"""Installer acceptance under the service account; never opens a USB device."""
import hashlib
import json
import os
from pathlib import Path
import subprocess
import tempfile


def check(root):
    manifest = json.loads((root / "manifest.json").read_text())
    for name, expected in manifest["files"].items():
        path = root / name
        if path.is_symlink() or not path.resolve().is_relative_to(root.resolve()):
            raise RuntimeError("Untrusted native runtime path")
        if path.stat().st_size != expected["bytes"] or hashlib.sha256(path.read_bytes()).hexdigest() != expected["sha256"]:
            raise RuntimeError("Native runtime integrity check failed")
    with tempfile.TemporaryDirectory(prefix="mission-core-vesc-check-") as temporary:
        env = {"PATH":"/usr/bin:/bin", "LANG":"C.UTF-8", "QT_QPA_PLATFORM":"offscreen",
               "LD_LIBRARY_PATH":str(root / "lib"), "QT_PLUGIN_PATH":str(root / "plugins"),
               "XDG_CONFIG_HOME":temporary, "XDG_CACHE_HOME":temporary}
        result = subprocess.run([str(root / "bin/mission-core-vesc-engine"), "--offline"],
            env=env, input=b'{"id":1,"method":"engine"}\n', capture_output=True, timeout=15, check=True)
        replies = [json.loads(line) for line in result.stdout.splitlines()]
        if (len(replies) != 2 or not replies[0]["ready"] or not replies[1]["ok"]
                or replies[1]["result"]["hardware_enabled"] or replies[1]["result"]["connected"]
                or replies[1]["result"]["commit"] != manifest["upstream_commit"]):
            raise RuntimeError("Native engine offline check failed")
    print(json.dumps({"ok":True, "upstream_commit":manifest["upstream_commit"], "hardware_access":False}))


if __name__ == "__main__":
    if os.geteuid() == 0: raise RuntimeError("Run as the VESC service account")
    check(Path(__file__).resolve().parent / "native")