RouterOS/RouterOSAssistant/Features/Overview/OverviewLayout.swift

import CoreGraphics

/// Fixed column/row grid layout for the Übersicht diagram — pure geometry, no SwiftUI. Columns
/// follow the dependency order left-to-right (interfaces are the foundation everything else
/// attaches to); nodes within a column are stacked top-to-bottom, sorted so repeated runs render
/// in a stable order across reloads.
struct OverviewLayoutResult {
    var positions: [String: CGPoint] = [:]
    var canvasSize: CGSize = .zero
}

enum OverviewLayout {
    static let columnOrder: [OverviewNode.Category] = [.interface, .ipAddress, .service, .route, .firewall]
    static let columnWidth: CGFloat = 220
    static let rowHeight: CGFloat = 64
    static let nodeWidth: CGFloat = 180
    static let nodeHeight: CGFloat = 50
    static let topInset: CGFloat = 44
    static let leftInset: CGFloat = 40

    static func layout(for graph: OverviewGraph) -> OverviewLayoutResult {
        var positions: [String: CGPoint] = [:]
        var maxRows = 0
        for (columnIndex, category) in columnOrder.enumerated() {
            let nodesInColumn = graph.nodes
                .filter { $0.category == category }
                .sorted { lhs, rhs in
                    lhs.kind == rhs.kind ? lhs.title < rhs.title : lhs.kind < rhs.kind
                }
            maxRows = max(maxRows, nodesInColumn.count)
            let x = leftInset + CGFloat(columnIndex) * columnWidth + nodeWidth / 2
            for (row, node) in nodesInColumn.enumerated() {
                let y = topInset + CGFloat(row) * rowHeight + nodeHeight / 2
                positions[node.id] = CGPoint(x: x, y: y)
            }
        }
        let width = leftInset * 2 + CGFloat(columnOrder.count) * columnWidth
        let height = topInset * 2 + CGFloat(max(maxRows, 1)) * rowHeight
        return OverviewLayoutResult(positions: positions, canvasSize: CGSize(width: width, height: height))
    }
}