// RPC implementation + calling — template
//
// Docs: https://opencode.ai/v2/docs/build/plugins/rpc/
//
// Two files. The contract is importable without loading the implementation, so
// other plugins and clients can depend on it.
//
// Needs templates/rpc.ts copied next to this file as src/rpc.ts, so the
// doc's "./rpc.js" specifier resolves. An Effect plugin would import the
// Effect-dialect contract instead — see rpc-effect.ts.

//
// The docs use "@opencode/plugin" and "@opencode/plugin/effect". Install the
// package at your OpenCode version and restart the service first — see the
// PREREQUISITE block in promise-plugin.ts.
import { Plugin } from "@opencode/plugin"
import { Acme } from "./rpc.js"

export default Plugin.define({
  id: "acme-plugin",

  async setup(ctx) {
    const registration = await ctx.rpc.register(Acme, {
      search: async (input, context) => {
        // JSON Schema input is `unknown` — narrow it.
        const { query } = input as { query: string }

        // `signal` cancels with the request; `context.error` declares a failure.
        const text = await findText(query, { signal: context.signal })
        if (!text) return context.error("not_found", "Result not found", { query })

        return { text }
      },
    })

    // The same plugin can call its own RPC once registered.
    const acme = ctx.rpc(Acme)
    // Raw JSON Schema output arrives as `unknown` in the Promise flavor; the
    // docs say to narrow it.
    const result = (await acme.search({ query: "hello" })) as { text: string }

    // Emit to subscribers.
    await registration.events.emit("updated", { itemID: "item-1", text: result.text })

    // ---------------------------------------------------------------- events
    // Subscribe with the LOCAL name. The received `type` is prefixed
    // ("rpc.acme.updated"). Every event carries `data` and `location`.
    //
    // Subscriptions are LIVE ONLY: a disconnected subscriber misses events.
    // Plugin unload closes them.
    //
    // const unsubscribe = acme.events.on("updated", (event) => {
    //   console.log(event.type, event.location.directory, event.data.text)
    // })
    // unsubscribe()
    //
    // for await (const event of acme.events.subscribe("updated")) {
    //   console.log(event.data.text)
    // }

    return () => {
      void registration.dispose()
    }
  },
})

// Calling from a client over HTTP:
//   import { OpenCode } from "@opencode/client"
//   import { Acme } from "opencode-acme-plugin/rpc"
//   const client = OpenCode.make({ baseUrl: "http://localhost:4096" })
//   const acme = client.rpc(Acme)
//   const result = await acme.search({ query: "hello" })

// Calling from another plugin (a TUI plugin uses `context.client`):
//   import { Plugin } from "@opencode/plugin/tui"
//   const acme = context.client.rpc(Acme)
//   const result = await acme.search({ query: "hello" })

declare function findText(query: string, options: { signal: AbortSignal }): Promise<string | undefined>