using System;
using System.Web;
using System.Web.Caching;
using System.Collections;

namespace WebApplication1
{
 /// <summary>
 /// 緩存的類型，他們之間是否是包含關(guān)系？
 /// </summary>
 public enum CoreCacheType
 {
  Host = 1,
  Portal,
  Tab
 }

 /// <summary>
 /// 對系統(tǒng)緩存的操作
 /// </summary>
 public class DataCache
 {
  public DataCache()
  {
   //
   // TODO: 在此處添加構(gòu)造函數(shù)邏輯
   //
  }

  /// <summary>
  /// 取得某緩存的值
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  /// <returns>緩存的值</returns>
  public static object GetCache(string CacheKey)
  {
   // HttpRuntime.Cache：獲取當(dāng)前應(yīng)用程序的 System.Web.Caching.Cache。
   // System.Web.Caching.Cache：實(shí)現(xiàn)用于 Web 應(yīng)用程序的緩存。
   Cache objCache = HttpRuntime.Cache;
   return objCache[CacheKey];
  }

  /// <summary>
  /// 設(shè)置某緩存的值。
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  /// <param name="objObject">緩存的值</param>
  public static void SetCache(string CacheKey, object objObject)
  {
   Cache objCache = HttpRuntime.Cache;
   objCache.Insert(CacheKey, objObject);
  }

  /// <summary>
  /// 設(shè)置某緩存的值和跟蹤緩存依賴項(xiàng)。
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  /// <param name="objObject">緩存的值</param>
  /// <param name="objDependency">緩存依賴項(xiàng)</param>
  public static void SetCache(string CacheKey, object objObject, CacheDependency objDependency)
  {
   Cache objCache = HttpRuntime.Cache;
   objCache.Insert(CacheKey, objObject, objDependency);
  }

  /// <summary>
  /// 設(shè)置某緩存的值和跟蹤緩存依賴項(xiàng)。
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  /// <param name="objObject">緩存的值</param>
  /// <param name="objDependency">緩存依賴項(xiàng)</param>
  /// <param name="AbsoluteExpiration">緩存移出的時(shí)間</param>
  /// <param name="SlidingExpiration">緩存的有效期時(shí)間長度</param>
  public static void SetCache(string CacheKey, object objObject, CacheDependency objDependency, DateTime AbsoluteExpiration, TimeSpan SlidingExpiration)
  {
   Cache objCache = HttpRuntime.Cache;
   objCache.Insert(CacheKey, objObject, objDependency, AbsoluteExpiration, SlidingExpiration);
  }

  /// <summary>
  /// 設(shè)置某緩存的值。
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  /// <param name="objObject">緩存的值</param>
  /// <param name="SlidingExpiration">緩存的有效期時(shí)間長度</param>
  public static void SetCache(string CacheKey, object objObject, TimeSpan SlidingExpiration)
  {
   Cache objCache = HttpRuntime.Cache;
   objCache.Insert(CacheKey, objObject, null, Cache.NoAbsoluteExpiration, SlidingExpiration);
  }

  /// <summary>
  ///  設(shè)置某緩存的值。
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  /// <param name="objObject">緩存的值</param>
  /// <param name="AbsoluteExpiration">緩存移出的時(shí)間</param>
  public static void SetCache(string CacheKey, object objObject, DateTime AbsoluteExpiration)
  {
   Cache objCache = HttpRuntime.Cache;
   objCache.Insert(CacheKey, objObject, null, AbsoluteExpiration, Cache.NoSlidingExpiration);
  }

  /// <summary>
  /// 從緩存中移出某鍵的緩存值
  /// </summary>
  /// <param name="CacheKey">緩存的鍵</param>
  public static void RemoveCache(string CacheKey)
  {
   Cache objCache = HttpRuntime.Cache;
   if (objCache[CacheKey] != null)
   {
    objCache.Remove(CacheKey);
   }
  }

  public static void ClearCoreCache(CoreCacheType Type, int ID, bool Cascade)
  {
   switch (Type)
   {
     // 清除Host緩存
    case CoreCacheType.Host:
     ClearHostCache(Cascade);
     break;
     // 清除Portal緩存
    case CoreCacheType.Portal:
     ClearPortalCache(ID, Cascade);
     break;
     // 清除Tab緩存
    case CoreCacheType.Tab:
     ClearTabCache(ID);
     break;
    default:
     break;
   }
  }

  /// <summary>
  /// 清除Host緩存。
  /// </summary>
  /// <param name="Cascade"></param>
  private static void ClearHostCache(bool Cascade)
  {
   Cache objCache = HttpRuntime.Cache;

   if (objCache["GetHostSettings"] != null)
   {
    objCache.Remove("GetHostSettings");
   }

   if (objCache["GetPortalByAlias"] != null)
   {
    objCache.Remove("GetPortalByAlias");
   }

   if (objCache["CSS"] != null)
   {
    objCache.Remove("CSS");
   }

   if (Cascade)
   {
    PortalController objPortals = new PortalController();

    // 在這里聲明PortalInfo，是為了提高效率考慮。
    PortalInfo objPortal;

    // 取得一個(gè)PortalInfo集合
    ArrayList arrPortals = objPortals.GetPortals();

    for (int intIndex = 0; intIndex < arrPortals.Count; intIndex++)
    {
     objPortal = (PortalInfo)arrPortals[intIndex];

     // 清除Portal緩存
     ClearPortalCache(objPortal.PortalID, Cascade);
    }
   }
  }

  /// <summary>
  /// 清除Portal緩存。
  /// </summary>
  /// <param name="PortalId"></param>
  /// <param name="Cascade"></param>
  private static void ClearPortalCache(int PortalId, bool Cascade)
  {
   Cache objCache = HttpRuntime.Cache;

   if (objCache["GetPortalSettings" + PortalId] != null)
   {
    objCache.Remove("GetPortalSettings" + PortalId);
   }

   if (objCache["GetTabs" + PortalId] != null)
   {
    objCache.Remove("GetTabs" + PortalId);
   }

   if (Cascade)
   {
    TabController objTabs = new TabController();
    TabInfo objTab;

    // 取得TabInfo集合
    ArrayList arrTabs = objTabs.GetTabs(PortalId);

    for (int intIndex = 0; intIndex < arrTabs.Count; intIndex++)
    {
     objTab = (TabInfo)arrTabs[intIndex];

     // 移除Tab緩存
     ClearTabCache(objTab.TabID);
    }
   }
  }

  /// <summary>
  /// 清除Tab緩存。
  /// </summary>
  /// <param name="TabId"></param>
  private static void ClearTabCache(int TabId)
  {
   Cache objCache = HttpRuntime.Cache;

   if (objCache["GetTab" + TabId] != null)
   {
    objCache.Remove("GetTab" + TabId);
   }

   if (objCache["GetPortalTabModules" + TabId] != null)
   {
    objCache.Remove("GetPortalTabModules" + TabId);
   }

   TabController objTabs = new TabController();

   // 取得TabInfo對象
   TabInfo objTab = objTabs.GetTab(TabId);

   if (objTab != null)
   {
    if (objCache["GetTabPermissionsByPortal" + objTab.PortalID] != null)
    {
     objCache.Remove("GetTabPermissionsByPortal" + objTab.PortalID);
    }
   }
  }

 }
}