MaskTextField-SwiftUI.swift

MaskTextField.swift

import SwiftUI
import Combine

public protocol Mask {
    var maskFormat: String { get set }
    func formateValue(_ value: String) -> String
}

extension Mask {
    public func formateValue(_ value: String) -> String {
        let cleanPhoneNumber = value.components(separatedBy: CharacterSet.decimalDigits.inverted).joined()
        let mask = maskFormat
        var result = ""
        var index = cleanPhoneNumber.startIndex
        for ch in mask where index < cleanPhoneNumber.endIndex {
            if ch == "#" {
                result.append(cleanPhoneNumber[index])
                index = cleanPhoneNumber.index(after: index)
            } else {
                result.append(ch)
            }
        }
        return result
    }
}

public struct MSTextField: View {
    @State private var focused: Bool = false
    @Binding private var text: String
    private let title: String
    private let placeholder: String
    private let mask: Mask?
    
    public init(title: String, placeholder: String, text: Binding<String>, mask: Mask? = nil) {
        self.title = title
        self.placeholder = placeholder
        self._text = text
        self.mask = mask
    }
    
    public var body: some View {
        VStack(
            alignment: .leading,
            spacing: DS.Spacing.Stack.tiny
        ) {
            Text(title)
                .style(size: .preMedium, weight: .regular)
            TextField(placeholder, text: $text, onEditingChanged: { edit in
                self.focused = edit
            })
            .onReceive(Just(text), perform: { text in
                self.text = mask?.formateValue(text) ?? text
            })
        }
    }
}