import argparse
parser = argparse.ArgumentParser(description="Prints to stdout the patched document")
parser.add_argument('original', help='original document')
parser.add_argument('patch', help='patch file')
args = parser.parse_args()

fa = open(args.original,'r')
la = fa.read().split('\n')
# a workspace for us to edit, each element being a list that 1) originally contains a corresponding line
# in a, 2) may be emptied if that line is removed, 3) may be where we insert new content
ws = [[l] for l in la]
fp = open(args.patch,'r')
lp = fp.read().split('\n')

def str2intv(s):
    if "," in s:
        x, y = s.split(',')
    else:
        x, y = s, s
    return int(x)-1, int(y)

def ws_rm(desc, lp, nb):
    l,r = str2intv(desc)
    for p in range(l,r):
        nb += 1
        assert lp[nb][:2] == "< "
        assert ws[p][0] == lp[nb][2:],\
            f"Patch file wants to delete '{lp[nb][2:]}', but originally line {p} is '{ws[p][0]}'"
        ws[p] = list()
    return nb + 1, l

def ws_insert(p, desc, lp, nb):
    l,r = str2intv(desc)
    for _ in range(l,r):
        nb += 1
        assert lp[nb][:2] == "> "
        ws[p].append(lp[nb][2:])
    return nb + 1

nb = 0
while nb < len(lp):
    line = lp[nb]
    if line:
        assert line[0] != '<' and line[0] != '>', f"Expected description at line {nb}, but got {line}"
    else:
        nb += 1
        continue
    idx_d = line.find('d')
    if idx_d != -1:
        nb, _ = ws_rm(line[:idx_d], lp, nb)
        continue
    idx_a = line.find('a')
    if idx_a != -1:
        p = int(line[:idx_a]) - 1
        nb = ws_insert(p, line[idx_a+1:], lp, nb)
        continue
    idx_c = line.find('c')
    if idx_c != -1:
        nb, p = ws_rm(line[:idx_c], lp, nb)
        nb = ws_insert(p, line[idx_c+1:], lp, nb)
        continue
    assert False, f"Unreachable. Cannot parse line {nb}: {line}"

flatws = [line for _ in ws for line in _]
print('\n'.join(flatws), end="") # Don't want to print additional new line