#!/usr/bin/env python3
"""Check the deployment artefacts in ``deploy/`` and the CI workflows — statically, and with reasons.

There is no container runtime and no cluster in the environment this repository is built in
(``which docker podman buildah`` finds nothing; there is no ``kubectl``). That is a fact about the
build environment, not about the artefacts, and the two ways of handling it are both bad: shipping
unchecked manifests and hoping, or shipping none and calling the deployment story "out of scope".

This tool takes the third way. It cannot run a container, so it does not claim to; what it *can* do
is read every document, render the Helm chart with its declared values, and assert the invariants
that this project actually cares about — the ones whose violation is a defect regardless of which
cluster it lands on:

* every document parses, and the chart renders under its own declared defaults;
* every ``.Values`` reference is declared, and every declared value is used (an interface that
  drifts from its implementation is worse than no interface);
* the pod is non-root, cannot escalate, drops all capabilities, and runs a read-only root
  filesystem with an explicit writable ``/tmp`` and evidence volume;
* every container that can be probed declares the port the probe uses — a probe on a stale port is
  a Deployment that never becomes Ready;
* requests and limits exist, images are pinned (no ``:latest``), and there is no ``hostPath``, no
  host namespace, and no ``privileged: true``;
* the policy embedded in each ConfigMap is parsed by the *project's own* policy loader, so a
  manifest cannot ship a policy that Docket would refuse to read;
* the compose file's verifier waits for the run to finish and mounts evidence read-only;
* the CI workflows parse and have jobs with steps (a workflow with a YAML error runs nothing,
  which looks like a green build from the outside);
* every path referenced from these artefacts exists.

The load-bearing test of this tool is not that it passes on this repository — it is that it **fails
on a broken artefact**. ``tests/test_deploy_check.py`` breaks each invariant on purpose, one
fixture per check, and asserts the tool notices; a checker that cannot fail is decoration.

Exit codes: ``0`` all checks passed, ``1`` at least one failed, ``2`` the check could not run
(missing dependency, unreadable tree). A check never reports success for work it did not do — an
absent PyYAML is a ``2`` with the reason on stderr, never a silent pass, and
``tests/test_deploy_check.py`` skips with that same reason instead of failing, so a bare clone's
suite is green-with-skips rather than red.
"""

from __future__ import annotations

import argparse
import json
import re
import sys
import tomllib
from collections.abc import Iterator
from dataclasses import dataclass, field
from pathlib import Path
from typing import Any

#: The repository this tool lives in. `--root` re-points the checker at a copy, which is how its
#: own tests prove it fails on a broken artefact: copy the tree, break one thing, assert the check
#: notices. The policy loader is always imported from *this* checkout, because a copied tree in a
#: test is not a second Docket installation.
HERE = Path(__file__).resolve().parents[1]
ROOT = HERE
DEPLOY = ROOT / "deploy"


def set_root(path: Path | str) -> None:
    """Point the checks at another tree (used by `--root` and by the tests)."""
    global ROOT, DEPLOY  # noqa: PLW0603 - a module-level option, set once per process
    ROOT = Path(path).resolve()
    DEPLOY = ROOT / "deploy"


#: The Helm constructs the renderer implements. Anything outside this set is a *failure*, not a
#: skipped file: a checker that quietly ignores the template it does not understand reports a green
#: tick for an artefact it never looked at.
SUPPORTED_TEMPLATE_DOC = (
    "{{ .Values.a.b }}, {{ .Values.a.b | quote }}, {{ .Values.a.b | int64 }}, {{ . }} and "
    "{{ .field }} inside a range, {{ if .Values.x }}/{{ if not .Values.x }}, {{ else }}, "
    "{{ range .Values.list }}, {{ end }}, and the {{- -}} trim markers"
)

#: The pipes this checker implements. `quote` is Helm's, `int64` is sprig's — and `int64` is the one
#: a chart needs: Helm hands templates a `float64` for every number in `values.yaml`, so a large
#: integer pasted straight into a document renders as `6.7108864e+07` unless a template says what
#: type it means. Refusing an unimplemented pipe by name (rather than passing the text through) is
#: what keeps that honest.
SUPPORTED_PIPES = {"quote", "int64"}

VALUES_REF = re.compile(r"\.Values\.([A-Za-z_][A-Za-z0-9_]*(?:\.[A-Za-z_][A-Za-z0-9_]*)*)")
#: A bare substitution: a `.Values` path, `.` or a field of the ranged item, optionally quoted.
EXPRESSION_OK = re.compile(r"^\.(?:Values\.)?[A-Za-z_][A-Za-z0-9_.]*$|^\.$")
TOKEN = re.compile(r"\{\{(-?)(.*?)(-?)\}\}", re.S)

LATEST_TAGS = {"latest", ""}


class DeployCheckError(Exception):
    """A malformed artefact, or a template construct this tool refuses to guess at."""


