Massive refactor.

inventory/static/js/components/grid/encode-decode.js

@@ -0,0 +1,438 @@
+import { SHAPE_DEFAULTS } from "./widget-core.js";
+
+function shortenKeys(shapes) {
+    const keyMap = {
+        type: 't',
+        points: 'p',
+        color: 'cl',          // avoid collision with x2
+        strokeWidth: 'sw',
+        strokeOpacity: 'so',
+        fillOpacity: 'fo',
+        fill: 'f',
+
+        x: 'x',
+        y: 'y',
+        w: 'w',
+        h: 'h',
+
+        x1: 'a',
+        y1: 'b',
+        x2: 'c',
+        y2: 'd'
+    };
+
+    return shapes.map((shape) => {
+        const out = {};
+        for (const key of Object.keys(shape)) {
+            const newKey = keyMap[key] || key;
+            out[newKey] = shape[key];
+        }
+        return out;
+    });
+}
+
+function shortenShapes(shapes) {
+    const shapeMap = { path: 'p', line: 'l', rect: 'r', ellipse: 'e', stateChange: 's' };
+    return shapes.map(shape => ({
+        ...shape,
+        type: shapeMap[shape.type] || shape.type
+    }));
+}
+
+function collapseStateChanges(shapes) {
+    const out = [];
+    let pending = null;
+
+    const flush = () => {
+        if (pending) out.push(pending);
+        pending = null;
+    };
+
+    for (const shape of shapes) {
+        if (shape.type === "stateChange") {
+            if (!pending) pending = { ...shape };
+            else {
+                for (const [k, v] of Object.entries(shape)) {
+                    if (k !== "type") pending[k] = v;
+                }
+            }
+            continue;
+        }
+
+        flush();
+        out.push(shape);
+    }
+
+    flush();
+    return out;
+}
+
+function stateCode(shapes, SHAPE_DEFAULTS) {
+    const state = {
+        ...SHAPE_DEFAULTS,
+        color: "#000000",
+        fill: false,
+        fillOpacity: 1
+    };
+
+    const styleKeys = Object.keys(state);
+    const out = [];
+
+    for (const shape of shapes) {
+        const s = { ...shape };
+        const stateChange = {};
+
+        for (const key of styleKeys) {
+            if (!(key in s)) continue;
+
+            if (s[key] !== state[key]) {
+                stateChange[key] = s[key];
+                state[key] = s[key];
+            }
+
+            delete s[key];
+        }
+
+        if (Object.keys(stateChange).length > 0) {
+            out.push({ type: "stateChange", ...stateChange });
+        }
+
+        out.push(s);
+    }
+
+    return out;
+}
+
+function computeDeltas(shapes) {
+    const q = 100;
+
+    const out = [];
+    let prevKind = null;
+
+    let prevBR = null;
+
+    let prevLineEnd = null;
+
+    const MAX_DOC_COORD = 1_000_000;
+    const MAX_INT = MAX_DOC_COORD * q;
+
+    const clampInt = (v) => {
+        if (!Number.isFinite(v)) return 0;
+        if (v > MAX_INT) return MAX_INT;
+        if (v < -MAX_INT) return -MAX_INT;
+        return v;
+    };
+
+    const toInt = (n) => clampInt(Math.round(Number(n) * q));
+
+    const resetRun = () => {
+        prevKind = null;
+        prevBR = null;
+        prevLineEnd = null;
+    };
+
+    for (const shape of shapes) {
+        if (shape.type === "stateChange") {
+            out.push(shape);
+            resetRun();
+            continue;
+        }
+
+        if (shape.type === "path") {
+            const s = { ...shape };
+            if (!Array.isArray(s.points) || s.points.length === 0) {
+                out.push(s);
+                resetRun();
+                continue;
+            }
+
+            const pts = [toInt(s.points[0].x), toInt(s.points[0].y)];
+            let prev = s.points[0];
+            for (let i = 1; i < s.points.length; i++) {
+                const cur = s.points[i];
+                pts.push(toInt(cur.x - prev.x), toInt(cur.y - prev.y));
+                prev = cur;
+            }
+            s.points = pts;
+            out.push(s);
+            resetRun();
+            continue;
+        }
+
+        if (shape.type === "line") {
+            const s = { ...shape };
+
+            const x1 = toInt(s.x1), y1 = toInt(s.y1);
+            const x2 = toInt(s.x2), y2 = toInt(s.y2);
+
+            let arr;
+            if (prevKind !== "line" || !prevLineEnd) {
+                arr = [x1, y1, x2 - x1, y2 - y1];
+            } else {
+                arr = [x1 - prevLineEnd.x2, y1 - prevLineEnd.y2, x2 - x1, y2 - y1];
+            }
+
+            prevKind = "line";
+            prevLineEnd = { x2, y2 };
+
+            delete s.x1; delete s.y1; delete s.x2; delete s.y2;
+            s.points = arr;
+            out.push(s);
+            continue;
+        }
+
+        if (shape.type === "rect" || shape.type === "ellipse") {
+            const s = { ...shape };
+
+            const x = toInt(s.x), y = toInt(s.y);
+            const w = toInt(s.w), h = toInt(s.h);
+
+            let arr;
+            if (prevKind !== s.type || !prevBR) {
+                arr = [x, y, w, h];
+            } else {
+                arr = [x - prevBR.x, y - prevBR.y, w, h];
+            }
+
+            prevKind = s.type;
+            prevBR = { x: x + w, y: y + h };
+
+            delete s.x; delete s.y; delete s.w; delete s.h;
+            s.points = arr;
+            out.push(s);
+            continue;
+        }
+
+        out.push(shape);
+        resetRun();
+    }
+
+    return out;
+}
+
+function encodeRuns(shapes) {
+    const out = [];
+    let run = null;
+
+    const flush = () => {
+        if (!run) return;
+        out.push(run);
+        run = null;
+    };
+
+    for (const shape of shapes) {
+        if (shape.type === 'path' || shape.type === 'stateChange') {
+            flush();
+            out.push(shape);
+            continue;
+        }
+
+        if (!run) {
+            run = { ...shape, points: [...shape.points] };
+            continue;
+        }
+
+        if (shape.type === run.type) {
+            run.points.push(...shape.points);
+        } else {
+            flush();
+            run = { ...shape, points: [...shape.points] };
+        }
+    }
+
+    flush();
+    return out;
+}
+
+function encodeStates(shapes) {
+    return shapes.map(shape => {
+        if (shape.type !== 'stateChange') return shape;
+        const re = /^#([0-9a-fA-F]{3}|[0-9a-fA-F]{6})$/;
+
+        let newShape = {};
+        Object.keys(shape).forEach(key => {
+            if (key === 'strokeOpacity' || key === 'strokeWidth' || key === 'fillOpacity') {
+                const v = Number(shape[key]);
+                if (Number.isFinite(v))
+                    newShape[key] = Math.round(v * 100);
+            } else if (key === 'color') {
+                newShape[key] = re.test(shape[key]) ? shape[key] : '#000000';
+            } else if (key === 'fill') {
+                newShape[key] = !!shape[key];
+            }
+        });
+        return { ...shape, ...newShape };
+    });
+}
+
+export function encode({ cellSize, shapes, stripCaches, SHAPE_DEFAULTS }) {
+    if (!SHAPE_DEFAULTS) SHAPE_DEFAULTS = { strokeWidth: 0.12, strokeOpacity: 1, fillOpacity: 1 };
+
+    const cs = Number(cellSize);
+    const safeCellSize = Number.isFinite(cs) && cs >= 1 ? cs : 25;
+
+    const safeShapes = Array.isArray(shapes) ? shapes : [];
+    const stripped = (typeof stripCaches === "function") ? stripCaches(safeShapes) : safeShapes;
+
+    const payload = {
+        v: 1,
+        cs: safeCellSize,
+        q: 100,
+        d: {
+            cl: "#000000",
+            f: false,
+            sw: 12,
+            so: 100,
+            fo: 100
+        },
+        s: shortenKeys(
+            shortenShapes(
+                encodeStates(
+                    encodeRuns(
+                        computeDeltas(
+                            collapseStateChanges(
+                                stateCode(stripped, SHAPE_DEFAULTS)
+                            )
+                        )
+                    )
+                )
+            )
+        )
+    };
+    return payload;
+}
+
+
+function decodePath(arr, q) {
+    let x = arr[0], y = arr[1];
+    const pts = [{ x: x / q, y: y / q }];
+    for (let i = 2; i < arr.length; i += 2) {
+        x += arr[i];
+        y += arr[i + 1];
+        pts.push({ x: x / q, y: y / q });
+    }
+    return pts;
+}
+
+export function decode(doc) {
+    const q = Number(doc?.q) || 100;
+    const cs = Number(doc?.cs) || 25;
+
+    const defaults = doc?.d || {};
+    const state = {
+        color: defaults.cl ?? "#000000",
+        fill: !!defaults.f,
+        strokeWidth: (Number(defaults.sw) ?? 12) / 100,
+        strokeOpacity: (Number(defaults.so) ?? 100) / 100,
+        fillOpacity: (Number(defaults.fo) ?? 100) / 100
+    };
+
+    const outShapes = [];
+
+    const num01 = (v, fallback) => {};
+
+    const applyStateChange = (op) => {
+        if ("cl" in op) state.color = op.cl;
+        if ("f" in op) state.fill = !!op.f;
+        if ("sw" in op) state.strokeWidth = num01(op.sw, state.strokeWidth * 100) / 100;
+        if ("so" in op) state.strokeOpacity = num01(op.so, state.strokeOpacity * 100) / 100;
+        if ("fo" in op) state.fillOpacity = num01(op.fo, state.fillOpacity * 100) / 100;
+    };
+
+    const ops = Array.isArray(doc?.s) ? doc.s : [];
+    for (const op of ops) {
+        if (!op || typeof op !== "object") continue;
+
+        const t = op.t;
+        if (t === "s") {
+            applyStateChange(op);
+            continue;
+        }
+
+        const arr = op.p;
+        if (!Array.isArray(arr) || arr.length === 0) continue;
+
+        if (t === "p") {
+            if (arr.length < 2 || (arr.length % 2) !== 0) continue;
+
+            outShapes.push({
+                type: "path",
+                points: decodePath(arr, q),
+                color: state.color,
+                strokeWidth: state.strokeWidth,
+                strokeOpacity: state.strokeOpacity
+            });
+            continue;
+        }
+
+        if ((arr.length % 4) !== 0) continue;
+
+        if (t === "l") {
+            let prevX2 = null, prevY2 = null;
+
+            for (let i = 0; i < arr.length; i += 4) {
+                const a = arr[i], b = arr[i + 1], c = arr[i + 2], d = arr[i + 3];
+
+                let x1, y1;
+                if (i === 0) {
+                    x1 = a; y1 = b;
+                } else {
+                    x1 = prevX2 + a;
+                    y1 = prevY2 + b;
+                }
+
+                const x2 = x1 + c;
+                const y2 = y1 + d;
+
+                outShapes.push({
+                    type: "line",
+                    x1: x1 / q, y1: y1 / q, x2: x2 / q, y2: y2 / q,
+                    color: state.color,
+                    strokeWidth: state.strokeWidth,
+                    strokeOpacity: state.strokeOpacity
+                });
+
+                prevX2 = x2; prevY2 = y2;
+            }
+            continue;
+        }
+
+        if (t === "r" || t === "e") {
+            let prevBRx = null, prevBRy = null;
+
+            for (let i = 0; i < arr.length; i += 4) {
+                const a = arr[i], b = arr[i + 1], c = arr[i + 2], d = arr[i + 3];
+
+                let x, y;
+                if (i === 0) {
+                    x = a; y = b;
+                } else {
+                    x = prevBRx + a;
+                    y = prevBRy + b;
+                }
+
+                const w = c, h = d;
+
+                outShapes.push({
+                    type: (t === "r") ? "rect" : "ellipse",
+                    x: x / q, y: y / q, w: w / q, h: h / q,
+                    color: state.color,
+                    fill: state.fill,
+                    fillOpacity: state.fillOpacity,
+                    strokeWidth: state.strokeWidth,
+                    strokeOpacity: state.strokeOpacity
+                });
+
+                prevBRx = x + w;
+                prevBRy = y + h;
+            }
+            continue;
+        }
+    }
+
+    return {
+        version: Number(doc?.v) || 1,
+        cellSize: cs,
+        shapes: outShapes
+    };
+}

