#!/usr/bin/env python3
# To run from vim add to your .vimrc something similar to:
# command -nargs=* Rpcgen :r !/home/mislav/code/memgraph/tools/rpcgen <args>


import sys

USAGE = "\n\nUsage:\n" \
        "./rpcgen request_response_name request_args -- response_args\n" \
        "Arguments should be seperated with minus sign (-).\n" \
        "Example: ./rpcgen Sum int x - int y -- int sum\n\n"

assert len(sys.argv) >= 3, "Too few arguments.\n" + USAGE

request_response_name = sys.argv[1]
args_string = " ".join(sys.argv[2:])
split = args_string.split("--")
assert len(split) == 2, "Arguments should contain one -- separator.\n" + USAGE
request_args, response_args = split

def generate(message_name, args):
    def process_arg(arg):
        arg = arg.strip()
        assert arg, "Each arg should be non empty string.\n" + USAGE
        for i in range(len(arg) - 1, -1, -1):
            if not arg[i].isalpha() and arg[i] != "_": break
        assert i != -1 and i != len(arg), "Each string separated with - " \
                "should contain type and variable name.\n" + USAGE
        typ = arg[:i+1].strip()
        name = arg[i+1:].strip()
        return typ, name
    types, names = zip(*map(process_arg, args.split("-")))

    return \
"""
struct {message_name} : public Message {{
  {message_name}() {{}}  // cereal needs this
  {message_name}({constructor_args}): {init_list} {{}}
  {members}

  template <class Archive>
  void serialize(Archive &ar) {{
    ar(cereal::virtual_base_class<Message>(this), {serialize_args});
  }}
}};
CEREAL_REGISTER_TYPE({message_name});""" \
    .format(message_name=message_name,
            constructor_args=",".join(
                map(lambda x: x[0] + " " + x[1], zip(types, names))),
            init_list=", ".join(map(lambda x: "{x}({x})".format(x=x), names)),
            members="\n".join(map(lambda x:
                "{} {};".format(x[0], x[1]), zip(types, names))),
            serialize_args=", ".join(names))

request_name = request_response_name + "Req"
response_name = request_response_name + "Res"
req_class = generate(request_name, request_args)
res_class = generate(response_name, response_args)
print(req_class)
print(res_class)
print("using {} = RequestResponse<{}, {}>;".format(
    request_response_name, request_name, response_name))