package agent

import (
	"sync"
	"time"
)

// 通用 TTL 缓存：天气结果（*WeatherResult）、CPS 转链（string）等均可复用
type cacheEntry struct {
	data      any
	expiresAt time.Time
}

type Cache struct {
	mu    sync.Mutex
	ttl   time.Duration
	items map[string]cacheEntry
}

func NewTTLCache(ttl time.Duration) *Cache {
	return &Cache{ttl: ttl, items: make(map[string]cacheEntry)}
}

func (c *Cache) Get(key string) (any, bool) {
	c.mu.Lock()
	defer c.mu.Unlock()
	e, ok := c.items[key]
	if !ok {
		return nil, false
	}
	if time.Now().After(e.expiresAt) {
		delete(c.items, key)
		return nil, false
	}
	return e.data, true
}

func (c *Cache) Set(key string, data any) {
	c.mu.Lock()
	defer c.mu.Unlock()
	c.items[key] = cacheEntry{data: data, expiresAt: time.Now().Add(c.ttl)}
}