# --------------------------------------------------------------------------- #
# A declared subset of the Helm template language
# --------------------------------------------------------------------------- #


@dataclass
class Text:
    value: str


@dataclass
class Expr:
    value: str
    where: str


@dataclass
class If:
    condition: str
    body: list[Any]
    otherwise: list[Any] = field(default_factory=list)
    where: str = ""


@dataclass
class Range:
    source: str
    body: list[Any]
    where: str = ""


def _tokenise(text: str, where: str) -> list[tuple[str, str, bool, bool]]:
    """``(kind, payload, trim_before, trim_after)`` for each literal or directive."""
    pieces: list[tuple[str, str, bool, bool]] = []
    position = 0
    for match in TOKEN.finditer(text):
        literal = text[position : match.start()]
        trim_before = bool(match.group(1))
        trim_after = bool(match.group(3))
        if literal:
            pieces.append(("text", literal, False, trim_before))
        pieces.append(("directive", match.group(2).strip(), trim_before, trim_after))
        position = match.end()
    tail = text[position:]
    if tail:
        pieces.append(("text", tail, False, False))
    if not any(kind == "directive" for kind, *_ in pieces) and "{{" in text:
        raise DeployCheckError(f"{where}: unbalanced template action")
    return pieces


def _parse(pieces: list[tuple[str, str, bool, bool]], where: str, index: int = 0) -> tuple[list[Any], int]:
    """Recursive-descent parse of the token stream into nodes. Returns ``(nodes, next_index)``."""
    nodes: list[Any] = []
    while index < len(pieces):
        kind, payload, _, trim_after = pieces[index]
        if kind == "text":
            value = payload.lstrip() if trim_after else payload
            if value:
                nodes.append(Text(value))
            index += 1
            continue
        if payload in {"end", "else"}:
            return nodes, index
        if payload.startswith("if "):
            condition = payload[3:].strip()
            body, index = _parse(pieces, where, index + 1)
            otherwise: list[Any] = []
            if index < len(pieces) and pieces[index][1] == "else":
                otherwise, index = _parse(pieces, where, index + 1)
            if index >= len(pieces) or pieces[index][1] != "end":
                raise DeployCheckError(f"{where}: an `if` block without `{{{{ end }}}}`")
            nodes.append(If(condition=condition, body=body, otherwise=otherwise, where=where))
            index += 1
            continue
        if payload.startswith("range "):
            source = payload[6:].strip()
            body, index = _parse(pieces, where, index + 1)
            if index >= len(pieces) or pieces[index][1] != "end":
                raise DeployCheckError(f"{where}: a `range` block without `{{{{ end }}}}`")
            nodes.append(Range(source=source, body=body, where=where))
            index += 1
            continue
        # A bare substitution, optionally piped: the only remaining form that is supported. The
        # pattern is checked explicitly rather than "anything that is not a keyword", so that
        # `{{ include "x" . }}` or `{{ default "a" .Values.b }}` is refused by name instead of
        # being substituted as a literal string and reported as a pass.
        head, _, pipe = payload.partition("|")
        if EXPRESSION_OK.match(head.strip()) and (not pipe or pipe.strip() in SUPPORTED_PIPES):
            nodes.append(Expr(value=payload, where=where))
            index += 1
            continue
        raise DeployCheckError(
            f"{where}: unsupported template construct {{{{ {payload} }}}}; this checker implements "
            f"{SUPPORTED_TEMPLATE_DOC}"
        )
    return nodes, index


def _lookup(values: dict[str, Any], dotted: str, where: str) -> Any:
    node: Any = values
    for part in dotted.split("."):
        if not isinstance(node, dict) or part not in node:
            raise DeployCheckError(f"{where}: .Values.{dotted} is not declared in values.yaml")
        node = node[part]
    return node


def _resolve(expression: str, values: dict[str, Any], item: Any, where: str) -> Any:
    """Resolve a single expression: a `.Values` path, `.` , or `.field` inside a range."""
    expression = expression.strip()
    if expression == ".":
        return item
    if expression.startswith(".Values."):
        return _lookup(values, expression[len(".Values.") :], where)
    if expression.startswith(".") and item is not None:
        key = expression[1:]
        if isinstance(item, dict) and key in item:
            return item[key]
        raise DeployCheckError(f"{where}: {expression!r} is not a field of the ranged item")
    raise DeployCheckError(
        f"{where}: unsupported expression {expression!r}; this checker implements {SUPPORTED_TEMPLATE_DOC}"
    )


def _evaluate(expression: str, values: dict[str, Any], item: Any, where: str) -> Any:
    parts = [part.strip() for part in expression.split("|")]
    value = _resolve(parts[0], values, item, where)
    for pipe in parts[1:]:
        if pipe == "quote":
            if not isinstance(value, str):
                raise DeployCheckError(f"{where}: `| quote` applied to a non-string value {value!r}")
            value = f'"{value}"'
        elif pipe == "int64":
            if isinstance(value, bool):
                raise DeployCheckError(f"{where}: `| int64` applied to a boolean value {value!r}")
            try:
                value = int(value)
            except (TypeError, ValueError) as exc:
                raise DeployCheckError(f"{where}: `| int64` applied to a non-number {value!r}") from exc
        else:
            raise DeployCheckError(
                f"{where}: unsupported pipe {pipe!r}; this checker implements {SUPPORTED_TEMPLATE_DOC}"
            )
    return value


def _go_float(value: float) -> str:
    """Format a ``float64`` the way Helm's templates do: Go's ``%v``, i.e. shortest ``%g``.

    This is not a detail. Helm loads ``values.yaml`` through YAML → JSON → ``map[string]any``, so
    *every* number in a values file arrives in a template as a ``float64``; Go prints a ``float64``
    with the shortest representation that round-trips, in scientific notation once the exponent
    falls outside ``-4 <= exp < 6``. So ``67108864`` renders as ``6.7108864e+07`` — and a chart that
    pastes that into a TOML policy writes a *float* where the document says integer.