inventory/static/js/components/grid/geometry.js

@@ -0,0 +1,117 @@
+export function dist2(a, b) {
+    const dx = a.x - b.x, dy = a.y - b.y;
+    return dx * dx + dy * dy;
+}
+
+export function pointToSegmentDist2(p, a, b) {
+    const vx = b.x - a.x, vy = b.y - a.y;
+    const wx = p.x - a.x, wy = p.y - a.y;
+
+    const c1 = vx * wx + vy * wy;
+    if (c1 <= 0) return dist2(p, a);
+
+    const c2 = vx * vx + vy * vy;
+    if (c2 <= c1) return dist2(p, b);
+
+    const t = c1 / c2;
+    const proj = { x: a.x + t * vx, y: a.y + t * vy };
+    return dist2(p, proj);
+}
+
+function hitShape(p, s, tol) {
+    if (s.type === 'line') {
+        const a = { x: s.x1, y: s.y1 };
+        const b = { x: s.x2, y: s.y2 };
+        const sw = Math.max(0, Number(s.strokeWidth) || 0) / 2;
+        const t = tol + sw;
+        return pointToSegmentDist2(p, a, b) <= (t * t);
+    }
+
+    if (s.type === 'path') {
+        const pts = (s.renderPoints?.length >= 2) ? s.renderPoints : s.points;
+        if (!pts || pts.length < 2) return false;
+
+        const sw = Math.max(0, Number(s.strokeWidth) || 0) / 2;
+        const t = tol + sw;
+
+        for (let i = 0; i < pts.length - 1; i++) {
+            if (pointToSegmentDist2(p, pts[i], pts[i + 1]) <= (t * t)) return true;
+        }
+        return false;
+    }
+
+    if (s.type === 'rect') {
+        return hitRect(p, s, tol);
+    }
+
+    if (s.type === 'ellipse') {
+        return hitEllipse(p, s, tol);
+    }
+
+    return false;
+}
+
+function hitRect(p, r, tol) {
+    const x1 = r.x, y1 = r.y, x2 = r.x + r.w, y2 = r.y + r.h;
+    const minX = Math.min(x1, x2), maxX = Math.max(x1, x2);
+    const minY = Math.min(y1, y2), maxY = Math.max(y1, y2);
+
+    const inside = (p.x >= minX && p.x <= maxX && p.y >= minY && p.y <= maxY);
+
+    if (r.fill) {
+        return (p.x >= minX - tol && p.x <= maxX + tol && p.y >= minY - tol && p.y <= maxY + tol);
+    }
+
+    if (!inside) {
+        if (p.x < minX - tol || p.x > maxX + tol || p.y < minY - tol || p.y > maxY + tol) return false;
+    }
+
+    const nearLeft = Math.abs(p.x - minX) <= tol && p.y >= minY - tol && p.y <= maxY + tol;
+    const nearRight = Math.abs(p.x - maxX) <= tol && p.y >= minY - tol && p.y <= maxY + tol;
+    const nearTop = Math.abs(p.y - minY) <= tol && p.x >= minX - tol && p.x <= maxX + tol;
+    const nearBottom = Math.abs(p.y - maxY) <= tol && p.x >= minX - tol && p.x <= maxX + tol;
+
+    return nearLeft || nearRight || nearTop || nearBottom;
+}
+
+function hitEllipse(p, e, tol) {
+    const cx = e.x + e.w / 2;
+    const cy = e.y + e.h / 2;
+    const rx = Math.abs(e.w / 2);
+    const ry = Math.abs(e.h / 2);
+    if (rx <= 0 || ry <= 0) return false;
+
+    const nx = (p.x - cx) / rx;
+    const ny = (p.y - cy) / ry;
+    const d = nx * nx + ny * ny;
+
+    if (e.fill) {
+        const rx2 = (rx + tol);
+        const ry2 = (ry + tol);
+        const nnx = (p.x - cx) / rx2;
+        const nny = (p.y - cy) / ry2;
+        return (nnx * nnx + nny * nny) <= 1;
+    }
+
+    const minR = Math.max(1e-6, Math.min(rx, ry));
+    const band = tol / minR;
+    return Math.abs(d - 1) <= Math.max(0.02, band);
+}
+
+export function pickShapeAt(docPt, shapes, cellSize, opts = {}) {
+    const pxTol = opts.pxTol ?? 6;
+    const cs = Number(cellSize);
+    const safeCellSize = (Number.isFinite(cs) && cs > 0) ? cs : 25;
+
+    const tol = pxTol / safeCellSize;
+
+    for (let i = shapes.length - 1; i >= 0; i--) {
+        const s = shapes[i];
+        if (!s) continue;
+
+        if (hitShape(docPt, s, tol)) {
+            return { index: i, shape: s };
+        }
+    }
+    return null;
+}

inventory/static/js/components/grid/global-bindings.js

@@ -0,0 +1,23 @@
+(function bindGridGlobalOnce() {
+    if (window.__gridGlobalBound) return;
+    window.__gridGlobalBound = true;
+
+    window.activeGridWidget = null;
+
+    // Keydown (undo/redo, escape)
+    document.addEventListener('keydown', (e) => {
+        const w = window.activeGridWidget;
+        if (!w || typeof w.handleKeyDown !== 'function') return;
+        w.handleKeyDown(e);
+    });
+
+    // Pointer finalize (for drawing finishing outside the element)
+    const forwardPointer = (e) => {
+        const w = window.__gridPointerOwner || window.activeGridWidget;
+        if (!w || typeof w.handleGlobalPointerUp !== 'function') return;
+        w.handleGlobalPointerUp(e);
+    };
+
+    window.addEventListener('pointerup', forwardPointer, { capture: true });
+    window.addEventListener('pointercancel', forwardPointer, { capture: true });
+})();

inventory/static/js/components/grid/index.js

@@ -0,0 +1,46 @@
+import './global-bindings.js';
+import { initGridWidget } from './widget-init.js';
+
+const GRID_BOOT = window.__gridBootMap || (window.__gridBootMap = new WeakMap());
+
+(function autoBootGridWidgets() {
+    function bootRoot(root) {
+        if (GRID_BOOT.has(root)) return;
+        GRID_BOOT.set(root, true);
+
+        const mode = root.dataset.mode || 'editor';
+        const storageKey = root.dataset.storageKey || root.dataset.key || 'gridDoc';
+
+        const api = initGridWidget(root, { mode, storageKey });
+        root.__gridApi = api;
+    }
+
+    document.querySelectorAll('[data-grid-widget]').forEach(bootRoot);
+
+    const mo = new MutationObserver((mutations) => {
+        for (const m of mutations) {
+            for (const node of m.removedNodes) {
+                if (!(node instanceof Element)) continue;
+
+                const roots = [];
+                if (node.matches?.('[data-grid-widget]')) roots.push(node);
+                node.querySelectorAll?.('[data-grid-widget]').forEach(r => roots.push(r));
+
+                for (const r of roots) {
+                    r.__gridApi?.destroy?.();
+                    r.__gridApi = null;
+                    GRID_BOOT.delete(r);
+                }
+            }
+
+            for (const node of m.addedNodes) {
+                if (!(node instanceof Element)) continue;
+
+                if (node.matches?.('[data-grid-widget]')) bootRoot(node);
+                node.querySelectorAll?.('[data-grid-widget]').forEach(bootRoot);
+            }
+        }
+    });
+
+    mo.observe(document.documentElement, { childList: true, subtree: true });
+})();

