package services

import (
	"testing"
	"time"

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

	"github.com/treytartt/casera-api/internal/models"
	"github.com/treytartt/casera-api/internal/repositories"
	"github.com/treytartt/casera-api/internal/testutil"
)

// setupSubscriptionService creates a SubscriptionService with the given
// IAP clients (nil means "not configured"). It bypasses NewSubscriptionService
// which tries to load config from environment.
func setupSubscriptionService(t *testing.T, appleClient *AppleIAPClient, googleClient *GoogleIAPClient) (*SubscriptionService, *repositories.SubscriptionRepository) {
	db := testutil.SetupTestDB(t)

	subscriptionRepo := repositories.NewSubscriptionRepository(db)
	residenceRepo := repositories.NewResidenceRepository(db)
	taskRepo := repositories.NewTaskRepository(db)
	contractorRepo := repositories.NewContractorRepository(db)
	documentRepo := repositories.NewDocumentRepository(db)

	// Create a test user and subscription record for the test
	user := testutil.CreateTestUser(t, db, "subuser", "subuser@test.com", "password")

	// Create subscription record so GetOrCreate will find it
	sub := &models.UserSubscription{
		UserID: user.ID,
		Tier:   models.TierFree,
	}
	err := db.Create(sub).Error
	require.NoError(t, err)

	svc := &SubscriptionService{
		subscriptionRepo: subscriptionRepo,
		residenceRepo:    residenceRepo,
		taskRepo:         taskRepo,
		contractorRepo:   contractorRepo,
		documentRepo:     documentRepo,
		appleClient:      appleClient,
		googleClient:     googleClient,
	}

	return svc, subscriptionRepo
}

func TestProcessApplePurchase_ClientNil_ReturnsError(t *testing.T) {
	db := testutil.SetupTestDB(t)
	subscriptionRepo := repositories.NewSubscriptionRepository(db)
	residenceRepo := repositories.NewResidenceRepository(db)
	taskRepo := repositories.NewTaskRepository(db)
	contractorRepo := repositories.NewContractorRepository(db)
	documentRepo := repositories.NewDocumentRepository(db)

	user := testutil.CreateTestUser(t, db, "subuser", "subuser@test.com", "password")
	sub := &models.UserSubscription{UserID: user.ID, Tier: models.TierFree}
	require.NoError(t, db.Create(sub).Error)

	svc := &SubscriptionService{
		subscriptionRepo: subscriptionRepo,
		residenceRepo:    residenceRepo,
		taskRepo:         taskRepo,
		contractorRepo:   contractorRepo,
		documentRepo:     documentRepo,
		appleClient:      nil, // Not configured
		googleClient:     nil,
	}

	_, err := svc.ProcessApplePurchase(user.ID, "fake-receipt", "")
	assert.Error(t, err, "ProcessApplePurchase should return error when Apple IAP client is nil")

	// Verify user was NOT upgraded to Pro
	updatedSub, err := subscriptionRepo.GetOrCreate(user.ID)
	require.NoError(t, err)
	assert.Equal(t, models.TierFree, updatedSub.Tier, "User should remain on free tier when IAP client is nil")
}

func TestProcessApplePurchase_ValidationFails_DoesNotUpgrade(t *testing.T) {
	// We cannot easily create a real AppleIAPClient that will fail validation
	// in a unit test (it requires real keys and network access).
	// Instead, we test the code path logic:
	// When appleClient is nil, the service must NOT upgrade the user.
	// This is the same as TestProcessApplePurchase_ClientNil_ReturnsError
	// but validates no fallback occurs for the specific case.

	db := testutil.SetupTestDB(t)
	subscriptionRepo := repositories.NewSubscriptionRepository(db)
	residenceRepo := repositories.NewResidenceRepository(db)
	taskRepo := repositories.NewTaskRepository(db)
	contractorRepo := repositories.NewContractorRepository(db)
	documentRepo := repositories.NewDocumentRepository(db)

	user := testutil.CreateTestUser(t, db, "subuser2", "subuser2@test.com", "password")
	sub := &models.UserSubscription{UserID: user.ID, Tier: models.TierFree}
	require.NoError(t, db.Create(sub).Error)

	svc := &SubscriptionService{
		subscriptionRepo: subscriptionRepo,
		residenceRepo:    residenceRepo,
		taskRepo:         taskRepo,
		contractorRepo:   contractorRepo,
		documentRepo:     documentRepo,
		appleClient:      nil,
		googleClient:     nil,
	}

	// Neither receipt data nor transaction ID - should still not grant Pro
	_, err := svc.ProcessApplePurchase(user.ID, "", "")
	assert.Error(t, err, "ProcessApplePurchase should return error when client is nil, even with empty data")

	// Verify no upgrade happened
	updatedSub, err := subscriptionRepo.GetOrCreate(user.ID)
	require.NoError(t, err)
	assert.Equal(t, models.TierFree, updatedSub.Tier, "User should remain on free tier")
}

func TestProcessGooglePurchase_ClientNil_ReturnsError(t *testing.T) {
	db := testutil.SetupTestDB(t)
	subscriptionRepo := repositories.NewSubscriptionRepository(db)
	residenceRepo := repositories.NewResidenceRepository(db)
	taskRepo := repositories.NewTaskRepository(db)
	contractorRepo := repositories.NewContractorRepository(db)
	documentRepo := repositories.NewDocumentRepository(db)

	user := testutil.CreateTestUser(t, db, "subuser3", "subuser3@test.com", "password")
	sub := &models.UserSubscription{UserID: user.ID, Tier: models.TierFree}
	require.NoError(t, db.Create(sub).Error)

	svc := &SubscriptionService{
		subscriptionRepo: subscriptionRepo,
		residenceRepo:    residenceRepo,
		taskRepo:         taskRepo,
		contractorRepo:   contractorRepo,
		documentRepo:     documentRepo,
		appleClient:      nil,
		googleClient:     nil, // Not configured
	}

