'"         -> fluc
         | "$" NAME         -> env
         | "(" sum ")"
         | inlinefunc "(" sum ")" -> icall
         | mathfunc "(" sum ("," sum)* ")" -> fcall
         | derivative "(" NAME ")" -> dnx

    avg: "avg" [NAME]

    ?inlinefunc: "sqr" -> sqr
               | "pow3" -> pow3

    ?mathfunc: "log" -> log
             | "exp" -> exp
             | "sqrt" -> sqrt
             | "abs" -> abs
             | "rxn_rate" -> rxn_rate
             | "$" NAME   -> udf

    ?derivative: "ddx"  -> ddx
               | "d2dx" -> d2dx
               | "ddy" -> ddy
               | "d2dy" -> d2dy
               | "ddz" -> ddz
               | "d2dz" -> d2dz

    %import common.CNAME -> NAME
    %import common.NUMBER
    %import common.WS

    COMMENT: /#.*/

    %ignore COMMENT
    %ignore WS
"""


class VersionInfo(object):

    def __init__ (self, input_raw):
        import os, datetime
        import subprocess as sp

        bd = 'build date: {}'
        bb = 'build base: {}'

        self.build_date = bd.format(datetime.datetime.today().ctime())

        try:
            self.build_base = bb.format(sp.check_output(["git", "rev-parse", "HEAD"]).strip())
        except sp.CalledProcessError:
            self.build_base = "None"

        try:
            sp.check_output("git diff --exit-code".split())
            sp.check_output("git diff --cached --exit-code".split())
            self.off_base = ""
        except sp.CalledProcessError:
            self.off_base = "built with changes not commited"

        tinfo = '''
================================================================================
************************************ terms *************************************
--------------------------------------------------------------------------------
{}
================================================================================
'''

        self.term_info = tinfo.format(input_raw)

    def fparams (self):
        return "\n".join([self.build_date, self.build_base, self.off_base, self.term_info])



def test(terms_raw, report=False):

    tree = Lark(calc_grammar, parser='lalr' ).parse(terms_raw)

    ir1 = Stage1(tree)

    ir2 = Stage2(ir1)

    ir3 = Stage3(ir2)

    ir4 = Stage4(ir3)

    cdict = ir4.print_program()

    if not report:
        print mod_form.format( cdict )
    else:
        ir4.save_ir()



def build_info(terms_raw):

    vinfo = VersionInfo(terms_raw)

    print vinfo.fparams()



if __name__ == '__main__':

    with open(args.term_file) as inputfile:
        terms_raw = ((inputfile.read()))

    if args.build_info:
        build_info(terms_raw)
    else:
        test(terms_raw, args.print_report)