import {AbstractFactory} from './AbstractFactory'
import {DependencyKey, DependencyRequirement, PropertyDependency} from '../types'
import {Collection} from '../../util'

/**
 * A factory whose token is produced by calling a function.
 *
 * @example
 * ```typescript
 * let i = 0
 * const fact = new ClosureFactory('someName', () => {
 *     i += 1
 *     return i * 2
 * })
 *
 * fact.produce([], [])  // => 2
 * fact.produce([], [])  // => 4
 * ```
 */
export class ClosureFactory<T> extends AbstractFactory<T> {
    constructor(
        protected readonly name: DependencyKey,
        protected readonly token: () => T,
    ) {
        super(token)
    }

    produce(): any {
        return this.token()
    }

    match(something: unknown): boolean {
        return something === this.name
    }

    getDependencyKeys(): Collection<DependencyRequirement> {
        return new Collection<DependencyRequirement>()
    }

    getInjectedProperties(): Collection<PropertyDependency> {
        return new Collection<PropertyDependency>()
    }
}