orchestrator/agent-team/agent_team/nodes/build_verify_subgraph.py

"""P3-INERT build -> verify subgraph TOPOLOGY (design §3.3, §7.1 P3).

This module is the **wiring topology** for the Plane-2 build -> verify stage::

    ... -> REVIEW (route "build") -> BUILD -> VERIFY -> {approved | build | parked}

It produces the BUILD node, the VERIFY node, and the
:func:`route_after_verify` conditional-edge function so the Integrate phase can
hang them off :func:`agent_team.graph.build_graph` as a subgraph reachable from
the review loop's ``"build"`` route. It assembles NOTHING by itself: it does not
call :func:`agent_team.graph.build_graph`, and the production default pipeline
stays P2 (clarify -> plan -> review). Hooking this subgraph in is a deliberate,
opt-in Integrate-phase edit.

==============================  INERT / HARD-GATE  ==========================
P3 (builders + verifier) is HARD-GATED behind ``/sh-security-review`` + a
GPT-4.1 cross-review of the §3.3.2 CI apply/verify trust boundary BEFORE it goes
live. This module is TOPOLOGY + SEAMS ONLY and MUST stay INERT:

  * **No live CI.** The VERIFY node consumes an INJECTED ``ci_result`` seam — a
    fetcher callable that, given the task state, returns the authenticated CI
    conclusion as DATA (exactly what :func:`agent_team.ci_gate.evaluate_ci_gate`
    expects). The DEFAULT fetcher returns ``None`` (the current pre-live-CI
    reality). It performs NO live CI dispatch, NO OIDC, NO network to GitHub
    Actions, NO ``git``/patch apply, and NO filesystem mutation.
  * **Fail-safe verdict.** With no ``ci_result`` (the default), the pure-code
    gate (:mod:`agent_team.ci_gate`) returns ``BLOCK`` — there is no
    authenticated pass to be had — and :func:`route_after_verify` routes the
    task to PARKED. The pipeline NEVER fabricates a pass; the gate is the sole
    pass authority.
  * **LLM stays a fix-proposer.** The verifier's LLM seam
    (:data:`agent_team.nodes.verifier.FixAdvisor`) is consulted ONLY on a
    failure to author a fix hint. It is structurally incapable of flipping the
    verdict to pass (the verdict is computed first, by the gate, and is never
    read back from the proposer — see :mod:`agent_team.nodes.verifier_llm`).

The live apply/verify path (the gated wiring of a real diff builder + a real CI
result fetcher) is held for the separate security-review + cross-review gate and
is NOT shipped or enabled here. :func:`bind_diff_builder` and
:func:`bind_ci_result_fetcher` are the injection points a leaf will use to bind
those real seams once the gate clears.
============================================================================

What this module owns (topology + seams only):

* :data:`APPROVED_ROUTE` / :data:`BUILD_ROUTE` / :data:`PARKED_ROUTE` — the
  route ids :func:`route_after_verify` returns. ``BUILD_ROUTE`` /
  ``PARKED_ROUTE`` mirror :data:`agent_team.graph.BUILD_ROUTE` /
  :data:`agent_team.graph.PARKED_ROUTE` by VALUE so the conditional-edge map the
  Integrate phase builds matches without this module importing ``graph`` (which
  would be a wiring import cycle).
* :func:`make_build_node` — factory producing the single-argument BUILD node,
  threading an injectable :class:`~agent_team.nodes.builders.DiffBuilder` into
  :func:`agent_team.nodes.builders.builders_node`.
* :func:`make_verify_node` — factory producing the single-argument VERIFY node,
  threading an injectable ``ci_result`` fetcher into
  :func:`agent_team.nodes.verifier.verifier_node` (default fetcher -> ``None``).
* :func:`route_after_verify` — the LangGraph conditional-edge function that
  reads the verdict the VERIFY node recorded and returns the next route id.
* :func:`bind_diff_builder` / :func:`bind_ci_result_fetcher` — the gated-live
  injection points (held for the security gate).

It imports the committed node + foundation contracts verbatim and redefines none
of them. No SDK is imported at module top (deferred discipline mirroring
:func:`agent_team.graph.build_sqlite_checkpointer`); it is fully unit-testable
with no network.
"""

from __future__ import annotations

from collections.abc import Callable, Mapping
from typing import Any

from agent_team.nodes.builders import DiffBuilder, builders_node
from agent_team.nodes.verifier import VerifierConfig, verifier_node
from agent_team.task_model import Phase, PipelineState

__all__ = [
    "APPROVED_ROUTE",
    "BUILD_NODE",
    "BUILD_ROUTE",
    "CiResultFetcher",
    "PARKED_ROUTE",
    "VERIFY_NODE",
    "bind_ci_result_fetcher",
    "bind_diff_builder",
    "make_build_node",
    "make_verify_node",
    "route_after_verify",
]

