pocka/rusted

import panic from './panic';

import {Trait} from './trait';

import {
    is_empty_function,
    format_static_method_name
} from './util';

let impl=function(/*trait?, target, block*/){
    let trait=arguments[0] instanceof Trait
            ? arguments[0]
            : null ,
        target=trait
            ? arguments[1]
            : arguments[0] ,
        block=trait
            ? arguments[2]
            : arguments[1] ;

    let setter=target.prototype
            ? (name,fn)=>{
                (name[0]==='$')
                    ? (target[format_static_method_name(name)]=fn)
                    : (target.prototype[name]=function(){
                        return fn.apply({},[this].concat(Array.prototype.slice.call(arguments,0)));
                    });
            }
            : panic(`Cannot implementate to ${target}`) ;

    trait
        ? Object.keys(trait).forEach((name)=>{
            block && name in block
                ? setter(name,block[name])
                : (is_empty_function(trait[name])
                    ? panic(`A selected trait needs to implementate method [${name}] !`)
                    : setter(name,trait[name])
                );
        })
        : Object.keys(block).forEach((name)=>{
            setter(name,block[name]);
        });
};

export default impl;