import { describe, expect, test } from "bun:test";
import { readFileSync } from "node:fs";
import { canvasOverviewMode, resolveCanvasNodeLOD } from "../src/lib/canvas/canvas-node-lod";

describe("canvas overview rendering", () => {
    test("uses hysteresis without retaining full editors at 5%", () => {
        expect(canvasOverviewMode(0.05, false)).toBe(true);
        expect(canvasOverviewMode(0.24, false)).toBe(false);
        expect(canvasOverviewMode(0.24, true)).toBe(true);
        expect(canvasOverviewMode(0.27, true)).toBe(false);
    });
    test("keeps 5000 visible representations without 5000 business editors", () => {
        const levels = Array.from({ length: 5000 }, (_, i) => resolveCanvasNodeLOD(true, true, true, i === 23));
        expect(levels.filter((level) => level === "full")).toHaveLength(1);
        expect(levels.filter((level) => level === "preview")).toHaveLength(4999);
        expect(resolveCanvasNodeLOD(false, true, true, false)).toBe("full");
        expect(resolveCanvasNodeLOD(true, false, false, false)).toBe("shell");
        expect(resolveCanvasNodeLOD(true, false, false, true)).toBe("full");
    });
    test("wires LOD into both node kinds and the memo comparator", () => {
        const world = readFileSync(new URL("../src/pages/canvas/canvas-project-world-layers.tsx", import.meta.url), "utf8");
        const node = readFileSync(new URL("../src/components/canvas/canvas-node.tsx", import.meta.url), "utf8");
        expect(world.match(/renderLOD=\{props.nodeRenderLODById/g)).toHaveLength(2);
        expect(node).toContain("previous.renderLOD === next.renderLOD");
        expect(node).not.toContain('|| isSelected || Boolean(dragOffset) ? "full"');
    });
});