import { describe, expect, it } from 'vitest'
import { SSEEventParser } from '../../src/utils/sse-session/sse-event-parser.js'
import { SSESession } from '../../src/utils/sse-session/sse-session.js'

const encode = (text: string) => new TextEncoder().encode(text)

describe('vendored sse-session', () => {
  it('parses events across arbitrary chunk boundaries', () => {
    const parser = new SSEEventParser()
    const text = 'id: 1\nevent: change\ndata: {"a":1}\n\n: comment\ndata: line1\ndata: line2\n\n'
    const events = []
    for (let i = 0; i < text.length; i += 3) events.push(...parser.parseEvents(encode(text.slice(i, i + 3))))
    expect(events).toEqual([{ id: '1', event: 'change', data: '{"a":1}' }, { data: 'line1\nline2' }])
  })

  it('connects, delivers messages and reconnects when persistent', async () => {
    let connections = 0
    const session = new SSESession('http://test/events', {
      persistent: true,
      fetch: async () => {
        connections++
        return new Response(encode(`data: hello ${connections}\n\n`))
      },
    })
    const received: string[] = []
    session.on('message', (m) => received.push(m.data))
    await session.connect()
    await session.waitFor('message', (m) => m.data === 'hello 2')
    await session.disconnect()
    expect(received.slice(0, 2)).toEqual(['hello 1', 'hello 2'])
  })
})