"""Decide whether external messages should be mirrored into a Human Handoff thread."""

MESSAGE_SCOPE_EXTERNAL = "EXTERNAL"

# Message provenance — who authored / generated the content
MESSAGE_ORIGIN_EXTERNAL_CUSTOMER = "EXTERNAL_CUSTOMER"
MESSAGE_ORIGIN_HUMAN_OWNER = "HUMAN_OWNER"
MESSAGE_ORIGIN_AGENT = "AGENT"
MESSAGE_ORIGIN_SYSTEM = "SYSTEM"
MESSAGE_ORIGIN_HANDOFF_MIRROR = "HANDOFF_MIRROR"

GENERATED_BY_CUSTOMER = "CUSTOMER"
GENERATED_BY_HUMAN = "HUMAN"
GENERATED_BY_AGENT = "AGENT"
GENERATED_BY_HANDOFF_BRIDGE = "HANDOFF_BRIDGE"
GENERATED_BY_SYSTEM = "SYSTEM"
GENERATED_BY_RELAY_ACK = "RELAY_ACK"

RELAY_STATUS_SENT = "SENT"
RELAY_STATUS_FAILED = "FAILED"
RELAY_STATUS_PENDING = "PENDING"
RELAY_STATUS_BLOCKED = "BLOCKED"


def should_mirror_to_human(message: dict) -> bool:
    """Return True only for new external customer content worth mirroring."""
    scope = message.get("message_scope", MESSAGE_SCOPE_EXTERNAL)
    if scope != MESSAGE_SCOPE_EXTERNAL:
        return False

    if message.get("direction") not in ("inbound", "outbound"):
        return False

    generated_by = message.get("generated_by")
    if generated_by in (
        GENERATED_BY_HANDOFF_BRIDGE,
        GENERATED_BY_RELAY_ACK,
        GENERATED_BY_SYSTEM,
    ):
        return False

    origin = message.get("message_origin")
    if origin in (
        MESSAGE_ORIGIN_HUMAN_OWNER,
        MESSAGE_ORIGIN_SYSTEM,
        MESSAGE_ORIGIN_HANDOFF_MIRROR,
    ):
        return False

    if message.get("generated_from_handoff_message_id"):
        return False

    if message.get("direction") == "outbound":
        return (
            generated_by == GENERATED_BY_AGENT
            or origin == MESSAGE_ORIGIN_AGENT
        )
    return True


def is_relay_acknowledgment_message(message: dict) -> bool:
    """Detect legacy or internal delivery-receipt messages in handoff threads."""
    if message.get("generated_by") == GENERATED_BY_RELAY_ACK:
        return True
    if message.get("message_origin") == MESSAGE_ORIGIN_SYSTEM:
        return True
    body = (message.get("body_text") or message.get("snippet") or "").strip()
    return message.get("direction") == "outbound" and body.startswith("Sent to customer")