// The website: one Typst bundle run writes every page, the stylesheet, the
// fonts and the media. Pages come from `chapters` in ../typ/style.typ, so a
// new chapter is a new page; the only prose of its own is the landing page.
//   typst compile --root . --format bundle --features bundle,html docs/site/site.typ OUT
// Every link is relative and every page sits at the top of OUT, so the site
// works from file:// and from any static server.
#import "../typ/style.typ": chapters, tutor-path, doc-links, project, btn, chord

#let clips = toml("media/clips.toml").clip
#let casts = toml("casts/casts.toml").cast
#let themes = toml("media/themes/themes.toml")
/// The version, from build.zig.zon: 0.23.0 reads 0.23.
#let version = {
  let v = read("/build.zig.zon").match(regex("\\.version\\s*=\\s*\"([^\"]+)\"")).captures.first()
  if v.ends-with(".0") and v.split(".").len() == 3 { v.slice(0, -2) } else { v }
}

// --- the landing page's own words: everything a visitor reads first ----------
// Change the landing here; the rest of the site is the chapters.
#let landing = (
  lead: [pardes is a text environment, after acme and helix, where any text
    is live: right-click `main.c:12` to open that line, middle-click `make`
    to run it, in source, PDFs and terminals alike, in a terminal or in its
    own window.],
  credit: [It is built on ideas from #link("https://9p.io/plan9/")[Plan 9] from
    Bell Labs: #link("https://9p.io/sys/doc/acme/acme.html")[acme]'s text as
    the interface, and the 9P protocol.],
  status: [Linux; macOS in progress. Version #version.],
  // what's in it: a word each, linked to where it is told; no prose
  // what's in it: each word jumps to its recording on this page when it
  // has one, and that recording's caption links on to the docs
  inside: (
    (name: "Terminals", rec: "terminals", docs: "guide.html#terminals"),
    (name: "PDFs", rec: "pdf-navigation", docs: "builtins.html#builtin-PdfSections"),
    (name: "Images", rec: "image-pane", docs: "reference.html#panes"),
    (name: "Language servers", rec: none, docs: "setup.html#language-servers"),
    (name: "Diff review", rec: "diff-review", docs: "guide.html#reviewing-diffs"),
    (name: "Scripting", rec: "scripting-over-9p", docs: "scripting.html"),
    (name: "Themes", rec: none, docs: "themes.html"),
  ),
  terminal: [In a terminal],
  window: [In its own window],
  start: (
    (id: "guide", label: [Start: the guide], note: [about 15 min]),
    (id: "tutor", label: [Hands on: the tutor], note: [run `Tutor` inside pardes]),
  ),
  install: [Install],
)
#let pages = (
  (id: "index", title: "pardes"),
  ..chapters.filter(c => c.file != none).map(c => (id: c.id, title: c.title, file: c.file)),
  (id: "tutor", title: "The tutor"),
)
#let href(id) = id + ".html"

// --- the files that are not pages --------------------------------------------

#asset("site.css", read("site.css", encoding: none))
#for f in ("DepartureMono-Regular.woff2", "CrimsonPro-VF-normal.woff2", "CrimsonPro-VF-italic.woff2",
           "LICENSE-DepartureMono.txt", "LICENSE-CrimsonPro.txt") {
  asset("fonts/" + f, read("fonts/" + f, encoding: none))
}
#asset("media/placeholder.svg", read("media/placeholder.svg", encoding: none))
#for f in ("asciinema-player.min.js", "asciinema-player.css", "LICENSE-asciinema-player.txt") {
  asset("player/" + f, read("player/" + f, encoding: none))
}
#if themes.at("ready", default: true) {
  for t in themes.theme { asset("media/themes/" + t.file, read("media/themes/" + t.file, encoding: none)) }
}
#for c in clips.filter(c => c.ready) {
  for ext in ("webm", "mp4", "png") {
    asset("media/" + c.name + "." + ext, read("media/" + c.name + "." + ext, encoding: none))
  }
}

// --- the shell every page sits in ---------------------------------------------

/// An HTML element: el("a", (href: "x.html"))[text], or el("li")[text].
#let el(tag, ..args) = {
  let p = args.pos()
  html.elem(tag, attrs: if p.len() > 1 { p.first() } else { (:) }, p.last())
}

