package services

import (
	"context"
	"database/sql"
	"errors"

	"github.com/google/uuid"

	sqlerr "edge-infra.dev/pkg/edge/api/apierror/sql"
	"edge-infra.dev/pkg/edge/api/graph/model"
	sqlquery "edge-infra.dev/pkg/edge/api/sql"
	"edge-infra.dev/pkg/edge/api/utils"
)

//go:generate mockgen -destination=../mocks/mock_artifact_registry_service.go -package=mocks edge-infra.dev/pkg/edge/api/services ArtifactRegistryService
type ArtifactRegistryService interface {
	// Retrieve the artifact registry entry with a given ID.
	GetArtifactRegistry(ctx context.Context, registryEdgeID string) (*model.ArtifactRegistry, error)
	// Retrieve all artifact registries entries for a given banner.
	GetArtifactRegistriesForBanner(ctx context.Context, bannerEdgeID string) ([]*model.ArtifactRegistry, error)
	// Retrieve all artifact registries entries for a given cluster.
	GetArtifactRegistriesForCluster(ctx context.Context, clusterEdgeID string) ([]*model.ArtifactRegistry, error)
	// Create a new artifact registry entry.
	CreateArtifactRegistryEntry(ctx context.Context, createArtifactRegistry *model.ArtifactRegistryCreateInput) (*model.ArtifactRegistry, error)
	// Update the artifact registry entry with a given ID.
	UpdateArtifactRegistryEntry(ctx context.Context, registryEdgeID string, updateArtifactRegistry *model.ArtifactRegistryUpdateInput) (*model.ArtifactRegistry, error)
	// Delete the artifact registry entry with a given ID.
	DeleteArtifactRegistryEntry(ctx context.Context, registryEdgeID string) (bool, error)

	// Retrieve the cluster artifact registry entry with a given ID.
	GetClusterArtifactRegistry(ctx context.Context, clusterRegistryEdgeID string) (*model.ClusterArtifactRegistry, error)
	// Retrieve all cluster artifact registries for a given cluster.
	GetClusterArtifactRegistries(ctx context.Context, clusterEdgeID string) ([]*model.ClusterArtifactRegistry, error)
	// Create a new cluster artifact registry entry.
	CreateClusterArtifactRegistryEntry(ctx context.Context, createClusterArtifactRegistry *model.ClusterArtifactRegistryCreateInput) (*model.ClusterArtifactRegistry, error)
	// Delete the cluster artifact registry entry with a given ID.
	DeleteClusterArtifactRegistryEntry(ctx context.Context, clusterRegistryEdgeID string) (bool, error)
}

func NewArtifactRegistryService(sqlDB *sql.DB) ArtifactRegistryService {
	return &artifactRegistryService{
		SQLDB: sqlDB,
	}
}

type artifactRegistryService struct {
	SQLDB *sql.DB
}

func (s *artifactRegistryService) GetArtifactRegistry(ctx context.Context, registryEdgeID string) (*model.ArtifactRegistry, error) {
	row := s.SQLDB.QueryRowContext(ctx, sqlquery.GetArtifactRegistryByIDQuery, registryEdgeID)
	return s.scanArtifactRegistryRow(row)
}

func (s *artifactRegistryService) scanArtifactRegistryRow(row *sql.Row) (*model.ArtifactRegistry, error) {
	artifactRegistry := &model.ArtifactRegistry{}
	if err := row.Scan(&artifactRegistry.RegistryEdgeID, &artifactRegistry.BannerEdgeID, &artifactRegistry.Description, &artifactRegistry.URL); err != nil {
		return nil, err
	}
	return artifactRegistry, nil
}

func (s *artifactRegistryService) GetArtifactRegistriesForBanner(ctx context.Context, bannerEdgeID string) ([]*model.ArtifactRegistry, error) {
	rows, err := s.SQLDB.QueryContext(ctx, sqlquery.GetArtifactRegistriesForBannerQuery, bannerEdgeID)
	if err != nil {
		return nil, err
	}
	return s.scanArtifactRegistryRows(rows)
}

func (s *artifactRegistryService) GetArtifactRegistriesForCluster(ctx context.Context, clusterEdgeID string) ([]*model.ArtifactRegistry, error) {
	rows, err := s.SQLDB.QueryContext(ctx, sqlquery.GetArtifactRegistriesForClusterQuery, clusterEdgeID)
	if err != nil {
		return nil, err
	}
	return s.scanArtifactRegistryRows(rows)
}

