import z from "zod";
import { Store, type StoreType } from "./entities/Stores";
import type { User } from "./entities/User";
import { getFriends } from "./entities/Follow";

export const locationStore = z
	.object({
		lat: z.number().min(-90).max(90),
		lng: z.number().min(-180).max(180),
		name: z.string().min(1).max(100),
		icon: z.string().min(1).max(100).optional(),
	})
	.strict();

export const vehicleStore = z
	.object({
		name: z.string().min(1).max(100),
		legalMaxSpeed: z.number().min(0).max(300),
		actualMaxSpeed: z.number().min(0).max(300),
		type: z.enum(["car", "truck", "motorcycle", "bicycle", "motor_scooter"]),
		weight: z.number().min(0).max(100000).optional(),
		width: z.number().min(0).max(10).optional(),
		axisLoad: z.number().min(0).max(100000).optional(),
		height: z.number().min(0).max(20).optional(),
		length: z.number().min(0).max(100).optional(),
		emissionClass: z.string().min(1).max(50),
		fuelType: z.enum(["petrol", "diesel", "electric"]),
		preferredFuel: z.string().min(1).max(50),
	})
	.strict();

export const routeStore = z.object({
	name: z.string().min(1).max(100),
	locations: z.array(
		z.object({
			lat: z.number().min(-90).max(90),
			lon: z.number().min(-180).max(180),
		}),
	),
	legs: z.array(
		z.object({
			shape: z.string(),
			maneuvers: z.array(
				z.object({
					type: z.number(),
				}),
			),
		}),
	),
});

export const storeTypes: Record<StoreType, z.ZodSchema> = {
	location: locationStore,
	vehicle: vehicleStore,
	route: routeStore,
};

const sharedStoreTypes: StoreType[] = ["vehicle"];

export const SyncPayload = z.object({
	changes: z.array(
		z.object({
			id: z.uuid(),
			operation: z.enum(["create", "update", "delete"]),
			data: z.string(),
			modified_at: z
				.string()
				.refine((val) => !isNaN(Date.parse(val)), { message: "Invalid date" }),
			type: z.enum(["location", "vehicle", "route"]),
			name: z.string().min(1).max(100),
		}),
	),
	stores: z.array(
		z.object({
			id: z.uuid(),
			modified_at: z
				.string()
				.refine((val) => !isNaN(Date.parse(val)), { message: "Invalid date" }),
		}),
	),
});

export type SyncPayload = z.infer<typeof SyncPayload>;

export function verifyStoreData(type: StoreType, data: string) {
	const schema = storeTypes[type];
	if (!schema) return false;
	if (data === "null") return true; // allow null data
	try {
		const parsedData = JSON.parse(data);
		schema.parse(parsedData);
		return true;
	} catch {
		return false;
	}
}

export async function sync(payload: SyncPayload, user: User) {
	const changes: Store[] = [];
	// Apply changes from client
	for (const change of payload.changes) {
		const store = await Store.findOne({
			where: { id: change.id },
			relations: { user: true },
		});
		if (!verifyStoreData(change.type, change.data)) {
			// Invalid data
			if (store) changes.push(store); // Send back the store to the client to overwrite their changes
			continue;
		}
		if (!store) {
			// Store doesn't exist, create it
			const newStore = new Store();
			newStore.id = change.id;
			newStore.user = user;
			newStore.data = change.data;
			newStore.modified_at = new Date(change.modified_at);
			newStore.created_at = new Date();
			newStore.type = change.type;
			newStore.name = change.name;
			await newStore.save();
			continue;
		}
		if (store.user.id !== user.id) {
			// Not the owner of this store
			changes.push(store); // Send back the store to the client to overwrite their changes
			continue;
		}
		store.data = change.data;
		store.modified_at = new Date(change.modified_at);
		await store.save();
	}

	const friends = await getFriends(user);

	const selector = [{ id: user.id }];
	for (const friend of friends) {
		selector.push({ id: friend.id });
	}

	// Find stores that are out of date on the client
	const allStores = await Store.find({ where: { user: selector }, relations: { user: true } }); // TODO: use SQL query to only get modified stores
	for (const store of allStores) {
		if (store.user.id !== user.id && !sharedStoreTypes.includes(store.type)) {
			// Not the owner of this store and not a shared type
			continue;
		}

		const clientStore = payload.stores.find((s) => s.id === store.id);
		if (!clientStore || new Date(clientStore.modified_at) < store.modified_at) {
			changes.push(store); // Client doesn't have this store or it's out of date
		}
	}

	// Send "null" change for stores that aren't owned by the user or their friends
	for (const clientStore of payload.stores) {
		if (
			!allStores.find((s) => s.id === clientStore.id) &&
			(!user.id ||
				!friends.find((f) => f.id === clientStore.id)) // Not owned by user or their friends
		) {
			const deletedStore = new Store();
			deletedStore.id = clientStore.id;
			deletedStore.data = "null";
			deletedStore.modified_at = new Date();
			deletedStore.created_at = new Date();
			deletedStore.type = "location"; // Type doesn't matter, data is null
			deletedStore.name = "";
			changes.push(deletedStore);
		}
	}

	return { changes };
}