"""模型通道（多通道）配置辅助：默认命名、幂等初始化与默认通道管理。"""
from __future__ import annotations

import os

from sqlalchemy.orm import Session

from models import LlmSetting
from services.llm_client import PROVIDER_PRESETS


def provider_label(provider: str) -> str:
    preset = PROVIDER_PRESETS.get(provider)
    return preset["label"] if preset else provider


def default_channel_name(provider: str, model: str) -> str:
    label = provider_label(provider)
    return f"{label} · {model}" if model else label


def ensure_llm_channels(db: Session) -> None:
    """老库升级：给历史单通道配置补名字并保证存在默认通道。"""
    rows = db.query(LlmSetting).order_by(LlmSetting.id.asc()).all()
    if not rows:
        api_key = os.getenv("OPENAI_API_KEY", "").strip()
        if api_key:
            preset = PROVIDER_PRESETS["openai"]
            db.add(
                LlmSetting(
                    name=default_channel_name("openai", preset["model"]),
                    provider="openai",
                    base_url=preset["base_url"],
                    model=preset["model"],
                    temperature=0.3,
                    api_key=api_key,
                    is_default=True,
                )
            )
            db.commit()
        return
    for row in rows:
        if not row.name:
            row.name = default_channel_name(row.provider, row.model)
    if not any(row.is_default for row in rows):
        rows[0].is_default = True
    db.commit()


def get_default_channel(db: Session) -> LlmSetting | None:
    return (
        db.query(LlmSetting)
        .filter(LlmSetting.is_default.is_(True))
        .order_by(LlmSetting.id.asc())
        .first()
    )


def promote_default(db: Session, channel_id: int | None = None) -> None:
    """把指定通道设为默认；未指定时选择第一个可用通道。"""
    rows = db.query(LlmSetting).order_by(LlmSetting.id.asc()).all()
    for row in rows:
        row.is_default = channel_id is not None and row.id == channel_id
    if channel_id is None and rows:
        rows[0].is_default = True
    db.commit()