package shopfront_test

import (
	"context"
	"os"
	"os/exec"
	"time"

	"github.com/go-redis/redis/v8"
	"github.com/stretchr/testify/require"

	"gitlab.com/manytask/itmo-go/private/tools/testtool"
)

type testingTB interface {
	Logf(format string, args ...interface{})
	Fatalf(format string, args ...interface{})
	Errorf(format string, args ...interface{})
	FailNow()
	Cleanup(func())
}

func StartRedis(tb testingTB) string {
	if redis, ok := os.LookupEnv("REDIS"); ok {
		tb.Logf("using external redis server; REDIS=%s", redis)
		return redis
	}

	port, err := testtool.GetFreePort()
	require.NoError(tb, err)

	_, err = exec.LookPath("redis-server")
	if err != nil {
		tb.Fatalf("redis-server binary is not found; is redis installed?")
	}

	cmd := exec.Command("redis-server", "--port", port, "--save", "", "--appendonly", "no")
	cmd.Stderr = os.Stderr

	require.NoError(tb, cmd.Start())
	tb.Cleanup(func() {
		_ = cmd.Process.Kill()
	})

	finished := make(chan error, 1)
	go func() {
		finished <- cmd.Wait()
	}()

	redisAddress := "localhost:" + port
	startTimeout := time.After(time.Second * 5)

loop:
	for {
		select {
		case err := <-finished:
			tb.Fatalf("redis server terminated: %v", err)

		case <-startTimeout:
			tb.Fatalf("redis not started after timeout")

		default:
			time.Sleep(time.Millisecond * 50)

			rdb := redis.NewClient(&redis.Options{Addr: redisAddress})
			status := rdb.Ping(context.Background())
			_ = rdb.Close()

			if status.Err() == nil {
				break loop
			}
		}
	}

	return redisAddress
}