import type { Did } from "@atcute/lexicons/syntax";
import { error } from "@sveltejs/kit";
import type { BobbinContext, XrpcRequestInit } from "$lib/api/client";
import { items } from "$lib/api/pagination";

export type RepoRole = "owner" | "collaborator" | "none";

export interface RepoAccess {
	readonly role: RepoRole;
	readonly canPush: boolean;
	readonly canAdminister: boolean;
}

export const NO_ACCESS: RepoAccess = { role: "none", canPush: false, canAdminister: false };

export const accessFor = (role: RepoRole): RepoAccess => ({
	role,
	canPush: role !== "none",
	canAdminister: role === "owner"
});

export interface RepoIdentity {
	readonly ownerDid: string;
	readonly repoDid?: string;
}

const COLLABORATOR_PAGES = 5;

// pending invites grant nothing, the knot requires an acceptance record
export const resolveRepoAccess = async (
	ctx: BobbinContext,
	repo: RepoIdentity,
	viewerDid: string | undefined,
	init?: XrpcRequestInit
): Promise<RepoAccess> => {
	if (!viewerDid) return NO_ACCESS;
	if (viewerDid === repo.ownerDid) return accessFor("owner");
	if (!repo.repoDid) return NO_ACCESS;
	for await (const collaborator of items(
		ctx,
		"sh.tangled.repo.listCollaborators",
		{ subject: repo.repoDid as Did, limit: 100 },
		{ ...init, maxPages: COLLABORATOR_PAGES }
	)) {
		if (collaborator.subject === viewerDid) return accessFor("collaborator");
	}
	return NO_ACCESS;
};

export const requireRepoAdmin = (access: RepoAccess): void => {
	if (!access.canAdminister) error(403, "Only the repository owner can change this");
};