Contents.swift

import Flow
import PlaygroundSupport
import SwiftUI

func simplePatch() -> Patch {
    let midiSource = Node(name: "MIDI source",
                          outputs: [
                              Port(name: "out ch. 1", type: .midi),
                              Port(name: "out ch. 2", type: .midi),
                          ])
    let generator = Node(name: "generator",
                         inputs: [
                             Port(name: "midi in", type: .midi),
                             Port(name: "CV in", type: .control),
                         ],
                         outputs: [Port(name: "out")])
    let processor = Node(name: "processor", inputs: ["in"], outputs: ["out"])
    let mixer = Node(name: "mixer", inputs: ["in1", "in2"], outputs: ["out"])
    let output = Node(name: "output", inputs: ["in"])

    let nodes = [midiSource, generator, processor, generator, processor, mixer, output]

    let wires = Set([
        Wire(from: OutputID(0, 0), to: InputID(1, 0)),
        Wire(from: OutputID(0, 1), to: InputID(3, 0)),
        Wire(from: OutputID(1, 0), to: InputID(2, 0)),
        Wire(from: OutputID(2, 0), to: InputID(5, 0)),
        Wire(from: OutputID(3, 0), to: InputID(4, 0)),
        Wire(from: OutputID(4, 0), to: InputID(5, 1)),
        Wire(from: OutputID(5, 0), to: InputID(6, 0)),
    ])

    var patch = Patch(nodes: nodes, wires: wires)
    patch.recursiveLayout(nodeIndex: 6, at: CGPoint(x: 1000, y: 50))
    return patch
}

struct FlowDemoView: View {
    @State var patch = simplePatch()
    @State var selection = Set<NodeIndex>()

    public var body: some View {
        NodeEditor(patch: $patch, selection: $selection)
            .nodeColor(.secondary)
            .portColor(for: .control, .gray)
            .portColor(for: .signal, Gradient(colors: [.yellow, .blue]))
            .portColor(for: .midi, .red)

            .onNodeMoved { index, location in
                print("Node at index \(index) moved to \(location)")
            }
            .onWireAdded { wire in
                print("Added wire: \(wire)")
            }
            .onWireRemoved { wire in
                print("Removed wire: \(wire)")
            }
    }
}

PlaygroundPage.current.setLiveView(FlowDemoView().frame(width: 1200, height: 500))
PlaygroundPage.current.needsIndefiniteExecution = true