#!/usr/bin/env python3

import argparse
import os
import sys
import subprocess
import tempfile
from pathlib import Path

script_dir = Path(os.path.dirname(os.path.realpath(__file__)))
root_dir = script_dir / ".."
src_dir = root_dir / "src"

# Project-specific
CPP_FLAGS = [
    "-Iinclude",
    "-Iinclude/libc",
    "-Isrc",
    "-Ibuild/n64-us",
    "-I.",
    "-Iextracted/n64-us",

    "-DF3DEX_GBI_2",
    "-DF3DEX_GBI_PL",
    "-DGBI_DOWHILE",
    "-D__sgi",
    "-D_LANGUAGE_C",
    "-DNON_MATCHING",
    "-D_Static_assert(x, y)=",
    "-D__attribute__(x)=",
    "-D_MIPS_SZLONG=32",
    "-ffreestanding",
    "-DM2CTX",

    "-std=gnu89",
]

# Read through the processes context and replace whatever
def custom_replacements(output):
    actorList = []
    output = output.splitlines()

    i = 0
    while i < len(output):
        line = output[i]

        ############### actorLists[2].first -> Player* ###############
        if "typedef struct ActorListEntry " in line:
            actorListText = ""
            i += 1
            while not output[i].startswith("}"):
                actorListText += output[i]
                i += 1
            actorCats = [
                "actorSwitch",
                "bg",
                "player",
                "explosive",
                "npc",
                "enemy",
                "prop",
                "itemAction",
                "misc",
                "boss",
                "door",
                "chest",
            ]
            for x in range(12):
                actorList.append(actorListText.replace("first;", f"{actorCats[x]};") + "\n")
                if x == 2:
                    actorList[x] = actorList[x].replace("Actor*", "struct Player*")
        elif "ActorListEntry actorLists[ACTORCAT_MAX];" in line:
            output[i] = "struct {\n" + "".join(actorList) + "};"
        ########################################################

        i += 1
    return "\n".join(output)

def import_c_file(in_file) -> str:
    in_file = os.path.relpath(in_file, root_dir)

    cpp_command = ["gcc", "-E", "-P", "-undef", "-dM", *CPP_FLAGS, in_file]
    cpp_command2 = ["gcc", "-E", "-P", "-undef", *CPP_FLAGS, in_file]

    with tempfile.NamedTemporaryFile(suffix=".c") as tmp:
        stock_macros = subprocess.check_output(["gcc", "-E", "-P", "-undef", "-dM", tmp.name], cwd=root_dir, encoding="utf-8")

    out_text = ""
    try:
        out_text += subprocess.check_output(cpp_command, cwd=root_dir, encoding="utf-8")
        out_text += subprocess.check_output(cpp_command2, cwd=root_dir, encoding="utf-8")
    except subprocess.CalledProcessError:
        print(
            "Failed to preprocess input file, when running command:\n"
            + " ".join(cpp_command),
            file=sys.stderr,
            )
        sys.exit(1)

    if not out_text:
        print("Output is empty - aborting")
        sys.exit(1)

    for line in stock_macros.strip().splitlines():
        out_text = out_text.replace(line + "\n", "")
    return out_text


def main():
    parser = argparse.ArgumentParser(usage="./m2ctx.py path/to/file.c or ./m2ctx.py (from an actor or gamestate's asm dir)",
                                     description="Creates a ctx.c file for m2c or decomp.me. "
                                     "Output will be saved as ctx.c")
    parser.add_argument('filepath', help="path of c file to be processed")
    parser.add_argument("--custom", "-c", dest="custom", action="store_true", default=False,
                        help="Apply custom replacements to the output to help aid m2c output")
    args = parser.parse_args()

    c_file_path = args.filepath
    print("Using file: {}".format(c_file_path))

    output = import_c_file(c_file_path)

    if args.custom:
        output = custom_replacements(output)

    ctxPath = root_dir / "ctx.c"
    with ctxPath.open("w", encoding="UTF-8") as f:
        f.write(output)


if __name__ == "__main__":
    main()