# --- Node names (graph vertices). ------------------------------------------
# Kept as constants so the Integrate-phase wiring references the subgraph
# vertices by name rather than by string literal.
BUILD_NODE = "build"
VERIFY_NODE = "verify"

# --- Route ids returned by route_after_verify. -----------------------------
# These mirror agent_team.graph.BUILD_ROUTE / PARKED_ROUTE by VALUE so the
# conditional-edge map the Integrate phase builds lines up without importing
# graph here (that would be a wiring import cycle). APPROVED_ROUTE is the
# build->verify-specific PASS terminus (the draft-PR endpoint); BUILD_ROUTE is
# the loop-back to the builders on a recoverable failure; PARKED_ROUTE is the
# fail-safe escalation (the only reachable route while INERT, since the default
# fetcher yields no authenticated pass).
APPROVED_ROUTE = "approved"
BUILD_ROUTE = "build"
PARKED_ROUTE = "parked"


# The injectable CI-result seam: given the task state, return the authenticated,
# patch-independent CI conclusion as a mapping (run_id / conclusion / diff_hash),
# or ``None`` when there is no authenticated result. The DEFAULT
# (:func:`_no_ci_result`) always returns ``None`` (the INERT pre-live-CI
# reality), so the gate BLOCKs and the task parks — never a fabricated pass. The
# real fetcher (read-only PAT against the GitHub Checks/Actions API) is bound via
# :func:`bind_ci_result_fetcher` only after the §3.3.2 trust boundary clears its
# security gate.
CiResultFetcher = Callable[[PipelineState], Mapping[str, Any] | None]


def _no_ci_result(state: PipelineState) -> None:
    """Default :data:`CiResultFetcher`: there is NO authenticated CI result.

    This is the INERT, pre-live-CI reality. Returning ``None`` means the
    pure-code gate (:func:`agent_team.ci_gate.evaluate_ci_gate`) has no
    authenticated conclusion to read and therefore returns ``BLOCK`` — never a
    pass. The subgraph thus fails SAFE to PARKED until a real fetcher is bound
    via :func:`bind_ci_result_fetcher` (which is held for the security gate).
    """
    return None


def make_build_node(
    *,
    diff_builder: DiffBuilder | None = None,
    config: Mapping[str, Any] | None = None,
) -> Callable[[PipelineState], dict[str, Any]]:
    """Produce the single-argument BUILD node (approved plan -> candidate diff).

    Wraps :func:`agent_team.nodes.builders.builders_node` as a one-argument
    ``PipelineState -> partial PipelineState`` closure so LangGraph can add it as
    a vertex without seeing the node's ``builder`` / ``config`` keyword params
    (LangGraph would otherwise try to inject its own ``RunnableConfig`` there —
    the same hazard :func:`agent_team.nodes.review_loop.bind_review_node`
    guards against). The injected ``diff_builder`` is threaded straight to the
    node's :class:`~agent_team.nodes.builders.DiffBuilder` seam.

    INERT: when ``diff_builder`` is ``None`` the node falls back to its committed
    default (:func:`agent_team.nodes.builders.default_diff_builder`), which fails
    LOUDLY in an un-wired environment (the billing seam raises until configured)
    rather than emitting an empty diff. The real DeepSeek path is bound via
    :func:`bind_diff_builder` once the §3.3.2 gate clears. The node itself never
    applies a patch — it emits the diff as DATA plus the box-side
    trust-control-surface scan + integrity hash.
    """

    def node(state: PipelineState) -> dict[str, Any]:
        return builders_node(state, builder=diff_builder, config=config)

    return node


def make_verify_node(
    config: VerifierConfig,
    *,
    ci_result_fetcher: CiResultFetcher | None = None,
) -> Callable[[PipelineState], PipelineState]:
    """Produce the single-argument VERIFY node (gate the CI result, decide phase).

    Wraps :func:`agent_team.nodes.verifier.verifier_node` as a one-argument
    closure over ``config`` (a :class:`~agent_team.nodes.verifier.VerifierConfig`)
    so it wires straight into LangGraph without a manage-injected ``config``
    param. The INERT ``ci_result`` seam is the key here: the node reads its CI
    conclusion from ``state["ci_results"]``, so this wrapper FETCHES that result
    via the injected ``ci_result_fetcher`` and merges it into the state BEFORE
    delegating to the node.

    The default fetcher (:func:`_no_ci_result`) returns ``None`` (the pre-live-CI
    reality). With no authenticated CI result the pure-code gate returns
    ``BLOCK`` and the node parks the task — it can NEVER fabricate a pass. The
    LLM verifier seam stays a fix-PROPOSER only (the gate is the sole pass
    authority); see :mod:`agent_team.nodes.verifier_llm`.