    The table in ``tests/test_deploy_check.py`` was produced by running Helm itself (``helm
    template``, Helm v3.16.3, 2026-10-15) over a chart containing those exact values. This function
    exists because the checker's whole claim is that it renders what Helm renders, and the day it
    renders something else is the day its verdicts stop meaning anything.
    """
    if value != value or value in (float("inf"), float("-inf")):  # pragma: no cover - refused earlier
        return str(value)
    text = repr(float(value))
    exponent = 0
    if "e" in text or "E" in text:
        text, _, suffix = text.partition("e")
        exponent = int(suffix)
    sign = ""
    if text.startswith("-"):
        sign, text = "-", text[1:]
    whole, _, fraction = text.partition(".")
    if whole.lstrip("0"):
        point = len(whole.lstrip("0")) + exponent
        digits = (whole + fraction).lstrip("0")
    else:
        leading = len(fraction) - len(fraction.lstrip("0"))
        point = -leading + exponent
        digits = fraction.lstrip("0")
    digits = digits.rstrip("0") or "0"
    if digits == "0":
        # Go prints negative zero as `-0`; a values file that says `-0` should render as it was
        # written rather than being quietly normalised.
        return sign + "0"
    normalised = point - 1
    if normalised < -4 or normalised >= 6:
        head, tail = digits[0], digits[1:]
        mantissa = head + ("." + tail if tail else "")
        return f"{sign}{mantissa}e{'+' if normalised >= 0 else '-'}{abs(normalised):02d}"
    if normalised >= 0:
        head = digits[: normalised + 1].ljust(normalised + 1, "0")
        tail = digits[normalised + 1 :]
        return sign + head + ("." + tail if tail else "")
    return sign + "0." + "0" * (-normalised - 1) + digits


def _helm_numbers(node: Any) -> Any:
    """Convert a values tree to what Helm's templates actually receive: ``float64`` numbers.

    Claiming to render what Helm renders while keeping Python's ``int`` would be a checked-in
    fiction: it is the reason the static render disagreed with ``helm template`` on this chart's
    two MiB-scale policy numbers, and the reason the disagreement was invisible.
    """
    if isinstance(node, bool):
        return node
    if isinstance(node, int):
        return float(node)
    if isinstance(node, float):
        return node
    if isinstance(node, dict):
        return {key: _helm_numbers(value) for key, value in node.items()}
    if isinstance(node, list):
        return [_helm_numbers(value) for value in node]
    return node


def _helm_scalar(value: Any) -> str:
    """The text Go's ``%v`` would print for a template's scalar value."""
    if isinstance(value, bool):
        return "true" if value else "false"
    if isinstance(value, int):
        # An `int64` from a filter: a real integer, printed exactly, which is the whole point of
        # writing the filter in the template.
        return str(value)
    if isinstance(value, float):
        return _go_float(value)
    return str(value)


def _render_nodes(nodes: list[Any], values: dict[str, Any], item: Any, where: str) -> str:
    out: list[str] = []
    for node in nodes:
        if isinstance(node, Text):
            out.append(node.value)
        elif isinstance(node, Expr):
            value = _evaluate(node.value, values, item, node.where)
            if not isinstance(value, str | int | float | bool):
                raise DeployCheckError(f"{where}: {node.value!r} does not render as a scalar")
            out.append(_helm_scalar(value))
        elif isinstance(node, If):
            condition = node.condition
            negate = condition.startswith("not ")
            if negate:
                condition = condition[4:].strip()
            value = _evaluate(condition, values, item, node.where)
            truthy = bool(value) is not negate
            out.append(_render_nodes(node.body if truthy else node.otherwise, values, item, where))
        elif isinstance(node, Range):
            source = _evaluate(node.source, values, item, node.where)
            if not isinstance(source, list):
                raise DeployCheckError(f"{where}: `range` needs a list, got {type(source).__name__}")
            for entry in source:
                out.append(_render_nodes(node.body, values, entry, where))
    return "".join(out)


def render(template: str, values: dict[str, Any], where: str) -> str:
    """Render ``template`` with ``values`` under the declared subset.

    The values are converted to the types Helm's templates actually receive before anything is
    substituted, because a renderer that is *almost* Helm is worse than none: it produces confident
    text about a document no cluster would ever see (``_helm_numbers``).
    """
    values = _helm_numbers(values)
    pieces = _tokenise(template, where)
    nodes, index = _parse(pieces, where)
    if index != len(pieces):  # pragma: no cover - _parse consumes end/else only via blocks
        raise DeployCheckError(f"{where}: unexpected {pieces[index][1]!r}")
    return _render_nodes(nodes, values, None, where)


def render_chart(chart: Path, values: dict[str, Any] | None = None) -> dict[str, str]:
    """Render every template in ``chart`` with ``values`` (default: the chart's own values.yaml)."""
    if values is None:
        values = load_yaml(chart / "values.yaml")
    rendered = {}
    for template in sorted((chart / "templates").glob("*")):
        if template.name.endswith("/"):
            continue
        rendered[template.name] = render(template.read_text(encoding="utf-8"), values, str(template))
    if not rendered:
        raise DeployCheckError(f"{chart}/templates is empty")
    return rendered


def load_yaml(path: Path) -> Any:
    yaml = _yaml(where=None)
    with path.open("rb") as handle:
        return yaml.safe_load(handle)


