/**
* printInPlace.js — SHARED (@map/composables/printInPlace.js).
*
* ★ THE ONE print mechanism, graduated VERBATIM from my-upg-100-list/poster-wall.vue
* openPrintWindow() (commit e957cbe "Print the poster in place, on a portrait sheet") on the
* ruling that killed the pop-up path: print must happen IN PLACE — no new browser
* window, no pop-up blocker, the dialog rises over the page the user is looking at.
*
* WHY IT GRADUATES (library high bar: reusable + parameterized, 2+ consumers): the
* prayer-walk-planner's print still used window.open(), and that is not just the rejected UX --
* it is AGENT-HOSTILE. window.open() without a user gesture is pop-up-blocked, so
* PrayerWalkPlanner.print() called from an agent (an agent can also create polygons and
* trigger the print function) silently did nothing. An iframe cannot be blocked
* and needs no gesture, which is what makes the same call work for a human click AND an agent.
*
* Mechanics preserved from the poster-wall original, each for a measured reason:
* - OFF-SCREEN 1x1, not display:none — a display:none iframe does not lay out in every
* engine, and a zero-height layout can print a blank first page.
* - autoprint appends the print bootstrap AFTER the caller's markup so it runs once the
* document is parsed (matches ![]()
timing).
* - afterprint, or 60 s after the frame has LOADED, reclaims the frame, so repeated prints never
* leak nodes. A 10-minute ceiling reclaims a frame whose load never ends.
*
* Returns the frame's contentWindow, or null when the host is sandboxed/detached (caller
* keeps its own fallback).
*/
export function openPrintFrame(bodyHtml, { autoprint = false } = {}) {
const frame = document.createElement('iframe')
frame.setAttribute('aria-hidden', 'true')
frame.style.cssText = 'position:fixed;right:0;bottom:0;width:1px;height:1px;opacity:0;border:0'
document.body.appendChild(frame)
const doc = frame.contentDocument
if (!doc) { frame.remove(); return null }
doc.open()
doc.write(bodyHtml)
if (autoprint) {
doc.write(
'