TreeView.swift

//
//  TreeView.swift
//  ----------------
//
//  Created by Utku Yeğen on 19.12.2024.
//

import SwiftUI

struct TreeBranch {
    let id: UUID = .init()
    let title: String
    let leafs: [TreeBranch]
}

struct TreeView: View {
    let id: UUID = .init()
    let tree: [TreeBranch] = [
        .init(title: "Tree 1", leafs: [
            .init(title: "Leaf 1", leafs: [
                .init(title: "Leaf 1.1", leafs: [
                    .init(title: "Leaf 1.1.1", leafs: []),
                    .init(title: "Leaf 1.1.2", leafs: []),
                    .init(title: "Leaf 1.1.3", leafs: []),
                    .init(title: "Leaf 1.1.4", leafs: [])
                ])
            ]),
            .init(title: "Leaf 2", leafs: []),
            .init(title: "Leaf 3", leafs: []),
            .init(title: "Leaf 4", leafs: []),
            .init(title: "Leaf 5", leafs: [])
        ]),
        .init(title: "Tree 2", leafs: []),
        .init(title: "Tree 3", leafs: [
            .init(title: "Leaf 3", leafs: []),
            .init(title: "Leaf 4", leafs: []),
            .init(title: "Leaf 5", leafs: [])
        ]),
        .init(title: "Tree 4", leafs: [])
    ]
    
    var body: some View {
        ScrollView {
            ForEach(tree, id: \.id) { branch in
                TreeRow(branch: branch, depth: 0)
            }
            .padding(.horizontal, 16)
        }
    }
}

struct TreeRow: View {
    let branch: TreeBranch
    let depth: Int
    
    var body: some View {
        VStack {
            VStack {
                HStack {
                    Text(branch.title)
                    Spacer()
                    Text("\(depth)")
                }
                .padding(.leading, CGFloat(depth) * 10)
                
                buildSeperator()
                
                if !branch.leafs.isEmpty {
                    ForEach(branch.leafs, id: \.id) { leaf in
                        TreeRow(branch: leaf, depth: depth + 1)
                    }
                }
            }
            .padding(.vertical, 8)
            
        }
    }
    
    @ViewBuilder
    private func buildSeperator() -> some View {
        Rectangle()
            .frame(height: 1)
    }
}

#Preview {
    TreeView()
}