def _yaml(where: str | None):
    try:
        import yaml  # noqa: PLC0415 - the dependency is optional and the failure is reported
    except ImportError as exc:  # pragma: no cover - covered in a subprocess: see the test named
        # `test_a_missing_pyyaml_is_exit_2_with_a_reason_never_a_pass`, which shadows this import
        # rather than uninstalling the package.
        # `raise SystemExit("text")` prints the text and exits **1** — the code this tool uses for
        # "a check failed". That would make "could not run" indistinguishable from "found a
        # defect", which is the one distinction an operator script has to get right, so the code is
        # set explicitly and the reason is written to stderr.
        print(
            "deploy_check: PyYAML is not installed, so the deployment artefacts cannot be read.\n"
            + (f"(while reading {where})\n" if where else "")
            + "This is not a pass: install it (`pip install pyyaml`, or `pip install -e '.[deploy]'`) "
            "and run this again.\n"
            "Neither this script nor `make deploy-check` installs it for you, deliberately: a check "
            "that fetches its own dependencies is a check whose result depends on what it fetched.\n"
            f"({exc})",
            file=sys.stderr,
        )
        raise SystemExit(2) from exc
    return yaml


#: Templates that are Kubernetes documents rather than prose (NOTES.txt is rendered and checked for
#: substitution errors like any other template, but it is not YAML and is not parsed as such).
YAML_SUFFIXES = {".yaml", ".yml"}


def documents(text: str, where: str) -> list[dict[str, Any]]:
    """Every non-empty YAML document in ``text``, each required to be a mapping with a kind."""
    yaml = _yaml(where)
    loaded: list[dict[str, Any]] = []
    try:
        raw = list(yaml.safe_load_all(text))
    except yaml.YAMLError as exc:
        raise DeployCheckError(f"{where}: not valid YAML: {exc}") from exc
    for index, document in enumerate(raw):
        if document is None:
            continue
        if not isinstance(document, dict):
            raise DeployCheckError(f"{where}: document {index} is a {type(document).__name__}, not a mapping")
        loaded.append(document)
    return loaded


# --------------------------------------------------------------------------- #
# The checks
# --------------------------------------------------------------------------- #


@dataclass
class Result:
    name: str
    problems: list[str] = field(default_factory=list)

    @property
    def ok(self) -> bool:
        return not self.problems


CHECKS: list[Any] = []


def check(name: str):
    def wrapper(function):
        CHECKS.append((name, function))
        return function

    return wrapper


def _containers(document: dict[str, Any]) -> Iterator[dict[str, Any]]:
    yield from document.get("spec", {}).get("template", {}).get("spec", {}).get("containers", []) or []


def _images(document: dict[str, Any]) -> Iterator[str]:
    for container in _containers(document):
        image = container.get("image")
        if isinstance(image, str):
            yield image


def _pods() -> Iterator[tuple[str, dict[str, Any]]]:
    """Every Deployment/StatefulSet/DaemonSet rendered from the chart or written by hand."""
    for path, text in _all_documents():
        for document in documents(text, path):
            if document.get("kind") in {"Deployment", "StatefulSet", "DaemonSet", "Job", "CronJob"}:
                yield path, document


def _kubernetes_documents() -> Iterator[tuple[str, str]]:
    """The Kubernetes artefacts: `deploy/kubernetes/` and the chart's rendered YAML templates.

    `deploy/compose.yaml` is a Docker Compose file, not a Kubernetes document, and is checked as
    such; kustomization.yaml is a Kubernetes document with an apiVersion and a kind, so it is in.
    """
    for path, text in _all_documents():
        if "kubernetes" in path or path.endswith(".yaml") and "templates" in path:
            yield path, text


def _all_documents() -> Iterator[tuple[str, str]]:
    """Every YAML artefact in deploy/, chart templates rendered."""
    chart = DEPLOY / "helm" / "docket"
    for name, text in render_chart(chart).items():
        if Path(name).suffix in YAML_SUFFIXES:
            yield f"{chart}/templates/{name}", text
    for path in sorted(DEPLOY.rglob("*.yaml")):
        if "helm" in path.parts:
            continue
        yield str(path), path.read_text(encoding="utf-8")


@check("chart.metadata")
def chart_metadata() -> list[str]:
    chart = DEPLOY / "helm" / "docket"
    problems: list[str] = []
    metadata = load_yaml(chart / "Chart.yaml")
    if metadata.get("apiVersion") != "v2":
        problems.append(f"Chart.yaml apiVersion is {metadata.get('apiVersion')!r}, not 'v2'")
    for key in ("name", "description", "version", "appVersion", "home", "sources"):
        if not metadata.get(key):
            problems.append(f"Chart.yaml is missing {key!r}")
    if not re.fullmatch(r"\d+\.\d+\.\d+", str(metadata.get("version", ""))):
        problems.append(f"Chart.yaml version {metadata.get('version')!r} is not x.y.z")
    if not (chart / "values.yaml").exists() or not (chart / "templates").is_dir():
        problems.append("the chart needs values.yaml and templates/")
    return problems


