import { listFiles } from "@/lib/storage";
import { getSession } from "@/lib/auth/session";
import { canAccessBranch } from "@/lib/auth/permissions";
import {
	withErrorHandling,
	json,
	badRequest,
	unauthorized,
	forbidden,
} from "@/lib/api/errors";
import { mapStorageReadError } from "@/lib/api/storageErrors";

/**
 * Next.js Route Handler caching configuration (RHL-006):
 *
 * We force this route to execute dynamically on every request.
 *
 * Reasons:
 * - NAS contents can change at any time (new scans).
 * - Auth/RBAC-protected responses must not be cached/shared across users.
 * - We rely on a small storage-layer TTL micro-cache instead of Next route caching.
 */
export const dynamic = "force-dynamic";

/**
 * GET /api/files?branch=&year=&month=&day=
 *
 * Happy-path response must remain unchanged:
 * { "branch":"NL01", "year":"2024", "month":"10", "day":"23", "files":[...] }
 */
export const GET = withErrorHandling(
	async function GET(request) {
		const session = await getSession();

		if (!session) {
			throw unauthorized("AUTH_UNAUTHENTICATED", "Unauthorized");
		}

		const { searchParams } = new URL(request.url);

		// Query params are required for this endpoint.
		const branch = searchParams.get("branch");
		const year = searchParams.get("year");
		const month = searchParams.get("month");
		const day = searchParams.get("day");

		const missing = [];
		if (!branch) missing.push("branch");
		if (!year) missing.push("year");
		if (!month) missing.push("month");
		if (!day) missing.push("day");

		if (missing.length > 0) {
			throw badRequest(
				"VALIDATION_MISSING_QUERY",
				"Missing required query parameter(s)",
				{ params: missing }
			);
		}

		if (!canAccessBranch(session, branch)) {
			throw forbidden("AUTH_FORBIDDEN_BRANCH", "Forbidden");
		}

		try {
			const files = await listFiles(branch, year, month, day);
			return json({ branch, year, month, day, files }, 200);
		} catch (err) {
			throw await mapStorageReadError(err, {
				details: { branch, year, month, day },
			});
		}
	},
	{ logPrefix: "[api/files]" }
);