"""Packaging acceptance tests — containerized matrix.

Tests the built deb and rpm packages in throwaway per-distro containers,
verifying the dormant-install contract, upgrade semantics, removal mapping,
and migration guard.  This is the single test seam agreed in the release spec.

Requirements:
  - docker (running, current user in docker group)
  - Built packages in dist/ (run `make package` first)
  - No network access required once containers are built
  - No registry or signing key required

Spec: release-packaging.md §§1–9, ADR 0007
"""
import os
import subprocess
import textwrap
from pathlib import Path

import pytest

REPO_ROOT = Path(__file__).resolve().parent.parent
DIST_DIR = REPO_ROOT / "dist"
VERSION_FILE = REPO_ROOT / "pyproject.toml"

# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

def _get_version() -> str:
    """Extract version from pyproject.toml."""
    for line in VERSION_FILE.read_text().splitlines():
        if line.startswith("version"):
            return line.split("=")[1].strip().strip('"')
    raise RuntimeError("Could not determine version from pyproject.toml")


def _docker_available() -> bool:
    """Check if Docker daemon is reachable."""
    try:
        r = subprocess.run(
            ["docker", "info"], capture_output=True, timeout=10
        )
        return r.returncode == 0
    except (FileNotFoundError, subprocess.TimeoutExpired):
        return False


def _container_exec(container: str, cmd: str) -> tuple[int, str]:
    """Execute a command inside a running container."""
    r = subprocess.run(
        ["docker", "exec", container, "sh", "-c", cmd],
        capture_output=True, text=True, timeout=120,
    )
    return r.returncode, r.stdout + r.stderr


def _find_package(fmt: str, distro: str | None = None) -> Path:
    """Locate the built package artifact."""
    version = _get_version()
    if fmt == "deb":
        candidate = DIST_DIR / f"fenris_{version}_amd64.deb"
    elif fmt == "rpm":
        candidate = DIST_DIR / f"fenris-{version}-1.x86_64.rpm"
    else:
        raise ValueError(f"Unknown format: {fmt}")
    if not candidate.exists():
        pytest.skip(f"Package not found: {candidate} — run `make package` first")
    return candidate


# ---------------------------------------------------------------------------
# Matrix definitions
# ---------------------------------------------------------------------------

DEB_TARGETS = [
    ("debian:bookworm", "deb"),
    ("ubuntu:22.04", "deb"),
    ("ubuntu:24.04", "deb"),
]

RPM_TARGETS = [
    ("fedora:40", "rpm"),
]

ALL_TARGETS = DEB_TARGETS + RPM_TARGETS


# ---------------------------------------------------------------------------
# Dockerfile builders
# ---------------------------------------------------------------------------

def _build_deb_dockerfile(image: str, pkg_name: str) -> str:
    """Dockerfile for testing deb installation."""
    return textwrap.dedent(f"""\
        FROM {image}
        RUN apt-get update && apt-get install -y --no-install-recommends \\
            python3 smartmontools systemd systemd-sysv dbus && \\
            rm -rf /var/lib/apt/lists/*
        COPY dist/{pkg_name} /pkg/{pkg_name}
        RUN dpkg -i /pkg/{pkg_name} || apt-get install -f -y
    """)


def _build_rpm_dockerfile(image: str, pkg_name: str) -> str:
    """Dockerfile for testing rpm installation."""
    return textwrap.dedent(f"""\
        FROM {image}
        RUN dnf install -y --setopt=install_weak_deps=False \
            python3 smartmontools systemd dbus && \
            dnf clean all
        COPY dist/{pkg_name} /pkg/{pkg_name}
        RUN rpm -ivh /pkg/{pkg_name}
    """)


# ---------------------------------------------------------------------------
# Fixtures
# ---------------------------------------------------------------------------

@pytest.fixture(scope="module")
def version():
    return _get_version()


@pytest.fixture(scope="module")
def skip_no_docker():
    if not _docker_available():
        pytest.skip("Docker not available")


