import gleam/dict
import gleam/list
import gleam/option
import kielet.{gettext as g_}
import lustre/attribute.{attribute, href, id, name, rel, role, type_}
import lustre/element.{type Element, text}
import lustre/element/html.{
  a, body, footer, h1, head, header, html, li, link, main, meta, nav, p, section,
  title, ul,
}
import scriptorium/config.{type Configuration}
import scriptorium/models/database.{type Database}
import scriptorium/models/menu.{type MenuItem}
import scriptorium/rendering/views/archives
import scriptorium/rendering/views/tags

/// The base view pre-renders some content once, so that it can be reused for every render.
pub type PreRendered {
  PreRendered(tags: Element(Nil), archives: Element(Nil))
}

pub fn generate(db: Database, config: Configuration) {
  let pre_rendered = pre_render(db, config, tags.view, archives.view)
  fn(inner: Element(Nil), extra_meta: List(Element(Nil)), title_prefix: String) {
    view(db, config, pre_rendered, inner, extra_meta, title_prefix)
  }
}

/// Pre-render the tag and archive elements using the given tags and archives
/// components.
pub fn pre_render(
  db: Database,
  config: Configuration,
  tags: fn(Database, Configuration) -> Element(Nil),
  archives: fn(Database, Configuration) -> Element(Nil),
) -> PreRendered {
  PreRendered(tags: tags(db, config), archives: archives(db, config))
}

fn view(
  db: Database,
  config: Configuration,
  pre_rendered: PreRendered,
  inner: Element(Nil),
  extra_meta: List(Element(Nil)),
  title_prefix: String,
) {
  let title_text = case title_prefix {
    "" -> config.blog_name
    prefix -> prefix <> " · " <> config.blog_name
  }

  html([attribute("lang", config.l10n.language)], [
    head([], [
      meta([attribute("charset", "utf-8")]),
      meta([
        name("viewport"),
        attribute("content", "width=device-width, initial-scale=1"),
      ]),
      title([], title_text),
      link([href(config.paths.root <> "/css/normalize.css"), rel("stylesheet")]),
      link([href(config.paths.root <> "/css/magick.css"), rel("stylesheet")]),
      link([href(config.paths.root <> "/css/custom.css"), rel("stylesheet")]),
      link([
        href(config.paths.root <> config.paths.feed),
        rel("alternate"),
        type_("application/atom+xml"),
      ]),
      case config.author.url {
        option.Some(url) -> link([rel("me"), href(url)])
        _ -> element.none()
      },
      ..extra_meta
    ]),
    body([], [
      header([id("title"), role("banner")], [
        h1([], [
          a([href(config.paths.html(config.paths.root <> config.paths.index))], [
            text(config.blog_name),
          ]),
        ]),
        case database.menu(db) {
          [] -> element.none()
          m -> menu(m)
        },
      ]),
      main([], [inner]),
      section([id("sidebar")], [
        case dict.size(database.tags(db)) {
          0 -> element.none()
          _ ->
            nav(
              [
                id("tags"),
                attribute("aria-label", g_(config.l10n.context, "Tags")),
              ],
              [pre_rendered.tags],
            )
        },
        nav(
          [
            id("archives"),
            attribute("aria-label", g_(config.l10n.context, "Archives")),
          ],
          [pre_rendered.archives],
        ),
      ]),
      footer([], [
        p([], [
          text(config.rendering.copyright),
          text(" · "),
          text("Powered by: "),
          a([href("https://gleam.run/")], [text("Gleam")]),
          text(", "),
          a([href("https://hexdocs.pm/lustre")], [text("Lustre")]),
          text(", "),
          a([href("https://gitlab.com/Nicd/scriptorium")], [text("Scriptorium")]),
        ]),
      ]),
    ]),
  ])
}

fn menu(menu: List(MenuItem)) {
  nav([], [
    ul(
      [],
      list.map(menu, fn(item) {
        li([], [a([href(item.url)], [text(item.name)])])
      }),
    ),
  ])
}