Barcode

import ui/theme.qwe use theme_cssuse ui/barcode.qweroute GET / = <html><head><style>{theme_css}</style></head><body class="ui-root">...</body></html>

component BarcodeDemoLive() {    state text = "Hello 2026"    <div.demo-stack style="justify-items: start">        <label style="display: grid; gap: 4px; font-size: 13px; width: min(320px, 100%)">Text to encode            <input id="barcode-demo-input" value={text} @input={(e) => { text = e.value }}                   style="height: 34px; padding: 0 10px; border: 1px solid var(--ui-border); border-radius: var(--ui-radius-sm); background: var(--ui-surface); color: var(--ui-fg); font: inherit"/>        </label>        <Barcode id="barcode-demo-live" text={text}/>        <p.demo-note>{len(barcode_values(text))} symbols, drawn in the browser as you type.</p>    </div>}view BarcodeDemo() =    <div.demo-stack>        <div.demo-row style="align-items: flex-end; gap: 28px">            <Barcode id="barcode-demo-ticket" text="QA204-LHR-OPO"/>            <Barcode id="barcode-demo-digits" text="0012345678905" bar={1.5} height={48}/>            <Barcode id="barcode-demo-bare" text="Order 98765" show_text={false} height={40} themed={true} label="Order number"/>        </div>        <BarcodeDemoLive/>    </div>

// Barcode: a Code 128 barcode as SVG from text: an order number, a parcel's label,// a ticket's code. The encoder is written here in Quillo (no library), so it draws// the same on the server and in the browser. It uses code set B for text and// switches to code set C (two digits a bar pattern) for runs of four digits or// more, so long numbers stay short; the check symbol is the standard's (mod 103).////   <Barcode text="QA204-LHR-OPO"/>//   <Barcode text="0012345678905" bar={1.5} height={48} show_text={false}/>//// text: what it encodes: printable ASCII (space to ~); another character is// written as "?". bar: the width of the narrowest bar in px (2). height: the bars'// height in px (64). show_text: the text written under it (true). label: what// screen readers hear ("Barcode: " and the text by default). quiet: the light// margin at each end, in narrow bars (10, as the standard asks). themed: false// (default) keeps it dark on light whatever the page's theme; true follows it.// barcode_values(text) gives the symbols' values (start, data, check, stop) and// barcode_modules(text) the bars as a string of 1 (bar) and 0 (space).import ui/theme.qwe use ui_clslet barcode_css = css`.ui-barcode { display: inline-grid; justify-items: center; gap: 4px; max-width: 100%; margin: 0; padding: 6px 0 4px;  background: var(--ui-surface); color: var(--ui-fg); border-radius: 4px; font: 13px/1.2 var(--ui-mono); }.ui-barcode svg { display: block; max-width: 100%; }.ui-barcode figcaption { letter-spacing: .12em; white-space: pre; }`// The patterns of values 0 to 105 (11 modules each, 1 a bar), and the stop's (13).let barcode_patterns = [    "11011001100", "11001101100", "11001100110", "10010011000", "10010001100", "10001001100", "10011001000", "10011000100",    "10001100100", "11001001000", "11001000100", "11000100100", "10110011100", "10011011100", "10011001110", "10111001100",    "10011101100", "10011100110", "11001110010", "11001011100", "11001001110", "11011100100", "11001110100", "11101101110",    "11101001100", "11100101100", "11100100110", "11101100100", "11100110100", "11100110010", "11011011000", "11011000110",    "11000110110", "10100011000", "10001011000", "10001000110", "10110001000", "10001101000", "10001100010", "11010001000",    "11000101000", "11000100010", "10110111000", "10110001110", "10001101110", "10111011000", "10111000110", "10001110110",    "11101110110", "11010001110", "11000101110", "11011101000", "11011100010", "11011101110", "11101011000", "11101000110",    "11100010110", "11101101000", "11101100010", "11100011010", "11101111010", "11001000010", "11110001010", "10100110000",    "10100001100", "10010110000", "10010000110", "10000101100", "10000100110", "10110010000", "10110000100", "10011010000",    "10011000010", "10000110100", "10000110010", "11000010010", "11001010000", "11110111010", "11000010100", "10001111010",    "10100111100", "10010111100", "10010011110", "10111100100", "10011110100", "10011110010", "11110100100", "11110010100",    "11110010010", "11011011110", "11011110110", "11110110110", "10101111000", "10100011110", "10001011110", "10111101000",    "10111100010", "11110101000", "11110100010", "10111011110", "10111101110", "11101011110", "11110101110", "11010000100",    "11010010000", "11010011100", "1100011101011",]let barcode_ascii = " !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~"// How many digits run from place i.fn barcode_digits(chars: list, i: int) -> int {    let n = 0    while i + n < len(chars) && contains("0123456789", chars[i + n]) { n = n + 1 }    n}// The values of the symbols: start, data (in set B or C), check symbol, stop.fn barcode_values(text: str) -> list {    let chars = split(text, "") | map((c) => index_of(barcode_ascii, c) != null ? c : "?")    let lead = barcode_digits(chars, 0)    let c_first = len(chars) >= 2 && lead % 2 == 0 && (lead >= 4 || lead == len(chars))    let out = [c_first ? 105 : 104]    let in_c = c_first    let i = 0    while i < len(chars) {        let run = barcode_digits(chars, i)        if in_c {            if run >= 2 {                out = push(out, int(chars[i] + chars[i + 1]))                i = i + 2            } else {                out = push(out, 100)                in_c = false            }        } else if run >= 4 && run % 2 == 0 {            out = push(out, 99)            in_c = true        } else {            out = push(out, index_of(barcode_ascii, chars[i]))            i = i + 1        }    }    let check = (out[0] + sum(for [k, v] in enumerate(drop(out, 1)) => (k + 1) * v)) % 103    push(push(out, check), 106)}// The bars and spaces of a text, as a string of 1 and 0.fn barcode_modules(text: str) -> str = join(barcode_values(text) | map((v) => barcode_patterns[v]), "")view Barcode(text: str, bar: num = 2, height: int = 64, show_text: bool = true, label: str? = null, quiet: int = 10,             themed: bool = false, id: str? = null, class: str? = null) {    style global barcode_css    let mods = barcode_modules(text)    let total = len(mods) + 2 * quiet    // Written as the browser would: 396, not 396.0.    let w = round(total * bar * 10) / 10    let width = w == floor(w) ? str(floor(w)) : str(w)    let d = join(re.find_all(mods, "1+") | map((m) => `M${m.start + quiet} 0h${len(m.text)}v1h-${len(m.text)}z`), "")    <figure class={ui_cls(["ui-barcode", !themed && "ui-light", class])} id={id}>        <svg width={width} height={height} viewBox={`0 0 ${total} 1`} preserveAspectRatio="none" role="img"             aria-label={label ?? `Barcode: ${text}`} shape-rendering="crispEdges">            <path fill="currentColor" d={d}/>        </svg>        {show_text && <figcaption aria-hidden="true">{text}</figcaption>}    </figure>}