# ---------------------------------------------------------------------------
# Shared assertion functions
# ---------------------------------------------------------------------------

def _assert_dormant_layout(container: str, fmt: str, version: str) -> None:
    """Assert the dormant-install contract (spec §6, §7)."""
    # Venv directory exists with expected structure
    rc, out = _container_exec(container, "test -d /opt/fenris && echo OK")
    assert "OK" in out, "Bundled venv not found at /opt/fenris"

    # Venv Python binary exists (may not execute if shared libs differ)
    rc, _ = _container_exec(container, "test -f /opt/fenris/bin/python3")
    assert rc == 0, "Venv Python binary not found"

    # Wrapper on PATH
    rc, out = _container_exec(container, "command -v fenris")
    assert rc == 0, f"fenris not on PATH: {out}"

    # Wrapper file exists and is executable
    rc, _ = _container_exec(container, "test -x /usr/bin/fenris")
    assert rc == 0, "Wrapper not found or not executable at /usr/bin/fenris"

    # Wrapper contains the correct version string
    rc, out = _container_exec(container, f"grep -q '{version}' /usr/bin/fenris && echo OK")
    assert "OK" in out, f"Version {version} not found in wrapper script"

    # Helpers in /usr/libexec/fenris
    for helper in ("fenris-monitor", "fenris-collect"):
        rc, _ = _container_exec(container, f"test -x /usr/libexec/fenris/{helper}")
        assert rc == 0, f"{helper} not found or not executable"

    # systemd units in vendor placement
    for unit in ("fenris-collect.timer", "fenris-collect.service"):
        rc, _ = _container_exec(container, f"test -f /usr/lib/systemd/system/{unit}")
        assert rc == 0, f"{unit} not found in vendor placement"

    # Polkit policy
    rc, _ = _container_exec(
        container,
        "test -f /usr/share/polkit-1/actions/com.bongbetic.fenris.monitor.policy",
    )
    assert rc == 0, "Polkit policy not found"

    # sysusers and tmpfiles fragments
    rc, _ = _container_exec(container, "test -f /usr/lib/sysusers.d/fenris.conf")
    assert rc == 0, "sysusers fragment not found"
    rc, _ = _container_exec(container, "test -f /usr/lib/tmpfiles.d/fenris.conf")
    assert rc == 0, "tmpfiles fragment not found"

    # Placeholder-commented config
    rc, out = _container_exec(container, "cat /etc/fenris/fenris.conf")
    assert rc == 0, "fenris.conf not found"
    assert "device" in out.lower() or "devices" in out.lower() or "#" in out, \
        "Config does not appear to be placeholder-commented"

    # fenris group exists
    rc, out = _container_exec(container, "getent group fenris")
    assert rc == 0, "fenris group not created"

    # Observation store directory
    if fmt == "deb":
        rc, out = _container_exec(container, "stat -c '%a %U %G' /var/lib/fenris")
        assert rc == 0, "Observation store directory not created"
        parts = out.strip().split()
        assert parts[0] == "2750", f"Store dir mode: expected 2750, got {parts[0]}"
        assert parts[1] == "root", f"Store dir owner: expected root, got {parts[1]}"
        assert parts[2] == "fenris", f"Store dir group: expected fenris, got {parts[2]}"
    else:
        # rpm: directory owned by package (ghost)
        rc, _ = _container_exec(container, "test -d /var/lib/fenris")
        assert rc == 0, "Observation store directory not found"

    # Timer is disabled and inactive (dormant)
    rc, out = _container_exec(
        container, "systemctl is-enabled fenris-collect.timer 2>/dev/null || echo disabled"
    )
    assert "disabled" in out.lower() or "masked" in out.lower() or rc != 0, \
        f"Timer should be disabled (dormant), got: {out}"

    rc, out = _container_exec(
        container, "systemctl is-active fenris-collect.timer 2>/dev/null || echo inactive"
    )
    assert "inactive" in out.lower() or "dead" in out.lower() or rc != 0, \
        f"Timer should be inactive (dormant), got: {out}"

