"""SSE / replay envelope. Wire names are camelCase; payloads stay snake_case."""

from __future__ import annotations

from typing import Any

from pydantic import BaseModel, ConfigDict, Field

from app.report_collaboration.contracts.enums import CollaborationEventType


class CollaborationEventEnvelope(BaseModel):
    """Durable event envelope consumed by the frontend reducer."""

    model_config = ConfigDict(extra="forbid", populate_by_name=True)

    event_id: str = Field(alias="eventId")
    session_id: str = Field(alias="sessionId")
    run_id: str | None = Field(default=None, alias="runId")
    seq: int = Field(ge=1)
    type: CollaborationEventType
    timestamp: str
    data: dict[str, Any] = Field(default_factory=dict)

    def to_sse_dict(self) -> dict[str, Any]:
        return self.model_dump(by_alias=True, exclude_none=False)