package sqlite_test

import (
	"context"
	"database/sql"
	"encoding/base64"
	"errors"
	"sync"
	"testing"
	"time"

	"cmroubao/backend-api/internal/domain"
	"cmroubao/backend-api/internal/platform/migration"
	"cmroubao/backend-api/internal/platform/password"
	repository "cmroubao/backend-api/internal/repository/sqlite"
	"cmroubao/backend-api/internal/usecase"

	"golang.org/x/crypto/bcrypt"
)

func TestAuthRepositoryPersistsOnlyHashesAndRevokesAdminSession(
	t *testing.T,
) {
	db := openDatabase(t)
	service := newRepositoryAuthService(t, db)
	ctx := context.Background()
	admin, err := service.ProvisionUser(ctx, usecase.ProvisionUserCommand{
		Username: "admin",
		Password: "admin-password",
		Role:     domain.UserRoleAdmin,
		Active:   true,
	})
	if err != nil {
		t.Fatalf("ProvisionUser() error = %v", err)
	}
	var passwordHash string
	if err := db.QueryRow(
		"SELECT password_hash FROM users WHERE id = ?",
		admin.ID,
	).Scan(&passwordHash); err != nil {
		t.Fatalf("query password hash: %v", err)
	}
	if passwordHash == "admin-password" || passwordHash == "" {
		t.Fatal("database contains missing or plaintext password")
	}

	login, err := service.LoginAdmin(ctx, usecase.LoginAdminCommand{
		Username: "admin",
		Password: "admin-password",
	})
	if err != nil {
		t.Fatalf("LoginAdmin() error = %v", err)
	}
	var storedTokenHash string
	if err := db.QueryRow(
		"SELECT token_hash FROM admin_sessions WHERE user_id = ?",
		admin.ID,
	).Scan(&storedTokenHash); err != nil {
		t.Fatalf("query token hash: %v", err)
	}
	if storedTokenHash == login.Token || len(storedTokenHash) != 64 {
		t.Fatal("database contains missing or plaintext admin token")
	}
	principal, err := service.AuthenticateAdmin(ctx, login.Token)
	if err != nil {
		t.Fatalf("AuthenticateAdmin() error = %v", err)
	}
	if principal.UserID != admin.ID ||
		principal.Role != domain.UserRoleAdmin ||
		principal.DeviceID != "" {
		t.Fatalf("AuthenticateAdmin() principal = %+v", principal)
	}
	if err := service.SetUserActive(
		ctx,
		usecase.SetUserActiveCommand{
			Username: admin.Username,
			Active:   false,
		},
	); err != nil {
		t.Fatalf("disable admin: %v", err)
	}
	_, err = service.AuthenticateAdmin(ctx, login.Token)
	assertRepositoryAuthCode(
		t,
		err,
		"AUTH_ACCOUNT_OR_DEVICE_DISABLED",
	)
	if err := service.SetUserActive(
		ctx,
		usecase.SetUserActiveCommand{
			Username: admin.Username,
			Active:   true,
		},
	); err != nil {
		t.Fatalf("enable admin: %v", err)
	}
	if _, err := db.Exec(
		"UPDATE admin_sessions SET expires_at = ? WHERE user_id = ?",
		time.Date(2000, 1, 1, 0, 0, 0, 0, time.UTC).Format(
			time.RFC3339Nano,
		),
		admin.ID,
	); err != nil {
		t.Fatalf("expire admin session: %v", err)
	}
	_, err = service.AuthenticateAdmin(ctx, login.Token)
	assertRepositoryAuthCode(t, err, "AUTH_SESSION_EXPIRED")
	if _, err := db.Exec(
		"UPDATE admin_sessions SET expires_at = ? WHERE user_id = ?",
		login.ExpiresAt.Format(time.RFC3339Nano),
		admin.ID,
	); err != nil {
		t.Fatalf("restore admin expiry: %v", err)
	}
	if err := service.LogoutAdmin(ctx, login.Token); err != nil {
		t.Fatalf("LogoutAdmin() error = %v", err)
	}
	_, err = service.AuthenticateAdmin(ctx, login.Token)
	assertRepositoryAuthCode(t, err, "AUTH_INVALID_TOKEN")
}