    # No hand-rolled manifest
    rc, _ = _container_exec(container, "test -f /var/lib/fenris/manifest.txt")
    assert rc != 0, "Legacy manifest.txt should not exist in package install"


def _assert_migration_guard(container: str, fmt: str, pkg_name: str) -> None:
    """Assert that install aborts on make-install remnants (spec §7, §9)."""
    if fmt == "deb":
        # Plant the legacy manifest marker
        _container_exec(container, "mkdir -p /var/lib/fenris")
        _container_exec(container, "echo '# manifest' > /var/lib/fenris/manifest.txt")
        # Attempt install — should fail with migration pointer
        rc, out = _container_exec(
            container,
            f"dpkg -i /pkg/{pkg_name} 2>&1 || true",
        )
        assert "remnants" in out.lower() or "migrat" in out.lower() or rc != 0, \
            f"Migration guard did not trigger: {out}"
        # Clean up marker for subsequent tests
        _container_exec(container, "rm -f /var/lib/fenris/manifest.txt")
    else:
        # Plant the admin unit marker
        _container_exec(container, "mkdir -p /etc/systemd/system")
        _container_exec(
            container,
            "echo '[Unit]' > /etc/systemd/system/fenris-collect.timer",
        )
        rc, out = _container_exec(
            container,
            f"rpm -ivh /pkg/{pkg_name} 2>&1 || true",
        )
        assert "remnants" in out.lower() or "migrat" in out.lower() or rc != 0, \
            f"Migration guard did not trigger: {out}"
        _container_exec(
            container,
            "rm -f /etc/systemd/system/fenris-collect.timer",
        )


def _assert_upgrade_semantics(container: str, fmt: str, pkg_name: str, version: str) -> None:
    """Assert upgrade behavior (spec §7, ADR 0007 §6)."""
    # Create a fake observation store using system Python
    # (venv Python may not execute if host shared libs differ)
    _container_exec(
        container,
        "mkdir -p /var/lib/fenris && "
        "python3 -c \""
        "import sqlite3; "
        "c = sqlite3.connect('/var/lib/fenris/observations.db'); "
        "c.execute('PRAGMA user_version=1'); "
        "c.commit(); c.close()\"",
    )

    if fmt == "deb":
        # Fake older version so dpkg treats reinstall as upgrade
        _container_exec(
            container,
            f"sed -i 's/^Version: {version}$/Version: 0.2.0/' /var/lib/dpkg/status",
        )
        # Re-install triggers upgrade path
        rc, out = _container_exec(
            container,
            f"dpkg --force-confnew -i /pkg/{pkg_name} 2>&1 || "
            "apt-get install -f -y 2>&1 || true",
        )
    else:
        # RPM: manually invoke the post scriptlet with upgrade arguments ($1=2)
        # because faking a different version in the binary RPM database is not
        # practical — we only need to verify the scriptlet's upgrade behaviour.
        _container_exec(
            container,
            f"rpm -q --scripts -p /pkg/{pkg_name} "
            "| sed -n '/^postinstall scriptlet/,/^preuninstall/"
            "{/^preuninstall/d;/^postinstall scriptlet/d;p}' | sh -s 2 2",
        )

    # Snapshot should exist
    rc, _ = _container_exec(
        container, "test -f /var/lib/fenris/observations.db.bak"
    )
    assert rc == 0, "Observation store snapshot not created on upgrade"

    # Original store still exists
    rc, _ = _container_exec(
        container, "test -f /var/lib/fenris/observations.db"
    )
    assert rc == 0, "Observation store missing after upgrade"


def _assert_removal_semantics(container: str, fmt: str) -> None:
    """Assert removal mapping (spec §7)."""
    if fmt == "deb":
        # remove (not purge) — config and store survive
        rc, out = _container_exec(
            container, "dpkg --purge fenris 2>&1 || true"
        )
        # After purge: config gone, store gone (our postrm removes on purge)
        # But the store dir may survive since it's not package-owned
    else:
        # rpm erase
        rc, out = _container_exec(
            container, "rpm -e fenris 2>&1 || true"
        )

    # Units removed
    rc, _ = _container_exec(
        container, "test -f /usr/lib/systemd/system/fenris-collect.timer"
    )
    assert rc != 0, "Timer unit should be removed after uninstall"

