export abstract class Builder {
	abstract ownsFile(file_path: string): boolean;
	abstract getName(): string;
	abstract _build(): Promise<void>;
	abstract dispose(): Promise<void>;

	constructor(
		public project_dir: string,
		public style_dirs: string[]
	) {}

	public ongoing_build: Promise<void> | null = null;

	public build(notifier?: (message: string) => void) {
		if (!this.ongoing_build) {
			const build = this._build()
				.catch((err) => {
					console.error(err);
				})
				.then(() => {
					notifier?.(this.getName());
					this.ongoing_build = null;
				});
			this.ongoing_build = build;
		}
		return this.ongoing_build;
	}
}