/// The running head: a tagline, the way a pane's tag reads, with the path
/// of this page and the chapters as its words.
#let trail(id, title) = el("header", (class: "trail"))[
  #el("span", (class: "grip", "aria-hidden": "true"))[]
  #el("a", (class: "home", href: href("index")))[pardes]
  #if id != "index" {
    el("span", (class: "sep", "aria-hidden": "true"))[/]
    el("span", (class: "here", "aria-current": "page"))[#title]
  }
  #el("nav", (class: "words", "aria-label": "Chapters"))[
    #for p in pages.slice(1) {
      if p.id == id { el("a", (href: href(p.id), "aria-current": "page"))[#p.title] }
      else { el("a", (href: href(p.id)))[#p.title] }
    }
  ]
]

#let in-view-script = el("script")[#(
  "(() => { if (!('IntersectionObserver' in window)) return;
" +
  "  const p = el => el.player || (el.tagName === 'VIDEO' ? el : null);
" +
  "  const io = new IntersectionObserver(es => { for (const e of es) { const r = p(e.target); if (!r) continue;
" +
  "    if (e.isIntersecting) Promise.resolve(r.play()).catch(() => {}); else r.pause(); } }, {threshold: 0.25});
" +
  "  for (const el of document.querySelectorAll('.clip video, .cast .player')) io.observe(el);
" +
  "})();"
)]

#let shell(id, title, body) = html.html(lang: "en", {
  html.head({
    html.meta(charset: "utf-8")
    el("meta", (name: "viewport", content: "width=device-width, initial-scale=1"))[]
    el("meta", (name: "color-scheme", content: "dark light"))[]
    html.title(if id == "index" { "pardes" } else { title + " · pardes" })
    el("link", (rel: "stylesheet", href: "site.css"))[]
  })
  html.body({
    el("div", (class: "shell"))[
      #trail(id, title)
      #el("main", (class: "panel", "data-page": id))[
        #el("article", (class: "content"))[#body]
      ]
      #el("footer", (class: "colophon"))[
        pardes #version ·
        source: #project.mirrors.map(m => el("a", (href: m.web))[#m.name]).join(", ") ·
        #el("a", (href: project.changes))[changes] ·
        #if project.license != none [#project.license license · ]
        built from `docs/typ` with Typst ·
        #el("a", (href: "fonts/LICENSE-DepartureMono.txt"))[fonts] (OFL) ·
        #el("a", (href: "player/LICENSE-asciinema-player.txt"))[asciinema-player] (Apache-2.0)
      ]
    ]
    // after the page's own scripts (the landing's players), on every page
    // that has a recording
    in-view-script
  })
})

/// The headings of this page only, as a contents list, when there are
/// enough of them to need one.
#let toc(id) = context {
  let hs = query(selector(heading.where(level: 2)).after(label("start-" + id)).before(label("end-" + id)))
  if hs.len() >= 4 {
    el("nav", (class: "toc", "aria-label": "On this page"))[
      #el("div", (class: "toc-bar"))[#el("span")[On this page]]
      #el("ol")[#for h in hs { el("li")[#link(h.location(), h.body)] }]
    ]
  }
}

// --- the pages ------------------------------------------------------------------

#doc-links.update(true)

// Every recording plays by itself; the script below plays each only while
// it is on screen. Without the script, `autoplay` still plays them.
#let video(c) = el("video", (poster: "media/" + c.name + ".png", autoplay: "", muted: "", loop: "", playsinline: "",
    controls: ""))[
  #el("source", (src: "media/" + c.name + ".webm", type: "video/webm"))[]
  #el("source", (src: "media/" + c.name + ".mp4", type: "video/mp4"))[]
]
#let placeholder = el("img", (src: "media/placeholder.svg", alt: "", width: "640", height: "400"))[]

/// A recording's caption: its text (which may hold #link markup), then the
/// docs of the "What's in it" word that jumps here, if any.
#let caption(c) = {
  if c.caption.contains("#") { eval(c.caption, mode: "markup") } else { c.caption }
  let to = landing.inside.find(i => i.rec == c.name)
  if to != none [ #el("a", (class: "more", href: to.docs))[#to.name in the docs →]]
}

/// A terminal recording: a box the player fills, its data inline (so it
/// plays from file://), its caption under it.
#let ready-casts = casts.filter(c => c.ready)
#let cast(c, i) = el("figure", (class: if i == 0 { "clip cast first" } else { "clip cast" }, id: "rec-" + c.name))[
  #if c.ready { el("div", (class: "player", id: "cast-" + c.name, "aria-label": c.title))[] } else { placeholder }
  #el("figcaption")[#el("strong")[#c.title.] #caption(c)]
]
#let player-script = {
  let list = ready-casts.enumerate().map(((i, c)) => (
    id: "cast-" + c.name, data: read("casts/" + c.name + ".cast"),
    cols: c.cols, rows: c.rows, poster: "npt:0:" + str(c.at("poster_at", default: 2)),
  ))
  // "</" may not appear inside a script element
  let data = json.encode(list, pretty: false).replace("</", "<\\/")
  el("script", (src: "player/asciinema-player.min.js"))[]
  el("script")[#("for (const c of " + data + ") { const el = document.getElementById(c.id); el.player = AsciinemaPlayer.create({data: c.data}, el, {cols: c.cols, rows: c.rows, autoPlay: false, loop: true, fit: 'width', poster: c.poster}); }")]
}

/// Plays a recording while it is on screen and pauses it once it leaves.
/// The casts wait for it (autoPlay off) so each shows its poster frame
/// until then; the videos autoplay by themselves too.

