Add a dd-range component for repeated checkboxes that represent something like "1/3"

module/components/range.mjs

@@ -0,0 +1,139 @@
+import { DotDungeonIcon } from "./icon.mjs";
+import { StyledShadowElement } from "./mixins/Styles.mjs";
+
+/**
+Attributes:
+@property {string} name - The path to the value to update in the datamodel
+@property {number} value - The actual value of the input
+@property {number} max - The maximum value that this range has
+
+@extends {HTMLElement}
+*/
+export class DotDungeonRange
+extends StyledShadowElement(
+	HTMLElement,
+	{ mode: `open`, delegatesFocus: true }
+) {
+	static elementName = `dd-range`;
+	static formAssociated = true;
+
+	static observedAttributes = [`max`];
+
+	static _stylePath = `v3/components/range.css`;
+
+	_internals;
+	#input;
+
+	constructor() {
+		super();
+
+		// Form internals
+		this._internals = this.attachInternals();
+		this._internals.role = `spinbutton`;
+	};
+
+	get form() {
+		return this._internals.form;
+	};
+
+	get name() {
+		return this.getAttribute(`name`);
+	};
+	set name(value) {
+		this.setAttribute(`name`, value);
+	};
+
+	get value() {
+		try {
+			return parseInt(this.getAttribute(`value`));
+		} catch {
+			throw new Error(`Failed to parse attribute: "value" - Make sure it's an integer`);
+		};
+	};
+	set value(value) {
+		this.setAttribute(`value`, value);
+	};
+
+	get max() {
+		try {
+			return parseInt(this.getAttribute(`max`));
+		} catch {
+			throw new Error(`Failed to parse attribute: "max" - Make sure it's an integer`);
+		};
+	};
+	set max(value) {
+		this.setAttribute(`max`, value);
+	};
+
+	get type() {
+		return `number`;
+	};
+
+	connectedCallback() {
+		super.connectedCallback();
+
+		// Attribute validation
+		if (!this.hasAttribute(`max`)) {
+			throw new Error(`dotdungeon | Cannot have a range without a maximum value`);
+		};
+
+		// Keyboard accessible input for the thing
+		this.#input = document.createElement(`input`);
+		this.#input.type = `number`;
+		this.#input.min = 0;
+		this.#input.max = this.max;
+		this.#input.value = this.value;
+		this.#input.addEventListener(`change`, () => {
+			const inputValue = parseInt(this.#input.value);
+			if (inputValue === this.value) return;
+			this._updateValue.bind(this)(Math.sign(this.value - inputValue));
+			this._updateValue(Math.sign(this.value - inputValue));
+		});
+		this._shadow.appendChild(this.#input);
+
+		// Shadow-DOM construction
+		this._elements = new Array(this.max);
+		const container = document.createElement(`div`);
+		container.classList.add(`container`);
+
+		// Creating the node for filled content
+		const filledContainer = document.createElement(`div`);
+		filledContainer.classList.add(`range-increment`, `filled`);
+		const filledNode = this.querySelector(`[slot="filled"]`);
+		if (filledNode) filledContainer.appendChild(filledNode);
+
+		const emptyContainer = document.createElement(`div`);
+		emptyContainer.classList.add(`range-increment`, `empty`);
+		const emptyNode = this.querySelector(`[slot="empty"]`);
+		if (emptyNode) emptyContainer.appendChild(emptyNode);
+
+		this._elements.fill(filledContainer, 0, this.value);
+		this._elements.fill(emptyContainer, this.value);
+		container.append(...this._elements.map((slot, i) => {
+			const node = slot.cloneNode(true);
+			node.setAttribute(`data-index`, i + 1);
+			node.addEventListener(`click`, () => {
+				const filled = node.classList.contains(`filled`);
+				this._updateValue(filled ? -1 : 1);
+			});
+			return node;
+		}));
+		this._shadow.appendChild(container);
+
+		/*
+		This converts all of the namespace prefixed properties on the element to
+		CSS variables so that they don't all need to be provided by doing style=""
+		*/
+		for (const attrVar of this.attributes) {
+			if (attrVar.name?.startsWith(`var:`)) {
+				const prop = attrVar.name.replace(`var:`, ``);
+				this.style.setProperty(`--` + prop, attrVar.value);
+			};
+		};
+	};
+
+	_updateValue(delta) {
+		this.value += delta;
+		this.dispatchEvent(new Event(`change`, { bubbles: true }));
+	};
+};