#!/usr/bin/env python3
"""Patch Steam localconfig.vdf LaunchOptions for Devour (1274570).

Sets WINEDLLOVERRIDES="version=n,b" %command% inside every userdata/*/config/
localconfig.vdf Apps->1274570 block. Must be run while Steam is CLOSED — Steam
rewrites localconfig.vdf from memory on exit and discards external edits.

VDF escaping note: quotes inside values are a single backslash + quote (\").
Getting that through bash heredocs is what broke account 919954036 before
(it ended up as \\\"). This module builds bytes explicitly via chr(92).
"""
import pathlib, sys

APPID = "1274570"
BQ = chr(92) + '"'  # backslash + quote
TARGET_LINE = (
    "\t" * 6 + '"LaunchOptions"' + "\t\t"
    + '"WINEDLLOVERRIDES=' + BQ + 'version=n,b' + BQ + ' %command%"' + "\n"
)

def patch(path: pathlib.Path) -> bool:
    lines = path.read_text(errors="ignore").splitlines(True)
    changed = False
    i = 0
    while i < len(lines) - 1:
        if (
            lines[i].strip() == f'"{APPID}"'
            and lines[i].startswith("\t" * 5)
            and lines[i + 1].strip() == "{"
            and lines[i + 1].startswith("\t" * 5)
        ):
            depth = 1
            j = i + 2
            lo_i = None
            end = None
            while j < len(lines):
                s = lines[j].strip()
                if s == "{":
                    depth += 1
                elif s == "}":
                    depth -= 1
                    if depth == 0:
                        end = j
                        break
                if s.startswith('"LaunchOptions"') and lines[j].startswith("\t" * 6):
                    lo_i = j
                j += 1
            if end is None:
                i = j + 1
                continue
            if lo_i is None:
                lines.insert(end, TARGET_LINE)
                print(f"{path.parent.parent.name}: inserted LaunchOptions")
                changed = True
            elif lines[lo_i] != TARGET_LINE:
                print(f"{path.parent.parent.name}: fixed {lines[lo_i].strip()[:70]!r}")
                lines[lo_i] = TARGET_LINE
                changed = True
            else:
                print(f"{path.parent.parent.name}: already exact")
            i = end + 1
            continue
        i += 1
    if changed:
        bak = path.with_suffix(".vdf.bak.devour")
        bak.write_text("".join(lines))
        path.write_text("".join(lines))
    return changed

if __name__ == "__main__":
    paths = [pathlib.Path(a) for a in sys.argv[1:]] or list(
        pathlib.Path.home().glob(".local/share/Steam/userdata/*/config/localconfig.vdf")
    )
    for p in paths:
        if p.exists():
            patch(p)