package batcher

import (
	"context"
	"sync/atomic"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"go.uber.org/zap"

	"github.com/dbiz/cdp/ingestion/bulker/internal/model"
)

func TestBatcher_FlushesOnSizeCap(t *testing.T) {
	var flushed int32
	flush := func(_ context.Context, evs []*model.IngestedEvent) error {
		atomic.AddInt32(&flushed, int32(len(evs)))
		return nil
	}
	b := New(3, time.Hour, flush, zap.NewNop())
	for i := 0; i < 3; i++ {
		_ = b.Add(context.Background(), &model.IngestedEvent{MessageID: "x"})
	}
	assert.Equal(t, int32(3), atomic.LoadInt32(&flushed))
}

func TestBatcher_FlushNow_NoOpOnEmpty(t *testing.T) {
	var called int32
	flush := func(_ context.Context, _ []*model.IngestedEvent) error {
		atomic.AddInt32(&called, 1)
		return nil
	}
	b := New(10, time.Hour, flush, zap.NewNop())
	_ = b.FlushNow(context.Background())
	assert.Equal(t, int32(0), atomic.LoadInt32(&called))
}

func TestBatcher_FlushesOnTimer(t *testing.T) {
	var flushed int32
	flush := func(_ context.Context, evs []*model.IngestedEvent) error {
		atomic.AddInt32(&flushed, int32(len(evs)))
		return nil
	}
	b := New(1000, 50*time.Millisecond, flush, zap.NewNop())
	ctx, cancel := context.WithCancel(context.Background())
	go b.Run(ctx)

	_ = b.Add(context.Background(), &model.IngestedEvent{MessageID: "a"})
	_ = b.Add(context.Background(), &model.IngestedEvent{MessageID: "b"})

	time.Sleep(120 * time.Millisecond)
	cancel()
	time.Sleep(10 * time.Millisecond)
	assert.Equal(t, int32(2), atomic.LoadInt32(&flushed))
}