inventory/static/js/components/grid/simplify.js

@@ -0,0 +1,42 @@
+import { pointToSegmentDist2 } from './geometry.js';
+
+export function simplifyRDP(points, epsilon) {
+    if (!Array.isArray(points) || points.length < 3) return points || [];
+    const e = Number(epsilon);
+    const eps2 = Number.isFinite(e) ? e * e : 0;
+
+    function rdp(first, last, out) {
+        let maxD2 = 0;
+        let idx = -1;
+
+        const a = points[first];
+        const b = points[last];
+
+        for (let i = first + 1; i < last; ++i) {
+            const d2 = pointToSegmentDist2(points[i], a, b);
+            if (d2 > maxD2) {
+                maxD2 = d2;
+                idx = i;
+            }
+        }
+
+        if (maxD2 > eps2 && idx !== -1) {
+            rdp(first, idx, out);
+            out.pop();
+            rdp(idx, last, out);
+        } else {
+            out.push(a, b);
+        }
+    }
+
+    const out = [];
+    rdp(0, points.length - 1, out);
+
+    const deduped = [out[0]];
+    for (let i = 1; i < out.length; i++) {
+        const prev = deduped[deduped.length - 1];
+        const cur = out[i];
+        if (prev.x !== cur.x || prev.y !== cur.y) deduped.push(cur);
+    }
+    return deduped;
+}

inventory/static/js/components/grid/spline.js

@@ -0,0 +1,90 @@
+export function catmullRomResample(points, {
+    alpha = 0.5,
+    samplesPerSeg = 8,
+    maxSamplesPerSeg = 32,
+    minSamplesPerSeg = 4,
+    closed = false,
+    maxOutputPoints = 5000
+} = {}) {
+    if (!Array.isArray(points) || points.length < 2) return points || [];
+
+    const dist = (a, b) => {
+        const dx = b.x - a.x, dy = b.y - a.y;
+        return Math.hypot(dx, dy);
+    };
+
+    const tj = (ti, pi, pj) => ti + Math.pow(dist(pi, pj), alpha);
+
+    const lerp2 = (a, b, t) => ({ x: a.x + (b.x - a.x) * t, y: a.y + (b.y - a.y) * t });
+
+    function evalSegment(p0, p1, p2, p3, t) {
+        let t0 = 0;
+        let t1 = tj(t0, p0, p1);
+        let t2 = tj(t1, p1, p2);
+        let t3 = tj(t2, p2, p3);
+
+        const eps = 1e-6;
+        if (t1 - t0 < eps) t1 = t0 + eps;
+        if (t2 - t1 < eps) t2 = t1 + eps;
+        if (t3 - t2 < eps) t3 = t2 + eps;
+
+        const u = t1 + (t2 - t1) * t;
+
+        const A1 = lerp2(p0, p1, (u - t0) / (t1 - t0));
+        const A2 = lerp2(p1, p2, (u - t1) / (t2 - t1));
+        const A3 = lerp2(p2, p3, (u - t2) / (t3 - t2));
+
+        const B1 = lerp2(A1, A2, (u - t0) / (t2 - t0));
+        const B2 = lerp2(A2, A3, (u - t1) / (t3 - t1));
+
+        const C = lerp2(B1, B2, (u - t1) / (t2 - t1));
+        return C;
+    }
+
+    const src = (points || []).filter(p =>
+        p && Number.isFinite(p.x) && Number.isFinite(p.y)
+    );
+    if (src.length < 2) return src;
+
+    const n = src.length;
+
+    const get = (i) => {
+        if (closed) {
+            const k = (i % n + n) % n;
+            return src[k];
+        }
+        if (i < 0) return src[0];
+        if (i >= n) return src[n - 1];
+        return src[i];
+    };
+
+    const out = [];
+    const pushPoint = (p) => {
+        if (out.length >= maxOutputPoints) return false;
+        const prev = out[out.length - 1];
+        if (!prev || prev.x !== p.x || prev.y !== p.y) out.push(p);
+        return true;
+    };
+
+    pushPoint({ x: src[0].x, y: src[0].y });
+
+    const segCount = closed ? n : (n - 1);
+    for (let i = 0; i < segCount; i++) {
+        const p0 = get(i - 1);
+        const p1 = get(i);
+        const p2 = get(i + 1);
+        const p3 = get(i + 2);
+
+        const segLen = dist(p1, p2);
+        const adaptive = Math.round(samplesPerSeg * Math.max(1, segLen * 0.75));
+        const steps = Math.max(minSamplesPerSeg, Math.min(maxSamplesPerSeg, adaptive));
+
+        for (let s = 1; s <= steps; s++) {
+            const t = s / steps;
+            const p = evalSegment(p0, p1, p2, p3, t);
+            if (!pushPoint(p)) return out;
+        }
+    }
+
+    return out;
+}

