#!/usr/bin/env python3

import argparse
import logging
import re
from pathlib import Path

IN_ROOTS = [
    Path.cwd().joinpath(s).resolve(strict=True)
    for s in [
        "src",
        "src/Runtime",
        "src/MSL",
        "src/melee",
        "src/melee/ft/kinds",
        "libs/doldecomp/include",
        "libs/dolphin/include",
        "libs/dolphin/src",
        "build/GALE01/include",
    ]
]

OUT_ROOTS = [
    IN_ROOTS[2],  # src/MSL
    IN_ROOTS[0],  # src
    IN_ROOTS[5],  # libs/dolphin/include
    IN_ROOTS[7],  # build/GALE01/include
]

INCLUDE_RE = re.compile(
    r'^#include [<"](?P<path>.*?)[>"](?P<remaining>.*)$', re.MULTILINE
)
DEFAULT_FMT = "#include <{}>"


def parse_args() -> list[Path]:
    parser = argparse.ArgumentParser(
        description="Rewrite #include paths in selected C/H files."
    )
    parser.add_argument(
        "paths",
        nargs="+",
        type=Path,
        help="One or more existing .c/.h files under an IN_ROOT.",
    )
    args = parser.parse_args()

    files: list[Path] = []
    for raw_path in args.paths:
        try:
            path = raw_path.resolve(strict=True)
        except FileNotFoundError:
            parser.error(f"path does not exist: {raw_path}")

        if not any(path.is_relative_to(root) for root in IN_ROOTS):
            parser.error(f"path is not under any IN_ROOT: {raw_path}")

        if not path.is_file() or not path.match("*.[ch]"):
            parser.error(f"path does not match *.[ch]: {raw_path}")

        files.append(path)

    # Avoid processing the same file twice if it was supplied more than once.
    return list(dict.fromkeys(files))


def rewrite_file(src_path: Path) -> None:
    logging.debug("Opening `%s`", src_path)
    text = src_path.read_text(encoding="utf-8", errors="strict", newline="")
    local_root = src_path.parent.resolve(strict=True)
    in_roots = [local_root, *IN_ROOTS]
    out_roots = [*OUT_ROOTS]

    def repl(m: re.Match[str]) -> str:
        mp = Path(m["path"])
        s = m[0]
        logging.debug("Evaluating `%s`", s)

        def put(p: Path) -> str:
            p = p.resolve()

            def decide_fmt() -> tuple[Path, str]:
                if p.suffix not in {".c", ".h", ".inc"}:
                    logging.warning("Deleting suspicious include `%s`", m[0])
                    return p, ""

                if src_path.suffix == ".c":
                    try:
                        return p.relative_to(src_path.parent), '#include "{}"{}'
                    except ValueError:
                        pass

                for root in out_roots:
                    try:
                        return p.relative_to(root), "#include <{}>{}"
                    except ValueError:
                        continue
                logging.error("Out root not found: %s", mp)
                return p, m[0]

            p, fmt = decide_fmt()
            s = fmt.format(p.as_posix(), m["remaining"])
            logging.info("Replaced `%s`", s)
            return s

        def search_relative() -> str | None:
            if src_path.suffix == ".c" and mp.is_relative_to(src_path.parent):
                logging.info(
                    "Relative include: `%s`", p := mp.relative_to(src_path.parent)
                )
                return put(p)
            return None

        def search_sus() -> str | None:
            if mp.suffix not in {".c", ".h", ".inc"}:
                return put(mp)
            return None

        def search_roots() -> str | None:
            for root in in_roots:
                logging.debug("Trying `%s` / `%s`", root, str(mp))
                try:
                    resolved = root.joinpath(mp).resolve(strict=True)
                    logging.info("Found `%s`", resolved)
                    return put(resolved)
                except FileNotFoundError:
                    logging.debug("Did not find `%s` in `%s`", mp, root)
                    continue
            return None

        s = next(
            filter(
                lambda x: x is not None,
                map(
                    lambda f: f(),
                    [
                        search_relative,
                        search_sus,
                        search_roots,
                    ],
                ),
            ),
            None,
        )
        if s is None:
            logging.error("Didn't find `%s`", s := m[0])

        return s

    _ = src_path.write_text(
        INCLUDE_RE.sub(repl, text), encoding="utf-8", errors="strict", newline=""
    )


def main() -> None:
    logging.basicConfig(level=logging.WARNING)
    for src_path in parse_args():
        rewrite_file(src_path)


if __name__ == "__main__":
    main()