	_, err := svc.ProcessGooglePurchase(user.ID, "fake-token", "com.tt.casera.pro.monthly")
	assert.Error(t, err, "ProcessGooglePurchase should return error when Google IAP client is nil")

	// Verify user was NOT upgraded to Pro
	updatedSub, err := subscriptionRepo.GetOrCreate(user.ID)
	require.NoError(t, err)
	assert.Equal(t, models.TierFree, updatedSub.Tier, "User should remain on free tier when IAP client is nil")
}

func TestProcessGooglePurchase_ValidationFails_DoesNotUpgrade(t *testing.T) {
	db := testutil.SetupTestDB(t)
	subscriptionRepo := repositories.NewSubscriptionRepository(db)
	residenceRepo := repositories.NewResidenceRepository(db)
	taskRepo := repositories.NewTaskRepository(db)
	contractorRepo := repositories.NewContractorRepository(db)
	documentRepo := repositories.NewDocumentRepository(db)

	user := testutil.CreateTestUser(t, db, "subuser4", "subuser4@test.com", "password")
	sub := &models.UserSubscription{UserID: user.ID, Tier: models.TierFree}
	require.NoError(t, db.Create(sub).Error)

	svc := &SubscriptionService{
		subscriptionRepo: subscriptionRepo,
		residenceRepo:    residenceRepo,
		taskRepo:         taskRepo,
		contractorRepo:   contractorRepo,
		documentRepo:     documentRepo,
		appleClient:      nil,
		googleClient:     nil, // Not configured
	}

	// With empty token
	_, err := svc.ProcessGooglePurchase(user.ID, "", "")
	assert.Error(t, err, "ProcessGooglePurchase should return error when client is nil")

	// Verify no upgrade happened
	updatedSub, err := subscriptionRepo.GetOrCreate(user.ID)
	require.NoError(t, err)
	assert.Equal(t, models.TierFree, updatedSub.Tier, "User should remain on free tier")
}

func TestIsAlreadyProFromOtherPlatform(t *testing.T) {
	future := time.Now().UTC().Add(30 * 24 * time.Hour)

	tests := []struct {
		name              string
		tier              models.SubscriptionTier
		platform          string
		expiresAt         *time.Time
		trialEnd          *time.Time
		requestedPlatform string
		wantConflict      bool
		wantPlatform      string
	}{
		{
			name:              "free user returns no conflict",
			tier:              models.TierFree,
			platform:          "",
			expiresAt:         nil,
			trialEnd:          nil,
			requestedPlatform: "stripe",
			wantConflict:      false,
			wantPlatform:      "",
		},
		{
			name:              "pro from ios, requesting ios returns no conflict (same platform)",
			tier:              models.TierPro,
			platform:          "ios",
			expiresAt:         &future,
			trialEnd:          nil,
			requestedPlatform: "ios",
			wantConflict:      false,
			wantPlatform:      "",
		},
		{
			name:              "pro from ios, requesting stripe returns conflict",
			tier:              models.TierPro,
			platform:          "ios",
			expiresAt:         &future,
			trialEnd:          nil,
			requestedPlatform: "stripe",
			wantConflict:      true,
			wantPlatform:      "ios",
		},
		{
			name:              "pro from stripe, requesting android returns conflict",
			tier:              models.TierPro,
			platform:          "stripe",
			expiresAt:         &future,
			trialEnd:          nil,
			requestedPlatform: "android",
			wantConflict:      true,
			wantPlatform:      "stripe",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			db := testutil.SetupTestDB(t)

			subscriptionRepo := repositories.NewSubscriptionRepository(db)
			residenceRepo := repositories.NewResidenceRepository(db)
			taskRepo := repositories.NewTaskRepository(db)
			contractorRepo := repositories.NewContractorRepository(db)
			documentRepo := repositories.NewDocumentRepository(db)

			svc := &SubscriptionService{
				subscriptionRepo: subscriptionRepo,
				residenceRepo:    residenceRepo,
				taskRepo:         taskRepo,
				contractorRepo:   contractorRepo,
				documentRepo:     documentRepo,
			}

			user := testutil.CreateTestUser(t, db, "owner", "owner@test.com", "password")
			sub := &models.UserSubscription{
				UserID:    user.ID,
				Tier:      tt.tier,
				Platform:  tt.platform,
				ExpiresAt: tt.expiresAt,
				TrialEnd:  tt.trialEnd,
			}
			err := db.Create(sub).Error
			require.NoError(t, err)

			conflict, existingPlatform, err := svc.IsAlreadyProFromOtherPlatform(user.ID, tt.requestedPlatform)
			require.NoError(t, err)
			assert.Equal(t, tt.wantConflict, conflict)
			assert.Equal(t, tt.wantPlatform, existingPlatform)
		})
	}
}