package testrunner

import (
	"context"
	"fmt"
	"time"

	"alox.tool/api"
	"alox.tool/eventbus"
	"alox.tool/uart"
)

type TestRunner struct {
	bus eventbus.EventBus
	com *uart.Com
}

func New(bus eventbus.EventBus, com *uart.Com) *TestRunner {
	return &TestRunner{
		bus: bus,
		com: com,
	}
}

func (tr *TestRunner) Expect(idToSend byte, payload []byte, expectedID byte, timeout time.Duration) (*api.Frame, error) {
	rxChan := tr.bus.Subscribe(api.TopicUARTRx)
	defer tr.bus.Unsubscribe(api.TopicUARTRx, rxChan)

	if err := tr.com.Send(idToSend, payload); err != nil {
		return nil, fmt.Errorf("send error: %w", err)
	}

	ctx, cancel := context.WithTimeout(context.Background(), timeout)
	defer cancel()

	for {
		select {
		case <-ctx.Done():
			return nil, fmt.Errorf("timeout waiting for ID 0x%02X", expectedID)
		case frame := <-rxChan:
			f := frame.(api.Frame)
			if f.ID == expectedID {
				return &f, nil
			}
			// Ignore other IDs and Messages on the Bus
		}
	}
}