"""Output gate — classifies content as system/internal vs public-facing.

Blocks pipeline messages (extraction logs, merge notifications, diagnostics)
from ever reaching the tweet queue or any public-facing output.

This is a deterministic classifier — no LLM calls. Pattern matching on content.

Epimetheus owns this module.
"""

import re

# ─── System Message Patterns ─────────────────────────────────────────
# Content matching ANY of these is classified as system/internal.

_SYSTEM_PATTERNS = [
    # Pipeline operations
    re.compile(r"\b(PR\s*#\d+|pull request|merge|rebase|cherry.?pick)\b", re.IGNORECASE),
    re.compile(r"\b(extraction|extracted|extractor|extract/)\b", re.IGNORECASE),
    re.compile(r"\b(pipeline|cron|batch.?extract|systemd|teleo-pipeline)\b", re.IGNORECASE),
    re.compile(r"\b(conflict.?permanent|conflict.?closed|merge.?conflict)\b", re.IGNORECASE),

    # Infrastructure / ops
    re.compile(r"\b(schema\s*v\d+|migration\s*v\d+|SCHEMA_VERSION)\b", re.IGNORECASE),
    re.compile(r"\b(deploy|VPS|ssh|scp|systemctl|journalctl)\b", re.IGNORECASE),
    re.compile(r"\b(Qdrant|embed.?on.?merge|vector.?gc|backfill)\b", re.IGNORECASE),
    re.compile(r"\b(ReadWritePaths|ProtectSystem|ExecStartPre)\b", re.IGNORECASE),

    # Diagnostics
    re.compile(r"\b(vital.?signs|queue.?staleness|orphan.?ratio)\b", re.IGNORECASE),
    re.compile(r"\b(approval.?rate|throughput|PRs?.?per.?hour)\b", re.IGNORECASE),
    re.compile(r"\b(reviewer_count|reviewer.?backfill)\b", re.IGNORECASE),

    # Agent coordination internals
    re.compile(r"\b(Ganymede|Rhea|Oberon)\s+(review(?:ed)?|approv(?:ed|es?)|reject(?:ed|s)?)\b", re.IGNORECASE),
    re.compile(r"\b(PIPELINE_OWNED_PREFIXES|AGENT_NAMES)\b"),
    re.compile(r"\b(worktree|bare.?repo|forgejo|git\.livingip)\b", re.IGNORECASE),

    # Code / technical
    re.compile(r"\b(def\s+\w+|import\s+\w+|class\s+\w+)\b"),
    re.compile(r"\b(\.py|\.yaml|\.json|\.md)\s", re.IGNORECASE),
    re.compile(r"\b(sqlite3?|pipeline\.db|response_audit)\b", re.IGNORECASE),

    # Internal metrics / debugging
    re.compile(r"\b(cosine.?sim|threshold|PRIOR_ART_THRESHOLD)\b", re.IGNORECASE),
    re.compile(r"\b(pre.?screen|Layer\s*[01234]|RRF|entity.?boost)\b", re.IGNORECASE),

    # Paths
    re.compile(r"/opt/teleo-eval/"),
    re.compile(r"/Users/\w+/"),
    re.compile(r"\.pentagon/"),
]

# ─── Public Content Signals ──────────────────────────────────────────
# Content matching these is MORE LIKELY to be public-facing.
# These don't override system classification — they're tiebreakers.

_PUBLIC_SIGNALS = [
    re.compile(r"^(thread|tweet|post):", re.IGNORECASE | re.MULTILINE),
    re.compile(r"\b(insight|analysis|take|perspective|argument)\b", re.IGNORECASE),
    re.compile(r"\b(audience|followers|engagement|impression)\b", re.IGNORECASE),
]


class GateResult:
    """Result of output gate classification."""

    __slots__ = ("is_public", "blocked_reasons", "confidence")

    def __init__(self, is_public: bool, blocked_reasons: list[str], confidence: float):
        self.is_public = is_public
        self.blocked_reasons = blocked_reasons
        self.confidence = confidence

    def __bool__(self):
        return self.is_public

    def __repr__(self):
        status = "PUBLIC" if self.is_public else "BLOCKED"
        return f"GateResult({status}, reasons={self.blocked_reasons}, conf={self.confidence:.2f})"


def classify(content: str) -> GateResult:
    """Classify content as public-facing or system/internal.

    Returns GateResult:
    - is_public=True: safe for tweet queue / public output
    - is_public=False: system content, blocked from public outputs
    """
    if not content or not content.strip():
        return GateResult(False, ["empty content"], 1.0)

    # Count system pattern matches
    system_hits = []
    for pattern in _SYSTEM_PATTERNS:
        match = pattern.search(content)
        if match:
            system_hits.append(match.group())

    # Count public signals
    public_hits = sum(1 for p in _PUBLIC_SIGNALS if p.search(content))

    # Decision logic
    if len(system_hits) >= 3:
        # Strong system signal — definitely internal
        return GateResult(False, system_hits[:5], 0.95)

    if len(system_hits) >= 1 and public_hits == 0:
        # Some system signal, no public signal — likely internal
        return GateResult(False, system_hits, 0.75)

    if len(system_hits) == 0:
        # No system signal — public
        return GateResult(True, [], 0.90 if public_hits > 0 else 0.70)

    # Mixed signals (system hits + public signals) — default to blocking
    # Better to block a borderline tweet than leak system info
    return GateResult(False, system_hits, 0.50)


def gate_for_tweet_queue(content: str, agent: str = None) -> GateResult:
    """Gate specifically for the tweet queue. Stricter than general classify.

    Additional checks:
    - OPSEC filter (imported from approvals)
    - Agent attribution check
    """
    result = classify(content)
    if not result.is_public:
        return result

    # Additional tweet-specific checks
    blocked = []

    # Must not be too short (probably a fragment or command)
    stripped = content.strip()
    if len(stripped) < 20:
        blocked.append("content too short for tweet (<20 chars)")

    # Must not contain raw URLs to internal systems
    if re.search(r"https?://(?:localhost|127\.0\.0\.1|77\.42\.65\.182)", stripped):
        blocked.append("contains internal URL")

    if blocked:
        return GateResult(False, blocked, 0.85)

    return result