import type { WsClientMessage, WsServerMessage } from "@dispatch/transport-contract";
import type { AgentEvent, Chunk } from "@dispatch/wire";

/**
 * Compile-time exhaustiveness guard for `AgentEvent.type`.
 * If a variant is added/removed/renamed in `@dispatch/wire`, this function's
 * default branch becomes reachable → TypeScript error at build time.
 */
export function assertAgentEventExhaustive(event: AgentEvent): string {
  switch (event.type) {
    case "status":
      return "status";
    case "turn-start":
      return "turn-start";
    case "user-message":
      return "user-message";
    case "text-delta":
      return "text-delta";
    case "reasoning-delta":
      return "reasoning-delta";
    case "reasoning-end":
      return "reasoning-end";
    case "tool-call":
      return "tool-call";
    case "tool-result":
      return "tool-result";
    case "tool-output":
      return "tool-output";
    case "usage":
      return "usage";
    case "error":
      return "error";
    case "done":
      return "done";
    case "turn-sealed":
      return "turn-sealed";
    case "turn-ended":
      return "turn-ended";
    case "step-complete":
      return "step-complete";
    case "steering":
      return "steering";
    case "provider-retry":
      return "provider-retry";
    default:
      return event satisfies never;
  }
}

/**
 * Compile-time exhaustiveness guard for `Chunk.type`.
 */
export function assertChunkExhaustive(chunk: Chunk): string {
  switch (chunk.type) {
    case "text":
      return "text";
    case "thinking":
      return "thinking";
    case "tool-call":
      return "tool-call";
    case "tool-result":
      return "tool-result";
    case "error":
      return "error";
    case "system":
      return "system";
    case "image":
      return "image";
    default:
      return chunk satisfies never;
  }
}

/**
 * Compile-time exhaustiveness guard for `WsServerMessage.type`.
 * Covers both surface ops and chat ops.
 */
export function assertWsServerMessageExhaustive(msg: WsServerMessage): string {
  switch (msg.type) {
    case "catalog":
      return "catalog";
    case "surface":
      return "surface";
    case "update":
      return "update";
    case "error":
      return "error";
    case "chat.delta":
      return "chat.delta";
    case "chat.resync-required":
      return "chat.resync-required";
    case "chat.accepted":
      return "chat.accepted";
    case "chat.subscription-rejected":
      return "chat.subscription-rejected";
    case "chat.queued":
      return "chat.queued";
    case "chat.error":
      return "chat.error";
    case "conversation.open":
      return "conversation.open";
    case "conversation.statusChanged":
      return "conversation.statusChanged";
    case "conversation.compacted":
      return "conversation.compacted";
    case "conversation.tabGroupChanged":
      return "conversation.tabGroupChanged";
    case "extensions-changed":
      return "extensions-changed";
    case "layout":
      return "layout";
    case "tile-layout":
      return "tile-layout";
    default:
      return msg satisfies never;
  }
}

/**
 * Compile-time exhaustiveness guard for `WsClientMessage.type`.
 * Covers both surface ops and chat ops.
 */
export function assertWsClientMessageExhaustive(msg: WsClientMessage): string {
  switch (msg.type) {
    case "subscribe":
      return "subscribe";
    case "unsubscribe":
      return "unsubscribe";
    case "invoke":
      return "invoke";
    case "chat.send":
      return "chat.send";
    case "chat.subscribe":
      return "chat.subscribe";
    case "chat.unsubscribe":
      return "chat.unsubscribe";
    case "chat.queue":
      return "chat.queue";
    case "chat.queue.cancel":
      return "chat.queue.cancel";
    case "workspace.set":
      return "workspace.set";
    default:
      return msg satisfies never;
  }
}