package diagnostics_test

import (
	"context"
	"testing"
	"time"

	"github.com/ledgerwatch/erigon-lib/diagnostics"
	"github.com/ledgerwatch/log/v3"
)

type testInfo struct {
	count int
}

func (ti testInfo) Type() diagnostics.Type {
	return diagnostics.TypeOf(ti)
}

type testProvider struct {
}

func (t *testProvider) StartDiagnostics(ctx context.Context) error {
	timer := time.NewTicker(1 * time.Second)
	defer timer.Stop()

	var count int

	for {
		select {
		case <-ctx.Done():
			return nil
		case <-timer.C:
			diagnostics.Send(testInfo{count})
			count++
		}
	}
}

func TestProviderRegistration(t *testing.T) {

	// diagnostics provider
	provider := &testProvider{}
	diagnostics.RegisterProvider(provider, diagnostics.TypeOf(testInfo{}), log.Root())

	// diagnostics receiver
	ctx, ch, cancel := diagnostics.Context[testInfo](context.Background(), 1)
	diagnostics.StartProviders(ctx, diagnostics.TypeOf(testInfo{}), log.Root())

	for info := range ch {
		if info.count == 3 {
			cancel()
		}
	}
}

func TestDelayedProviderRegistration(t *testing.T) {

	time.AfterFunc(1*time.Second, func() {
		// diagnostics provider
		provider := &testProvider{}
		diagnostics.RegisterProvider(provider, diagnostics.TypeOf(testInfo{}), log.Root())
	})

	// diagnostics receiver
	ctx, ch, cancel := diagnostics.Context[testInfo](context.Background(), 1)
	diagnostics.StartProviders(ctx, diagnostics.TypeOf(testInfo{}), log.Root())

	for info := range ch {
		if info.count == 3 {
			cancel()
		}
	}
}

func TestProviderFuncRegistration(t *testing.T) {

	// diagnostics provider
	diagnostics.RegisterProvider(diagnostics.ProviderFunc(func(ctx context.Context) error {
		timer := time.NewTicker(1 * time.Second)
		defer timer.Stop()

		var count int

		for {
			select {
			case <-ctx.Done():
				return nil
			case <-timer.C:
				diagnostics.Send(testInfo{count})
				count++
			}
		}
	}), diagnostics.TypeOf(testInfo{}), log.Root())

	// diagnostics receiver
	ctx, ch, cancel := diagnostics.Context[testInfo](context.Background(), 1)

	diagnostics.StartProviders(ctx, diagnostics.TypeOf(testInfo{}), log.Root())

	for info := range ch {
		if info.count == 3 {
			cancel()
		}
	}
}