// Example 7: Neural Network Diagram with CeTZ

#import "@preview/cetz:0.4.2"

#set text(font: "Libertinus Serif", size: 11pt)
#set page(width: auto, height: auto, margin: 0.5cm)

#cetz.canvas({
  import cetz.draw: *

  let input-y = (8, 6.2, 4.4, 2.6)
  let hidden-y = (8, 6.5, 5, 3.5, 2)
  let output-y = (7, 4)

  // Input layer
  for i in range(4) {
    circle((0, input-y.at(i)), radius: 0.4, fill: blue.lighten(70%), stroke: black)
    content((0, input-y.at(i)), [#i], anchor: "center")
  }

  // Hidden layer
  for i in range(5) {
    circle((4, hidden-y.at(i)), radius: 0.4, fill: green.lighten(70%), stroke: black)
  }

  // Output layer
  for i in range(2) {
    circle((8, output-y.at(i)), radius: 0.4, fill: red.lighten(70%), stroke: black)
  }

  // Connections
  for ix in range(4) {
    for jx in range(5) {
      line(
        (0.4, input-y.at(ix)),
        (3.6, hidden-y.at(jx)),
        stroke: gray + 0.3pt
      )
    }
  }

  for ix in range(5) {
    for jx in range(2) {
      line(
        (4.4, hidden-y.at(ix)),
        (7.6, output-y.at(jx)),
        stroke: gray + 0.3pt
      )
    }
  }

  // Labels
  content((0, -0.3), [Input], anchor: "north")
  content((4, -0.3), [Hidden], anchor: "north")
  content((8, -0.3), [Output], anchor: "north")
})