# -*- coding: utf-8 -*-
"""
性能优化配置
从 system_settings.json 读取，硬编码值仅作为 fallback
"""
import os
import json
import logging

logger = logging.getLogger(__name__)

# 默认值
_DEFAULTS = {
    "database": {"pool_size": 20, "max_overflow": 30, "pool_recycle": 1800, "pool_timeout": 10},
    "cache": {"default_ttl": 60, "max_memory_size": 2000, "conversation_ttl": 60, "workorder_ttl": 30, "monitoring_ttl": 30},
    "query": {"default_limit": 100, "conversations_limit": 1000, "workorders_limit": 100, "monitoring_limit": 1000},
    "api": {"timeout": 10, "retry_count": 3, "batch_size": 50},
    "monitoring": {"interval": 60, "slow_query_threshold": 1.0, "performance_log_enabled": True}
}

def _load():
    try:
        path = os.path.join('data', 'system_settings.json')
        if os.path.exists(path):
            with open(path, 'r', encoding='utf-8') as f:
                return json.load(f).get('performance', {})
    except Exception as e:
        logger.debug(f"加载性能配置失败: {e}")
    return {}

class PerformanceConfig:
    """性能配置类 — 优先从配置文件读取"""

    @classmethod
    def _get(cls, section, key):
        cfg = _load()
        return cfg.get(section, {}).get(key, _DEFAULTS.get(section, {}).get(key))

    @classmethod
    def get_database_config(cls):
        cfg = _load().get('database', {})
        return {**_DEFAULTS['database'], **cfg}

    @classmethod
    def get_cache_config(cls):
        cfg = _load().get('cache', {})
        return {**_DEFAULTS['cache'], **cfg}

    @classmethod
    def get_query_config(cls):
        cfg = _load().get('query', {})
        return {**_DEFAULTS['query'], **cfg}

    @classmethod
    def get_api_config(cls):
        cfg = _load().get('api', {})
        return {**_DEFAULTS['api'], **cfg}

    # 向后兼容的类属性（读取时动态获取）
    DATABASE_POOL_SIZE = property(lambda self: self._get('database', 'pool_size'))
    CACHE_DEFAULT_TTL = property(lambda self: self._get('cache', 'default_ttl'))
    CACHE_MAX_MEMORY_SIZE = property(lambda self: self._get('cache', 'max_memory_size'))
    QUERY_LIMIT_DEFAULT = property(lambda self: self._get('query', 'default_limit'))
    API_TIMEOUT = property(lambda self: self._get('api', 'timeout'))
    MONITORING_INTERVAL = property(lambda self: self._get('monitoring', 'interval'))