"""Verifies the Spearfoot tunables (block_size, block_buffer, passes)
actually thread through to the badblocks command line.

These three settings are exposed in Settings → Burn-in. Without a test,
nothing catches if a future refactor drops one of the flags or reads
from the wrong attribute. The defaults match the Spearfoot disk-burnin.sh
community script; non-defaults can roughly halve runtime on multi-TB
drives at the cost of more RAM.

Run inside the container image so app deps are present.
"""

from __future__ import annotations

import unittest

from app.burnin.stages import _build_badblocks_cmd
from app.config import settings


class TestBadblocksCmd(unittest.TestCase):

    def setUp(self):
        # Snapshot defaults so each test can mutate freely without
        # polluting siblings or the running process.
        self._snap = (
            settings.surface_validate_block_size,
            settings.surface_validate_block_buffer,
            settings.surface_validate_passes,
        )

    def tearDown(self):
        (
            settings.surface_validate_block_size,
            settings.surface_validate_block_buffer,
            settings.surface_validate_passes,
        ) = self._snap

    def test_defaults_match_spearfoot(self):
        """Out of the box: -b 4096 -c 64 -p 1 — matches the
        disk-burnin.sh community script's recommendation for HDDs."""
        cmd = _build_badblocks_cmd("sda")
        self.assertIn("-b 4096", cmd)
        self.assertIn("-c 64", cmd)
        self.assertIn("-p 1", cmd)
        self.assertIn("/dev/sda", cmd)
        # Destructive write+verify mode must always be present — anything
        # else (read-only, non-destructive) defeats the purpose of burn-in.
        self.assertIn("-wsv", cmd)

    def test_tunables_propagate_to_cmd(self):
        """Operator-set values (e.g. for paranoid 3-pass burn-in on a
        suspect drive, or 8 KiB blocks for faster scan on a 24 TB HDD)
        must end up in the shell command."""
        settings.surface_validate_block_size = 8192
        settings.surface_validate_block_buffer = 128
        settings.surface_validate_passes = 3
        cmd = _build_badblocks_cmd("sdb")
        self.assertIn("-b 8192", cmd)
        self.assertIn("-c 128", cmd)
        self.assertIn("-p 3", cmd)
        self.assertNotIn("-b 4096", cmd)  # no leak from defaults
        self.assertNotIn("-c 64", cmd)
        self.assertIn("/dev/sdb", cmd)

    def test_pid_capture_wrapper_intact(self):
        """The `sh -c 'echo PID:$$; exec ...'` wrapper is what makes
        out-of-band kill -9 work over a fresh SSH session — asyncssh's
        signal channel is silently ignored by sshd. If a future refactor
        drops the wrapper, a cancel won't actually stop the test."""
        cmd = _build_badblocks_cmd("sda")
        self.assertTrue(cmd.startswith("sh -c 'echo PID:$$; exec badblocks"))
        self.assertTrue(cmd.endswith("'"))


if __name__ == "__main__":
    unittest.main()