func (s *artifactRegistryService) scanArtifactRegistryRows(rows *sql.Rows) ([]*model.ArtifactRegistry, error) {
	artifactRegistries := []*model.ArtifactRegistry{}

	for rows.Next() {
		artifactRegistry := &model.ArtifactRegistry{}
		if err := rows.Scan(&artifactRegistry.RegistryEdgeID, &artifactRegistry.BannerEdgeID, &artifactRegistry.Description, &artifactRegistry.URL); err != nil {
			return nil, err
		}
		artifactRegistries = append(artifactRegistries, artifactRegistry)
	}

	if err := rows.Err(); err != nil {
		return nil, sqlerr.Wrap(err)
	}

	return artifactRegistries, nil
}

func (s *artifactRegistryService) CreateArtifactRegistryEntry(ctx context.Context, createArtifactRegistry *model.ArtifactRegistryCreateInput) (artifactRegistry *model.ArtifactRegistry, err error) {
	if err := utils.ValidateArtifactRegistryCreateInput(createArtifactRegistry); err != nil {
		return nil, err
	}

	transaction, err := s.SQLDB.BeginTx(ctx, nil)
	if err != nil {
		return nil, err
	}

	defer func() {
		err = rollbackOnError(transaction, err)
	}()

	artifactRegistry = utils.CreateArtifactRegistryModel(
		uuid.NewString(),
		createArtifactRegistry.BannerEdgeID,
		createArtifactRegistry.URL,
		createArtifactRegistry.Description,
	)

	args := []any{
		artifactRegistry.RegistryEdgeID,
		artifactRegistry.BannerEdgeID,
		artifactRegistry.Description,
		artifactRegistry.URL,
	}

	if _, err = transaction.ExecContext(ctx, sqlquery.ArtifactRegistryCreateQuery, args...); err != nil {
		return
	}

	if err = transaction.Commit(); err != nil {
		return
	}

	return artifactRegistry, nil
}

func (s *artifactRegistryService) UpdateArtifactRegistryEntry(ctx context.Context, registryEdgeID string, updateArtifactRegistry *model.ArtifactRegistryUpdateInput) (artifactRegistry *model.ArtifactRegistry, err error) {
	if err := utils.ValidateArtifactRegistryUpdateInput(updateArtifactRegistry); err != nil {
		return nil, err
	}

	currentArtifactRegistry, err := s.GetArtifactRegistry(ctx, registryEdgeID)
	if err != nil {
		return nil, err
	}

	// return current if there are no changes to be made
	if !utils.ArtifactRegistryNeedsUpdating(currentArtifactRegistry, updateArtifactRegistry) {
		return currentArtifactRegistry, nil
	}

	transaction, err := s.SQLDB.BeginTx(ctx, nil)
	if err != nil {
		return nil, err
	}

	defer func() {
		err = rollbackOnError(transaction, err)
	}()

	artifactRegistry = utils.UpdateArtifactRegistry(currentArtifactRegistry, updateArtifactRegistry)

	args := []any{
		artifactRegistry.Description,
		artifactRegistry.URL,
		registryEdgeID,
	}

	if _, err = transaction.ExecContext(ctx, sqlquery.ArtifactRegistryUpdateQuery, args...); err != nil {
		return
	}

	if err = transaction.Commit(); err != nil {
		return
	}

	return artifactRegistry, nil
}

func (s *artifactRegistryService) DeleteArtifactRegistryEntry(ctx context.Context, registryEdgeID string) (bool, error) {
	// do nothing if entry does not exist
	if exists, err := s.artifactRegistryEntryExists(ctx, registryEdgeID); err != nil {
		return false, err
	} else if !exists {
		return false, nil
	}

	if _, err := s.SQLDB.ExecContext(ctx, sqlquery.ArtifactRegistryDeleteQuery, registryEdgeID); err != nil {
		return false, err
	}

	return true, nil
}

func (s *artifactRegistryService) artifactRegistryEntryExists(ctx context.Context, registryEdgeID string) (bool, error) {
	exists := false

	row := s.SQLDB.QueryRowContext(ctx, sqlquery.ArtifactRegistryExistsQuery, registryEdgeID)
	if err := row.Scan(&exists); err != nil {
		return false, err
	}

