"""
Agent Replay Promotion Gate
===========================

Final offline gate before an OpenClaw replacement candidate can move toward
production shadow/canary. This gate joins the contract report, scorecard, and
raw candidate metadata so contract probes cannot be mistaken for real evidence.
"""

from __future__ import annotations

from dataclasses import dataclass, field
from typing import Any

from src.services.agent_replacement_evaluator import BASELINE_CANDIDATE_ID


@dataclass(frozen=True)
class AgentReplayPromotionGateReport:
    """Promotion decision for one candidate and one target stage."""

    candidate_id: str
    target_stage: str
    approved: bool
    decision: str
    failures: list[str] = field(default_factory=list)
    evidence: dict[str, Any] = field(default_factory=dict)

    def to_dict(self) -> dict[str, Any]:
        return {
            "schema_version": "agent_replay_promotion_gate_v1",
            "candidate_id": self.candidate_id,
            "target_stage": self.target_stage,
            "approved": self.approved,
            "decision": self.decision,
            "failures": list(self.failures),
            "evidence": dict(self.evidence),
        }


def evaluate_agent_replay_promotion_gate(
    *,
    candidate_id: str,
    scorecard_report: dict[str, Any],
    contract_report: dict[str, Any],
    raw_results: list[dict[str, Any]],
    import_report: dict[str, Any] | None = None,
    target_stage: str = "shadow",
) -> AgentReplayPromotionGateReport:
    """Evaluate whether one candidate may move past offline replay."""
    failures: list[str] = []
    candidate_scorecard = _find_candidate_scorecard(scorecard_report, candidate_id)
    if candidate_id == BASELINE_CANDIDATE_ID:
        failures.append("baseline_candidate_not_promotable")

    _evaluate_contract(candidate_id, contract_report, failures)
    _evaluate_raw_results(candidate_id, raw_results, failures)
    _evaluate_import_report(
        candidate_id,
        import_report,
        contract_report,
        raw_results,
        failures,
    )
    _evaluate_scorecard(candidate_scorecard, failures)

    approved = not failures
    return AgentReplayPromotionGateReport(
        candidate_id=candidate_id,
        target_stage=target_stage,
        approved=approved,
        decision="approved" if approved else "blocked",
        failures=failures,
        evidence=_evidence(
            candidate_scorecard=candidate_scorecard,
            contract_report=contract_report,
            raw_results=raw_results,
            import_report=import_report,
        ),
    )


def _evaluate_contract(
    candidate_id: str,
    contract_report: dict[str, Any],
    failures: list[str],
) -> None:
    if contract_report.get("valid") is not True:
        failures.append("contract_invalid")
    if contract_report.get("candidate_id") != candidate_id:
        failures.append(
            "contract_candidate_mismatch:"
            f"expected={candidate_id};actual={contract_report.get('candidate_id')}"
        )


def _evaluate_raw_results(
    candidate_id: str,
    raw_results: list[dict[str, Any]],
    failures: list[str],
) -> None:
    if not raw_results:
        failures.append("raw_results_empty")
        return

    raw_candidate_ids = {
        str(result.get("candidate_id", "")).strip()
        for result in raw_results
        if str(result.get("candidate_id", "")).strip()
    }
    if raw_candidate_ids != {candidate_id}:
        failures.append(
            "raw_candidate_mismatch:"
            f"expected={candidate_id};actual={','.join(sorted(raw_candidate_ids))}"
        )

    not_evidence = [
        result
        for result in raw_results
        if bool((result.get("metadata") or {}).get("not_replacement_evidence"))
    ]
    if not_evidence:
        failures.append(f"not_replacement_evidence_present:{len(not_evidence)}")

    probes = [
        result
        for result in raw_results
        if (result.get("metadata") or {}).get("adapter_mode") == "contract_probe"
    ]
    if probes:
        failures.append(f"contract_probe_result_present:{len(probes)}")

    errors = [result for result in raw_results if result.get("error")]
    if errors:
        failures.append(f"candidate_result_errors_present:{len(errors)}")


def _evaluate_scorecard(
    candidate_scorecard: dict[str, Any] | None,
    failures: list[str],
) -> None:
    if candidate_scorecard is None:
        failures.append("scorecard_candidate_missing")
        return

    if candidate_scorecard.get("hard_gates_pass") is not True:
        failures.append("scorecard_hard_gates_failed")
    if candidate_scorecard.get("eligible_for_canary") is not True:
        failures.append("scorecard_not_eligible_for_canary")
    if candidate_scorecard.get("beats_baseline") is not True:
        failures.append("candidate_does_not_beat_baseline")

