import SwiftUI

struct MapAxes: View {

  let mapSize: CGSize
  let lineWidth: CGFloat
  let evolution: Stage
  let stages: [CGFloat]
  let stageHeight = CGFloat(100.0)
  let padding = CGFloat(5.0)

  var body: some View {
    ZStack(alignment: .topLeading) {

      // Axis Lines
      Path { path in
        path.move(to: CGPoint(x: 0, y: 0))
        path.addLine(to: CGPoint(x: 0, y: mapSize.height))
        path.addLine(to: CGPoint(x: mapSize.width, y: mapSize.height))
        path.move(to: CGPoint(x: mapSize.width, y: mapSize.height))
        path.closeSubpath()
      }.stroke(Color.map.axisColor, lineWidth: lineWidth * 2)

      // Y Labels
      Text("Visible").font(.theme.axisLabel).foregroundColor(.map.labelColor).rotationEffect(Angle(degrees: -90.0))
        .offset(CGSize(width: -35.0, height: 0.0))
      Text("Invisible").font(.theme.axisLabel).foregroundColor(.map.labelColor).rotationEffect(Angle(degrees: -90.0))
        .offset(CGSize(width: -40.0, height: mapSize.height - 20))

      // X Labels

      Text("Uncharted")
        .font(.theme.axisLabel)
        .foregroundColor(.map.labelColor)
        .frame(width: mapSize.width / 4, height: stageHeight / 2.0, alignment: .topLeading)
        .offset(CGSize(width: 0.0, height: -stageHeight / 4.0))
      Text("Industrialised")
        .font(.theme.axisLabel)
        .foregroundColor(.map.labelColor)
        .frame(width: mapSize.width / 4, height: stageHeight / 2.0, alignment: .topLeading)
        .offset(CGSize(width: mapSize.width - 100.0, height: -stageHeight / 4.0))

      Text(evolution.i)
        .font(.theme.axisLabel)
        .foregroundColor(.map.labelColor)
        .frame(width: w(stages[0]), height: stageHeight, alignment: .topLeading)
        .offset(CGSize(width: 0.0, height: mapSize.height + padding))

      Text(evolution.ii)
        .font(.theme.axisLabel)
        .foregroundColor(.map.labelColor)
        .frame(width: w(stages[1]) - w(stages[0]), height: stageHeight, alignment: .topLeading)
        .offset(CGSize(width: w(stages[0]), height: mapSize.height + padding))

      Text(evolution.iii)
        .font(.theme.axisLabel)
        .foregroundColor(.map.labelColor)
        .frame(width: w(stages[2]) - w(stages[1]), height: stageHeight, alignment: .topLeading)
        .offset(CGSize(width: w(stages[1]), height: mapSize.height + padding))

      Text(evolution.iv)
        .font(.theme.axisLabel)
        .foregroundColor(.map.labelColor)
        .frame(width: mapSize.width - w(stages[2]), height: stageHeight, alignment: .topLeading)
        .offset(CGSize(width: w(stages[2]), height: mapSize.height + padding))
    }
  }

  func w(_ dimension: CGFloat) -> CGFloat {
    max(0.0, min(mapSize.width, dimension * mapSize.width / 100.0))
  }
}

struct MapAxes_Previews: PreviewProvider {
  static var previews: some View {
    MapAxes(
      mapSize: CGSize(width: 200.0, height: 200.0), lineWidth: CGFloat(1.0),
      evolution: Stage.stages(.general), stages: [25.0, 50.0, 75.0]
    ).padding(50.0)
  }
}