# Reverse PCAD-2004 ECO file for unnamed network split
# Converts ECO commands:
#
# NetSplit "NET00351" "NET00362" "T617-3" "T614-2" "T618-2" "T618-1" 
# NetDelete "NET00351"
#
# into NetRename "NET00362" "NET00351" and reverses the order
#
import argparse
import sys
import re
import os

RE_SPLIT  = re.compile(r'NetSplit(\s\"[.\-_~a-zA-Z0-9]*\")(\s\"[.\-_~a-zA-Z0-9]*\").*')
RE_DELETE = re.compile(r'NetDelete(\s\"[.\-_~a-zA-Z0-9]*\")')

def load_eco(name):
        #
        # Add the default file name extension if needed
        #
        if not os.path.splitext(name)[1]:
            name += '.eco'
        try:
            f = open(name, 'r', -1, None, None)
        except OSError as err:
            raise RuntimeError(err)
        ls = f.readlines()      # read lines from input file
        f.close()

        net = None
        for line in ls:
            if line[0] == ';':
                continue
            match = RE_SPLIT.match(line)
            if match is not None:
                net = match.group(1)
                continue
            match = RE_DELETE.match(line)
            if match is not None:
                if match.group(1) != net:
                    print("Non consistent NetDelete: %s" % line)
                    exit(-1)
                continue
            print("Unrecognized ECO action: %s" % line)
            exit(-1)
        return ls

def save_eco(name, ls):
        f = open(name, 'w')
        #
        # Comment the current ECO content
        #
        for line in ls:
            if line[0] != ';':
                line = '; ' + line;
            f.write(line)
        f.write('; *** ECO Reversing script ***\n')
        #
        # reverse line order
        #
        ls.reverse()
        for line in ls:
            if line[0] == ';':
                continue
            match = RE_SPLIT.match(line)
            if match is not None:
                line = "NetRename" + match.group(2) + match.group(1)
                print(line)
                f.write(line + '\n')
        f.close()


def createParser():
    p = argparse.ArgumentParser(
        description='PCAD4 ECO-file reverting script, Version 24.12a, (c) 1801BM1')
    p.add_argument('eco', nargs=1, help='input eco file', metavar='file')
    return p


def main():
    parser = createParser()
    params = parser.parse_args()
    name = params.eco[0]
    if not os.path.splitext(name)[1]:
        name += '.eco'

    ls = load_eco(name)
    save_eco(name, ls)

if __name__ == '__main__':
    main()