import {Canonical, CanonicalDefinition} from './Canonical'
import {isStaticClass, StaticClass} from '../di'
import {InvalidCanonicalExportError} from './CanonicalInstantiable'

/**
 * Variant of the Canonical unit whose files export static classes, and these static classes
 * are the exports of the class.
 *
 * @example
 * The Controllers class is CanonicalStatic. The various `.controller.ts` files export static
 * Controller classes, so the canonical items managed by the Controllers service are `Instantiable<Controller>`.
 */
export class CanonicalStatic<T, T2> extends Canonical<StaticClass<T, T2>> {
    public async initCanonicalItem(definition: CanonicalDefinition): Promise<StaticClass<T, T2>> {
        if ( isStaticClass(definition.imported.default) ) {
            return definition.imported.default
        }

        if ( isStaticClass(definition.imported[definition.canonicalName.split(':').reverse()[0]]) ) {
            return definition.imported[definition.canonicalName.split(':').reverse()[0]]
        }

        throw new InvalidCanonicalExportError(definition.originalName)
    }
}