@check("chart.values-are-an-interface")
def chart_values_interface() -> list[str]:
    """Every value a template uses is declared; every declared value is used."""
    chart = DEPLOY / "helm" / "docket"
    values = load_yaml(chart / "values.yaml")

    declared: set[str] = set()

    def walk(prefix: str, node: Any) -> None:
        if isinstance(node, dict):
            for key, value in node.items():
                walk(f"{prefix}.{key}" if prefix else str(key), value)
        else:
            declared.add(prefix)

    walk("", values)

    used: set[str] = set()
    for template in sorted((chart / "templates").glob("*")):
        text = template.read_text(encoding="utf-8")
        for match in VALUES_REF.finditer(text):
            used.add(match.group(1))
        # a range over a list still counts as using its items' parent path
        for match in re.finditer(r"range\s+\.Values\.([A-Za-z0-9_.]+)", text):
            used.add(match.group(1))

    problems = [f"template uses undeclared .Values.{name}" for name in sorted(used - declared)]
    problems += [f"values.yaml declares .Values.{name}, which no template uses" for name in sorted(declared - used)]
    return problems


@check("chart.renders")
def chart_renders() -> list[str]:
    """The chart renders under its own values, and every rendered document is valid YAML."""
    problems: list[str] = []
    for name, text in render_chart(DEPLOY / "helm" / "docket").items():
        if not text.strip():
            problems.append(f"{name} renders to nothing under the chart's own values")
            continue
        if Path(name).suffix not in YAML_SUFFIXES:
            continue
        try:
            documents(text, name)
        except DeployCheckError as exc:
            problems.append(str(exc))
    return problems


@check("documents.are-declarations")
def documents_are_declarations() -> list[str]:
    problems: list[str] = []
    seen = 0
    for path, text in _kubernetes_documents():
        for document in documents(text, path):
            seen += 1
            if not document.get("apiVersion") or not document.get("kind"):
                problems.append(f"{path}: a document without apiVersion/kind")
    if seen == 0:
        problems.append("no Kubernetes documents found under deploy/")
    return problems


@check("images.are-pinned")
def images_are_pinned() -> list[str]:
    problems: list[str] = []
    for path, document in _pods():
        for image in _images(document):
            tag = image.rsplit("/", 1)[-1].split(":", 1)
            if len(tag) == 1 or tag[1] in LATEST_TAGS:
                problems.append(f"{path}: image {image!r} has no pinned tag")
    return problems


@check("pod.is-hardened")
def pod_is_hardened() -> list[str]:
    problems: list[str] = []
    for path, document in _pods():
        spec = document.get("spec", {}).get("template", {}).get("spec", {})
        context = spec.get("securityContext") or {}
        if context.get("runAsNonRoot") is not True:
            problems.append(f"{path}: pod securityContext.runAsNonRoot is not true")
        if not isinstance(context.get("runAsUser"), int) or context.get("runAsUser") in (0,):
            problems.append(f"{path}: pod securityContext.runAsUser is not a non-zero integer")
        if not context.get("seccompProfile"):
            problems.append(f"{path}: pod securityContext has no seccompProfile")
        for key in ("hostNetwork", "hostPID", "hostIPC"):
            if spec.get(key):
                problems.append(f"{path}: {key} is enabled")
        for container in _containers(document):
            name = container.get("name", "?")
            security = container.get("securityContext") or {}
            if security.get("allowPrivilegeEscalation") is not False:
                problems.append(f"{path}: container {name} does not set allowPrivilegeEscalation: false")
            if security.get("readOnlyRootFilesystem") is not True:
                problems.append(f"{path}: container {name} does not set readOnlyRootFilesystem: true")
            if security.get("privileged"):
                problems.append(f"{path}: container {name} is privileged")
            caps = (security.get("capabilities") or {}).get("drop") or []
            if "ALL" not in caps:
                problems.append(f"{path}: container {name} does not drop ALL capabilities")
        for volume in spec.get("volumes") or []:
            if "hostPath" in volume:
                problems.append(f"{path}: volume {volume.get('name')} uses hostPath")
    return problems


@check("containers.have-resources")
def containers_have_resources() -> list[str]:
    problems: list[str] = []
    for path, document in _pods():
        for container in _containers(document):
            name = container.get("name", "?")
            resources = container.get("resources") or {}
            for section in ("requests", "limits"):
                values = resources.get(section) or {}
                for key in ("cpu", "memory"):
                    if not values.get(key):
                        problems.append(f"{path}: container {name} has no {section}.{key}")
    return problems


@check("probes.use-a-declared-port")
def probes_use_a_declared_port() -> list[str]:
    """A probe on a port the container does not declare is a pod that never becomes Ready."""
    problems: list[str] = []
    pattern = re.compile(r"127\.0\.0\.1:(\d+)")
    for path, document in _pods():
        for container in _containers(document):
            name = container.get("name", "?")
            declared = {str(port.get("containerPort")) for port in container.get("ports") or []}
            probes = [
                (kind, container[kind])
                for kind in ("livenessProbe", "readinessProbe", "startupProbe")
                if container.get(kind)
            ]
            if not probes and container.get("ports"):
                # A container with no declared port may be a job that runs to completion; one that
                # publishes a port is a server, and a server nobody probes is a server whose death
                # is discovered by the next request.
                problems.append(f"{path}: container {name} declares a port but no probes")
            for kind, probe in probes:
                commands = probe.get("exec", {}).get("command") or []
                for command in commands:
                    for port in pattern.findall(command):
                        if port not in declared:
                            problems.append(
                                f"{path}: container {name} {kind} probes 127.0.0.1:{port}, "
                                f"which is not a declared containerPort ({sorted(declared) or 'none'})"
                            )
                if not commands and not probe.get("httpGet") and not probe.get("tcpSocket"):
                    problems.append(f"{path}: container {name} {kind} has no handler")
    return problems


