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/**
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 * Lazy, guarded loader for wasm-vips (libvips compiled to WASM — the same engine
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 * as `sharp`). It's used as a progressive enhancement for high-quality (lanczos3)
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 * downscaling. Initialization is attempted once; on any failure — or in browsers
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 * without cross-origin isolation / SharedArrayBuffer — we resolve to null and the
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 * caller falls back to the canvas resampler.
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 */
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// wasm-vips ships rich types, but we treat it loosely at this dynamic boundary.
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type Vips = any;
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let vipsPromise: Promise<Vips | null> | null = null;
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function withTimeout<T>(promise: Promise<T>, ms: number, label: string): Promise<T> {
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  return new Promise<T>((resolve, reject) => {
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    const timer = setTimeout(() => reject(new Error(`${label} timed out after ${ms}ms`)), ms);
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    promise.then(
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      (value) => {
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        clearTimeout(timer);
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        resolve(value);
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      },
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      (err) => {
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        clearTimeout(timer);
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        reject(err);
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      },
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    );
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  });
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}
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export function loadVips(): Promise<Vips | null> {
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  if (vipsPromise) return vipsPromise;
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  vipsPromise = (async () => {
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    try {
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      const mod: any = await import("wasm-vips");
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      const factory = (mod.default ?? mod) as (opts?: unknown) => Promise<Vips>;
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      // dynamicLibraries: [] skips the optional HEIF/JXL/SVG modules we don't need.
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      const vips = await withTimeout(factory({ dynamicLibraries: [] }), 20_000, "wasm-vips init");
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      return vips ?? null;
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    } catch (err) {
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      console.warn("[wimp] wasm-vips unavailable — falling back to the canvas engine.", err);
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      return null;
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    }
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  })();
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  return vipsPromise;
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}