semantic/prototype/Doubt/JSON.swift

public enum JSON: ArrayLiteralConvertible, BooleanLiteralConvertible, DictionaryLiteralConvertible, Equatable, FloatLiteralConvertible, IntegerLiteralConvertible, JSONConvertible, NilLiteralConvertible, StringLiteralConvertible {
	public typealias ArrayType = [Doubt.JSON]
	public typealias DictionaryType = [Swift.String:Doubt.JSON]

	case Number(Double)
	case Boolean(Bool)
	case String(Swift.String)
	case Array(ArrayType)
	case Dictionary(DictionaryType)
	case Null


	public init(_ convertible: CustomJSONConvertible) {
		self = convertible.JSON
	}


	public var number: Double? {
		if case let .Number(d) = self { return d }
		return nil
	}

	public var boolean: Bool? {
		if case let .Boolean(b) = self { return b }
		return nil
	}

	public var string: Swift.String? {
		if case let .String(s) = self { return s }
		return nil
	}

	public var array: ArrayType? {
		if case let .Array(a) = self { return a }
		return nil
	}

	public var dictionary: DictionaryType? {
		if case let .Dictionary(d) = self { return d }
		return nil
	}

	public var isNull: Bool {
		if case .Null = self { return true }
		return false
	}

	public init?(object: AnyObject) {
		struct E: ErrorType {}
		func die<T>() throws -> T {
			throw E()
		}
		do {
			switch object {
			case let n as Double:
				self = .Number(n)
			case let b as Bool:
				self = .Boolean(b)
			case let s as Swift.String:
				self = .String(s)
			case let a as [AnyObject]:
				self = .Array(try a.map { try Doubt.JSON(object: $0) ?? die() })
			case let d as [Swift.String:AnyObject]:
				self = .Dictionary(Swift.Dictionary(elements: try d.map { ($0, try Doubt.JSON(object: $1) ?? die()) }))
			case is NSNull:
				self = .Null
			default:
				return nil
			}
		} catch { return nil }
	}


	public var object: AnyObject {
		switch self {
		case let .Number(n):
			return n
		case let .Boolean(b):
			return b
		case let .String(s):
			return s
		case let .Array(a):
			return a.map { $0.object }
		case let .Dictionary(d):
			return Swift.Dictionary(elements: d.map { ($0, $1.object) })
		case .Null:
			return NSNull()
		}
	}

	public func serialize() -> NSData {
		return try! NSJSONSerialization.dataWithJSONObject(object, options: [])
	}


	// MARK: ArrayLiteralConvertible

	public init(arrayLiteral: Doubt.JSON...) {
		self = .Array(arrayLiteral)
	}


	// MARK: BooleanLiteralConvertible

	public init(booleanLiteral: Bool) {
		self = .Boolean(booleanLiteral)
	}


	// MARK: DictionaryLiteralConvertible

	public init(dictionaryLiteral: (Swift.String, Doubt.JSON)...) {
		self = .Dictionary(Swift.Dictionary(elements: dictionaryLiteral))
	}


	// MARK: FloatLiteralConvertible

	public init(floatLiteral: Double) {
		self = .Number(floatLiteral)
	}


	// MARK: IntegerLiteralConvertible

	public init(integerLiteral: Int) {
		self = .Number(Double(integerLiteral))
	}


	// MARK: JSONConvertible

	public init?(JSON: Doubt.JSON) {
		self = JSON
	}

	public var JSON: Doubt.JSON {
		return self
	}


	// MARK: NilLiteralConvertible

	public init(nilLiteral: ()) {
		self = .Null
	}


	// MARK: StringLiteralConvertible

	public init(stringLiteral: Swift.String) {
		self = .String(stringLiteral)
	}
}


public func == (left: JSON, right: JSON) -> Bool {
	switch (left, right) {
	case let (.Number(a), .Number(b)):
		return a == b
	case let (.Boolean(a), .Boolean(b)):
		return a == b
	case let (.String(a), .String(b)):
		return a == b
	case let (.Array(a), .Array(b)):
		return a == b
	case let (.Dictionary(a), .Dictionary(b)):
		return a == b
	case (.Null, .Null):
		return true
	default:
		return false
	}
}


/// A type which can be converted to JSON.
public protocol CustomJSONConvertible {
	var JSON: Doubt.JSON { get }
}

extension String: CustomJSONConvertible {
	public var JSON: Doubt.JSON {
		return .String(self)
	}
}

extension Int: CustomJSONConvertible {
	public var JSON: Doubt.JSON {
		return .Number(Double(self))
	}
}

extension Array where Element: CustomJSONConvertible {
	public var JSON: Doubt.JSON {
		return .Array(map { Doubt.JSON($0) })
	}
}

extension Range where Element: CustomJSONConvertible, Element.Distance: CustomJSONConvertible {
	public var JSON: Doubt.JSON {
		return [
			startIndex.JSON,
			count.JSON,
		]
	}
}


/// A type which can be converted to and from JSON.
public protocol JSONConvertible: CustomJSONConvertible {
	init?(JSON: Doubt.JSON)
}


import Foundation