@check("deployment.one-writer")
def deployment_one_writer() -> list[str]:
    """One writer per evidence directory: `Recreate`, and a PVC where the policy says it is."""
    problems: list[str] = []
    for path, document in _pods():
        if document.get("kind") != "Deployment":
            continue
        strategy = document.get("spec", {}).get("strategy", {}).get("type")
        if strategy != "Recreate":
            problems.append(f"{path}: strategy.type is {strategy!r}; two pods would share one evidence volume")
        spec = document.get("spec", {}).get("template", {}).get("spec", {})
        mounts = {
            mount.get("mountPath")
            for container in _containers(document)
            for mount in container.get("volumeMounts") or []
        }
        if "/work/.docket" not in mounts:
            problems.append(f"{path}: nothing is mounted at /work/.docket, where the policy points --docket-dir")
        names = {volume.get("name") for volume in spec.get("volumes") or []}
        for container in _containers(document):
            for mount in container.get("volumeMounts") or []:
                if mount.get("name") not in names:
                    problems.append(f"{path}: mount {mount.get('name')!r} has no matching volume")
    return problems


def _integer_policy_keys() -> set[str]:
    """The policy keys whose documented type is an integer, derived from the dataclasses.

    Deriving the list means it cannot drift: adding ``int`` field to ``Caps`` or ``Resilience``
    puts it under this check without anyone remembering to.
    """
    from dataclasses import fields  # noqa: PLC0415
    from decimal import Decimal  # noqa: PLC0415
    from typing import get_args, get_type_hints  # noqa: PLC0415

    from docket.policy import Cache, Caps, Resilience  # noqa: PLC0415

    keys: set[str] = set()
    for section, cls in (("caps", Caps), ("resilience", Resilience), ("cache", Cache)):
        hints = get_type_hints(cls)
        for policy_field in fields(cls):
            options = get_args(hints[policy_field.name]) or (hints[policy_field.name],)
            if int in options and not any(option in options for option in (float, Decimal, str)):
                keys.add(f"{section}.{policy_field.name}")
    return keys


def _integer_fields_that_arrived_as_floats(
    path: str, key: str, body: str, parsed: dict[str, Any], integer_keys: set[str]
) -> list[str]:
    """Report an integer key that the rendered document spells as a float, with the line quoted."""
    problems: list[str] = []
    lines = {line.split("=", 1)[0].strip(): line.strip() for line in body.splitlines() if "=" in line}
    for dotted in sorted(integer_keys):
        section, _, field = dotted.partition(".")
        table = parsed.get(section)
        if not isinstance(table, dict) or field not in table:
            continue
        value = table[field]
        if isinstance(value, int):  # a bool is an int here too, and neither is a float
            continue
        rendered = lines.get(field, f"{field} = {value!r}")
        problems.append(
            f"{path}: {key}: {rendered} — {dotted} is documented as an integer, and TOML reads that "
            f"as a {type(value).__name__}. Helm renders every number in values.yaml as a float64, so "
            f"a value at or above 1e6 comes out in scientific notation unless the template says what "
            f"type it means: write it as {{{{ .Values.<path> | int64 }}}}"
        )
    return problems


@check("configmap.policy-parses")
def configmap_policy_parses() -> list[str]:
    """Every policy embedded in a ConfigMap is read by Docket's own policy loader.

    Reading is not enough on its own. A policy written by a *template* can be readable and still
    wrong: Helm hands a template a ``float64`` for every number in ``values.yaml``, so a large
    integer pasted into the document arrives as ``6.7108864e+07``, which TOML reads as a float —
    accepted by the loader (a whole float is a whole number) and silently a different type from
    the one the key documents. Values that must be integers are therefore checked as integers,
    against the type the policy dataclasses declare rather than a list kept in step by hand.
    """
    sys.path.insert(0, str(HERE / "src"))
    from docket.policy import Policy  # noqa: PLC0415 - imported here so the failure is legible

    integer_keys = _integer_policy_keys()
    problems: list[str] = []
    seen = 0
    for path, text in _all_documents():
        for document in documents(text, path):
            if document.get("kind") != "ConfigMap":
                continue
            for key, body in (document.get("data") or {}).items():
                if not str(key).endswith(".toml"):
                    continue
                seen += 1
                try:
                    parsed = tomllib.loads(body)
                except tomllib.TOMLDecodeError as exc:
                    problems.append(f"{path}: {key} is not valid TOML: {exc}")
                    continue
                loader = getattr(Policy, "from_dict", None)
                if loader is None:
                    if "caps" not in parsed:
                        problems.append(f"{path}: {key} has no [caps] section")
                    continue
                try:
                    loader(parsed)
                except Exception as exc:  # noqa: BLE001 - whatever the loader says is the answer
                    problems.append(f"{path}: {key} is not a policy Docket accepts: {exc}")
                problems.extend(_integer_fields_that_arrived_as_floats(path, key, body, parsed, integer_keys))
    if seen == 0:
        problems.append("no policy TOML found in any ConfigMap: the manifests do not configure a run")
    return problems


