"""Shared simavr harness for the pureboot tests: spawn the device runner,
hand out its pty, restart it from a flash dump (the power-fail path), and
keep its chatter out of undrained pipes."""

import os
import signal
import subprocess


class Device:
    def __init__(self, binary, elf, mcu, hz, base_hex, page, baud, dump, reset_hex=None, resume=None):
        cmd = [binary, elf, mcu, hz, base_hex, str(page), str(baud), dump]
        if reset_hex is not None or resume is not None:
            # Chips without a hardware boot section — the tinies and the
            # m48s — reset to address 0 like silicon; the boot-sectioned
            # megas re-vector to the loader base (BOOTRST).
            patch = not mcu.startswith("atmega") or mcu.startswith("atmega48")
            cmd.append(reset_hex if reset_hex is not None else ("0" if patch else base_hex))
        if resume is not None:
            cmd.append(resume)
        self.log = open(dump + ".log", "a")
        self.proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=self.log, text=True)
        self.dump = dump
        self.pty = None
        for _ in range(50):
            line = self.proc.stdout.readline()
            if not line:
                break
            if line.startswith("PB_PTY"):
                self.pty = line.split()[1]
                break
        if not self.pty:
            self.stop()
            raise RuntimeError("device did not report a pty")

    def reset(self):
        """The external reset line: SIGUSR1 re-enters at the reset vector."""
        self.proc.send_signal(signal.SIGUSR1)

    def power_fail(self):
        """SIGTERM: the runner dumps its flash and exits — the image a
        restart resumes from."""
        self.stop()
        return self.dump

    def stop(self):
        self.proc.terminate()
        try:
            self.proc.wait(timeout=5)
        except subprocess.TimeoutExpired:
            self.proc.kill()
        self.log.close()


def run_tool(tool, pty, baud, *args, timeout=180):
    result = subprocess.run(
        [os.environ.get("PYTHON", "python3"), tool, "--port", pty, "--baud", str(baud), "--wait", "25", *args],
        capture_output=True,
        text=True,
        timeout=timeout,
    )
    print(result.stdout, end="")
    if result.returncode != 0:
        raise RuntimeError(f"tool exited {result.returncode}: {result.stderr.strip()}")
    return result.stdout