CoreStore/Sources/FetchChainBuilder.swift

//
//  FetchChainBuilder.swift
//  CoreStore
//
//  Copyright © 2018 John Rommel Estropia
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the "Software"), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the Software is
//  furnished to do so, subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included in all
//  copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
//  SOFTWARE.
//

import Foundation
import CoreData


// MARK: - FetchChainBuilder

/**
 The fetch builder type used for fetches. A `FetchChainBuilder` is created from a `From` clause.
 ```
 let people = source.fetchAll(
     From<MyPersonEntity>()
         .where(\.age > 18)
         .orderBy(.ascending(\.age))
 )
 ```
 */
public struct FetchChainBuilder<O: DynamicObject>: FetchChainableBuilderType {
    
    // MARK: FetchChainableBuilderType
    
    public typealias ObjectType = O
    
    public var from: From<O>
    public var fetchClauses: [FetchClause] = []
}


// MARK: - FetchChainableBuilderType

/**
 Utility protocol for `FetchChainBuilder`. Used in fetch methods that support chained fetch builders.
 */
public protocol FetchChainableBuilderType {
    
    /**
     The `DynamicObject` type for the fetch
     */
    associatedtype ObjectType: DynamicObject
    
    /**
     The `From` clause specifies the source entity and source persistent store for the fetch
     */
    var from: From<ObjectType> { get set }
    
    /**
     The `FetchClause`s to be used for the fetch
     */
    var fetchClauses: [FetchClause] { get set }
}