#document(href("index"), title: "pardes", shell("index", "pardes")[
  #el("h1", (class: "masthead"))[pardes]
  #el("p", (class: "lead"))[#landing.lead]
  #el("ul", (class: "inside", "aria-label": "What's in it"))[
    #for i in landing.inside {
      let to = if i.rec != none { "#rec-" + i.rec } else { i.docs }
      el("li")[#el("a", (href: to, title: if i.rec != none { "watch it here; the docs: " + i.docs } else { "the docs" }))[#i.name]]
    }
  ]
  #el("p", (class: "credit"))[#landing.credit]
  #el("p", (class: "runs"))[#landing.status]
  #el("div", (class: "start"))[
    #for s in landing.start {
      el("a", (class: "go", href: href(s.id)))[#s.label#if s.note != none [ #el("span")[(#s.note)]]]
    }
  ]
  #el("p", (class: "rest"))[
    #for p in pages.slice(1).filter(p => p.id not in landing.start.map(s => s.id)) {
      el("a", (href: href(p.id)))[#p.title]
    }
  ]
  #el("h2", (class: "shelf"))[#landing.terminal]
  #el("div", (class: "casts"))[#for (i, c) in casts.enumerate() { cast(c, i) }]
  #el("h2", (class: "shelf"))[#landing.window]
  #el("div", (class: "clips"))[
    #for c in clips.filter(c => c.at("landing", default: true)) {
      el("figure", (class: "clip", id: "rec-" + c.name))[
        #if c.ready { video(c) } else { placeholder }
        #el("figcaption")[#caption(c)]
      ]
    }
  ]
  #el("h2", (class: "install"))[#landing.install]
  #include "../typ/install.typ"
  #if ready-casts.len() > 0 {
    el("link", (rel: "stylesheet", href: "player/asciinema-player.css"))[]
    player-script
  }
])

#for p in pages.slice(1, -1) {
  document(href(p.id), title: p.title, shell(p.id, p.title)[
    #metadata(none) #label("start-" + p.id)
    #heading(level: 1, p.title) #label("ch-" + p.id)
    #toc(p.id)
    #{
      set heading(offset: 1)
      include "../typ/" + p.file
    }
    #metadata(none) #label("end-" + p.id)
  ])
}

/// The tutor's text with its mouse buttons drawn: B1, B2, B3 and the
/// chords it writes 1-2 (hold 1, click 2) become the docs' mouse glyphs,
/// each with its hidden words, inside the preformatted block.
#let tutor-text(t) = {
  // the guide's sections by title, for "-> Guide: Modes, Config"
  let guide-sections = (:)
  for m in read("../typ/guide.typ").matches(regex("(?m)^= (.+?) <([a-z0-9-]+)>$")) {
    guide-sections.insert(m.captures.at(0), m.captures.at(1))
  }
  let tokens = regex("\\bB([123])\\b|\\b([123])-([123])\\b|docs/typ/([a-z]+)\\.typ|(?m)(?:^ -> Guide: )(.+)$|https://[^\\s)]+")
  let at = 0
  for m in t.matches(tokens) {
    t.slice(at, m.start)
    let (b, c1, c2, page, sections) = m.captures
    if b != none { btn("B" + b) }
    else if c1 != none { chord("B" + c1, "B" + c2) }
    else if page != none { link(page + ".html", m.text) }
    else if sections != none {
      " -> Guide: "
      sections.split(", ").map(name => {
        let l = guide-sections.at(name, default: none)
        if l != none { link("guide.html#" + l, name) } else { name }
      }).join(", ")
    }
    else { link(m.text, m.text) }
    at = m.end
  }
  t.slice(at)
}

#document(href("tutor"), title: "The tutor", shell("tutor", "The tutor")[
  #heading(level: 1)[The tutor] <tutor>
  The tutor as the editor shows it (#raw("Tutor"), or #raw("SPC h t")).
  #el("pre", (class: "tutor"))[#tutor-text(read(tutor-path))]
])