    for failure in candidate_scorecard.get("gate_failures") or []:
        if str(failure).startswith("sample_too_small:"):
            failures.append(str(failure))


def _evaluate_import_report(
    candidate_id: str,
    import_report: dict[str, Any] | None,
    contract_report: dict[str, Any],
    raw_results: list[dict[str, Any]],
    failures: list[str],
) -> None:
    if candidate_id == "nemo_nemotron_fabric" and import_report is None:
        failures.append("nemotron_import_report_missing")
        return
    if import_report is None:
        return

    if import_report.get("valid") is not True:
        failures.append("import_report_invalid")
    if import_report.get("candidate_id") != candidate_id:
        failures.append(
            "import_report_candidate_mismatch:"
            f"expected={candidate_id};actual={import_report.get('candidate_id')}"
        )

    imported_results = int(import_report.get("imported_results") or 0)
    if imported_results != len(raw_results):
        failures.append(
            "import_report_raw_result_count_mismatch:"
            f"imported={imported_results};raw={len(raw_results)}"
        )

    contract_results = int(contract_report.get("results") or 0)
    if contract_results and imported_results != contract_results:
        failures.append(
            "import_report_contract_result_count_mismatch:"
            f"imported={imported_results};contract={contract_results}"
        )

    requests = import_report.get("requests")
    contract_inputs = int(contract_report.get("inputs") or 0)
    if requests is not None and contract_inputs and int(requests) != contract_inputs:
        failures.append(
            "import_report_contract_input_count_mismatch:"
            f"requests={requests};contract={contract_inputs}"
        )

    for key in ("duplicate_results", "missing_results", "unexpected_results"):
        values = list(import_report.get(key) or [])
        if values:
            failures.append(f"import_report_{key}_present:{len(values)}")

    external_errors = int(import_report.get("external_error_records") or 0)
    if external_errors:
        failures.append(f"import_report_external_errors_present:{external_errors}")


def _find_candidate_scorecard(
    scorecard_report: dict[str, Any],
    candidate_id: str,
) -> dict[str, Any] | None:
    for candidate in scorecard_report.get("candidates") or []:
        if candidate.get("candidate_id") == candidate_id:
            return dict(candidate)
    return None


def _evidence(
    *,
    candidate_scorecard: dict[str, Any] | None,
    contract_report: dict[str, Any],
    raw_results: list[dict[str, Any]],
    import_report: dict[str, Any] | None = None,
) -> dict[str, Any]:
    metadata = [dict(result.get("metadata") or {}) for result in raw_results]
    return {
        "contract_valid": bool(contract_report.get("valid")),
        "contract_inputs": int(contract_report.get("inputs") or 0),
        "contract_results": int(contract_report.get("results") or 0),
        "raw_results": len(raw_results),
        "not_replacement_evidence_records": sum(
            1 for item in metadata if item.get("not_replacement_evidence")
        ),
        "contract_probe_records": sum(
            1 for item in metadata if item.get("adapter_mode") == "contract_probe"
        ),
        "candidate_result_error_records": sum(
            1 for result in raw_results if result.get("error")
        ),
        "import_report": _import_report_evidence(import_report),
        "scorecard": _scorecard_evidence(candidate_scorecard),
    }


def _scorecard_evidence(candidate_scorecard: dict[str, Any] | None) -> dict[str, Any]:
    if candidate_scorecard is None:
        return {}
    return {
        "incidents": candidate_scorecard.get("incidents"),
        "total_score": candidate_scorecard.get("total_score"),
        "hard_gates_pass": candidate_scorecard.get("hard_gates_pass"),
        "eligible_for_canary": candidate_scorecard.get("eligible_for_canary"),
        "beats_baseline": candidate_scorecard.get("beats_baseline"),
        "gate_failures": list(candidate_scorecard.get("gate_failures") or []),
    }


def _import_report_evidence(import_report: dict[str, Any] | None) -> dict[str, Any]:
    if import_report is None:
        return {"provided": False}
    return {
        "provided": True,
        "valid": import_report.get("valid"),
        "external_results": import_report.get("external_results"),
        "imported_results": import_report.get("imported_results"),
        "requests": import_report.get("requests"),
        "external_error_records": import_report.get("external_error_records"),
        "fallback_used_records": import_report.get("fallback_used_records"),
        "incomplete_trace_records": import_report.get("incomplete_trace_records"),
        "total_cost_usd": import_report.get("total_cost_usd"),
        "avg_latency_ms": import_report.get("avg_latency_ms"),
        "p95_latency_ms": import_report.get("p95_latency_ms"),
    }