	return exists, nil
}

func (s *artifactRegistryService) GetClusterArtifactRegistry(ctx context.Context, clusterRegistryEdgeID string) (*model.ClusterArtifactRegistry, error) {
	row := s.SQLDB.QueryRowContext(ctx, sqlquery.GetClusterArtifactRegistryByIDQuery, clusterRegistryEdgeID)
	return s.scanClusterArtifactRegistryRow(row)
}

func (s *artifactRegistryService) scanClusterArtifactRegistryRow(row *sql.Row) (*model.ClusterArtifactRegistry, error) {
	clusterArtifactRegistry := &model.ClusterArtifactRegistry{}
	if err := row.Scan(&clusterArtifactRegistry.ClusterRegistryEdgeID, &clusterArtifactRegistry.ClusterEdgeID, &clusterArtifactRegistry.RegistryEdgeID); err != nil {
		return nil, err
	}
	return clusterArtifactRegistry, nil
}

func (s *artifactRegistryService) GetClusterArtifactRegistries(ctx context.Context, clusterEdgeID string) ([]*model.ClusterArtifactRegistry, error) {
	rows, err := s.SQLDB.QueryContext(ctx, sqlquery.GetClusterArtifactRegistriesForClusterQuery, clusterEdgeID)
	if err != nil {
		return nil, err
	}
	return s.scanClusterArtifactRegistryRows(rows)
}

func (s *artifactRegistryService) scanClusterArtifactRegistryRows(rows *sql.Rows) ([]*model.ClusterArtifactRegistry, error) {
	clusterArtifactRegistries := []*model.ClusterArtifactRegistry{}

	for rows.Next() {
		clusterArtifactRegistry := &model.ClusterArtifactRegistry{}
		if err := rows.Scan(&clusterArtifactRegistry.ClusterRegistryEdgeID, &clusterArtifactRegistry.ClusterEdgeID, &clusterArtifactRegistry.RegistryEdgeID); err != nil {
			return nil, err
		}
		clusterArtifactRegistries = append(clusterArtifactRegistries, clusterArtifactRegistry)
	}

	if err := rows.Err(); err != nil {
		return nil, sqlerr.Wrap(err)
	}

	return clusterArtifactRegistries, nil
}

func (s *artifactRegistryService) CreateClusterArtifactRegistryEntry(ctx context.Context, createClusterArtifactRegistry *model.ClusterArtifactRegistryCreateInput) (clusterArtifactRegistry *model.ClusterArtifactRegistry, err error) {
	transaction, err := s.SQLDB.BeginTx(ctx, nil)
	if err != nil {
		return nil, err
	}

	defer func() {
		err = rollbackOnError(transaction, err)
	}()

	clusterArtifactRegistry = utils.CreateClusterArtifactRegistryModel(
		uuid.NewString(),
		createClusterArtifactRegistry.ClusterEdgeID,
		createClusterArtifactRegistry.RegistryEdgeID,
	)

	args := []any{
		clusterArtifactRegistry.ClusterRegistryEdgeID,
		clusterArtifactRegistry.ClusterEdgeID,
		clusterArtifactRegistry.RegistryEdgeID,
	}

	if _, err = transaction.ExecContext(ctx, sqlquery.ClusterArtifactRegistryCreateQuery, args...); err != nil {
		return
	}

	if err = transaction.Commit(); err != nil {
		return
	}

	return clusterArtifactRegistry, nil
}

func (s *artifactRegistryService) DeleteClusterArtifactRegistryEntry(ctx context.Context, clusterRegistryEdgeID string) (bool, error) {
	// do nothing if entry does not exist
	if exists, err := s.clusterArtifactRegistryEntryExists(ctx, clusterRegistryEdgeID); err != nil {
		return false, err
	} else if !exists {
		return false, nil
	}

	if _, err := s.SQLDB.ExecContext(ctx, sqlquery.ClusterArtifactRegistryDeleteQuery, clusterRegistryEdgeID); err != nil {
		return false, err
	}

	return true, nil
}

func (s *artifactRegistryService) clusterArtifactRegistryEntryExists(ctx context.Context, clusterRegistryEdgeID string) (bool, error) {
	exists := false

	row := s.SQLDB.QueryRowContext(ctx, sqlquery.ClusterArtifactRegistryExistsQuery, clusterRegistryEdgeID)
	if err := row.Scan(&exists); err != nil {
		return false, err
	}

	return exists, nil
}

func rollbackOnError(transaction *sql.Tx, err error) error {
	if err != nil {
		return errors.Join(err, transaction.Rollback())
	}
	return nil
}