Chore: Restructure Repository for SvelteKit

_old/core/ui/zoom.ts

@@ -0,0 +1,61 @@
+import { store } from "@store/state.svelte";
+
+let _appliedZoom: number = -1;
+let _vhRafId: number | null = null;
+
+export function applyZoom() {
+  const uiZoom = store.settings.uiZoom ?? 1.0;
+  if (uiZoom === _appliedZoom) return;
+  _appliedZoom = uiZoom;
+  document.documentElement.style.setProperty("--ui-zoom", String(uiZoom));
+  document.documentElement.style.setProperty("--ui-scale", String(uiZoom));
+  document.documentElement.style.zoom = `${uiZoom * 100}%`;
+  if (_vhRafId !== null) cancelAnimationFrame(_vhRafId);
+  _vhRafId = requestAnimationFrame(() => {
+    _vhRafId = null;
+    document.documentElement.style.setProperty("--visual-vh", `${window.innerHeight / uiZoom}px`);
+  });
+}
+
+export function handleZoomKey(e: KeyboardEvent) {
+  if (!e.ctrlKey) return;
+  const current = store.settings.uiZoom ?? 1.0;
+  if (e.key === "=" || e.key === "+") { e.preventDefault(); store.settings.uiZoom = Math.min(2.0, Math.round((current + 0.1) * 10) / 10); }
+  else if (e.key === "-")             { e.preventDefault(); store.settings.uiZoom = Math.max(0.5, Math.round((current - 0.1) * 10) / 10); }
+  else if (e.key === "0")             { e.preventDefault(); store.settings.uiZoom = 1.0; }
+}
+
+export function mountZoomKey(): () => void {
+  window.addEventListener("keydown", handleZoomKey);
+  return () => window.removeEventListener("keydown", handleZoomKey);
+}
+
+export function clampZoom(z: number, min: number, max: number): number {
+  return Math.round(Math.min(max, Math.max(min, z)) * 1000) / 1000;
+}
+
+export function captureZoomAnchor(
+  containerEl: HTMLElement | null,
+  style: string,
+  out: { el: HTMLElement | null; offset: number },
+) {
+  if (!containerEl || style !== "longstrip") return;
+  const containerTop = containerEl.getBoundingClientRect().top;
+  for (const img of containerEl.querySelectorAll<HTMLElement>("img[data-local-page]")) {
+    const rect = img.getBoundingClientRect();
+    if (rect.bottom > containerTop) { out.el = img; out.offset = rect.top - containerTop; return; }
+  }
+}
+
+export function restoreZoomAnchor(
+  containerEl: HTMLElement | null,
+  out: { el: HTMLElement | null; offset: number },
+) {
+  if (!out.el || !containerEl) return;
+  const el = out.el;
+  out.el = null;
+  requestAnimationFrame(() => {
+    const containerTop = containerEl!.getBoundingClientRect().top;
+    containerEl!.scrollTop += (el.getBoundingClientRect().top - containerTop) - out.offset;
+  });
+}