@check("networkpolicy.default-deny")
def networkpolicy_default_deny() -> list[str]:
    problems: list[str] = []
    seen = 0
    for path, text in _all_documents():
        for document in documents(text, path):
            if document.get("kind") != "NetworkPolicy":
                continue
            seen += 1
            spec = document.get("spec") or {}
            types = spec.get("policyTypes") or []
            if "Ingress" not in types or "Egress" not in types:
                problems.append(f"{path}: policyTypes must include Ingress and Egress, got {types}")
            if spec.get("ingress") != []:
                problems.append(f"{path}: ingress is not empty; nothing should reach a live run")
            egress = spec.get("egress") or []
            if not egress:
                problems.append(f"{path}: no egress rules: the pod could not resolve DNS or reach a provider")
            if not spec.get("podSelector"):
                problems.append(f"{path}: no podSelector, so the policy applies to nothing")
    if seen == 0:
        problems.append("no NetworkPolicy in the manifests")
    return problems


@check("compose.waits-and-is-read-only")
def compose_waits_and_is_read_only() -> list[str]:
    problems: list[str] = []
    compose = load_yaml(DEPLOY / "compose.yaml")
    services = compose.get("services") or {}
    for required in ("provider", "boundary", "verify"):
        if required not in services:
            problems.append(f"compose.yaml has no {required!r} service")
    verify = services.get("verify") or {}
    conditions = [(dependency or {}).get("condition") for dependency in (verify.get("depends_on") or {}).values()]
    if "service_completed_successfully" not in conditions:
        problems.append("the verifier does not wait for the run to finish before verifying")
    for name, service in services.items():
        if service.get("ports"):
            problems.append(
                f"service {name} publishes ports; a boundary and a scripted provider stay on the compose network"
            )
        if service.get("read_only") is not True:
            problems.append(f"service {name} does not set read_only: true")
        caps = service.get("cap_drop") or []
        if "ALL" not in caps:
            problems.append(f"service {name} does not drop ALL capabilities")
        for mount in service.get("volumes") or []:
            if isinstance(mount, str) and "/etc/docket" in mount and not mount.endswith(":ro"):
                problems.append(f"service {name} mounts the policy read-write: {mount}")
        if name != "verify" and not service.get("healthcheck"):
            problems.append(f"service {name} has no healthcheck")
    evidence_mounts = [
        mount for mount in (verify.get("volumes") or []) if isinstance(mount, str) and "/work/.docket" in mount
    ]
    if not evidence_mounts or not all(mount.endswith(":ro") for mount in evidence_mounts):
        problems.append("the verifier mounts the evidence volume writable")
    return problems


@check("kustomization.paths-exist")
def kustomization_paths_exist() -> list[str]:
    problems: list[str] = []
    path = DEPLOY / "kubernetes" / "kustomization.yaml"
    if not path.exists():
        return [f"{path} does not exist"]
    resource_list = load_yaml(path).get("resources") or []
    if not resource_list:
        problems.append("kustomization.yaml lists no resources")
    for entry in resource_list:
        target = path.parent / entry
        if not target.exists():
            problems.append(f"kustomization.yaml references {entry}, which does not exist")
            continue
        if not documents(target.read_text(encoding="utf-8"), str(target)):
            problems.append(f"kustomization.yaml references {entry}, which holds no documents")
    return problems


@check("dockerfile.is-buildable-by-inspection")
def dockerfile_is_buildable_by_inspection() -> list[str]:
    """The Dockerfile's copies exist, it installs as a non-root user, and it hides no surprises."""
    problems: list[str] = []
    path = DEPLOY / "Dockerfile"
    if not path.exists():
        return [f"{path} does not exist"]
    text = path.read_text(encoding="utf-8")
    for match in re.finditer(r"^\s*COPY\s+(?:--\S+\s+)*(.+)$", text, re.M):
        sources = match.group(1).split()
        if len(sources) < 2:
            problems.append(f"Dockerfile: COPY {match.group(1)!r} has no destination")
            continue
        from_stage = "--from=" in match.group(0)
        for source in sources[:-1]:
            if from_stage or source in {".", "./"} or source.startswith(("http", "/")):
                # `COPY --from=build /install /usr/local` copies from another stage: not a path in
                # this repository, and checking it would be checking the wrong thing.
                continue
            if not (ROOT / source).exists():
                problems.append(f"Dockerfile copies {source!r}, which is not in the repository")
    if re.search(r"^\s*ADD\s", text, re.M):
        problems.append("Dockerfile uses ADD; COPY is the directive that does not unpack or fetch")
    if re.search(r"curl[^\n]*\|\s*(?:ba)?sh", text):
        problems.append("Dockerfile pipes a download into a shell")
    users = re.findall(r"^\s*USER\s+(\S+)", text, re.M)
    if not users:
        problems.append("Dockerfile never sets USER: the container would run as root")
    definite = [name for name in users if name in {"root", "0", "0:0", "root:root"}]
    if definite or not any(name not in {"root", "0"} for name in users):
        problems.append(f"Dockerfile runs as {users[-1]!r}; a supervised agent needs no root")
    if "STOPSIGNAL" not in text:
        problems.append("Dockerfile sets no STOPSIGNAL; SIGTERM is what lets a run close its receipt")
    if re.search(r"^\s*ENV\s+\S*(?:KEY|TOKEN|SECRET|PASSWORD)\S*=", text, re.M | re.I):
        problems.append("Dockerfile bakes a credential-looking variable into the image")
    if not (ROOT / ".dockerignore").exists():
        problems.append("no .dockerignore: the build context would carry .git, ledgers and dist/")
    return problems


@check("workflows.parse")
def workflows_parse() -> list[str]:
    """The CI workflows are deployment artefacts too: they are what runs the checks.

