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//
//  TextStyle.swift
//
//  Created by Rob Napier on 12/20/19.
//  Copyright © 2019 Rob Napier. All rights reserved.
//

import SwiftUI

public struct TextStyle {

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// From https://stackoverflow.com/questions/54129682/use-swift-codable-to-decode-json-with-values-as-keys
import Foundation

let json = Data("""
{
  "7E7-M001" : {
    "Drawer1" : {
      "101" : {
        "Partnumber" : "F101"
      },

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// Based on https://twitter.com/ravibastola/status/1249555595285291008?s=20

extension Bundle {
    // This is synchronous, which is bad if called on the main queue.
    func decodeJSON<T: Decodable>(_ type: T.Type = T.self, from filename: String) throws -> T {
        guard let path = self.url(forResource: filename, withExtension: nil) else {
            throw NSError(domain: NSCocoaErrorDomain,
                          code: CocoaError.fileNoSuchFile.rawValue,
                          userInfo: [NSFilePathErrorKey: filename])
        }

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import Foundation

class Disposable {
    let dispose: () -> Void
    init(dispose: @escaping () -> Void) { self.dispose = dispose }
    deinit {
        dispose()
    }
}

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// Swift3 gets rid of dispatch_once and recommends replacing it with a lazy global.
// That's very straightforward when dispach_once is used to initialize something, but
// isn't an exact match when you want something to execute once, and then become a noop
// in a thread-safe way.

// The following approach seems completely "correct" and I guess actually a bit elegant,
// if by "elegant" you mean "terse and not immediately obvious to the reader, which makes
// you look very clever."

var doOnce: () -> Void = {

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import Swift

/*:
    A simple type-erased sequence
*/
let seq = AnySequence([1,2,3])


/*:
    ## Who Needs Types Like That?

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import Foundation

@dynamicMemberLookup
enum JSON: Codable, CustomStringConvertible {
    var description: String {
        switch self {
        case .string(let string): return "\"\(string)\""
        case .number(let double):
            if let int = Int(exactly: double) {
                return "\(int)"

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///
/// Boring setup. See below for the good parts
///

public class Logger {
    public static let root = Logger(subsystem: .none, parent: nil)
    public let subsystem: Subsystem
    public let parent: Logger?
    public init(subsystem: Subsystem, parent: Logger? = .root) {
        self.subsystem = subsystem

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import Foundation

public protocol JSONStringConvertible: class {
    var jsonString: String { get }
}

extension Logger {
    // Converts an arbitrary object into some that is JSON-safe
    static func makeJSONObject(_ object: Any) -> Any {
        if let jsonObj = object as? JSONStringConvertible {

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  // Main thread priorty = 0.758065
  NSLog(@"main:%@:%f", [NSThread currentThread], [NSThread threadPriority]);

  // High priority = 0.532258
  dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
    NSLog(@"high:%@:%f", [NSThread currentThread], [NSThread threadPriority]);
    // run forever! Note that other queues still happily process, even though our high-priority block never ends
    while(1) {}
  });