import { z } from "zod";

/**

* The version number of the matchmaking protocol.

* This number is incremented whenever a backwards-incompatible change is made.

*/

export const PROTOCOL_VERSION = 1;

/** The types of signaling messages one peer can send to another. */

export const MessageType = z.union([

z.literal("offer"),

z.literal("answer"),

z.literal("candidate"),

]);

export type MessageType = z.output<typeof MessageType>;

/** A message sent from a client to the server. */

export const ClientMessage = z.union([

/** Send a WebRTC signaling message to a peer. */

z.object({

kind: z.literal("send-message"),

destinationID: z.string().uuid(),

type: MessageType,

payload: z.any(),

}),

/** Matchmaking request. */

z

.object({

kind: z.literal("match-request"),

gameID: z.string().nonempty(),

maxPlayers: z.number().min(2),

minPlayers: z.number().min(2),

})

.refine((req) => req.maxPlayers >= req.minPlayers),

]);

export type ClientMessage = z.output<typeof ClientMessage>;

/**

* A message sent from the server to the client.

* Server messages don't really need to be validated

* but this could be useful for debugging / unit testing.

*/

export const ServerMessage = z.union([

/** Sent as soon as a client connects in order to inform client of their ID. */

z.object({

kind: z.literal("registration-success"),

clientID: z.string().uuid(),

iceServers: z.any(),

}),

/** An unexpected error occurred on the server side. The connection will be terminated. */

z.object({

kind: z.literal("server-error"),

reason: z.string().nonempty(),

}),

/** A signaling message failed to send. */

z.object({

kind: z.literal("send-message-failure"),

destinationID: z.string().uuid(),

reason: z.string().nonempty(),

}),

/** Deliver a signaling message from a peer. */

z.object({

kind: z.literal("peer-message"),

sourceID: z.string().uuid(),

type: MessageType,

payload: z.any(),

}),

/** Tell the client it should host the match. */

z.object({

kind: z.literal("host-match"),

clientIDs: z.array(z.string().uuid()),

}),

/** Tell the client it should join a match hosted by another player. */

z.object({

kind: z.literal("join-match"),

hostID: z.string().uuid(),

}),

/** Tell the client it's match request failed. */

z.object({

kind: z.literal("match-request-failure"),

reason: z.string().nonempty(),

}),

]);

export type ServerMessage = z.output<typeof ServerMessage>;