var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var ObjectId = Schema.ObjectId;
  
/*
 * type:
 * reply: xx 回复了你的话题
 * reply2: xx 在话题中回复了你
 * follow: xx 关注了你
 * at: xx ＠了你
 */
 
var MessageSchema = new Schema({
  type: { type: String },
  master_id: { type: ObjectId, index: true },
  author_id: { type: ObjectId },
  topic_id: { type: ObjectId },
  reply_id: { type: ObjectId },
  has_read: { type: Boolean, default: false },
  create_at: { type: Date, default: Date.now }
});

mongoose.model('Message', MessageSchema);
