"""Proof-backed reviewer handoff claim verifier (#395).

Reviewer final reports must not claim proof-sensitive workflow steps unless
each claim is backed by explicit command/tool evidence in the transcript or
structured MCP result metadata. This verifier scans report text for the five
proof-sensitive claim families from issue #395 (inventory completeness,
earlier-PR skips, baseline validation, master integration, cleanup) and fails
closed when a claim appears without its required evidence.
"""

from __future__ import annotations

import re
from typing import Any

# Issue #395 criterion 6: reports must distinguish these proof provenances.
PROOF_PROVENANCE_CLASSES = (
    "command actually run",
    "MCP metadata",
    "inherited from previous blocker state",
    "not checked",
)

_INVENTORY_CLAIM_RE = re.compile(
    r"inventory\s+(?:complete|completeness\s*:\s*complete)", re.IGNORECASE
)
_PAGINATION_METADATA_RE = re.compile(
    r"(?:has_more\s*=?\s*false|is_final_page\s*=?\s*true|"
    r"inventory_complete\s*=?\s*true|total[_ ]count\s*[=:]\s*\d+|"
    r"no next page|final page|pagination complete)",
    re.IGNORECASE,
)
_PAGE_SIZE_ASSUMPTION_RE = re.compile(
    r"(?:less|fewer)\s+than\s+(?:the\s+)?(?:default\s+)?page\s*size|"
    r"under\s+the\s+(?:default\s+)?page\s*size|"
    r"below\s+(?:the\s+)?(?:default\s+)?page\s*size",
    re.IGNORECASE,
)

_SKIPPED_PR_RE = re.compile(r"skipped\s+PR\s*#?(\d+)", re.IGNORECASE)
_SKIP_EVIDENCE_RE = re.compile(
    r"(?:mergeable\s*:\s*false|gitea_view_pr|gitea_get_pr_review_feedback|"
    r"gitea_check_pr_eligibility|git\s+merge-tree|merge simulation|"
    r"conflicting files?\s*:|REQUEST_CHANGES\s+at\s+(?:current\s+)?head|"
    r"prior blocker reused|blocker revalidated live)",
    re.IGNORECASE,
)

_BASELINE_CLAIM_RE = re.compile(r"\bbaseline\b", re.IGNORECASE)
_BASELINE_REQUIRED = (
    ("baseline worktree path", re.compile(r"branches/baseline-[\w./-]+", re.IGNORECASE)),
    ("baseline target SHA", re.compile(r"target\s+SHA\s*:?\s*[0-9a-f]{7,40}", re.IGNORECASE)),
    ("baseline dirty-before status", re.compile(r"dirty\s+before\s*:?\s*\w+", re.IGNORECASE)),
    ("exact baseline validation command", re.compile(r"(?:command\s*:|pytest|python\s+-m)", re.IGNORECASE)),
    ("exact baseline result", re.compile(r"(?:result\s*:|passed|failed)", re.IGNORECASE)),
    ("baseline dirty-after status", re.compile(r"dirty\s+after\s*:?\s*\w+", re.IGNORECASE)),
)

_INTEGRATION_CLAIM_RE = re.compile(
    r"(?:master\s+(?:was\s+)?(?:merged|rebased|integrated)|"
    r"merged?\s+master\s+into|master[- ]integration|rebased\s+onto\s+master)",
    re.IGNORECASE,
)
_INTEGRATION_EVIDENCE_RE = re.compile(
    r"(?:git\s+merge(?:\s+--no-commit|\s+--no-ff)?|git\s+rebase|git\s+merge-tree)",
    re.IGNORECASE,
)

_CLEANUP_CLAIM_RE = re.compile(
    r"worktrees?\s+(?:were\s+)?(?:removed|cleaned|deleted)|"
    r"cleanup\s*:\s*(?!none)\S",
    re.IGNORECASE,
)
_CLEANUP_EVIDENCE_RE = re.compile(r"git\s+worktree\s+list", re.IGNORECASE)


def assess_proof_backed_handoff_report(report_text: str) -> dict[str, Any]:
    """Fail closed on proof-sensitive claims that lack explicit evidence (#395)."""
    text = report_text or ""
    reasons: list[str] = []

    if _INVENTORY_CLAIM_RE.search(text):
        if _PAGE_SIZE_ASSUMPTION_RE.search(text):
            reasons.append(
                "inventory completeness claimed from a page size assumption; "
                "explicit pagination metadata (has_more=false / is_final_page=true / "
                "inventory_complete=true / total count) is required"
            )
        elif not _PAGINATION_METADATA_RE.search(text):
            reasons.append(
                "inventory completeness claimed without explicit pagination "
                "metadata proof (has_more=false, is_final_page=true, "
                "inventory_complete=true, or total count)"
            )

    for match in _SKIPPED_PR_RE.finditer(text):
        pr_number = match.group(1)
        window = text[match.start():match.start() + 400]
        if not _SKIP_EVIDENCE_RE.search(window):
            reasons.append(
                f"skipped PR #{pr_number} claim has no explicit command/tool "
                "proof or structured mergeability/blocker evidence"
            )

    if _BASELINE_CLAIM_RE.search(text):
        missing = [
            name for name, pattern in _BASELINE_REQUIRED if not pattern.search(text)
        ]
        if missing:
            reasons.append(
                "baseline validation claim missing required proof fields: "
                + ", ".join(missing)
            )

    if _INTEGRATION_CLAIM_RE.search(text) and not _INTEGRATION_EVIDENCE_RE.search(text):
        reasons.append(
            "master-integration claim lacks the exact merge/rebase/simulation "
            "command and result"
        )

    if _CLEANUP_CLAIM_RE.search(text) and not _CLEANUP_EVIDENCE_RE.search(text):
        reasons.append(
            "cleanup claim lacks final `git worktree list` (or equivalent) proof "
            "that session-owned worktrees were removed"
        )

    return {
        "proven": not reasons,
        "block": bool(reasons),
        "reasons": reasons,
        "provenance_classes": PROOF_PROVENANCE_CLASSES,
    }