Trying to backport the `safeAreaInset` modifier to iOS 14

ContentView.swift

struct ContentView: View {
	@State private var text = ""
	
    var body: some View {
		ScrollView {
			LazyVStack(alignment: .leading) {
				ForEach(1 ..< 20) { number in
					Text("Row number \(number)")
						.padding()
				}
			}
		}
		.background(
			LinearGradient(
				gradient: Gradient(colors: [.blue, .green]),
				startPoint: .topLeading,
				endPoint: .bottomTrailing
			)
			.ignoresSafeArea()
		)
//		.overlay(
//			searchField,
//			alignment: .bottom
//		)
		.safeAreaInset(edge: .bottom) {
			searchField
		}
    }
	
	var searchField: some View {
		TextField("Some Text Goes Here", text: $text)
			.padding()
			.background(RoundedRectangle(cornerRadius: 16).fill(Color.white))
			.padding()
	}
}

SafeAreaInset.swift

import SwiftUI

struct HeightPreferenceKey: PreferenceKey {
	static var defaultValue: CGFloat { 0 }
	
	static func reduce(value: inout CGFloat, nextValue: () -> CGFloat) {
		value = nextValue()
	}
}

enum HorizontalEdge {
	case top, bottom
}

extension EdgeInsets {
	init(_ edge: HorizontalEdge, _ inset: CGFloat) {
		switch edge {
		case .top: self.init(top: inset, leading: 0, bottom: 0, trailing: 0)
		case .bottom: self.init(top: 0, leading: 0, bottom: inset, trailing: 0)
		}
	}
	
	func uiEdgeInsets(in direction: LayoutDirection) -> UIEdgeInsets {
		if direction == .rightToLeft {
			return UIEdgeInsets(top: top, left: leading, bottom: bottom, right: trailing)
		} else {
			return UIEdgeInsets(top: top, left: leading, bottom: bottom, right: trailing)
		}
	}
}

struct AdditionalSafeAreaInsetsView<Content: View>: UIViewControllerRepresentable {
	let insets: EdgeInsets
	@ViewBuilder var content: () -> Content
	
	@Environment(\.layoutDirection) private var layoutDirection
	
	func makeUIViewController(context: Context) -> UIHostingController<Content> {
		let viewController = UIHostingController(rootView: content())
		viewController.additionalSafeAreaInsets = insets.uiEdgeInsets(in: layoutDirection)
		return viewController
	}
	
	func updateUIViewController(_ uiViewController: UIHostingController<Content>, context: Context) {
		uiViewController.additionalSafeAreaInsets = insets.uiEdgeInsets(in: layoutDirection)
		uiViewController.rootView = content()
	}
}

struct SafeAreaInsetView<Base: View, Bar: View>: View {
	let edge: HorizontalEdge
	let base: Base
	@ViewBuilder let content: () -> Bar
	
	@State private var barHeight: CGFloat = 0
	
	var body: some View {
		let alignment: Alignment = {
			switch edge {
			case .top: return .top
			case .bottom: return .bottom
			}
		}()
		
		AdditionalSafeAreaInsetsView(insets: EdgeInsets(edge, barHeight)) {
			base
		}
		.overlay(
			content()
				.background(
					GeometryReader { proxy in
						Color.clear.preference(key: HeightPreferenceKey.self, value: proxy.size.height)
					}
					.onPreferenceChange(HeightPreferenceKey.self) { value in
						self.barHeight = value
					}
				),
			alignment: alignment
		)
	}
}

extension View {
	func safeAreaInset<Content: View>(
		edge: HorizontalEdge,
		@ViewBuilder _ content: @escaping () -> Content
	) -> some View {
		SafeAreaInsetView(edge: edge, base: self, content: content)
	}
}