"""LangSmith trace URL utilities."""

from __future__ import annotations

import logging
import os

logger = logging.getLogger(__name__)


def _compose_langsmith_project_url() -> str:
    """Build the LangSmith project URL base from environment variables."""
    host_url = os.environ.get("LANGSMITH_URL_PROD", "https://smith.langchain.com")
    tenant_id = os.environ.get("LANGSMITH_TENANT_ID_PROD")
    project_id = os.environ.get("LANGSMITH_TRACING_PROJECT_ID_PROD")
    if not tenant_id or not project_id:
        raise ValueError(
            "LANGSMITH_TENANT_ID_PROD and LANGSMITH_TRACING_PROJECT_ID_PROD must be set"
        )
    return f"{host_url}/o/{tenant_id}/projects/p/{project_id}"


def get_langsmith_trace_url(thread_id: str) -> str | None:
    """Build the LangSmith thread URL for a given thread ID."""
    try:
        project_url = _compose_langsmith_project_url()
        return f"{project_url}/t/{thread_id}"
    except Exception:  # noqa: BLE001
        logger.warning(
            "Failed to build LangSmith trace URL for thread %s", thread_id, exc_info=True
        )
        return None