osbtools/src/storyboarding/storyboard.ts

A set of tools for working with osu! storyboards

import { ESbElementProperty, ESbElementType, ESbLayer } from "../types/enums";
import { TSbLayerData, TSbLayersBuilder } from "../types/types";
import { parseElementGroupProperty, parseElementProperty, parseElementTitle } from "../utils/parsers";
import SbEmptyElement from "./sbEmptyElement";
import StoryboardElement from "./storyboardElement";

const layerData = (title: string): TSbLayerData<StoryboardElement> => ({
	title,
	elements: []
});

type TLayers = TSbLayersBuilder<ESbLayer, StoryboardElement>;

class Storyboard {
	readonly #elements: StoryboardElement[] = [];
	readonly #layers: TLayers = {
		[ESbLayer.Background]: layerData("//Storyboard Layer 0 (Background)"),
		[ESbLayer.Fail]: layerData("//Storyboard Layer 1 (Fail)"),
		[ESbLayer.Pass]: layerData("//Storyboard Layer 2 (Pass)"),
		[ESbLayer.Foreground]: layerData("//Storyboard Layer 3 (Foreground)"),
		[ESbLayer.Overlay]: layerData("//Storyboard Layer 4 (Overlay)"),
		[ESbLayer.Sound]: layerData("//Storyboard Sound Samples")
	} as const;

	constructor(osb?: string) {
		if (!osb) return;

		this.parse(osb, false);
	}

	addElement(element: StoryboardElement): Storyboard {
		this.#elements.push(element);
		this.#layers[element.getData().layer].elements.push(element);
		return this;
	}

	parse(osb: string, createNew: boolean = true): Storyboard | undefined {
		const sb = new Storyboard();

		let currentPropertyType: ESbElementProperty | null = null;
		let currentPropertyTrimmedLine: string | null = null;
		let currentGroupElement = new SbEmptyElement();
		let currentElement: StoryboardElement | null = null;

		const lines = osb.split("\n");

		lines.forEach((line, index) => {
			if (line.startsWith("//") || line.startsWith("[")) return;

			const isElementTitle =
				line.startsWith(ESbElementType.Sprite) ||
				line.startsWith(ESbElementType.Animation) ||
				line.startsWith(ESbElementType.Sample);

			if (isElementTitle) {
				currentElement = null;
			}

			const isElementProperty = line.startsWith(" ");
			const isElementPropertyGroup = line.startsWith("  ");

			if (currentElement) {
				const trimmedLine = line.trim();
				const type = trimmedLine.substring(0, trimmedLine[1] !== "," ? 2 : 1) as ESbElementProperty;

				if (isElementProperty && !isElementPropertyGroup) {
					currentPropertyType = type;
					currentPropertyTrimmedLine = trimmedLine;
					parseElementProperty(trimmedLine, type, currentElement);
				} else if (isElementPropertyGroup) {
					const isLastElementPropertyGroup =
						(typeof lines[index + 1] === "string" && !lines[index + 1].startsWith("  ")) || !lines[index + 1];

					parseElementProperty(trimmedLine, type, currentGroupElement);
					if (isLastElementPropertyGroup && currentPropertyType && currentPropertyTrimmedLine) {
						parseElementGroupProperty(
							currentPropertyTrimmedLine,
							currentPropertyType,
							currentElement,
							currentGroupElement
						);
						currentGroupElement = new SbEmptyElement();
					}
				}
			}

			parseElementTitle(line, ESbElementType.Sprite, (element) => {
				currentElement = element;
			});
			parseElementTitle(line, ESbElementType.Animation, (element) => {
				currentElement = element;
			});
			parseElementTitle(line, ESbElementType.Sample, (element) => {
				currentElement = element;
			});

			if (currentElement && isElementTitle) {
				if (!createNew) this.addElement(currentElement);
				else sb.addElement(currentElement);
			}
		});

		if (createNew) return sb;
	}

	getElements(): StoryboardElement[] {
		return this.#elements;
	}

	getElement(index: number): StoryboardElement | null {
		return this.#elements[index] || null;
	}

	getLayers(): TLayers {
		return this.#layers;
	}

	toString(): string {
		return [
			"[Events]",
			"//Background and Video events",
			...Object.entries(this.getLayers()).map(([, layerData]) => {
				const { title, elements } = layerData ?? {};
				return [title, ...elements.map((element) => element.toString())].join("\n");
			})
		].join("\n");
	}
}

export default Storyboard;