import * as oak from 'jsr:@oak/oak'
import * as contracts from '../src/contracts.ts'
import * as adapter_base from './mod.ts'
import {ClientRealtimeEmitter, ApiController, ClientRequest} from '../server.ts'
type OakRouterContext = oak.RouterContext<string, Record<string | number, string>, Record<string, any>>

type OakRouterFunction = (ctx: OakRouterContext) => Promise
class ServerSentEventsAdapter extends adapter_base.ServerSentEventsAdapter {

#status_resolved: PromiseWithResolvers

#target: oak.ServerSentEventTarget
constructor(target: oak.ServerSentEventTarget) {

super()

this.#target = target

this.#status_resolved = Promise.withResolvers()

target.addEventListener('close', e => {

this.#status_resolved.resolve()

})

}
get status() {

return this.#status_resolved.promise

}
send(contract: contracts.EventContract) {

const success = this.#target.dispatchMessage(JSON.stringify(contract))

if (!success) {

throw new Error(Failed to dispatch message over server sent events adapter ${this.#target})

}

}

}
class ServerAdapter extends adapter_base.ServerAdapter {

async handle_server_sent_events_request(ctx: OakRouterContext) {

// TODO error out if x-rpc-connection-id is already present?

const target = await ctx.sendEvents()

const sse_adapter = new ServerSentEventsAdapter(target)
this.add_realtime_client(sse_adapter)

}
async handle_rpc_request(ctx: OakRouterContext) {

const request_contract: contracts.RequestContract = await ctx.request.body.json()

const connection_id = ctx.request.headers.get('x-rpc-connection-id')

const rpc_controller = this.load_controller(request_contract.namespace, connection_id)

const response_contract = await this.handle_request(rpc_controller, request_contract)

ctx.response.body = response_contract

}
static adapt<C, E>(rpc_class: typeof ApiController<C, E, any>, context: C): OakRouterFunction {

const adapter = new ServerAdapter(rpc_class, context)
return async (ctx: OakRouterContext) => {
  if (ctx.request.headers.get('accept') === 'text/event-stream') {
    await adapter.handle_server_sent_events_request(ctx)
  } else {
    await adapter.handle_rpc_request(ctx)
  }
}

}

}
export const adapt = ServerAdapter.adapt

export * from '../server.ts'