Refactor v2 session events as schemas (#24512)

packages/opencode/src/v2/event.ts

@@ -0,0 +1,53 @@
+import { Identifier } from "@/id/id"
+import { SyncEvent } from "@/sync"
+import { withStatics } from "@/util/schema"
+import { Flag } from "@opencode-ai/core/flag/flag"
+import * as Schema from "effect/Schema"
+
+export const ID = Schema.String.pipe(
+  Schema.brand("Event.ID"),
+  withStatics((s) => ({
+    create: () => s.make(Identifier.create("evt", "ascending")),
+  })),
+)
+export type ID = Schema.Schema.Type<typeof ID>
+
+export function define<const Type extends string, Fields extends Schema.Struct.Fields>(input: {
+  type: Type
+  schema: Fields
+  aggregate: string
+  version?: number
+}) {
+  const Payload = Schema.Struct({
+    id: ID,
+    metadata: Schema.Record(Schema.String, Schema.Unknown).pipe(Schema.optional),
+    type: Schema.Literal(input.type),
+    data: Schema.Struct(input.schema),
+  }).annotate({
+    identifier: input.type,
+  })
+
+  const Sync = SyncEvent.define({
+    type: input.type,
+    version: input.version ?? 1,
+    aggregate: input.aggregate,
+    schema: Payload.fields.data,
+  })
+
+  return Object.assign(Payload, {
+    Sync,
+    version: input.version,
+    aggregate: input.aggregate,
+  })
+}
+
+export function run<Def extends SyncEvent.Definition>(
+  def: Def,
+  data: SyncEvent.Event<Def>["data"],
+  options?: { publish?: boolean },
+) {
+  if (!Flag.OPENCODE_EXPERIMENTAL_EVENT_SYSTEM) return
+  SyncEvent.run(def, data, options)
+}
+
+export * as EventV2 from "./event"