WIP: Query builders

Sources/FetchCondition.swift

@@ -0,0 +1,143 @@
+//
+//  FetchCondition.swift
+//  CoreStore
+//
+//  Copyright © 2017 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
+
+public struct ChainedClauseBuilder<T: DynamicObject> {
+    
+    public let from: From<T>
+    public let fetchClauses: [FetchClause] = []
+    
+    internal init(from: From<T>) {
+        
+        self.from = from
+    }
+}
+
+extension From: ClauseChain {
+    
+    public typealias ObjectType = T
+    public typealias TraitType = FetchTrait
+    
+    public var builder: ChainedClauseBuilder<T> {
+        
+        return .init(from: self)
+    }
+}
+
+public struct ChainedWhere<D: DynamicObject, T: ClauseTrait>: ClauseChain {
+    
+    public typealias ObjectType = D
+    public typealias TraitType = T
+    
+    public let builder: ChainedClauseBuilder<ObjectType>
+    
+    fileprivate init(builder: ChainedClauseBuilder<ObjectType>) {
+        
+        var newBuilder = builder
+//        newBuilder.fetchClauses.append(Where())
+        self.builder = newBuilder
+    }
+}
+
+public struct ChainedOrderBy<D: DynamicObject, T: ClauseTrait>: ClauseChain {
+    
+    public typealias ObjectType = D
+    public typealias TraitType = T
+    
+    public let builder: ChainedClauseBuilder<ObjectType>
+    
+    fileprivate init(builder: ChainedClauseBuilder<ObjectType>) {
+        
+        var newBuilder = builder
+//        newBuilder.fetchClauses.append(Where())
+        self.builder = newBuilder
+    }
+}
+
+public struct ChainedSelect<D: DynamicObject, T: ClauseTrait>: ClauseChain {
+    
+    public typealias ObjectType = D
+    public typealias TraitType = T
+    
+    public let builder: ChainedClauseBuilder<ObjectType>
+    
+    fileprivate init(builder: ChainedClauseBuilder<ObjectType>) {
+        
+        var newBuilder = builder
+//        newBuilder.fetchClauses.append(Where())
+        self.builder = newBuilder
+    }
+}
+
+
+
+
+
+public protocol ClauseTrait {}
+public enum FetchTrait: ClauseTrait {}
+public enum QueryTrait: ClauseTrait {}
+public enum SectionTrait: ClauseTrait {}
+
+
+public protocol ClauseChain {
+    
+    associatedtype ObjectType: DynamicObject
+    associatedtype TraitType: ClauseTrait
+    
+    var builder: ChainedClauseBuilder<ObjectType> { get }
+}
+
+public extension ClauseChain where Self.TraitType == FetchTrait {
+    
+    public func `where`() -> ChainedWhere<ObjectType, FetchTrait> {
+        
+        return .init(builder: self.builder)
+    }
+    
+    public func orderBy() -> ChainedOrderBy<ObjectType, FetchTrait> {
+        
+        return .init(builder: self.builder)
+    }
+    
+    public func select() -> ChainedSelect<ObjectType, QueryTrait> {
+        
+        return .init(builder: self.builder)
+    }
+}
+
+public extension ClauseChain where Self.TraitType == QueryTrait {
+    
+    public func `where`() -> ChainedWhere<ObjectType, QueryTrait> {
+        
+        return .init(builder: self.builder)
+    }
+    
+    public func orderBy() -> ChainedOrderBy<ObjectType, QueryTrait> {
+        
+        return .init(builder: self.builder)
+    }
+}