package models

import (
	"crypto/md5"
	"encoding/hex"
	"fmt"
	"sync"
)

type Page struct {
	Data []byte
	ETag string
}

type Cache struct {
	Data map[string]*Page
	Mu   sync.RWMutex
}

func initCache() *Cache {
	return &Cache{Data: make(map[string]*Page)}
}

func (c *Cache) Get(key string) (*Page, bool) {
	c.Mu.RLock()
	page, ok := c.Data[key]
	c.Mu.RUnlock()
	return page, ok
}

func (c *Cache) Set(key string, page *Page) {
	c.Mu.Lock()
	c.Data[key] = page
	c.Mu.Unlock()
}

func GenerateETag(data []byte) string {
	hash := md5.Sum(data)
	return fmt.Sprintf(`"%s"`, hex.EncodeToString(hash[:]))
}