func TestAuthRepositoryFirstBuyerBindingIsAtomicAndPersistent(
	t *testing.T,
) {
	db := openDatabase(t)
	service := newRepositoryAuthService(t, db)
	ctx := context.Background()
	for _, username := range []string{"buyer-a", "buyer-b"} {
		if _, err := service.ProvisionUser(
			ctx,
			usecase.ProvisionUserCommand{
				Username: username,
				Password: "buyer-password",
				Role:     domain.UserRoleBuyer,
				Active:   true,
			},
		); err != nil {
			t.Fatalf("ProvisionUser(%s) error = %v", username, err)
		}
	}
	device, err := service.ProvisionDevice(
		ctx,
		usecase.ProvisionDeviceCommand{
			Name:    "PDD test device",
			Enabled: true,
		},
	)
	if err != nil {
		t.Fatalf("ProvisionDevice() error = %v", err)
	}
	var storedDeviceTokenHash string
	if err := db.QueryRow(
		"SELECT token_hash FROM devices WHERE id = ?",
		device.Device.ID,
	).Scan(&storedDeviceTokenHash); err != nil {
		t.Fatalf("query device token hash: %v", err)
	}
	if storedDeviceTokenHash == device.DeviceToken ||
		len(storedDeviceTokenHash) != 64 {
		t.Fatal("database contains missing or plaintext device token")
	}

	start := make(chan struct{})
	results := make(chan usecase.AccessTokenResult, 2)
	failures := make(chan error, 2)
	var wait sync.WaitGroup
	for _, username := range []string{"buyer-a", "buyer-b"} {
		username := username
		wait.Add(1)
		go func() {
			defer wait.Done()
			<-start
			result, err := service.LoginBuyerDevice(
				ctx,
				usecase.LoginBuyerDeviceCommand{
					Username:       username,
					Password:       "buyer-password",
					DeviceID:       device.Device.ID,
					DeviceToken:    device.DeviceToken,
					AppVersion:     "0.1.0",
					AndroidVersion: "16",
				},
			)
			if err != nil {
				failures <- err
				return
			}
			results <- result
		}()
	}
	close(start)
	wait.Wait()
	close(results)
	close(failures)

	if len(results) != 1 || len(failures) != 1 {
		t.Fatalf(
			"concurrent binding successes=%d failures=%d, want 1/1",
			len(results),
			len(failures),
		)
	}
	success := <-results
	failure := <-failures
	assertRepositoryAuthCode(t, failure, "AUTH_FORBIDDEN")

	principal, err := service.AuthenticateAccessToken(ctx, success.Token)
	if err != nil {
		t.Fatalf("AuthenticateAccessToken() error = %v", err)
	}
	if principal.DeviceID != device.Device.ID ||
		principal.UserID != success.User.ID {
		t.Fatalf("access principal = %+v", principal)
	}
	if success.Device.AppVersion == nil ||
		*success.Device.AppVersion != "0.1.0" ||
		success.Device.AndroidVersion == nil ||
		*success.Device.AndroidVersion != "16" {
		t.Fatalf("device versions = %+v", success.Device)
	}
	var appVersion string
	var androidVersion string
	var pddVersion sql.NullString
	if err := db.QueryRow(
		`SELECT app_version, android_version, pdd_version
		FROM devices WHERE id = ?`,
		device.Device.ID,
	).Scan(&appVersion, &androidVersion, &pddVersion); err != nil {
		t.Fatalf("query device versions: %v", err)
	}
	if appVersion != "0.1.0" ||
		androidVersion != "16" ||
		pddVersion.Valid {
		t.Fatalf(
			"stored versions app=%q android=%q pdd=%v",
			appVersion,
			androidVersion,
			pddVersion,
		)
	}
	var boundUserID string
	if err := db.QueryRow(
		"SELECT bound_user_id FROM devices WHERE id = ?",
		device.Device.ID,
	).Scan(&boundUserID); err != nil {
		t.Fatalf("query bound user: %v", err)
	}
	if boundUserID != success.User.ID {
		t.Fatalf("bound user = %s, want %s", boundUserID, success.User.ID)
	}
	var storedTokenHash string
	if err := db.QueryRow(
		"SELECT token_hash FROM access_tokens WHERE user_id = ?",
		success.User.ID,
	).Scan(&storedTokenHash); err != nil {
		t.Fatalf("query access token hash: %v", err)
	}
	if storedTokenHash == success.Token || len(storedTokenHash) != 64 {
		t.Fatal("database contains missing or plaintext access token")
	}
}