    # Helpers removed
    rc, _ = _container_exec(
        container, "test -f /usr/libexec/fenris/fenris-monitor"
    )
    assert rc != 0, "Helper should be removed after uninstall"

    # Venv key files removed (directories may remain if non-empty)
    rc, _ = _container_exec(container, "test -f /opt/fenris/bin/python3")
    assert rc != 0, "Venv Python should be removed after uninstall"


# ---------------------------------------------------------------------------
# Tests — dormant install (tracer bullet)
# ---------------------------------------------------------------------------

@pytest.mark.slow
@pytest.mark.parametrize("image,fmt", ALL_TARGETS, ids=[t[0] for t in ALL_TARGETS])
def test_dormant_install(skip_no_docker, image, fmt, version):
    """Install package in container, assert dormant layout and ownership."""
    pkg = _find_package(fmt)
    pkg_name = pkg.name

    # Copy package to build context
    build_dir = REPO_ROOT / "build" / "test-container"
    build_dir.mkdir(parents=True, exist_ok=True)
    (build_dir / "dist").mkdir(exist_ok=True)
    subprocess.run(
        ["cp", str(pkg), str(build_dir / "dist" / pkg_name)],
        check=True,
    )

    # Write Dockerfile
    if fmt == "deb":
        dockerfile = _build_deb_dockerfile(image, pkg_name)
    else:
        dockerfile = _build_rpm_dockerfile(image, pkg_name)
    (build_dir / "Dockerfile").write_text(dockerfile)

    # Build image
    tag = f"fenris-test-{image.replace(':', '-').replace('/', '-')}"
    subprocess.run(
        ["docker", "build", "-t", tag, str(build_dir)],
        check=True,
        capture_output=True,
        timeout=300,
    )

    # Run container
    container = f"fenris-test-{os.getpid()}"
    subprocess.run(
        [
            "docker", "run", "-d", "--name", container,
            "--tmpfs", "/tmp:exec,size=64m",
            tag, "sleep", "infinity",
        ],
        check=True,
        capture_output=True,
    )

    try:
        _assert_dormant_layout(container, fmt, version)
    finally:
        subprocess.run(
            ["docker", "rm", "-f", container],
            capture_output=True,
        )


# ---------------------------------------------------------------------------
# Tests — migration guard
# ---------------------------------------------------------------------------

@pytest.mark.slow
@pytest.mark.parametrize("image,fmt", ALL_TARGETS, ids=[t[0] for t in ALL_TARGETS])
def test_migration_guard(skip_no_docker, image, fmt, version):
    """Assert install aborts on make-install remnants."""
    pkg = _find_package(fmt)
    pkg_name = pkg.name

    build_dir = REPO_ROOT / "build" / "test-container-guard"
    build_dir.mkdir(parents=True, exist_ok=True)
    (build_dir / "dist").mkdir(exist_ok=True)
    subprocess.run(
        ["cp", str(pkg), str(build_dir / "dist" / pkg_name)],
        check=True,
    )

    # Dockerfile: install with remnants pre-planted
    if fmt == "deb":
        dockerfile = textwrap.dedent(f"""\
            FROM {image}
            RUN apt-get update && apt-get install -y --no-install-recommends \
                python3 python3-minimal smartmontools systemd systemd-sysv dbus && \
                rm -rf /var/lib/apt/lists/*
            COPY dist/{pkg_name} /pkg/{pkg_name}
            # Plant make-install remnant BEFORE installing
            RUN mkdir -p /var/lib/fenris && echo '# manifest' > /var/lib/fenris/manifest.txt
        """)
    else:
        dockerfile = textwrap.dedent(f"""\
            FROM {image}
            RUN dnf install -y --setopt=install_weak_deps=False \
                python3 smartmontools systemd dbus && \
                dnf clean all
            COPY dist/{pkg_name} /pkg/{pkg_name}
            RUN mkdir -p /etc/systemd/system && \\
                echo '[Unit]' > /etc/systemd/system/fenris-collect.timer
        """)
    (build_dir / "Dockerfile").write_text(dockerfile)

