// el-html — Atomic HTML element primitives.
//
// Usage:
//   el_div("class=\"card\"", inner_html)
//   el_h1("", "Hello world")
//   el_img("/logo.png", "Logo", "width=\"120\"")
//
// Children args are raw HTML — pre-escaped by caller.
// Use el_text(s) to safely insert plain text.

// ── Text escaping ─────────────────────────────────────────────────────────────

fn el_escape(s: String) -> String {
    let s = str_replace(s, "&", "&")
    let s = str_replace(s, "<", "&lt;")
    let s = str_replace(s, ">", "&gt;")
    let s = str_replace(s, "\"", "&quot;")
    str_replace(s, "'", "&#39;")
}

fn el_text(s: String) -> String {
    el_escape(s)
}

fn el_attr(name: String, value: String) -> String {
    " " + name + "=\"" + el_escape(value) + "\""
}

// ── Block elements ────────────────────────────────────────────────────────────

fn el_div(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<div>" + children + "</div>" }
    "<div " + attrs + ">" + children + "</div>"
}

fn el_section(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<section>" + children + "</section>" }
    "<section " + attrs + ">" + children + "</section>"
}

fn el_article(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<article>" + children + "</article>" }
    "<article " + attrs + ">" + children + "</article>"
}

fn el_header(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<header>" + children + "</header>" }
    "<header " + attrs + ">" + children + "</header>"
}

fn el_footer(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<footer>" + children + "</footer>" }
    "<footer " + attrs + ">" + children + "</footer>"
}

fn el_main(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<main>" + children + "</main>" }
    "<main " + attrs + ">" + children + "</main>"
}

fn el_nav(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<nav>" + children + "</nav>" }
    "<nav " + attrs + ">" + children + "</nav>"
}

fn el_aside(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<aside>" + children + "</aside>" }
    "<aside " + attrs + ">" + children + "</aside>"
}

fn el_ul(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<ul>" + children + "</ul>" }
    "<ul " + attrs + ">" + children + "</ul>"
}

fn el_ol(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<ol>" + children + "</ol>" }
    "<ol " + attrs + ">" + children + "</ol>"
}

fn el_li(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<li>" + children + "</li>" }
    "<li " + attrs + ">" + children + "</li>"
}

fn el_p(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<p>" + children + "</p>" }
    "<p " + attrs + ">" + children + "</p>"
}

fn el_span(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<span>" + children + "</span>" }
    "<span " + attrs + ">" + children + "</span>"
}

fn el_form(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<form>" + children + "</form>" }
    "<form " + attrs + ">" + children + "</form>"
}

// ── Headings ──────────────────────────────────────────────────────────────────

fn el_h1(attrs: String, text: String) -> String {
    if str_eq(attrs, "") { return "<h1>" + el_escape(text) + "</h1>" }
    "<h1 " + attrs + ">" + el_escape(text) + "</h1>"
}

fn el_h2(attrs: String, text: String) -> String {
    if str_eq(attrs, "") { return "<h2>" + el_escape(text) + "</h2>" }
    "<h2 " + attrs + ">" + el_escape(text) + "</h2>"
}

fn el_h3(attrs: String, text: String) -> String {
    if str_eq(attrs, "") { return "<h3>" + el_escape(text) + "</h3>" }
    "<h3 " + attrs + ">" + el_escape(text) + "</h3>"
}

fn el_h4(attrs: String, text: String) -> String {
    if str_eq(attrs, "") { return "<h4>" + el_escape(text) + "</h4>" }
    "<h4 " + attrs + ">" + el_escape(text) + "</h4>"
}

// ── Interactive ───────────────────────────────────────────────────────────────

fn el_button(attrs: String, label: String) -> String {
    if str_eq(attrs, "") { return "<button type=\"button\">" + el_escape(label) + "</button>" }
    "<button type=\"button\" " + attrs + ">" + el_escape(label) + "</button>"
}

fn el_a(href: String, attrs: String, children: String) -> String {
    let h: String = "href=\"" + el_escape(href) + "\""
    if str_eq(attrs, "") { return "<a " + h + ">" + children + "</a>" }
    "<a " + h + " " + attrs + ">" + children + "</a>"
}

fn el_input(type_attr: String, attrs: String) -> String {
    if str_eq(attrs, "") { return "<input type=\"" + type_attr + "\" />" }
    "<input type=\"" + type_attr + "\" " + attrs + " />"
}

fn el_textarea(attrs: String, value: String) -> String {
    if str_eq(attrs, "") { return "<textarea>" + el_escape(value) + "</textarea>" }
    "<textarea " + attrs + ">" + el_escape(value) + "</textarea>"
}

fn el_label(for_id: String, attrs: String, children: String) -> String {
    let f: String = "for=\"" + el_escape(for_id) + "\""
    if str_eq(attrs, "") { return "<label " + f + ">" + children + "</label>" }
    "<label " + f + " " + attrs + ">" + children + "</label>"
}

// ── Media ─────────────────────────────────────────────────────────────────────

fn el_img(src: String, alt: String, attrs: String) -> String {
    let base: String = "src=\"" + el_escape(src) + "\" alt=\"" + el_escape(alt) + "\""
    if str_eq(attrs, "") { return "<img " + base + " />" }
    "<img " + base + " " + attrs + " />"
}

fn el_video(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<video>" + children + "</video>" }
    "<video " + attrs + ">" + children + "</video>"
}

// ── Inline semantic ───────────────────────────────────────────────────────────

fn el_strong(children: String) -> String {
    "<strong>" + children + "</strong>"
}

fn el_em(children: String) -> String {
    "<em>" + children + "</em>"
}

fn el_code(children: String) -> String {
    "<code>" + children + "</code>"
}

fn el_pre(attrs: String, children: String) -> String {
    if str_eq(attrs, "") { return "<pre>" + children + "</pre>" }
    "<pre " + attrs + ">" + children + "</pre>"
}

fn el_hr() -> String { "<hr />" }
fn el_br() -> String { "<br />" }

// ── Document shell ────────────────────────────────────────────────────────────

fn el_html_doc(lang: String, head_html: String, body_html: String) -> String {
    "<!doctype html><html lang=\"" + el_escape(lang) + "\"><head>"
    + head_html + "</head><body>" + body_html + "</body></html>"
}

fn el_meta(name: String, content: String) -> String {
    "<meta name=\"" + el_escape(name) + "\" content=\"" + el_escape(content) + "\" />"
}

fn el_meta_charset(charset: String) -> String {
    "<meta charset=\"" + el_escape(charset) + "\" />"
}

fn el_link_stylesheet(href: String) -> String {
    "<link rel=\"stylesheet\" href=\"" + el_escape(href) + "\" />"
}

fn el_script_src(src: String, defer_load: Bool) -> String {
    if defer_load { return "<script src=\"" + el_escape(src) + "\" defer></script>" }
    "<script src=\"" + el_escape(src) + "\"></script>"
}

fn el_script_inline(js: String) -> String {
    "<script>" + js + "</script>"
}

fn el_title(text: String) -> String {
    "<title>" + el_escape(text) + "</title>"
}

// ── Entry — smoke test ────────────────────────────────────────────────────────

let sample: String = el_div("class=\"card\"", el_h2("", "Hello") + el_p("", "World"))
println("[el-html] sample = " + sample)