inventory/static/js/components/grid/widget-core.js

@@ -0,0 +1,459 @@
+import { catmullRomResample } from './spline.js';
+
+export const DEFAULT_DOC = { version: 1, cellSize: 25, shapes: [] };
+export const SHAPE_DEFAULTS = {
+    strokeWidth: 0.12,
+    strokeOpacity: 1,
+    fillOpacity: 1
+};
+
+export function createWidgetCore(env) {
+    let {
+        root, mode, storageKey,
+        gridEl, canvasEl,
+        viewerOffset = { x: 0, y: 0 },
+    } = env;
+
+    let doc = env.doc || structuredClone(DEFAULT_DOC);
+    let cellSize = Number(env.cellSize) || 25;
+    let shapes = Array.isArray(env.shapes) ? env.shapes : [];
+    let selectedShape = env.selectedShape || null;
+
+    let ctx = null;
+    let dpr = 1;
+
+    function clamp01(n, fallback = 1) {
+        const x = Number(n);
+        return Number.isFinite(x) ? Math.min(1, Math.max(0, x)) : fallback;
+    }
+
+    function isFiniteNum(n) { return Number.isFinite(Number(n)); }
+
+    // Document and shape lifecycle
+
+    function loadDoc() {
+        try { return JSON.parse(localStorage.getItem(storageKey)) || structuredClone(DEFAULT_DOC); }
+        catch { return structuredClone(DEFAULT_DOC); }
+    }
+
+    function saveDoc(nextDoc = doc) {
+        const safeDoc = {
+            ...nextDoc,
+            shapes: stripCaches(Array.isArray(nextDoc.shapes) ? nextDoc.shapes : [])
+        };
+        doc = safeDoc;
+        try { localStorage.setItem(storageKey, JSON.stringify(safeDoc)); } catch { }
+    }
+
+    function setDoc(nextDoc) {
+        const d = nextDoc && typeof nextDoc === 'object' ? nextDoc : DEFAULT_DOC;
+        cellSize = Number(d.cellSize) || 25;
+        shapes = rebuildPathCaches(
+            sanitizeShapes(Array.isArray(d.shapes) ? d.shapes : [])
+        );
+        doc = { version: Number(d.version) || 1, cellSize, shapes };
+
+        if (mode === 'editor') {
+            saveDoc(doc);
+        }
+
+        requestAnimationFrame(() => resizeAndSetupCanvas());
+    }
+
+    function sanitizeShapes(list) {
+        const allowed = new Set(['rect', 'ellipse', 'line', 'path']);
+
+        const normStroke = (v, fallback = 0.12) => {
+            const n = Number(v);
+            if (!Number.isFinite(n)) return fallback;
+            return Math.max(0, n);
+        };
+
+        return list.flatMap((s) => {
+            if (!s || typeof s !== 'object' || !allowed.has(s.type)) return [];
+
+            const color = typeof s.color === 'string' ? s.color : '#000000';
+            const fillOpacity = clamp01(s.fillOpacity, SHAPE_DEFAULTS.fillOpacity);
+            const strokeOpacity = clamp01(s.strokeOpacity, SHAPE_DEFAULTS.strokeOpacity);
+
+            if (s.type === 'line') {
+                if (!['x1', 'y1', 'x2', 'y2'].every(k => isFiniteNum(s[k]))) return [];
+                return [{
+                    type: 'line',
+                    x1: +s.x1, y1: +s.y1, x2: +s.x2, y2: +s.y2,
+                    color,
+                    strokeWidth: normStroke(s.strokeWidth, SHAPE_DEFAULTS.strokeWidth),
+                    strokeOpacity
+                }];
+            }
+
+            if (s.type === 'path') {
+                if (!Array.isArray(s.points) || s.points.length < 2) return [];
+
+                const points = s.points.flatMap(p => {
+                    if (!p || !isFiniteNum(p.x) || !isFiniteNum(p.y)) return [];
+                    return [{ x: +p.x, y: +p.y }];
+                });
+                if (points.length < 2) return [];
+
+                return [{
+                    type: 'path',
+                    points,
+                    color,
+                    strokeWidth: normStroke(s.strokeWidth, SHAPE_DEFAULTS.strokeWidth),
+                    strokeOpacity
+                }];
+            }
+
+            if (!['x', 'y', 'w', 'h'].every(k => isFiniteNum(s[k]))) return [];
+            return [{
+                type: s.type,
+                x: +s.x, y: +s.y, w: +s.w, h: +s.h,
+                color,
+                fill: !!s.fill,
+                fillOpacity,
+                strokeOpacity,
+                strokeWidth: normStroke(s.strokeWidth, SHAPE_DEFAULTS.strokeWidth)
+            }];
+        });
+    }
+
+    function stripCaches(shapes) {
+        return shapes.map(s => {
+            if (s.type === 'path') {
+                return {
+                    type: 'path',
+                    points: s.points,
+                    color: s.color,
+                    strokeWidth: s.strokeWidth,
+                    strokeOpacity: s.strokeOpacity
+                };
+            }
+            if (s.type === 'line') {
+                return {
+                    type: 'line',
+                    x1: s.x1, y1: s.y1, x2: s.x2, y2: s.y2,
+                    color: s.color,
+                    strokeWidth: s.strokeWidth,
+                    strokeOpacity: s.strokeOpacity
+                };
+            }
+            if (s.type === 'rect' || s.type === 'ellipse') {
+                return {
+                    type: s.type,
+                    x: s.x, y: s.y, w: s.w, h: s.h,
+                    color: s.color,
+                    fill: !!s.fill,
+                    fillOpacity: s.fillOpacity,
+                    strokeOpacity: s.strokeOpacity,
+                    strokeWidth: s.strokeWidth
+                };
+            }
+            return s; // shouldn't happen
+        });
+    }
+
+    function rebuildPathCaches(list) {
+        const MIN_PTS_FOR_SMOOTH = 4;
+        const MIN_LEN = 2;
+        const MIN_TURN = 0.15;
+
+        return list.map(s => {
+            if (s.type !== 'path') return s;
+
+            const pts = s.points;
+            if (!Array.isArray(s.points) || pts.length < 2) return s;
+            if (!pts.every(p => p && Number.isFinite(p.x) && Number.isFinite(p.y))) return s;
+
+            if (pathLength(pts) < MIN_LEN) return s;
+
+            if (pts.length < MIN_PTS_FOR_SMOOTH) return s;
+
+            if (MIN_TURN != null && totalTurning(pts) < MIN_TURN) return s;
+
+            const renderPoints = catmullRomResample(s.points, {
+                alpha: 0.5,
+                samplesPerSeg: 10,
+                maxSamplesPerSeg: 40,
+                minSamplesPerSeg: 6,
+                closed: false,
+                maxOutputPoints: 4000
+            });
+
+            return {
+                ...s,
+                ...(renderPoints?.length >= 2 ? { renderPoints } : {})
+            };
+        });
+    }
+
+    function totalTurning(points) {
+        let sum = 0;
+
+        for (let i = 1; i < points.length - 1; i++) {
+            const p0 = points[i - 1];
+            const p1 = points[i];
+            const p2 = points[i + 1];
+
+            const v1x = p1.x - p0.x;
+            const v1y = p1.y - p0.y;
+            const v2x = p2.x - p1.x;
+            const v2y = p2.y - p1.y;
+
+            const len1 = Math.hypot(v1x, v1y);
+            const len2 = Math.hypot(v2x, v2y);
+
+            if (len1 === 0 || len2 === 0) continue;
+
+            const cross = Math.abs(v1x * v2y - v1y * v2x);
+
+            sum += cross / (len1 * len2);
+        }
+
+        return sum;
+    }
+
+    function pathLength(pts) {
+        let L = 0;
+        for (let i = 1; i < pts.length; i++) {
+            const dx = pts[i].x - pts[i - 1].x;
+            const dy = pts[i].y - pts[i - 1].y;
+            L += Math.hypot(dx, dy);
+        }
+        return L;
+    }
+
+    function getShapesBounds(shapes) {
+        let minX = Infinity, minY = Infinity, maxX = -Infinity, maxY = -Infinity;
+
+        const expand = (x1, y1, x2, y2) => {
+            minX = Math.min(minX, x1);
+            minY = Math.min(minY, y1);
+            maxX = Math.max(maxX, x2);
+            maxY = Math.max(maxY, y2);
+        };
+
+        for (const s of shapes || []) {
+            if (!s) continue;
+
+            if (s.type === 'rect' || s.type === 'ellipse') {
+                expand(s.x, s.y, s.x + s.w, s.y + s.h);
+            } else if (s.type === 'line') {
+                expand(
+                    Math.min(s.x1, s.x2), Math.min(s.y1, s.y2),
+                    Math.max(s.x1, s.x2), Math.max(s.y1, s.y2)
+                );
+            } else if (s.type === 'path') {
+                const pts = (s.renderPoints?.length >= 2) ? s.renderPoints : s.points;
+                if (!pts?.length) continue;
+                for (const p of pts) expand(p.x, p.y, p.x, p.y);
+            }
+        }
+
+        if (!Number.isFinite(minX)) return null;
+        return { minX, minY, maxX, maxY };
+    }
+
+    // Canvas pipeline
+
+    function resizeAndSetupCanvas() {
+        dpr = window.devicePixelRatio || 1;
+
+        const w = gridEl.clientWidth;
+        const h = gridEl.clientHeight;
+
+        canvasEl.width = Math.round(w * dpr);
+        canvasEl.height = Math.round(h * dpr);
+
+        canvasEl.style.width = `${w}px`;
+        canvasEl.style.height = `${h}px`;
+
+        ctx = canvasEl.getContext('2d');
+        ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
+
+        redrawAll();
+    }
+
+    function clearCanvas() {
+        if (!ctx) return;
+        ctx.clearRect(0, 0, canvasEl.width / dpr, canvasEl.height / dpr);
+    }
+
+    function drawShape(shape) {
+        if (!ctx) return;
+        const toPx = (v) => v * cellSize;
+
+        ctx.save();
+        ctx.strokeStyle = shape.color || '#000000';
+        ctx.lineWidth = Math.max(1, toPx(shape.strokeWidth ?? SHAPE_DEFAULTS.strokeWidth));
+
+        if (shape.type === 'rect' || shape.type === 'ellipse') {
+            const x = toPx(shape.x);
+            const y = toPx(shape.y);
+            const w = toPx(shape.w);
+            const h = toPx(shape.h);
+
+            ctx.globalAlpha = clamp01(shape.strokeOpacity, SHAPE_DEFAULTS.strokeOpacity);
+            if (shape.type === 'rect') {
+                ctx.strokeRect(x, y, w, h);
+            } else {
+                const cx = x + w / 2;
+                const cy = y + h / 2;
+                ctx.beginPath();
+                ctx.ellipse(cx, cy, Math.abs(w / 2), Math.abs(h / 2), 0, 0, Math.PI * 2);
+                ctx.stroke();
+            }
+            ctx.globalAlpha = 1;
+
+            if (shape.fill) {
+                ctx.globalAlpha = clamp01(shape.fillOpacity, SHAPE_DEFAULTS.fillOpacity);
+                ctx.fillStyle = shape.color;
+                if (shape.type === 'rect') {
+                    ctx.fillRect(x, y, w, h);
+                } else {
+                    const cx = x + w / 2;
+                    const cy = y + h / 2;
+                    ctx.beginPath();
+                    ctx.ellipse(cx, cy, Math.abs(w / 2), Math.abs(h / 2), 0, 0, Math.PI * 2);
+                    ctx.fill()
+                }
+                ctx.globalAlpha = 1;
+            }
+
+        } else if (shape.type === 'line') {
+            const x1 = toPx(shape.x1);
+            const y1 = toPx(shape.y1);
+            const x2 = toPx(shape.x2);
+            const y2 = toPx(shape.y2);
+
+            ctx.globalAlpha = clamp01(shape.strokeOpacity, SHAPE_DEFAULTS.strokeOpacity);
+            ctx.lineJoin = 'round';
+            ctx.lineCap = 'round';
+            ctx.beginPath();
+            ctx.moveTo(x1, y1);
+            ctx.lineTo(x2, y2);
+            ctx.stroke();
+            ctx.globalAlpha = 1;
+        } else if (shape.type === 'path') {
+            ctx.globalAlpha = clamp01(shape.strokeOpacity, SHAPE_DEFAULTS.strokeOpacity);
+
+            ctx.lineWidth = Math.max(1, toPx(shape.strokeWidth ?? SHAPE_DEFAULTS.strokeWidth));
+            ctx.lineJoin = 'round';
+            ctx.lineCap = 'round';
+
+            const pts = (shape.renderPoints && shape.renderPoints.length >= 2)
+                ? shape.renderPoints
+                : shape.points;
+            ctx.beginPath();
+            ctx.moveTo(toPx(pts[0].x), toPx(pts[0].y));
+            for (let i = 1; i < pts.length; i++) {
+                ctx.lineTo(toPx(pts[i].x), toPx(pts[i].y));
+            }
+            ctx.stroke();
+        }
+
+        ctx.restore();
+    }
+
+    function redrawAll() {
+        if (!ctx || !shapes) return;
+
+        clearCanvas();
+
+        ctx.save();
+        if (mode !== 'editor') {
+            ctx.translate(viewerOffset.x, viewerOffset.y);
+        }
+        shapes.forEach(drawShape);
+
+        if (mode === 'editor' && selectedShape) {
+            ctx.save();
+            ctx.globalAlpha = 1;
+            ctx.setLineDash([6, 4]);
+            drawShape({
+                ...selectedShape,
+                fill: false,
+                strokeWidth: Math.max(selectedShape.strokeWidth ?? 0.12, 0.12) + (2 / cellSize),
+                strokeOpacity: 1
+            });
+            ctx.restore();
+        }
+
+        ctx.restore();
+    }
+
+    function renderAllWithPreview(previewShape = null, dashed = true) {
+        if (!ctx) return;
+        clearCanvas();
+        shapes.forEach(drawShape);
+
+        if (!previewShape) return;
+
+        ctx.save();
+        if (dashed) ctx.setLineDash([5, 3]);
+        drawShape(previewShape);
+        ctx.restore();
+    }
+
+    // Coordinate conversion
+
+    function pxToGrid(v) {
+        return v / cellSize;
+    }
+
+    function pxToDocPoint(clientX, clientY) {
+        const rect = gridEl.getBoundingClientRect();
+        const x = Math.min(Math.max(clientX, rect.left), rect.right) - rect.left;
+        const y = Math.min(Math.max(clientY, rect.top), rect.bottom) - rect.top;
+        return { x: pxToGrid(x), y: pxToGrid(y) };
+    }
+
+    // Tool state helpers
+
+    function getActiveTool() {
+        const checked = root.querySelector('input[data-tool]:checked');
+        return checked ? checked.value : 'pen';
+    }
+
+    function setActiveTool(toolValue) {
+        const el = root.querySelector(`input[data-tool][value="${CSS.escape(toolValue)}"]`);
+        if (el) el.checked = true;
+    }
+
+    function getActiveType() {
+        const checked = root.querySelector('input[data-gridtype]:checked');
+        return checked ? checked.value : 'noGrid';
+    }
+
+    function setActiveType(typeValue) {
+        const el = root.querySelector(`input[data-gridtype][value="${CSS.escape(typeValue)}"]`);
+        if (el) el.checked = true;
+    }
+
+    return {
+        DEFAULT_DOC,
+        SHAPE_DEFAULTS,
+
+        get doc() { return doc; },
+        get cellSize() { return cellSize; },
+        get shapes() { return shapes; },
+        get ctx() { return ctx; },
+        get selectedShape() { return selectedShape; },
+        set selectedShape(v) { selectedShape = v; },
+        set viewerOffset(v) { viewerOffset = v; },
+
+        loadDoc, saveDoc, setDoc,
+        sanitizeShapes, stripCaches, rebuildPathCaches,
+        getShapesBounds,
+
+        resizeAndSetupCanvas,
+        redrawAll,
+        renderAllWithPreview,
+        pxToDocPoint,
+
+        getActiveTool, setActiveTool,
+        getActiveType, setActiveType,
+
+        clamp01, pxToGrid, isFiniteNum,
+    };
+}

