Update formatting

submodules/BotPaymentsUI/Sources/Formatter/String.swift

@@ -0,0 +1,69 @@
+//
+//  String.swift
+//  CurrencyText
+//
+//  Created by Felipe Lefèvre Marino on 4/3/18.
+//  Copyright © 2018 Felipe Lefèvre Marino. All rights reserved.
+//
+
+import Foundation
+
+public protocol CurrencyString {
+    var representsZero: Bool { get }
+    var hasNumbers: Bool { get }
+    var lastNumberOffsetFromEnd: Int? { get }
+    func numeralFormat() -> String
+    mutating func updateDecimalSeparator(decimalDigits: Int)
+}
+
+//Currency String Extension
+extension String: CurrencyString {
+
+    // MARK: Properties
+    
+    /// Informs with the string represents the value of zero
+    public var representsZero: Bool {
+        return numeralFormat().replacingOccurrences(of: "0", with: "").count == 0
+    }
+    
+    /// Returns if the string does have any character that represents numbers
+    public var hasNumbers: Bool {
+        return numeralFormat().count > 0
+    }
+
+    /// The offset from end index to the index _right after_ the last number in the String.
+    /// e.g. For the String "123some", the last number position is 4, because from the _end index_ to the index of _3_
+    /// there is an offset of 4, "e, m, o and s".
+    public var lastNumberOffsetFromEnd: Int? {
+        guard let indexOfLastNumber = lastIndex(where: { $0.isNumber }) else { return nil }
+        let indexAfterLastNumber = index(after: indexOfLastNumber)
+        return distance(from: endIndex, to: indexAfterLastNumber)
+    }
+
+    // MARK: Functions
+    
+    /// Updates a currency string decimal separator position based on
+    /// the amount of decimal digits desired
+    ///
+    /// - Parameter decimalDigits: The amount of decimal digits of the currency formatted string
+    public mutating func updateDecimalSeparator(decimalDigits: Int) {
+        guard decimalDigits != 0 && count >= decimalDigits else { return }
+        let decimalsRange = index(endIndex, offsetBy: -decimalDigits)..<endIndex
+        
+        let decimalChars = self[decimalsRange]
+        replaceSubrange(decimalsRange, with: "." + decimalChars)
+    }
+    
+    /// The numeral format of a string - remove all non numerical ocurrences
+    ///
+    /// - Returns: itself without the non numerical characters ocurrences
+    public func numeralFormat() -> String {
+        return replacingOccurrences(of:"[^0-9]", with: "", options: .regularExpression)
+    }
+}
+
+// MARK: - Static constants
+
+extension String {
+    public static let negativeSymbol = "-"
+}