    A YAML file that does not parse is a workflow that silently does not exist — GitHub reports a
    syntax error and runs nothing, which from the outside looks exactly like a green build. This
    caught a real defect in this repository's own CI while the deploy job was being added: an
    unquoted step name containing a colon ("deploy artefacts (static: no container ...)").
    """
    problems: list[str] = []
    workflows = sorted((ROOT / ".github" / "workflows").glob("*.y*ml"))
    if not workflows:
        return ["no CI workflows found"]
    for path in workflows:
        try:
            document = load_yaml(path)
        except Exception as exc:  # noqa: BLE001 - any parse failure is the finding
            problems.append(f"{path}: does not parse as YAML: {exc}")
            continue
        if not isinstance(document, dict):
            problems.append(f"{path}: not a mapping")
            continue
        jobs = document.get("jobs")
        if not isinstance(jobs, dict) or not jobs:
            problems.append(f"{path}: no jobs")
            continue
        for name, job in jobs.items():
            if not isinstance(job, dict):
                problems.append(f"{path}: job {name!r} is not a mapping")
                continue
            if job.get("runs-on") in (None, ""):
                problems.append(f"{path}: job {name!r} has no runs-on")
            steps = job.get("steps")
            if not isinstance(steps, list) or not steps:
                problems.append(f"{path}: job {name!r} has no steps")
                continue
            for index, step in enumerate(steps):
                if not isinstance(step, dict) or not (step.get("uses") or step.get("run")):
                    problems.append(f"{path}: job {name!r} step {index} neither uses an action nor runs a command")
    return problems


@check("references.resolve")
def references_resolve() -> list[str]:
    """Every path referenced from an artefact in deploy/ exists."""
    problems: list[str] = []
    # A backtick is the usual way these paths are written in prose (`docs/testing.md`), so it counts
    # as a boundary too — a checker that only noticed unquoted paths would miss most of them.
    pattern = re.compile(
        r"(?:^|[\s(`])((?:deploy|docs|src|spec|tests|tools)/[A-Za-z0-9_./-]+\.(?:md|py|yaml|toml|json))"
    )
    for path in sorted(DEPLOY.rglob("*")):
        if not path.is_file() or path.suffix not in {".yaml", ".yml", ".md", ".json"}:
            continue
        for reference in pattern.findall(path.read_text(encoding="utf-8")):
            if not (ROOT / reference).exists():
                problems.append(f"{path}: references {reference}, which does not exist")
    return problems


# --------------------------------------------------------------------------- #
# Running them
# --------------------------------------------------------------------------- #


def run(selected: list[str] | None = None) -> tuple[list[Result], list[str]]:
    results: list[Result] = []
    for name, function in CHECKS:
        if selected and not any(name.startswith(prefix) for prefix in selected):
            continue
        result = Result(name=name)
        try:
            result.problems = list(function() or [])
        except DeployCheckError as exc:
            result.problems = [str(exc)]
        except Exception as exc:  # noqa: BLE001 - a crash in a check is a failed check, not a traceback
            result.problems = [f"{type(exc).__name__}: {exc}"]
        results.append(result)
    # The render is reported by `chart.renders` when it fails, so it must not take the whole run
    # down with a traceback: `run()` returns what it has, and the failure is in the results.
    try:
        yaml_only = {
            name: text
            for name, text in render_chart(DEPLOY / "helm" / "docket").items()
            if Path(name).suffix in YAML_SUFFIXES
        }
    except DeployCheckError:
        yaml_only = {}
    manifest = "".join(f"# {name}\n{text}\n---\n" for name, text in sorted(yaml_only.items()))
    return results, [manifest]


def main(argv: list[str] | None = None) -> int:
    parser = argparse.ArgumentParser(
        prog="tools/deploy_check.py",
        description="Check deploy/ statically: it cannot run a container, and it does not pretend to.",
    )
    parser.add_argument("--only", action="append", help="run only checks whose name starts with this")
    parser.add_argument("--root", type=Path, help="check this tree instead of the repository (for tests)")
    parser.add_argument("--json", action="store_true", help="machine-readable results")
    parser.add_argument("--print-rendered", action="store_true", help="print the rendered chart and stop")
    args = parser.parse_args(argv)
    if args.root:
        set_root(args.root)

    if args.print_rendered:
        rendered = render_chart(DEPLOY / "helm" / "docket")
        for name in sorted(rendered):
            sys.stdout.write(f"# ---- {name} ----\n{rendered[name]}\n")
        return 0

    results, rendered = run(args.only)
    failures = [result for result in results if not result.ok]
    if args.json:
        print(
            json.dumps(
                {
                    "checks": [{"name": r.name, "ok": r.ok, "problems": r.problems} for r in results],
                    "passed": len(results) - len(failures),
                    "failed": len(failures),
                    "rendered_documents": len(documents(rendered[0], "rendered chart")),
                },
                indent=2,
            )
        )
    else:
        for result in results:
            if result.ok:
                print(f"  PASS  {result.name}")
            else:
                print(f"  FAIL  {result.name}")
                for problem in result.problems:
                    print(f"          {problem}")
        print(
            f"\n{len(results) - len(failures)}/{len(results)} deploy checks passed "
            f"({len(documents(rendered[0], 'rendered chart'))} Kubernetes documents rendered and read)"
        )
        print(
            "What this does not do: run a container, apply a manifest, or reach a cluster. "
            "No container runtime or kubectl exists in the environment this ran in."
        )
    return 1 if failures else 0


if __name__ == "__main__":
    raise SystemExit(main())