SwiftyTimer.swift

//
// SwiftyTimer
//
// Copyright (c) 2015-2016 Radosław Pietruszewski
//
// 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

extension Timer {
    
// MARK: Schedule timers
    
    /// Create and schedule a timer that will call `block` once after the specified time.
    
    @discardableResult
    public class func after(_ interval: TimeInterval, runLoop: RunLoop = .current, modes: RunLoopMode..., _ block: @escaping () -> Void) -> Timer {
        let timer = Timer.new(after: interval, block)
        timer.start(runLoop: runLoop, modes: modes)
        return timer
    }
    
    /// Create and schedule a timer that will call `block` repeatedly in specified time intervals.
    
    @discardableResult
    public class func every(_ interval: TimeInterval, runLoop: RunLoop = .current, modes: RunLoopMode..., _ block: @escaping () -> Void) -> Timer {
        let timer = Timer.new(every: interval, block)
        timer.start(runLoop: runLoop, modes: modes)
        return timer
    }
    
    /// Create and schedule a timer that will call `block` repeatedly in specified time intervals.
    /// (This variant also passes the timer instance to the block)
    
    @nonobjc @discardableResult
    public class func every(_ interval: TimeInterval, runLoop: RunLoop = .current, modes: RunLoopMode..., _ block: @escaping (Timer) -> Void) -> Timer {
        let timer = Timer.new(every: interval, block)
        timer.start(runLoop: runLoop, modes: modes)
        return timer
    }
    
// MARK: Create timers without scheduling
    
    /// Create a timer that will call `block` once after the specified time.
    ///
    /// - Note: The timer won't fire until it's scheduled on the run loop.
    ///         Use `NSTimer.after` to create and schedule a timer in one step.
    /// - Note: The `new` class function is a workaround for a crashing bug when using convenience initializers (rdar://18720947)

    public class func new(after interval: TimeInterval, _ block: @escaping () -> Void) -> Timer {
        return CFRunLoopTimerCreateWithHandler(kCFAllocatorDefault, CFAbsoluteTimeGetCurrent() + interval, 0, 0, 0) { _ in
            block()
        }
    }
    
    /// Create a timer that will call `block` repeatedly in specified time intervals.
    ///
    /// - Note: The timer won't fire until it's scheduled on the run loop.
    ///         Use `NSTimer.every` to create and schedule a timer in one step.
    /// - Note: The `new` class function is a workaround for a crashing bug when using convenience initializers (rdar://18720947)

    public class func new(every interval: TimeInterval, _ block: @escaping () -> Void) -> Timer {
        return CFRunLoopTimerCreateWithHandler(kCFAllocatorDefault, CFAbsoluteTimeGetCurrent() + interval, interval, 0, 0) { _ in
            block()
        }
    }
    
    /// Create a timer that will call `block` repeatedly in specified time intervals.
    /// (This variant also passes the timer instance to the block)
    ///
    /// - Note: The timer won't fire until it's scheduled on the run loop.
    ///         Use `NSTimer.every` to create and schedule a timer in one step.
    /// - Note: The `new` class function is a workaround for a crashing bug when using convenience initializers (rdar://18720947)
    
    @nonobjc public class func new(every interval: TimeInterval, _ block: @escaping (Timer) -> Void) -> Timer {
        var timer: Timer!
        timer = CFRunLoopTimerCreateWithHandler(kCFAllocatorDefault, CFAbsoluteTimeGetCurrent() + interval, interval, 0, 0) { _ in
            block(timer)
        }
        return timer
    }
    
// MARK: Manual scheduling
    
    /// Schedule this timer on the run loop
    ///
    /// By default, the timer is scheduled on the current run loop for the default mode.
    /// Specify `runLoop` or `modes` to override these defaults.
    
    public func start(runLoop: RunLoop = .current, modes: RunLoopMode...) {
        let modes = modes.isEmpty ? [.defaultRunLoopMode] : modes
        
        for mode in modes {
            runLoop.add(self, forMode: mode)
        }
    }
    
    /// Schedule this timer on the run loop
    ///
    /// By default, the timer is scheduled on the current run loop for the default mode.
    /// Specify `runLoop` or `modes` to override these defaults.
    /// Usefull since the splat operator is not a thing in Swift
    
    public func start(runLoop: RunLoop = .current, modes: [RunLoopMode]) {
        let modes = modes.isEmpty ? [.defaultRunLoopMode] : modes
        
        for mode in modes {
            runLoop.add(self, forMode: mode)
        }
    }
}

// MARK: - Time extensions

extension Double {
    public var millisecond: TimeInterval  { return self / 1000 }
    public var milliseconds: TimeInterval { return self / 1000 }
    public var ms: TimeInterval           { return self / 1000 }
    
    public var second: TimeInterval       { return self }
    public var seconds: TimeInterval      { return self }
    
    public var minute: TimeInterval       { return self * 60 }
    public var minutes: TimeInterval      { return self * 60 }
    
    public var hour: TimeInterval         { return self * 3600 }
    public var hours: TimeInterval        { return self * 3600 }
    
    public var day: TimeInterval          { return self * 3600 * 24 }
    public var days: TimeInterval         { return self * 3600 * 24 }
}