inventory/static/js/components/grid/widget-editor.js

@@ -0,0 +1,831 @@
+import { encode, decode } from './encode-decode.js';
+import { dist2, pickShapeAt } from './geometry.js';
+import { simplifyRDP } from './simplify.js';
+import { SHAPE_DEFAULTS } from './widget-core.js';
+
+export function initWidgetEditor(core, env) {
+    const { root, gridEl, gridWrapEl, toastMessage, storageKey } = env;
+
+    const MAX_HISTORY = 100;
+
+    const clearEl = root.querySelector('[data-clear]');
+    const colorEl = root.querySelector('[data-color]');
+    const coordsEl = root.querySelector('[data-coords]');
+    const dotEl = root.querySelector('[data-dot]');
+    const dotSVGEl = root.querySelector('[data-dot-svg]');
+    const exportEl = root.querySelector('[data-export]');
+    const importButtonEl = root.querySelector('[data-import-button]');
+    const importEl = root.querySelector('[data-import]');
+    const cellSizeEl = root.querySelector('[data-cell-size]');
+    const toolBarEl = root.querySelector('[data-toolbar]');
+    const fillOpacityEl = root.querySelector('[data-fill-opacity]');
+    const strokeOpacityEl = root.querySelector('[data-stroke-opacity]');
+    const strokeWidthEl = root.querySelector('[data-stroke-width]');
+    const cellSizeValEl = root.querySelector('[data-cell-size-val]');
+    const fillValEl = root.querySelector('[data-fill-opacity-val]');
+    const strokeValEl = root.querySelector('[data-stroke-opacity-val]');
+    const widthValEl = root.querySelector('[data-stroke-width-val]');
+
+    function bindRangeWithLabel(inputEl, labelEl, format = (v) => v) {
+        const sync = () => { labelEl.textContent = format(inputEl.value); };
+        inputEl.addEventListener('input', sync);
+        inputEl.addEventListener('change', sync);
+        sync();
+    }
+
+    if (cellSizeEl && cellSizeValEl) bindRangeWithLabel(cellSizeEl, cellSizeValEl, v => `${v}px`);
+    if (fillOpacityEl && fillValEl) bindRangeWithLabel(fillOpacityEl, fillValEl, v => `${parseInt(Number(v) * 100)}%`);
+    if (strokeOpacityEl && strokeValEl) bindRangeWithLabel(strokeOpacityEl, strokeValEl, v => `${parseInt(Number(v) * 100)}%`);
+    if (strokeWidthEl && widthValEl) bindRangeWithLabel(strokeWidthEl, widthValEl, v => `${Math.round(Number(v) * Number(cellSizeEl.value || 0))}px`);
+
+    core.saveDoc({ ...core.doc, shapes: core.shapes });
+
+    const savedTool = localStorage.getItem(`${storageKey}:tool`);
+    if (savedTool) core.setActiveTool(savedTool);
+
+    const savedType = localStorage.getItem(`${storageKey}:gridType`);
+    if (savedType) core.setActiveType(savedType);
+
+    cellSizeEl.value = core.cellSize;
+    let dotSize = Math.floor(Math.max(core.cellSize * 1.25, 32));
+
+    let selectedColor;
+    let currentFillOpacity = core.clamp01(fillOpacityEl?.value ?? 1, 1);
+    let currentStrokeOpacity = core.clamp01(strokeOpacityEl?.value ?? 1, 1);
+    let currentStrokeWidth = Number(strokeWidthEl?.value ?? 0.12) || 0.12;
+    let selectedIndex = -1;
+
+    selectedColor = colorEl?.value || '#000000';
+    if (dotSVGEl) {
+        const circle = dotSVGEl.querySelector('circle');
+        circle?.setAttribute('fill', selectedColor);
+    }
+
+    let currentShape = null;
+    let suppressNextClick = false;
+
+    const history = [structuredClone(core.shapes)];
+    let historyIndex = 0
+
+    let sizingRAF = 0;
+    let lastApplied = { w: 0, h: 0 };
+
+    const ro = new ResizeObserver(scheduleSnappedCellSize);
+    ro.observe(gridWrapEl);
+
+    setGrid();
+    scheduleSnappedCellSize();
+
+    let activePointerId = null;
+
+    if (toolBarEl && window.bootstrap?.Dropdown) {
+        toolBarEl.querySelectorAll('[data-bs-toggle="dropdown"]').forEach((toggle) => {
+            window.bootstrap.Dropdown.getOrCreateInstance(toggle, {
+                popperConfig(defaultConfig) {
+                    return {
+                        ...defaultConfig,
+                        strategy: 'fixed',
+                        modifiers: [
+                            ...(defaultConfig.modifiers || []),
+                            { name: 'preventOverflow', options: { boundary: 'viewport' } },
+                            { name: 'flip', options: { boundary: 'viewport', padding: 8 } },
+                        ],
+                    };
+                },
+            });
+        });
+    }
+
+
+    requestAnimationFrame(() => requestAnimationFrame(scheduleSnappedCellSize));
+
+    const api = {
+        handleKeyDown(e) {
+            const key = e.key.toLowerCase();
+            const t = e.target;
+
+            const isTextField = t && root.contains(t) && (t.matches('input, textarea, select') || t.isContentEditable);
+
+            if (isTextField) {
+                const isUndo = (e.ctrlKey || e.metaKey) && key === 'z';
+                const isRedo = (e.ctrlKey || e.metaKey) && (key === 'y' || (key === 'z' && e.shiftKey));
+
+                if (!isUndo && !isRedo) return;
+            }
+
+            if ((e.ctrlKey || e.metaKey) && key === 'z') {
+                e.preventDefault();
+                if (e.shiftKey) redo();
+                else undo();
+                return;
+            }
+
+            if ((e.ctrlKey || e.metaKey) && key === 'y') {
+                e.preventDefault();
+                redo();
+                return;
+            }
+
+            if (key === 'escape' && currentShape) {
+                e.preventDefault();
+                currentShape = null;
+                core.redrawAll();
+            }
+        },
+
+        handleGlobalPointerUp(e) {
+            finishPointer(e);
+        },
+
+        cancelStroke() { cancelStroke(); }
+    };
+
+    function destroy() {
+        if (window.activeGridWidget === api) window.activeGridWidget = null;
+
+        currentShape = null;
+        activePointerId = null;
+
+        try {
+            if (window.__gridPointerId != null && gridEl.hasPointerCapture?.(window.__gridPointerId)) {
+                gridEl.releasePointerCapture(window.__gridPointerId);
+            }
+        } catch { }
+
+        if (window.__gridPointerOwner === api) {
+            window.__gridPointerOwner = null;
+            window.__gridPointerId = null;
+        }
+
+        ro.disconnect();
+    }
+
+
+    api.destroy = destroy;
+
+    root.addEventListener('focusin', () => { window.activeGridWidget = api; });
+
+    root.addEventListener('pointerdown', () => {
+        window.activeGridWidget = api;
+    }, { capture: true });
+
+    function setGrid() {
+        const type = core.getActiveType();
+
+        gridEl.style.backgroundImage = "";
+        gridEl.style.backgroundSize = "";
+        gridEl.style.backgroundPosition = "";
+        gridEl.style.boxShadow = "none";
+        dotEl.classList.add('d-none');
+
+        // Minor dots
+        const dotPx = Math.max(1, Math.round(core.cellSize * 0.08));
+        const minorColor = '#ddd';
+
+        // Major dots (every 5 cells)
+        const majorStep = core.cellSize * 5;
+        const majorDotPx = Math.max(dotPx + 1, Math.round(core.cellSize * 0.12));
+        const majorColor = '#c4c4c4';
+
+        const minorLayer = `radial-gradient(circle, ${minorColor} ${dotPx}px, transparent ${dotPx}px)`;
+        const majorLayer = `radial-gradient(circle, ${majorColor} ${majorDotPx}px, transparent ${majorDotPx}px)`;
+
+        if (type === 'fullGrid') {
+            gridEl.style.backgroundImage = `${majorLayer}, ${minorLayer}`;
+            gridEl.style.backgroundSize = `${majorStep}px ${majorStep}px, ${core.cellSize}px ${core.cellSize}px`;
+            gridEl.style.backgroundPosition =
+                `${majorStep / 2}px ${majorStep / 2}px, ${core.cellSize / 2}px ${core.cellSize / 2}px`;
+            gridEl.style.boxShadow = "inset 0 0 0 1px #ccc";
+
+        } else if (type === 'verticalGrid') {
+            gridEl.style.backgroundImage = `${majorLayer}, ${minorLayer}`;
+            gridEl.style.backgroundSize = `${majorStep}px 100%, ${core.cellSize}px 100%`;
+            gridEl.style.backgroundPosition =
+                `${majorStep / 2}px 0px, ${core.cellSize / 2}px 0px`;
+            gridEl.style.boxShadow = "inset 0 1px 0 0 #ccc, inset 0 -1px 0 0 #ccc";
+
+        } else if (type === 'horizontalGrid') {
+            gridEl.style.backgroundImage = `${majorLayer}, ${minorLayer}`;
+            gridEl.style.backgroundSize = `100% ${majorStep}px, 100% ${core.cellSize}px`;
+            gridEl.style.backgroundPosition =
+                `0px ${majorStep / 2}px, 0px ${core.cellSize / 2}px`;
+            gridEl.style.boxShadow = "inset 1px 0 0 0 #ccc, inset -1px 0 0 0 #ccc";
+
+        } else { // noGrid
+            gridEl.style.boxShadow = "inset 0 0 0 1px #ccc";
+        }
+    }
+
+    function isInsideRect(clientX, clientY, rect) {
+        return clientX >= rect.left && clientX <= rect.right &&
+            clientY >= rect.top && clientY <= rect.bottom;
+    }
+
+    function finishPointer(e) {
+        if (window.__gridPointerOwner !== api) return;
+        if (!currentShape) return;
+        if (e.pointerId !== activePointerId) return;
+
+        onPointerUp(e);
+        activePointerId = null;
+
+        window.__gridPointerOwner = null;
+        window.__gridPointerId = null;
+    }
+
+
+
+    function penAddPoint(shape, clientX, clientY, minStep = 0.02, maxDtMs = 16) {
+        const p = core.pxToDocPoint(clientX, clientY);
+
+        if (!Array.isArray(shape.points)) shape.points = [];
+        if (shape._lastAddTime == null) shape._lastAddTime = performance.now();
+
+        const pts = shape.points;
+        const last = pts[pts.length - 1];
+
+        const now = performance.now();
+        const dt = now - shape._lastAddTime;
+
+        if (!last) {
+            pts.push(p);
+            shape._lastAddTime = now;
+            return;
+        }
+
+        const dx = p.x - last.x;
+        const dy = p.y - last.y;
+        const d2 = dx * dx + dy * dy;