func TestAuthRepositoryRechecksCurrentUserDeviceAndExpiryState(
	t *testing.T,
) {
	db := openDatabase(t)
	service := newRepositoryAuthService(t, db)
	ctx := context.Background()
	user, err := service.ProvisionUser(ctx, usecase.ProvisionUserCommand{
		Username: "buyer",
		Password: "buyer-password",
		Role:     domain.UserRoleBuyer,
		Active:   true,
	})
	if err != nil {
		t.Fatalf("ProvisionUser() error = %v", err)
	}
	device, err := service.ProvisionDevice(
		ctx,
		usecase.ProvisionDeviceCommand{Name: "Device", Enabled: true},
	)
	if err != nil {
		t.Fatalf("ProvisionDevice() error = %v", err)
	}
	login, err := service.LoginBuyerDevice(
		ctx,
		usecase.LoginBuyerDeviceCommand{
			Username:       user.Username,
			Password:       "buyer-password",
			DeviceID:       device.Device.ID,
			DeviceToken:    device.DeviceToken,
			AppVersion:     "0.1.0",
			AndroidVersion: "16",
		},
	)
	if err != nil {
		t.Fatalf("LoginBuyerDevice() error = %v", err)
	}

	if err := service.SetUserActive(
		ctx,
		usecase.SetUserActiveCommand{
			Username: user.Username,
			Active:   false,
		},
	); err != nil {
		t.Fatalf("disable user: %v", err)
	}
	_, err = service.AuthenticateAccessToken(ctx, login.Token)
	assertRepositoryAuthCode(
		t,
		err,
		"AUTH_ACCOUNT_OR_DEVICE_DISABLED",
	)

	if err := service.SetUserActive(
		ctx,
		usecase.SetUserActiveCommand{
			Username: user.Username,
			Active:   true,
		},
	); err != nil {
		t.Fatalf("enable user: %v", err)
	}
	if err := service.SetDeviceEnabled(
		ctx,
		usecase.SetDeviceEnabledCommand{
			DeviceID: device.Device.ID,
			Enabled:  false,
		},
	); err != nil {
		t.Fatalf("disable device: %v", err)
	}
	_, err = service.AuthenticateAccessToken(ctx, login.Token)
	assertRepositoryAuthCode(
		t,
		err,
		"AUTH_ACCOUNT_OR_DEVICE_DISABLED",
	)

	if err := service.SetDeviceEnabled(
		ctx,
		usecase.SetDeviceEnabledCommand{
			DeviceID: device.Device.ID,
			Enabled:  true,
		},
	); err != nil {
		t.Fatalf("enable device: %v", err)
	}
	if _, err := db.Exec(
		"UPDATE access_tokens SET expires_at = ? WHERE user_id = ?",
		time.Date(2000, 1, 1, 0, 0, 0, 0, time.UTC).Format(
			time.RFC3339Nano,
		),
		user.ID,
	); err != nil {
		t.Fatalf("expire access token: %v", err)
	}
	_, err = service.AuthenticateAccessToken(ctx, login.Token)
	assertRepositoryAuthCode(t, err, "AUTH_SESSION_EXPIRED")

	if _, err := db.Exec(
		`UPDATE access_tokens
		SET expires_at = ?, revoked_at = ?
		WHERE user_id = ?`,
		login.ExpiresAt.Format(time.RFC3339Nano),
		time.Date(2026, 7, 26, 12, 30, 0, 0, time.UTC).Format(
			time.RFC3339Nano,
		),
		user.ID,
	); err != nil {
		t.Fatalf("revoke access token: %v", err)
	}
	_, err = service.AuthenticateAccessToken(ctx, login.Token)
	assertRepositoryAuthCode(t, err, "AUTH_INVALID_TOKEN")
}

