package service

import (
	"context"
	"testing"

	"github.com/google/uuid"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"apskel-pos-be/internal/entities"
	"apskel-pos-be/internal/logger"
	"apskel-pos-be/internal/models"
	"apskel-pos-be/internal/repository"
)

type discrepancyFinderFake struct {
	found []repository.WalletDiscrepancy
}

func (f *discrepancyFinderFake) FindDiscrepancies(context.Context, int) ([]repository.WalletDiscrepancy, error) {
	return f.found, nil
}

type orgUsersFake map[uuid.UUID][]*entities.User

func (f orgUsersFake) GetByOrganizationID(_ context.Context, org uuid.UUID) ([]*entities.User, error) {
	return f[org], nil
}

type notifierFake struct {
	sent []*models.SendNotificationRequest
}

func (f *notifierFake) Send(_ context.Context, req *models.SendNotificationRequest) (*models.NotificationResponse, error) {
	f.sent = append(f.sent, req)
	return &models.NotificationResponse{}, nil
}

func TestWalletReconciliationJob(t *testing.T) {
	logger.Setup("fatal", "json")
	org := uuid.New()
	admin, owner, manager, cashier := uuid.New(), uuid.New(), uuid.New(), uuid.New()
	users := orgUsersFake{org: {
		{ID: admin, Role: entities.RoleAdmin},
		{ID: owner, Role: entities.RoleOwner},
		{ID: manager, Role: entities.RoleManager},
		{ID: cashier, Role: entities.RoleCashier},
	}}
	finder := &discrepancyFinderFake{}
	notifier := &notifierFake{}
	job := NewWalletReconciliationJob(finder, users, notifier)
	ctx := context.Background()

	// Consistent data: nothing reported.
	found, err := job.RunOnce(ctx)
	require.NoError(t, err)
	assert.Empty(t, found)
	assert.Empty(t, notifier.sent)

	// A discrepancy notifies the organization's admins, owners and managers.
	customer := uuid.New()
	lot := uuid.New()
	finder.found = []repository.WalletDiscrepancy{
		{Check: repository.WalletCheckBalanceVsLots, OrganizationID: org, CustomerID: customer, Currency: "POINT", Expected: 100, Actual: 105},
		{Check: repository.WalletCheckLotVsAllocations, OrganizationID: org, CustomerID: customer, Currency: "POINT", ObjectID: &lot, Expected: 50, Actual: 55},
	}
	found, err = job.RunOnce(ctx)
	require.NoError(t, err)
	assert.Len(t, found, 2)
	require.Len(t, notifier.sent, 1)
	sent := notifier.sent[0]
	assert.ElementsMatch(t, []uuid.UUID{admin, owner, manager}, sent.ReceiverIDs, "cashiers are not told")
	assert.Equal(t, &org, sent.NotifiableID)
	assert.Equal(t, 2, sent.Data["discrepancies"])
	assert.Equal(t, []string{customer.String()}, sent.Data["customer_ids"])
	assert.Equal(t, entities.NotificationPriorityHigh, sent.Priority)

	// The same problem, still unfixed and in a different order, does not notify again.
	finder.found = []repository.WalletDiscrepancy{finder.found[1], finder.found[0]}
	_, err = job.RunOnce(ctx)
	require.NoError(t, err)
	assert.Len(t, notifier.sent, 1)

	// A changed problem does.
	finder.found = finder.found[:1]
	_, err = job.RunOnce(ctx)
	require.NoError(t, err)
	assert.Len(t, notifier.sent, 2)

	// Once clean the organization is forgotten, so the same problem coming back
	// notifies again.
	previous := finder.found
	finder.found = nil
	_, err = job.RunOnce(ctx)
	require.NoError(t, err)
	assert.Len(t, notifier.sent, 2)
	finder.found = previous
	_, err = job.RunOnce(ctx)
	require.NoError(t, err)
	assert.Len(t, notifier.sent, 3)
}

func TestWalletReconciliationJobStartStop(t *testing.T) {
	logger.Setup("fatal", "json")
	job := NewWalletReconciliationJob(&discrepancyFinderFake{}, orgUsersFake{}, &notifierFake{})
	job.Start(0)
	job.Stop()
	job.Stop() // stopping twice is harmless
}