    tag = f"fenris-guard-{image.replace(':', '-').replace('/', '-')}"
    subprocess.run(
        ["docker", "build", "-t", tag, str(build_dir)],
        check=True,
        capture_output=True,
        timeout=300,
    )

    container = f"fenris-guard-{os.getpid()}"
    subprocess.run(
        [
            "docker", "run", "-d", "--name", container,
            "--tmpfs", "/tmp:exec,size=64m",
            tag, "sleep", "infinity",
        ],
        check=True,
        capture_output=True,
    )

    try:
        _assert_migration_guard(container, fmt, pkg_name)
    finally:
        subprocess.run(
            ["docker", "rm", "-f", container],
            capture_output=True,
        )


# ---------------------------------------------------------------------------
# Tests — upgrade semantics
# ---------------------------------------------------------------------------

@pytest.mark.slow
@pytest.mark.parametrize("image,fmt", ALL_TARGETS, ids=[t[0] for t in ALL_TARGETS])
def test_upgrade_semantics(skip_no_docker, image, fmt, version):
    """Assert upgrade snapshots store and preserves config."""
    pkg = _find_package(fmt)
    pkg_name = pkg.name

    build_dir = REPO_ROOT / "build" / "test-container-upgrade"
    build_dir.mkdir(parents=True, exist_ok=True)
    (build_dir / "dist").mkdir(exist_ok=True)
    subprocess.run(
        ["cp", str(pkg), str(build_dir / "dist" / pkg_name)],
        check=True,
    )

    if fmt == "deb":
        dockerfile = _build_deb_dockerfile(image, pkg_name)
    else:
        dockerfile = _build_rpm_dockerfile(image, pkg_name)
    (build_dir / "Dockerfile").write_text(dockerfile)

    tag = f"fenris-upgrade-{image.replace(':', '-').replace('/', '-')}"
    subprocess.run(
        ["docker", "build", "-t", tag, str(build_dir)],
        check=True,
        capture_output=True,
        timeout=300,
    )

    container = f"fenris-upgrade-{os.getpid()}"
    subprocess.run(
        [
            "docker", "run", "-d", "--name", container,
            "--tmpfs", "/tmp:exec,size=64m",
            tag, "sleep", "infinity",
        ],
        check=True,
        capture_output=True,
    )

    try:
        _assert_upgrade_semantics(container, fmt, pkg_name, version)
    finally:
        subprocess.run(
            ["docker", "rm", "-f", container],
            capture_output=True,
        )


# ---------------------------------------------------------------------------
# Tests — removal semantics
# ---------------------------------------------------------------------------

@pytest.mark.slow
@pytest.mark.parametrize("image,fmt", ALL_TARGETS, ids=[t[0] for t in ALL_TARGETS])
def test_removal_semantics(skip_no_docker, image, fmt, version):
    """Assert removal cleans package-owned files."""
    pkg = _find_package(fmt)
    pkg_name = pkg.name

    build_dir = REPO_ROOT / "build" / "test-container-removal"
    build_dir.mkdir(parents=True, exist_ok=True)
    (build_dir / "dist").mkdir(exist_ok=True)
    subprocess.run(
        ["cp", str(pkg), str(build_dir / "dist" / pkg_name)],
        check=True,
    )

    if fmt == "deb":
        dockerfile = _build_deb_dockerfile(image, pkg_name)
    else:
        dockerfile = _build_rpm_dockerfile(image, pkg_name)
    (build_dir / "Dockerfile").write_text(dockerfile)

    tag = f"fenris-removal-{image.replace(':', '-').replace('/', '-')}"
    subprocess.run(
        ["docker", "build", "-t", tag, str(build_dir)],
        check=True,
        capture_output=True,
        timeout=300,
    )

    container = f"fenris-removal-{os.getpid()}"
    subprocess.run(
        [
            "docker", "run", "-d", "--name", container,
            "--tmpfs", "/tmp:exec,size=64m",
            tag, "sleep", "infinity",
        ],
        check=True,
        capture_output=True,
    )

    try:
        _assert_removal_semantics(container, fmt)
    finally:
        subprocess.run(
            ["docker", "rm", "-f", container],
            capture_output=True,
        )