func TestAuthMigrationCanRollbackWithoutRebuildingPurchaseTasks(
	t *testing.T,
) {
	db := openDatabase(t)
	runner, err := migration.New(db)
	if err != nil {
		t.Fatalf("migration.New() error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v16) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v15) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v14) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v13) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v12) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v11) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v10) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v9) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v8) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v7) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v6) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v5) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v4) error = %v", err)
	}
	if err := runner.Down(context.Background()); err != nil {
		t.Fatalf("Down(v3) error = %v", err)
	}
	if tableExists(t, db, "users") {
		t.Fatal("users table exists after auth migration rollback")
	}
	if columnExists(t, db, "purchase_tasks", "created_by_user_id") {
		t.Fatal("created_by_user_id exists after auth migration rollback")
	}
	if columnExists(t, db, "task_events", "actor_user_id") {
		t.Fatal("actor_user_id exists after auth migration rollback")
	}
	if !tableExists(t, db, "purchase_tasks") {
		t.Fatal("purchase_tasks was lost during auth migration rollback")
	}
	if applied, err := runner.Up(context.Background()); err != nil {
		t.Fatalf("Up(v3-v16) error = %v", err)
	} else if applied != 14 {
		t.Fatalf("Up(v3-v16) applied = %d, want 14", applied)
	}
}

func newRepositoryAuthService(
	t *testing.T,
	db *sql.DB,
) *usecase.AuthService {
	t.Helper()
	store, err := repository.New(db)
	if err != nil {
		t.Fatalf("repository.New() error = %v", err)
	}
	passwords, err := password.NewBcrypt(bcrypt.MinCost)
	if err != nil {
		t.Fatalf("password.NewBcrypt() error = %v", err)
	}
	service, err := usecase.NewAuthService(
		store,
		passwords,
		repositoryAuthClock{
			now: time.Date(2026, 7, 26, 12, 0, 0, 0, time.UTC),
		},
		&repositoryAuthIDGenerator{},
		&repositoryAuthTokenGenerator{},
	)
	if err != nil {
		t.Fatalf("usecase.NewAuthService() error = %v", err)
	}
	return service
}

func assertRepositoryAuthCode(t *testing.T, err error, code string) {
	t.Helper()
	var authError *usecase.Error
	if !errors.As(err, &authError) || authError.Code != code {
		t.Fatalf("error = %v, want code %s", err, code)
	}
}

func tableExists(
	t *testing.T,
	db *sql.DB,
	name string,
) bool {
	t.Helper()
	var count int
	if err := db.QueryRow(
		"SELECT COUNT(*) FROM sqlite_master WHERE type = 'table' AND name = ?",
		name,
	).Scan(&count); err != nil {
		t.Fatalf("query table %s: %v", name, err)
	}
	return count == 1
}

func columnExists(
	t *testing.T,
	db *sql.DB,
	table string,
	column string,
) bool {
	t.Helper()
	rows, err := db.Query("PRAGMA table_info(" + table + ")")
	if err != nil {
		t.Fatalf("PRAGMA table_info(%s): %v", table, err)
	}
	defer rows.Close()
	for rows.Next() {
		var cid int
		var name string
		var dataType string
		var notNull int
		var defaultValue any
		var primaryKey int
		if err := rows.Scan(
			&cid,
			&name,
			&dataType,
			&notNull,
			&defaultValue,
			&primaryKey,
		); err != nil {
			t.Fatalf("scan table_info(%s): %v", table, err)
		}
		if name == column {
			return true
		}
	}
	if err := rows.Err(); err != nil {
		t.Fatalf("iterate table_info(%s): %v", table, err)
	}
	return false
}

type repositoryAuthClock struct {
	now time.Time
}

func (clock repositoryAuthClock) Now() time.Time {
	return clock.now
}

type repositoryAuthIDGenerator struct {
	mu   sync.Mutex
	next int
}

func (generator *repositoryAuthIDGenerator) NewID() (string, error) {
	generator.mu.Lock()
	defer generator.mu.Unlock()
	generator.next++
	return uuid(600 + generator.next), nil
}

type repositoryAuthTokenGenerator struct {
	mu   sync.Mutex
	next byte
}

func (generator *repositoryAuthTokenGenerator) NewToken() (string, error) {
	generator.mu.Lock()
	defer generator.mu.Unlock()
	generator.next++
	value := make([]byte, 32)
	for index := range value {
		value[index] = generator.next + byte(index)
	}
	return base64.RawURLEncoding.EncodeToString(value), nil
}