#let default-color = white.darken(10%)
#let header-color = default-color.lighten(75%)
#let body-color = white.darken(10%)
#let code-font = "Fira Code"
#let code_theme = "halcyon.tmTheme"
#let darken = rgb(0, 0, 0, 50%)
#let fontsize = 11pt

#let layouts = (
  "small": ("height": 9cm, "space": 1.4cm),
  "medium": ("height": 10.5cm, "space": 1.6cm),
  "large": ("height": 12cm, "space": 1.8cm),
)

#let slides(
  content,
  title: none,
  subtitle: none,
  comment: none,
  date: none,
  authors: (),
  layout: "medium",
  ratio: 4 / 3,
  title-color: none,
  background: none,
) = {
  // Parsing
  if layout not in layouts {
    panic("Unknown layout " + layout)
  }
  let (height, space) = layouts.at(layout)
  let width = ratio * height

  // Colors
  if title-color == none {
    title-color = default-color
  }

  // Setup
  set document(
    title: title,
    author: authors,
  )
  //
  set text(
    font: "Fira Code",
    fill: white,
    size: fontsize,
  )
  set page(
    width: width,
    height: height,
    margin: (x: 0.5 * space, top: 1.1 * space, bottom: 0.6 * space),
    //background: image("../images/" + background),
    background: {
      if background != none {
        rect(width: 100%, height: 100%, inset: 0pt, outset: 0pt)[
          #image("../images/" + background, width: 100%, height: 100%, fit: "cover")
          #place(top + left)[
            #rect(width: 100%, height: 40pt, fill: rgb(0, 0, 0, 70%))
          ]
          #place(top + left)[
            #rect(
              width: 100%,
              height: 100%,
              fill: rgb(0, 0, 0, 70%),
            )
          ]
          #place(top + right, dx: -2pt, dy: 2pt)[
            #image("../images/logo.jpg", height: 12%)
          ]
          #place(bottom + right, dx: -2pt, dy: -2pt)[
            #image("../images/qr-code.jpg", height: 10%)
          ]
        ]
      }
    },
    numbering: "1 / 1",
    header: context {
      let page = here().page()
      let headings = query(selector(heading.where(level: 2)))
      let heading = headings.rev().find(x => x.location().page() <= page)
      if heading != none {
        set align(top + center)
        set text(0.8em, weight: "bold", fill: title-color)
        v(space * 0.1)
        upper(title)
        v(space * 0.001)
        text(size: 0.8em, upper(heading.body))
      }
    },
    header-ascent: 0%,
    footer: [
      #set text(0.6em)
      #set align(left)
      #context [#counter(page).display("1/1", both: true)]
    ],
    footer-descent: 0.8em,
  )
  set outline(
    target: heading.where(level: 2),
    title: none,
  )
  set bibliography(
    title: none,
  )

  show table: set table(stroke: 0.5pt + rgb("c0c0c0"))

  // Rules
  show heading.where(level: 1): x => {
    set page(header: none, footer: none)
    set align(center + horizon)
    set text(1.2em, weight: "bold", fill: title-color)
    v(-space / 2)
    x.body
  }
  show heading.where(level: 2): pagebreak(weak: true)
  show heading: set text(1.1em, fill: title-color)

  // Title
  if (title == none) {
    panic("A title is required")
  } else {
    if (type(authors) != array) {
      authors = (authors,)
    }
    set page(footer: none)
    set align(horizon + center)
    v(-space / 2)
    block(
      text(2.0em, weight: "bold", fill: title-color, title)
        + v(1.0em, weak: true)
        + if subtitle != none { text(1.4em, weight: "bold", fill: title-color, subtitle) }
        + v(1.0em, weak: true)
        + if comment != none { text(1.0em, weight: "bold", fill: title-color, comment) }
        + if subtitle != none and date != none { text(1.1em)[ \- ] }
        + if date != none { text(1.1em, date) }
        + v(1.6em, weak: true)
        + align(center, text(fill: title-color, authors.join(", ", last: " and "))),
    )
  }

  // Raw
  set raw(
    theme: code_theme,
    tab-size: 4,
  )
  show raw.where(block: true): item => {
    set block(fill: rgb("#1d2433"))
    box(
      fill: rgb("#1d2433"),
      inset: 4pt,
      radius: 8pt,
      text(fill: rgb("#a2aabc"), font: code-font, size: 10pt, item),
    )
  }
  show raw.where(block: false): item => box(
    fill: rgb("#1d2433"),
    inset: 4pt,
    radius: 4pt,
    text(fill: rgb("#a2aabc"), font: code-font, size: 10pt, item),
  )

  // Content
  content
}