import type { ProvisioningIntent } from "../notion-as-code/provisioning.js";

/** Check App-local references without treating code examples as placements. */
export function validateCustomBlockReferences(
	intents: readonly ProvisioningIntent[],
	customBlockKeys: ReadonlySet<string>,
): void {
	for (const intent of intents) {
		if (intent.type !== "page") continue;
		if (intent.customBlockKey !== undefined && !customBlockKeys.has(intent.customBlockKey)) {
			throw new Error(
				`APP.md custom_block "${intent.customBlockKey}" does not match any file in src/customBlocks.`,
			);
		}
		if (!intent.content) continue;
		let fence: { marker: string; length: number } | undefined;
		for (const line of intent.content.split(/\r?\n/)) {
			// Nested list/quote contents use the same block syntax as top-level pages.
			const content = line.replace(/^\s*(?:>\s*)*/, "").replace(/^(?:[-+*]|\d+[.)])\s+/, "");
			const delimiter = content.match(/^(`{3,}|~{3,})(.*)$/);
			const delimiterMarker = delimiter?.[1] ?? "";
			const delimiterTail = delimiter?.[2] ?? "";
			if (fence) {
				if (
					delimiter &&
					delimiterMarker.charAt(0) === fence.marker &&
					delimiterMarker.length >= fence.length &&
					!delimiterTail.trim()
				)
					fence = undefined;
				continue;
			}
			if (delimiter) {
				fence = { marker: delimiterMarker.charAt(0), length: delimiterMarker.length };
				continue;
			}
			const reference = content.match(
				/^<custom-block\s+definition-key\s*=\s*(?:"([^"<>]*)"|'([^'<>]*)')\s*\/>\s*$/,
			);
			if (!reference) continue; // The server parser validates the complete NFM grammar.
			const key = (reference[1] ?? reference[2] ?? "").replace(
				/&(?:amp|quot|apos|lt|gt);/g,
				(entity) =>
					({ "&amp;": "&", "&quot;": '"', "&apos;": "'", "&lt;": "<", "&gt;": ">" })[
						entity
					]!,
			);
			if (!customBlockKeys.has(key)) {
				throw new Error(
					`Page "${intent.resourceId}" references undeclared custom block key "${key}". Declare src/customBlocks/${key}.ts or use definition-id for an existing definition.`,
				);
			}
		}
	}
}