export interface Constructor<T = {}> {
    new(...args: any[]): T;
}

export type MixinFunc<TBase, MCls> = (baseClass: TBase) => TBase & MCls;
export type MixinType<M extends MixinFunc<any, any>> = InstanceType<ReturnType<M>>

export const mix = <T extends Constructor>(superclass?: T): MixinBuilder<T> => new MixinBuilder(superclass);

export function MixClasses<A1, A2, A3, A4, A5, A6, A7>(A1: Constructor<A1>, A2?: Constructor<A2>, A3?: Constructor<A3>, A4?: Constructor<A4>, A5?: Constructor<A5>, A6?: Constructor<A6>, A7?: Constructor<A7>):
    Constructor<A1 & A2 & A3 & A4 & A5 & A6 & A7> {

    const mixins = [...arguments];
    class MixedClass {
        constructor() {
            for (let cls of mixins) {
                Object.assign(this, new cls());
            }
        }
    }
    for (let mixin of mixins) {
        for (let [key, desc] of Object.entries(Object.getOwnPropertyDescriptors(mixin.prototype))) {
            if (key == 'constructor') continue;
            Object.defineProperty(MixedClass.prototype, key, desc);
        }
    }
    return MixedClass as any;
}

// export function Mix<TBase extends Constructor, A1, A2, A3, A4, A5, A6, A7>(arg1: TBase, A1?: MixinFunc<TBase, A1>, A2?: MixinFunc<TBase, A2>, A3?: MixinFunc<TBase, A3>, A4?: MixinFunc<TBase, A4>, A5?: MixinFunc<TBase, A5>, A6?: MixinFunc<TBase, A6>, A7?: MixinFunc<TBase, A7>): (A1 & A2 & A3 & A4 & A5 & A6 & A7) & TBase {
// 	const [base, ...args] = arguments;
// 	return [...args].reduce((c, mixin) => mixin(c), base);
// }

class RootClass { }

class MixinBuilder<TBase extends Constructor> {
    constructor(superclass: TBase) {
        this.superclass = superclass || RootClass as any;
    }

    superclass: TBase;

    with<A1, A2, A3, A4, A5, A6, A7>(A1?: MixinFunc<TBase, A1>, A2?: MixinFunc<TBase, A2>, A3?: MixinFunc<TBase, A3>, A4?: MixinFunc<TBase, A4>, A5?: MixinFunc<TBase, A5>, A6?: MixinFunc<TBase, A6>, A7?: MixinFunc<TBase, A7>): (A1 & A2 & A3 & A4 & A5 & A6 & A7) & TBase {
        return [...arguments].reduce((c, mixin) => mixin(c), this.superclass);
    }
}

export default mix;