/** https://www.zhihu.com/question/68257128?answer_deleted_redirect=true */

function ClassDecorator(path: string) {
    return function (target: Function) {
        !target.prototype.$Meta && (target.prototype.$Meta = {})
        target.prototype.$Meta.baseUrl = path;
        debugger;
    };
}

function MethodDecorator(url: string) {
    return function (target, methodName: string, descriptor: PropertyDescriptor) {
        !target.$Meta && (target.$Meta = {});
        target.$Meta[methodName] = url;
        debugger;
    }
}

function StaticMethodDecorator(url: string) {
    return function (target, methodName: string, descriptor: PropertyDescriptor) {
        debugger;
    }
}

function ParameterDecorator(paramName: string) {
    return function (target, methodName: string, paramIndex: number) {
        !target.$Meta && (target.$Meta = {});
        target.$Meta[paramIndex] = paramName;
        console.log('ParameterDecorator:', paramName);
        debugger;
    }
}

function StaticParameterDecorator(paramName: string) {
    return function (target, methodName: string, paramIndex: number) {
        console.log('StaticParameterDecorator:', paramName);
        debugger;
    }
}

function PropertyDecorator(value: string) {
    //属性描述符不会做为参数传入属性装饰器
    //属性描述符只能用来监视类中是否声明了某个名字的属性。
    return function (target: any, propertyName: string) {
        target[propertyName] = value;
        console.log('PropertyDecorator:', value);
        debugger;
    }
}

function StaticPropertyDecorator(value: number) {
    return function (target: any, propertyName: string) {
        console.log('StaticPropertyDecorator:', value);
        debugger;
    }
}

/**
 * typescript 1.5
 * 装饰器
 * 类、属性、方法、方法参数、getter/setter
 * 执行顺序
 * 1、
 */
@ClassDecorator('/hello')
export class DecoratorExample {
    @PropertyDecorator('hello,world')
    greeting: string;

    @StaticPropertyDecorator(100)
    static hp: number;

    @MethodDecorator("http://www.baidu.com")
    execute( @ParameterDecorator("userId") userId: string, @ParameterDecorator("userId2") userId2: string) {

    }

    @StaticMethodDecorator("http://www.baidu.com")
    static show( @StaticParameterDecorator("userId") userId: string, @StaticParameterDecorator("userId2") userId2: string) {

    }
}

console.log(DecoratorExample.prototype['$Meta']);
console.log(new DecoratorExample().greeting);