    The fetcher is called defensively: it receives the task state and returns the
    authenticated CI conclusion mapping (``run_id`` / ``conclusion`` /
    ``diff_hash``) or ``None``. Any value other than a mapping is treated as
    "no result" (``None``), so a malformed fetcher fails SAFE to BLOCK rather
    than smuggling something past the gate. The real read-only-PAT fetcher is
    bound via :func:`bind_ci_result_fetcher` only after the §3.3.2 trust boundary
    clears its security gate.
    """
    fetcher: CiResultFetcher = (
        ci_result_fetcher if ci_result_fetcher is not None else _no_ci_result
    )

    def node(state: PipelineState) -> PipelineState:
        fetched = fetcher(state)
        ci_result = fetched if isinstance(fetched, Mapping) else None

        # Merge the (possibly None) fetched CI result into the state the node
        # reads from, WITHOUT mutating the caller's state object. The node reads
        # ``ci_results``; a None result leaves the gate with nothing to pass on.
        scoped_state: dict[str, Any] = dict(state)
        scoped_state["ci_results"] = ci_result
        return verifier_node(scoped_state, config)

    return node


def route_after_verify(state: PipelineState) -> str:
    """LangGraph conditional-edge: the next route id after the VERIFY node.

    Reads the phase the VERIFY node recorded (the pure-code gate's verdict,
    already merged into ``current_phase`` / ``status``) and maps it to a route
    id the Integrate-phase conditional-edge map keys against:

    * gate PASS -> phase ``DONE`` -> :data:`APPROVED_ROUTE` (the draft-PR
      terminus). UNREACHABLE while INERT — the default fetcher yields no
      authenticated pass, so the gate never returns PASS.
    * gate FAIL under the build-loop budget -> phase ``BUILD`` ->
      :data:`BUILD_ROUTE` (loop back to the builders with the fix hint).
    * gate BLOCK, or FAIL at/over the budget -> phase ``PARKED`` ->
      :data:`PARKED_ROUTE` (escalate to human + GPT cross-review; ALARM).

    FAILS SAFE: any unexpected / missing phase routes to
    :data:`PARKED_ROUTE` rather than advancing, so an ambiguous state parks for a
    human instead of shipping. The verdict is owned entirely by the gate (the
    node already applied it); this function only reads the recorded phase.
    """
    phase = state.get("current_phase")

    if phase == Phase.DONE.value:
        return APPROVED_ROUTE
    if phase == Phase.BUILD.value:
        return BUILD_ROUTE
    if phase == Phase.PARKED.value:
        return PARKED_ROUTE
    # Unknown / missing phase (the node always sets one of the above) -> park
    # fail-closed rather than advancing an ambiguous state.
    return PARKED_ROUTE


def bind_diff_builder(
    diff_builder: DiffBuilder,
) -> Callable[[PipelineState], dict[str, Any]]:
    """Bind the REAL diff builder into a BUILD node (GATED-LIVE injection point).

    Thin convenience over :func:`make_build_node` for the leaf that, once the
    §3.3.2 trust boundary clears ``/sh-security-review`` + the GPT-4.1
    cross-review, binds the real DeepSeek ``fast_coder`` path (adapt
    :func:`agent_team.nodes.builders_llm.as_diff_builder` into a
    :class:`~agent_team.nodes.builders.DiffBuilder`). Binding it does NOT enable
    any apply/verify behaviour — the BUILD node still only EMITS a diff as DATA
    plus the box-side scan + hash. Held for the gate; not wired here.
    """
    return make_build_node(diff_builder=diff_builder)


def bind_ci_result_fetcher(
    config: VerifierConfig,
    ci_result_fetcher: CiResultFetcher,
) -> Callable[[PipelineState], PipelineState]:
    """Bind the REAL CI-result fetcher into a VERIFY node (GATED-LIVE injection).

    Thin convenience over :func:`make_verify_node` for the leaf that, once the
    §3.3.2 trust boundary clears its security gate, binds the real authenticated
    CI-result fetcher (read-only PAT against the GitHub Checks/Actions API, NOT
    enabled here). The fetcher returns the authenticated conclusion as DATA;
    pass/fail remains owned by the pure-code gate, so binding a fetcher only
    GIVES the gate a result to read — it can never make the LLM the pass
    authority. Held for the gate; not wired here.
    """
    return make_verify_node(config, ci_result_fetcher=ci_result_fetcher)


# A module-level note for the Integrate phase (no execution): the build->verify
# subgraph is hung off the review loop's "build" route. The conditional-edge map
# from VERIFY should send APPROVED_ROUTE to the PR/draft terminus, BUILD_ROUTE
# back to the BUILD node (the bounded build<->verify loop, capped by
# VerifierConfig.max_build_loops), and PARKED_ROUTE to the escalation terminus.
# build_graph wires this in opt-in; this module never assembles it itself.
_INTEGRATE_NOTE = (
    "review('build') -> BUILD -> VERIFY -> route_after_verify -> "
    "{approved: PR terminus, build: BUILD (loop), parked: escalation}"
)