import { PreparedImage } from "./image-pipeline.ts";

export interface DraftImage {
	placeholder: string;
	prepared: PreparedImage;
}

/** Owns numbering and active draft identity; pending work cannot revive removed entries. */
export class DraftStore {
	images = new Map<string, DraftImage>();
	private nextNumber = 1;

	allocate(text = "", entries: ReadonlyMap<string, DraftImage> = this.images): string {
		let marker: string;
		do { marker = `[Image #${this.nextNumber++}]`; }
		while (text.includes(marker) || entries.has(marker));
		return marker;
	}

	reset(nextNumber?: number): void {
		this.images = new Map();
		if (nextNumber !== undefined) this.nextNumber = nextNumber;
	}

	has(image: DraftImage): boolean {
		return this.images.get(image.placeholder) === image;
	}

	reference(marker: string): string | undefined {
		return this.images.get(marker)?.prepared.reference;
	}
}