+
+        if (d2 >= minStep * minStep || dt >= maxDtMs) {
+            pts.push(p);
+            shape._lastAddTime = now;
+        }
+    }
+
+    function undo() {
+        if (historyIndex <= 0) return;
+        historyIndex--;
+        const nextShapes = core.rebuildPathCaches(structuredClone(history[historyIndex]));
+        core.setDoc({ ...core.doc, cellSize: core.cellSize, shapes: nextShapes });
+        core.redrawAll();
+    }
+
+    function redo() {
+        if (historyIndex >= history.length - 1) return;
+        historyIndex++;
+        const nextShapes = core.rebuildPathCaches(structuredClone(history[historyIndex]));
+        core.setDoc({ ...core.doc, cellSize: core.cellSize, shapes: nextShapes });
+        core.redrawAll();
+    }
+
+    function commit(nextShapes) {
+        history.splice(historyIndex + 1);
+
+        history.push(structuredClone(nextShapes));
+        historyIndex++;
+
+        if (history.length > MAX_HISTORY) {
+            const overflow = history.length - MAX_HISTORY;
+            history.splice(0, overflow);
+            historyIndex -= overflow;
+            if (historyIndex < 0) historyIndex = 0;
+        }
+
+        const rebuilt = core.rebuildPathCaches(nextShapes);
+
+        core.setDoc({ ...core.doc, shapes: rebuilt, cellSize: core.cellSize });
+        core.redrawAll();
+    }
+
+    function snapDown(n, step) {
+        return Math.floor(n / step) * step;
+    }
+
+    function applySnappedCellSize() {
+        sizingRAF = 0;
+
+        const grid = core.cellSize;
+        if (!Number.isFinite(grid) || grid < 1) return;
+
+        const w = gridWrapEl.clientWidth;
+        const h = gridWrapEl.clientHeight;
+
+        const snappedW = snapDown(w, grid);
+        const snappedH = snapDown(h, grid);
+
+        // Only touch width-related CSS if width changed
+        const wChanged = snappedW !== lastApplied.w;
+        const hChanged = snappedH !== lastApplied.h;
+        if (!wChanged && !hChanged) return;
+
+        lastApplied = { w: snappedW, h: snappedH };
+
+        // critical: don't let observer see our own updates as layout input
+        ro.disconnect();
+
+        gridEl.style.width = `${snappedW}px`;
+        gridEl.style.height = `${snappedH}px`;
+
+        if (wChanged) {
+            root.style.setProperty('--grid-maxw', `${snappedW}px`);
+        }
+
+        ro.observe(gridWrapEl);
+
+        core.resizeAndSetupCanvas();
+    }
+
+
+    function scheduleSnappedCellSize() {
+        if (sizingRAF) return;
+        sizingRAF = requestAnimationFrame(applySnappedCellSize);
+    }
+
+    function applyCellSize(newSize) {
+        const n = Number(newSize);
+        if (!Number.isFinite(n) || n < 1) return;
+
+        core.setDoc({ ...core.doc, cellSize: n, shapes: core.shapes });
+        dotSize = Math.floor(Math.max(core.cellSize * 1.25, 32));
+        dotSVGEl?.setAttribute('width', dotSize);
+        dotSVGEl?.setAttribute('height', dotSize);
+        setGrid();
+        scheduleSnappedCellSize();
+    }
+
+    function snapToGrid(x, y) {
+        const rect = gridEl.getBoundingClientRect();
+        const clampedX = Math.min(Math.max(x, rect.left), rect.right);
+        const clampedY = Math.min(Math.max(y, rect.top), rect.bottom);
+
+        const localX = clampedX - rect.left;
+        const localY = clampedY - rect.top;
+
+        const grid = core.cellSize;
+        const maxIx = Math.floor(rect.width / grid);
+        const maxIy = Math.floor(rect.height / grid);
+
+        const ix = Math.min(Math.max(Math.round(localX / grid), 0), maxIx);
+        const iy = Math.min(Math.max(Math.round(localY / grid), 0), maxIy);
+
+        const type = core.getActiveType();
+
+        let snapX = localX;
+        let snapY = localY;
+
+        if (type === 'fullGrid' || type === 'verticalGrid') {
+            snapX = Math.min(ix * grid, rect.width);
+        }
+
+        if (type === 'fullGrid' || type === 'horizontalGrid') {
+            snapY = Math.min(iy * grid, rect.height);
+        }
+
+        return {
+            ix,
+            iy,
+            x: snapX,
+            y: snapY,
+            localX,
+            localY
+        };
+    }
+
+    function normalizeRect(shape) {
+        const x1 = core.pxToGrid(shape.x1);
+        const y1 = core.pxToGrid(shape.y1);
+        const x2 = core.pxToGrid(shape.x2);
+        const y2 = core.pxToGrid(shape.y2);
+
+        return {
+            type: 'rect',
+            x: Math.min(x1, x2),
+            y: Math.min(y1, y2),
+            w: Math.abs(x2 - x1),
+            h: Math.abs(y2 - y1),
+            color: shape.color,
+            fill: shape.fill,
+            fillOpacity: core.clamp01(shape.fillOpacity, 1),
+            strokeOpacity: core.clamp01(shape.strokeOpacity, 1),
+            strokeWidth: core.isFiniteNum(shape.strokeWidth) ? Math.max(0, +shape.strokeWidth) : 0.12
+        };
+    }
+
+    function normalizeEllipse(shape) {
+        const r = normalizeRect(shape);
+        return { ...r, type: 'ellipse' };
+    }
+
+    function normalizeLine(shape) {
+        return {
+            type: 'line',
+            x1: core.pxToGrid(shape.x1),
+            y1: core.pxToGrid(shape.y1),
+            x2: core.pxToGrid(shape.x2),
+            y2: core.pxToGrid(shape.y2),
+            color: shape.color,
+            strokeWidth: core.isFiniteNum(shape.strokeWidth) ? Math.max(0, +shape.strokeWidth) : 0.12,
+            strokeOpacity: core.clamp01(shape.strokeOpacity)
+        };
+    }
+
+    function cancelStroke(e) {
+        const owns = (window.__gridPointerOwner === api) &&
+            (e ? window.__gridPointerId === e.pointerId : true);
+
+        if (!owns) return;
+
+        currentShape = null;
+        activePointerId = null;
+
+        window.__gridPointerOwner = null;
+        window.__gridPointerId = null;
+
+        core.redrawAll();
+    }
+
+    function onPointerUp(e) {
+        if (!currentShape) return;
+
+        // Only finalize if this pointer is the captured one (or we failed to capture, sigh)
+        if (gridEl.hasPointerCapture?.(e.pointerId)) {
+            gridEl.releasePointerCapture(e.pointerId);
+        }
+
+        const { x: snapX, y: snapY } = snapToGrid(e.clientX, e.clientY);
+
+        currentShape.x2 = snapX;
+        currentShape.y2 = snapY;
+
+        let finalShape = null;
+
+        if (currentShape.tool === 'pen') {
+            const pts = currentShape.points;
+
+            if (pts.length >= 2) {
+                const coarse = [pts[0]];
+                const minStepPx = 0.75;
+                const minStep = minStepPx / core.cellSize;
+                for (let i = 1; i < pts.length; i++) {
+                    if (dist2(pts[i], coarse[coarse.length - 1]) >= minStep * minStep) {
+                        coarse.push(pts[i]);
+                    }
+                }
+
+                if (coarse.length >= 2) {
+                    const epsilon = Math.max(0.01, (currentShape.strokeWidth ?? 0.12) * 0.75);
+
+                    const simplified = simplifyRDP(coarse, epsilon);
+
+                    if (simplified.length >= 2) {
+                        finalShape = {
+                            type: 'path',
+                            points: simplified,
+                            color: currentShape.color || '#000000',
+                            strokeWidth: core.isFiniteNum(currentShape.strokeWidth) ? Math.max(0, +currentShape.strokeWidth) : SHAPE_DEFAULTS.strokeWidth,
+                            strokeOpacity: core.clamp01(currentShape.strokeOpacity, SHAPE_DEFAULTS.strokeOpacity)
+                        };
+                    }
+                }
+            }
+        } else if (currentShape.tool === 'line') {
+            const line = normalizeLine(currentShape);
+            if (line.x1 !== line.x2 || line.y1 !== line.y2) finalShape = line;
+
+        } else if (currentShape.tool === 'filled' || currentShape.tool === 'outline') {
+            const rect = normalizeRect(currentShape);
+            if (rect.w > 0 && rect.h > 0) finalShape = rect;
+
+        } else if (currentShape.tool === 'filledEllipse' || currentShape.tool === 'outlineEllipse') {
+            const ellipse = normalizeEllipse(currentShape);
+            if (ellipse.w > 0 && ellipse.h > 0) finalShape = ellipse;
+        }
+
+        if (finalShape) {
+            if (finalShape && ('_lastAddTime' in finalShape)) delete finalShape._lastAddTime;
+            commit([...core.shapes, finalShape]);
+
+
+            suppressNextClick = true;
+            setTimeout(() => { suppressNextClick = false; }, 0);
+        }
+
+        currentShape = null;
+        core.renderAllWithPreview(null);
+    }
+
+    gridEl.addEventListener('pointerup', finishPointer);
+
+    function setSelection(hit) {
+        if (!hit) {
+            selectedIndex = -1;
+            core.selectedShape = null;
+            core.redrawAll();
+            return;
+        }
+        selectedIndex = hit.index;
+        core.selectedShape = hit.shape;
+        core.redrawAll();
+    }
+
+    gridEl.addEventListener('click', (e) => {
+        if (suppressNextClick) {
+            suppressNextClick = false;
+            return;
+        }
+        if (currentShape) return;
+        if (e.target.closest('[data-toolbar]')) return;
+
+        const docPt = core.pxToDocPoint(e.clientX, e.clientY);
+        const hit = pickShapeAt(docPt, core.shapes, core.cellSize, { pxTol: 7 });
+        setSelection(hit);
+
+        if (hit) root.dispatchEvent(new CustomEvent('shape:click', { detail: hit }));
+    });
+
+    gridEl.addEventListener('contextmenu', (e) => {
+        e.preventDefault();
+        if (currentShape) return;
+
+        const docPt = core.pxToDocPoint(e.clientX, e.clientY);
+        const hit = pickShapeAt(docPt, core.shapes, core.cellSize, { pxTol: 7 });
+        setSelection(hit);
+
+        root.dispatchEvent(new CustomEvent('shape:contextmenu', {
