RatingsView.swift

//
//  RatingsView.swift
//  RatingsView
//
//  Created by Jason Jobe on 9/12/21.
//
import SwiftUI

public struct RatingsView: View {
    var rating: CGFloat
    var maxRating: Int
    var symbol: String
    var color: Color
    var backgroundColor: Color
    
    public init(_ rating: CGFloat, of max: Int, symbol: String = "star.fill",
                color: Color = .yellow, backgroundColor: Color = .white) {
        self.rating = rating
        self.maxRating = max
        self.symbol = symbol
        self.color = color
        self.backgroundColor = backgroundColor
    }
    
    public var body: some View {
        let stars = HStack(spacing: 8) {
            ForEach(0..<maxRating) { _ in
                Image(systemName: symbol)
                    .resizable()
                    .aspectRatio(contentMode: .fit)
                    .shadow(radius: 1)
            }
        }
        
        stars.overlay(
            GeometryReader { g in
                let width = rating / CGFloat(maxRating) * g.size.width
                ZStack(alignment: .leading) {
                    Rectangle()
                        .frame(width: width)
                        .foregroundColor(color)
                }
            }
                .mask(stars)
        )
            .foregroundColor(backgroundColor)
    }
}

struct RatingsView_Previews: PreviewProvider {
    static var previews: some View {
        RatingsView(3.5, of: 5)
            .padding()
    }
}