#import "metadata.typ": author-text, format-date
#import "color/rose-pine-dawn.typ": rose-pine-dawn as dawn
#import "color/rose-pine-moon.typ": rose-pine-moon as moon

#let code-theme = moon.codeThemePath

#let rule(length: 100%, fade-both: false) = line(
  length: length,
  stroke: 1pt + if fade-both {
    gradient.linear(
      (dawn.rose.transparentize(100%), 0%),
      (dawn.rose, 15%),
      (dawn.rose, 85%),
      (dawn.rose.transparentize(100%), 100%),
      angle: 0deg,
    )
  } else {
    gradient.linear(
      (dawn.rose, 0%),
      (dawn.rose, 55%),
      (dawn.rose.transparentize(100%), 65%),
      (dawn.rose.transparentize(100%), 100%),
      angle: 0deg,
    )
  },
)

#let pdf-header(ctx) = {
  let info = ctx.page

  set par(spacing: 9pt)
  if info.title != none { text(size: 28pt, weight: "bold", fill: dawn.text, info.title) }
  if info.subtitle != none [
    #parbreak()
    #text(size: 14pt, fill: dawn.subtle, info.subtitle)
  ]
  v(1em)
  if info.by.len() > 0 [
    #parbreak()
    #text(size: 12pt, fill: dawn.subtle, [#author-text(info.by)])
  ]
  if info.date != none [
    #parbreak()
    #text(size: 12pt, fill: dawn.iris, format-date(info.date))
  ]
  if info.description != none [
    #parbreak()
    #v(1em)
    #info.description
  ]
  rule()
}

#let page-band(ctx, top: true) = context {
  set text(size: 8pt, fill: dawn.subtle)
  let info = ctx.page
  let title = if info.title == none { ctx.site.title } else { info.title }
  let url = ctx.page.at("url", default: none)
  let author = info.author.join(", ")
  let date = if info.date != none { format-date(info.date) } else { [] }
  let details = grid(
    columns: (1fr, auto),
    column-gutter: 12pt,
    align: (left, right),
    if top { if url == none { title } else { link(url, title) } } else { author },
    if top { date } else { counter(page).display("1") },
  )
  if top {
    stack(dir: ttb, spacing: 6pt, details, rule(fade-both: true))
  } else {
    stack(dir: ttb, spacing: 6pt, rule(fade-both: true), details)
  }
}

#let pdf-layout(ctx, body) = [
  #show raw.where(block: true): set raw(theme: code-theme)
  #set text(font: "Montserrat", size: 11pt, fill: dawn.text)
  #show math.equation: set text(font: "Fira Math", fallback: false)
  #show raw.where(block: true): it => block(
    width: 100%,
    fill: moon.base,
    inset: 10pt,
    radius: 6pt,
    breakable: true,
  )[
    #set text(fill: moon.text)
    #it
  ]
  #show heading: set text(size: 1.1em)
  #show heading.where(depth: 1): it => [
    #it
    #block(above: 0pt, below: 8pt, rule(length: 55%))
  ]
  #set page(
    margin: 1in,
    fill: dawn.base,
    header: page-band(ctx),
    footer: page-band(ctx, top: false),
    paper: "us-letter",
  )
  #(ctx.site.theme.header)(ctx)
  #body
]