+            detail: { hit, clientX: e.clientX, clientY: e.clientY }
+        }));
+    });
+
+    gridEl.addEventListener('dblclick', (e) => {
+        if (currentShape) return;
+        if (e.target.closest('[data-toolbar]')) return;
+
+        const docPt = core.pxToDocPoint(e.clientX, e.clientY);
+        const hit = pickShapeAt(docPt, core.shapes, core.cellSize, { pxTol: 7 });
+        setSelection(hit);
+
+        if (hit) root.dispatchEvent(new CustomEvent('shape:dblclick', { detail: hit }));
+    });
+
+    root.querySelectorAll('input[data-tool]').forEach((input) => {
+        input.addEventListener('change', () => {
+            if (input.checked) {
+                localStorage.setItem(`${storageKey}:tool`, input.value);
+            }
+        });
+    });
+
+    root.querySelectorAll('input[data-gridtype]').forEach((input) => {
+        input.addEventListener('change', () => {
+            if (input.checked) {
+                localStorage.setItem(`${storageKey}:gridType`, input.value);
+            }
+            setGrid();
+            core.redrawAll();
+        });
+    });
+
+
+    cellSizeEl.addEventListener('input', () => applyCellSize(cellSizeEl.value));
+    cellSizeEl.addEventListener('change', () => applyCellSize(cellSizeEl.value));
+
+    importButtonEl.addEventListener('click', () => importEl.click());
+
+    importEl.addEventListener('change', (e) => {
+        const file = e.target.files[0];
+        if (!file) return;
+
+        const reader = new FileReader();
+        reader.onload = () => {
+            try {
+                const data = decode(JSON.parse(reader.result));
+
+                if (Number.isFinite(Number(data.cellSize)) && Number(data.cellSize) >= 1) {
+                    cellSizeEl.value = data.cellSize;
+                    applyCellSize(data.cellSize);
+                }
+
+                const loadedShapes = Array.isArray(data?.shapes) ? data.shapes : [];
+                const rebuilt = core.rebuildPathCaches(core.sanitizeShapes(loadedShapes));
+                core.setDoc({ version: Number(data?.version) || 1, cellSize: Number(data?.cellSize) || core.cellSize, shapes: rebuilt });
+
+                history.length = 0;
+                history.push(structuredClone(core.shapes));
+                historyIndex = 0;
+
+                core.redrawAll();
+            } catch {
+                toastMessage('Failed to load data from JSON file.', 'danger');
+            }
+        };
+        reader.readAsText(file);
+    });
+
+    exportEl.addEventListener('click', () => {
+        const payload = encode({ cellSize: core.cellSize, shapes: core.shapes, stripCaches: core.stripCaches, SHAPE_DEFAULTS });
+        const blob = new Blob([JSON.stringify(payload)], { type: 'application/json' });
+        const url = URL.createObjectURL(blob);
+        const a = document.createElement('a');
+        a.href = url;
+        a.download = 'grid-shapes.json';
+        a.click();
+        URL.revokeObjectURL(url);
+    });
+
+    clearEl.addEventListener('click', () => {
+        cellSizeEl.value = 25;
+        core.setDoc({ ...core.doc, cellSize: 25, shapes: [] });
+
+        history.length = 0;
+        history.push([]);
+        historyIndex = 0;
+
+        core.redrawAll();
+    });
+
+    colorEl.addEventListener('input', () => {
+        selectedColor = colorEl.value || '#000000';
+        const circle = dotSVGEl.querySelector('circle');
+        if (circle) {
+            circle.setAttribute('fill', selectedColor);
+        }
+    });
+
+    fillOpacityEl?.addEventListener('input', () => {
+        currentFillOpacity = core.clamp01(fillOpacityEl.value, 1);
+    });
+
+    fillOpacityEl?.addEventListener('change', () => {
+        currentFillOpacity = core.clamp01(fillOpacityEl.value, 1);
+    });
+
+    strokeOpacityEl?.addEventListener('input', () => {
+        currentStrokeOpacity = core.clamp01(strokeOpacityEl.value, 1);
+    });
+
+    strokeOpacityEl?.addEventListener('change', () => {
+        currentStrokeOpacity = core.clamp01(strokeOpacityEl.value, 1);
+    });
+
+    strokeWidthEl?.addEventListener('input', () => {
+        currentStrokeWidth = Math.max(0, Number(strokeWidthEl.value) || 0.12);
+    });
+
+    strokeWidthEl?.addEventListener('change', () => {
+        currentStrokeWidth = Math.max(0, Number(strokeWidthEl.value) || 0.12);
+    });
+
+    gridEl.addEventListener('pointercancel', (e) => cancelStroke(e));
+    gridEl.addEventListener('lostpointercapture', (e) => cancelStroke(e));
+
+    gridEl.addEventListener('pointermove', (e) => {
+        if (!core.ctx) return;
+
+        const rect = gridEl.getBoundingClientRect();
+        const inside = isInsideRect(e.clientX, e.clientY, rect);
+        const drawing = !!currentShape;
+
+        const { ix, iy, x: snapX, y: snapY, localX, localY } = snapToGrid(e.clientX, e.clientY);
+        const tool = core.getActiveTool();
+
+        if (!drawing && !inside) {
+            coordsEl.classList.add('d-none');
+            dotEl.classList.add('d-none');
+        } else {
+            coordsEl.classList.remove('d-none');
+
+            if (core.getActiveType() !== 'noGrid' && tool !== 'pen') {
+                dotEl.classList.remove('d-none');
+
+                const wrapRect = gridWrapEl.getBoundingClientRect();
+                const offsetX = rect.left - wrapRect.left;
+                const offsetY = rect.top - wrapRect.top;
+
+                dotEl.style.left = `${offsetX + snapX}px`;
+                dotEl.style.top = `${offsetY + snapY}px`;
+            } else {
+                dotEl.classList.add('d-none');
+            }
+        }
+
+        if (core.getActiveType() == 'noGrid') {
+            coordsEl.innerText = `(px x=${Math.round(localX)} y=${Math.round(localY)})`;
+        } else {
+            coordsEl.innerText = `(x=${ix} (${snapX}px) y=${iy} (${snapY}px))`;
+        }
+
+        if (!currentShape) return;
+
+        // PEN: mutate points and preview the same shape object
+        if (currentShape.tool === 'pen') {
+            const minStepPx = 0.75;
+            const minStep = minStepPx / core.cellSize;
+            penAddPoint(currentShape, e.clientX, e.clientY, minStep, 16);
+
+            // realtime instrumentation
+            coordsEl.innerText += ` | pts=${currentShape.points?.length ?? 0}`;
+
+            core.renderAllWithPreview(currentShape, false);
+            return;
+        }
+
+        // Other tools: build a normalized preview shape
+        let preview = null;
+
+        if (currentShape.tool === 'line') {
+            preview = normalizeLine({
+                x1: currentShape.x1,
+                y1: currentShape.y1,
+                x2: snapX,
+                y2: snapY,
+                color: currentShape.color,
+                strokeWidth: currentShape.strokeWidth,
+                strokeOpacity: currentShape.strokeOpacity
+            });
+        } else if (currentShape.tool === 'filled' || currentShape.tool === 'outline') {
+            preview = normalizeRect({ ...currentShape, x2: snapX, y2: snapY });
+        } else if (currentShape.tool === 'filledEllipse' || currentShape.tool === 'outlineEllipse') {
+            preview = normalizeEllipse({ ...currentShape, x2: snapX, y2: snapY });
+        }
+
+        core.renderAllWithPreview(preview, currentShape.tool !== 'pen');
+    });
+
+    gridEl.addEventListener('pointerleave', (e) => {
+        coordsEl.classList.add('d-none');
+        dotEl.classList.add('d-none');
+    });
+
+    gridEl.addEventListener('pointerdown', (e) => {
+        if (e.button !== 0) return;
+
+        if (e.target.closest('[data-toolbar]')) return;
+
+        e.preventDefault();
+        activePointerId = e.pointerId;
+
+        window.__gridPointerOwner = api;
+        window.__gridPointerId = e.pointerId;
+
+        try {
+            gridEl.setPointerCapture(e.pointerId);
+        } catch {
+            // ignore: some browsers / scenarios won't allow capture
+        }
+
+        const { x: snapX, y: snapY } = snapToGrid(e.clientX, e.clientY);
+        const tool = core.getActiveTool();
+
+        if (tool === 'line') {
+            currentShape = {
+                tool,
+                type: 'line',
+                x1: snapX,
+                y1: snapY,
+                x2: snapX,
+                y2: snapY,
+                color: selectedColor,
+                strokeWidth: currentStrokeWidth,
+                strokeOpacity: currentStrokeOpacity
+            };
+        } else if (tool === 'outline' || tool === 'filled') {
+            currentShape = {
+                tool,
+                x1: snapX,
+                y1: snapY,
+                x2: snapX,
+                y2: snapY,
+                color: selectedColor,
+                fill: (tool === 'filled'),
+                fillOpacity: currentFillOpacity,
+                strokeOpacity: currentStrokeOpacity,
+                strokeWidth: currentStrokeWidth
+            };
+        } else if (tool === 'outlineEllipse' || tool === 'filledEllipse') {
+            currentShape = {
+                tool,
+                x1: snapX,
+                y1: snapY,
+                x2: snapX,
+                y2: snapY,
+                color: selectedColor,
+                fill: (tool === 'filledEllipse'),
+                fillOpacity: currentFillOpacity,
+                strokeOpacity: currentStrokeOpacity,
+                strokeWidth: currentStrokeWidth
+            };
+        } else if (tool === 'pen') {
+            const p = core.pxToDocPoint(e.clientX, e.clientY);
+            currentShape = {
+                tool,
+                type: 'path',
+                points: [p],
+                color: selectedColor,
+                strokeWidth: currentStrokeWidth,
+                strokeOpacity: currentStrokeOpacity,
+                _lastAddTime: performance.now()
+            };
+        }
+    });
+}

