import {Scope} from '../Scope.ts'
import {WhereBuilder} from '../type/WhereBuilder.ts'

/**
 * Base type of functions which provide a query scope.
 */
export type ScopeFunction = (query: WhereBuilder) => WhereBuilder

/**
 * Query scope class which builds its clauses by calling an external function.
 * @extends Scope
 */
export class FunctionScope extends Scope {
    constructor(
        /**
         * The scope function used to scope the query.
         * @type ScopeFunction
         */
        protected _fn: ScopeFunction
    ) {
        super()
    }

    apply(query: WhereBuilder): WhereBuilder {
        return this._fn(query)
    }
}