# ============================================================
# 长任务进度 / Thinking 日志（moduleId: core-progress, 可重生 ✅）
# 同步代码 emit → 网关 SSE 轮询 drain → 前端 Thinking 面板
# ============================================================
from __future__ import annotations

import threading
import time
from collections import deque
from typing import Any

_lock = threading.Lock()
_buf: deque[dict[str, Any]] = deque(maxlen=200)
_active = False


def begin_progress() -> None:
    """一轮对话开始：清空缓冲并启用（跨线程可见）。"""
    global _active
    with _lock:
        _buf.clear()
        _active = True


def end_progress() -> None:
    global _active
    with _lock:
        _active = False


def emit_thinking(
    step: str,
    detail: str = "",
    *,
    status: str = "running",
    pct: float | None = None,
) -> None:
    """推送一条 Thinking 步骤（线程安全，供 SQL 扫描等后台线程调用）。"""
    with _lock:
        if not _active:
            return
        ev: dict[str, Any] = {
            "type": "thinking",
            "step": step,
            "detail": detail or "",
            "status": status,  # running | done | warn
            "ts": time.time(),
        }
        if pct is not None:
            ev["pct"] = max(0.0, min(100.0, float(pct)))
        _buf.append(ev)


def drain_thinking() -> list[dict[str, Any]]:
    """取出并清空当前缓冲。"""
    with _lock:
        items = list(_buf)
        _buf.clear()
        return items