inventory/static/js/components/grid/widget-init.js

@@ -0,0 +1,56 @@
+import { createWidgetCore, DEFAULT_DOC } from "./widget-core.js";
+import { initWidgetEditor } from "./widget-editor.js";
+
+export function initGridWidget(root, opts = {}) {
+    const mode = opts.mode || 'editor';
+    const storageKey = opts.storageKey ?? 'gridDoc';
+
+    const canvasEl = root.querySelector('[data-canvas]');
+    const gridEl = root.querySelector('[data-grid]');
+    const gridWrapEl = root.querySelector('[data-grid-wrap]');
+
+    if (!canvasEl || !gridEl || !gridWrapEl) {
+        throw new Error("Grid widget: missing required viewer elements.");
+    }
+
+    const toastMessage = opts.toastMessage || (() => { });
+
+    const core = createWidgetCore({
+        root,
+        mode,
+        storageKey,
+        gridEl,
+        canvasEl,
+        viewerOffset: opts.viewerOffset || { x: 0, y: 0 },
+        doc: opts.doc,
+        cellSize: opts.cellSize,
+        shapes: opts.shapes
+    });
+
+    const env = { root, gridEl, gridWrapEl, toastMessage, storageKey };
+
+    let editorApi = null;
+    if (mode === 'editor') {
+        editorApi = initWidgetEditor(core, env);
+    }
+
+    const api = {
+        core,
+        mode,
+
+        redraw() { core.redrawAll(); },
+        destroy() { editorApi?.destroy?.(); },
+
+        get doc() { return core.doc; },
+        get shapes() { return core.shapes; },
+        get cellSize() { return core.cellSize; },
+    };
+
+    if(editorApi) {
+        api.handleKeyDown = editorApi.handleKeyDown;
+        api.handleGlobalPointerUp = editorApi.handleGlobalPointerUp;
+        api.cancelStroke = editorApi.cancelStroke;
+    }
+
+    return api;
+}

inventory/static/js/components/grid/widget-viewer.js

@@ -0,0 +1,66 @@
+import { decode } from "./encode-decode.js";
+
+export function initWidgetViewer(core, env) {
+    const { mode, gridEl, gridWrapEl } = env;
+
+    if (mode === 'editor') return null;
+
+    let resizeRAF = 0;
+
+    function applyViewerBoundsSizing() {
+        const b = core.getShapesBounds(core.shapes);
+        const padCells = 0.5;
+
+        const wCells = b ? (b.maxX - b.minX + padCells * 2) : 10;
+        const hCells = b ? (b.maxY - b.minY + padCells * 2) : 10;
+
+        const wPx = Math.max(1, Math.ceil(wCells * core.cellSize));
+        const hPx = Math.max(1, Math.ceil(hCells * core.cellSize));
+
+        gridEl.style.width = `${wPx}px`;
+        gridEl.style.height = `${hPx}px`;
+        gridWrapEl.style.width = `${wPx}px`;
+        gridWrapEl.style.height = `${hPx}px`;
+
+        if (b) {
+            core.viewerOffset = {
+                x: (-b.minX + padCells) * core.cellSize,
+                y: (-b.minY + padCells) * core.cellSize
+            };
+        } else {
+            core.viewerOffset = { x: 0, y: 0 };
+        }
+    }
+
+    const scheduleResize = () => {
+        if (resizeRAF) return;
+        resizeRAF = requestAnimationFrame(() => {
+            resizeRAF = 0;
+            applyViewerBoundsSizing();
+            core.resizeAndSetupCanvas();
+        });
+    };
+
+    const ro = new ResizeObserver(scheduleResize);
+    ro.observe(gridWrapEl);
+
+    window.addEventListener('resize', scheduleResize, { passive: true });
+
+    requestAnimationFrame(scheduleResize);
+
+    function setDoc(nextDoc) {
+        core.setDoc(nextDoc);
+        applyViewerBoundsSizing();
+        core.resizeAndSetupCanvas();
+    }
+
+    return {
+        setDoc,
+        redraw: () => core.redrawAll(),
+        destroy() {
+            ro.disconnect();
+            window.removeEventListener('resize', scheduleResize);
+        },
+        decode
+    };
+}

inventory/templates/testing.html

@@ -28,15 +28,15 @@
     <div class="col">
         {{ draw.drawWidget('test6') }}
     </div -->
-    <!-- div class="col" style="height: 80vh;">
+    <div class="col" style="height: 80vh;">
         I am testing a thing.
         {{ draw.viewWidget('test2', jsonImage) }}
         {{ draw.viewWidget('test3', jsonImage2) }}
         The thing has been tested.
-    </div -->
+    </div>
 </div>
 {% endblock %}
 
 {% block scriptincludes %}
-<script src="{{ url_for('static', filename='js/components/draw.js') }}"></script>
+<script type="module" src="{{ url_for('static', filename='js/components/grid/index.js') }}"></script>
 {% endblock %}