const Sequelize=require('sequelize');
const uuid=require('node-uuid');
const config=require('./config');
console.log('init sequelize...');
function generateId(){
    return uuid.v4();    
};
var sequelize=new Sequelize(config.database,config.username,config.password,{
    host:config.host,
    dialect:config.dialect,
    pool:{
        max:5,
        min:0,
        idle:10000    
    }
});
const ID_TYPE=Sequelize.STRING(50);
function defineModel(name,attributes){
    var attrs={};
    for(let key in attributes){
        let value=attributes[key];
        if(typeof value==='object'&&value['type']){
            value.allowNull=value.allowNull||false;
            attrs[key]=value;
        }else{
            attrs[key]={
                type:value,
                allowNull:false    
            };
        }
    }
    
    attrs.id={
        type:ID_TYPE,
        primaryKey:true
    };
    attrs.createAt={
        type:Sequelize.BIGINT,
        allowNull:false    
    };
    attrs.updateAt={
        type:Sequelize.BIGINT,
        allowNull:false    
    };
    attrs.version={
        type:Sequelize.BIGINT,
        allowNull:false   
    };
    return sequelize.define(name,attrs,{
        tableName:name,
        timestamps:false,
        hooks:{
            beforeValidate:obj=>{
                let now=Date.now();
                if(obj.isNewRecord){
                    if(!obj.id){
                        obj.id=generateId();    
                    }
                    obj.createAt=now;
                    obj.updateAt=now;
                    obj.version=0;        
                }else{
                    obj.updateAt=Date.now();
                    obj.version++;    
                }    
            }    
        }    
    });
}
var exp={
    defineModel:defineModel,
    sync:()=>{
        if(process.env.NODE_ENV!=='production'){
            sequelize.sync({force:true});    
        }else{
            throw new Error('Cannot sync() when NODE_ENV is set to \'production\'')
        }    
    }    
};
const TYPES=['STRING','INTEGER','BIGINT','TEXT','DOUBLE','DATEONLY','BOOLEAN'];
for(let type of TYPES){
    exp[type]=Sequelize[type];    
};
exp.ID=ID_TYPE;
exp.generateId=generateId;
module.exports=exp;