#let webroot = "/"

#let format-date-en(date) = {
    let months = (
        "January",
        "February",
        "March",
        "April",
        "May",
        "June",
        "July",
        "August",
        "September",
        "October",
        "November",
        "December",
    )

    [#months.at(date.month() - 1) #date.day(), #date.year()]
}

#let link-self(page, body) = {
    link(webroot + page + ".html", body)
}

#let static(path) = {
    webroot + "static/" + path
}

#let img(src) = {
    html.elem("img", attrs: (src: src, alt: ""))
}

#let post(body, title: none, author: "Paweł Redman", date: none) = {
    assert(date != none, message: "missing date")

    set document(
        title: title,
        author: "Paweł Redman",
    )

    set text(lang: "en")
    set heading(numbering: "1.1.")
    set math.equation(numbering: "(1.)")

    // As of 0.14, equations aren't supported in HTML. Emit them as SVG instead.
    show math.equation: it => context {
        if target() == "html" {
            show: if it.block { it => it } else { box }
            html.frame(it)
        } else {
            it
        }
    }

    [
        #metadata((
            title: title,
            date_year: date.year(),
            date_month: date.month(),
            date_day: date.day(),
        )) <post-meta>
    ]

    html.html({
        html.head({
            html.meta(charset: "utf-8")
            html.meta(name: "viewport", content: "width=device-width, initial-scale=1")
            html.title(title)
            html.link(rel: "stylesheet", href: static("style.css"))
        })

        html.header({
            html.nav[
                (nav element)  // TODO when there's an index page
            ]
        })

        html.main({
            html.article({
                html.header({
                    html.h1(title)
                    html.p(id: "author")[by #author, published on #html.time(datetime: date)[#format-date-en(date)]]
                })

                body
            })
        })

        html.footer[
            footer goes here
        ]
    })
}