Initial release of Barcode Tools 0.1.0

src/barcode/payloads.ts

@@ -0,0 +1,102 @@
+export type PayloadKind =
+  "text" | "url" | "email" | "sms" | "wifi" | "vcard" | "geo";
+
+export interface PayloadFields {
+  primary: string;
+  secondary?: string;
+  tertiary?: string;
+  hidden?: boolean;
+}
+
+function escapeWifi(value: string): string {
+  return value.replace(/[\\;,:"]/gu, (character) => `\\${character}`);
+}
+
+function escapeVcard(value: string): string {
+  return value
+    .replaceAll("\\", "\\\\")
+    .replaceAll("\n", "\\n")
+    .replaceAll(";", "\\;")
+    .replaceAll(",", "\\,");
+}
+
+export function buildStructuredPayload(
+  kind: PayloadKind,
+  fields: PayloadFields,
+): string {
+  const primary = fields.primary.trim();
+  if (!primary) throw new Error("The primary value is required.");
+  switch (kind) {
+    case "text":
+      return fields.primary;
+    case "url": {
+      const url = new URL(primary);
+      if (!["http:", "https:"].includes(url.protocol))
+        throw new Error("The URL builder accepts HTTP and HTTPS URLs only.");
+      return url.href;
+    }
+    case "email":
+      return `mailto:${encodeURIComponent(primary)}${fields.secondary ? `?subject=${encodeURIComponent(fields.secondary)}` : ""}`;
+    case "sms":
+      return `SMSTO:${primary}:${fields.secondary ?? ""}`;
+    case "wifi": {
+      const supplied = (fields.tertiary || "WPA").trim();
+      if (!/^(?:WPA|WEP|nopass)$/iu.test(supplied))
+        throw new Error("Wi-Fi security must be WPA, WEP, or nopass.");
+      const security =
+        supplied.toLowerCase() === "nopass" ? "nopass" : supplied.toUpperCase();
+      return `WIFI:T:${security};S:${escapeWifi(primary)};P:${escapeWifi(fields.secondary ?? "")};H:${fields.hidden ? "true" : "false"};;`;
+    }
+    case "vcard":
+      return [
+        "BEGIN:VCARD",
+        "VERSION:3.0",
+        `FN:${escapeVcard(primary)}`,
+        fields.secondary ? `TEL:${escapeVcard(fields.secondary)}` : "",
+        fields.tertiary ? `EMAIL:${escapeVcard(fields.tertiary)}` : "",
+        "END:VCARD",
+      ]
+        .filter(Boolean)
+        .join("\r\n");
+    case "geo": {
+      const latitude = Number(primary);
+      const longitude = Number(fields.secondary);
+      if (
+        !Number.isFinite(latitude) ||
+        latitude < -90 ||
+        latitude > 90 ||
+        !Number.isFinite(longitude) ||
+        longitude < -180 ||
+        longitude > 180
+      )
+        throw new Error("Latitude must be −90…90 and longitude −180…180.");
+      return `geo:${latitude},${longitude}`;
+    }
+  }
+}
+
+export function gtinCheckDigit(body: string): number {
+  if (!/^\d{1,17}$/u.test(body))
+    throw new Error("A GTIN body must contain 1–17 decimal digits.");
+  let sum = 0;
+  for (
+    let index = body.length - 1, position = 0;
+    index >= 0;
+    index -= 1, position += 1
+  )
+    sum += Number(body[index]) * (position % 2 === 0 ? 3 : 1);
+  return (10 - (sum % 10)) % 10;
+}
+
+export function validateGtin(value: string): {
+  valid: boolean;
+  expected: string;
+} {
+  if (![8, 12, 13, 14].includes(value.length) || !/^\d+$/u.test(value))
+    return {
+      valid: false,
+      expected: "GTIN length must be 8, 12, 13, or 14 digits.",
+    };
+  const expected = String(gtinCheckDigit(value.slice(0, -1)));
+  return { valid: value.endsWith(expected), expected };
+}