"""定制简历 Redis 存取模块

提供定制简历的保存（自动回滚备份）、查询、回滚能力。
各 Service 统一复用，不直接操作 Redis key。
"""

from app.core.redis import RedisManager
from app.schemas.customize_resume import CustomizeResume

# Redis 常量
KEY_PREFIX = "customize:resume:"
EXPIRE = 12 * 60 * 60  # 12小时
ROLLBACK_KEY_PREFIX = "customize:resume:rollback:"
ROLLBACK_EXPIRE = 30 * 60  # 30分钟


async def save(user_id: int, cr: CustomizeResume) -> None:
    """保存定制简历，自动备份旧版本到回滚 key"""
    key = f"{KEY_PREFIX}{user_id}"
    rollback_key = f"{ROLLBACK_KEY_PREFIX}{user_id}"
    # 备份旧数据
    old_data = await RedisManager.client.get(key)
    if old_data:
        await RedisManager.client.set(rollback_key, old_data, ex=ROLLBACK_EXPIRE)
    # 存新数据
    await RedisManager.client.set(key, cr.model_dump_json(by_alias=True), ex=EXPIRE)


async def get(user_id: int) -> dict | None:
    """查询定制简历，返回 dict 或 None"""
    key = f"{KEY_PREFIX}{user_id}"
    data = await RedisManager.client.get(key)
    if data:
        return CustomizeResume.model_validate_json(data).model_dump(by_alias=True)
    return None


async def rollback(user_id: int) -> None:
    """回滚定制简历到上一版本"""
    rollback_key = f"{ROLLBACK_KEY_PREFIX}{user_id}"
    data = await RedisManager.client.get(rollback_key)
    if not data:
        raise ValueError("没有可回滚的版本")
    key = f"{KEY_PREFIX}{user_id}"
    await RedisManager.client.set(key, data, ex=EXPIRE)
    await RedisManager.client.delete(rollback_key)