package projection

import (
	"context"
	"database/sql"
	"encoding/json"
	"slices"

	"github.com/muhlemmer/gu"

	"github.com/zitadel/zitadel/backend/v3/domain"
	"github.com/zitadel/zitadel/backend/v3/storage/database"
	v3_sql "github.com/zitadel/zitadel/backend/v3/storage/database/dialect/sql"
	"github.com/zitadel/zitadel/backend/v3/storage/database/repository"
	"github.com/zitadel/zitadel/internal/eventstore"
	"github.com/zitadel/zitadel/internal/eventstore/handler/v2"
	"github.com/zitadel/zitadel/internal/repository/idp"
	"github.com/zitadel/zitadel/internal/repository/instance"
	"github.com/zitadel/zitadel/internal/repository/org"
	"github.com/zitadel/zitadel/internal/zerrors"
)

func (p *relationalTablesProjection) reduceSAMLIDPAdded(event eventstore.Event) (*handler.Statement, error) {
	var orgId *string
	var idpEvent idp.SAMLIDPAddedEvent
	switch e := event.(type) {
	case *org.SAMLIDPAddedEvent:
		idpEvent = e.SAMLIDPAddedEvent
		orgId = &idpEvent.Aggregate().ResourceOwner
	case *instance.SAMLIDPAddedEvent:
		idpEvent = e.SAMLIDPAddedEvent
	default:
		return nil, zerrors.ThrowInvalidArgumentf(nil, "HANDL-Ys02m1", "reduce.wrong.event.type %v", []eventstore.EventType{org.SAMLIDPAddedEventType, instance.SAMLIDPAddedEventType})
	}

	saml := domain.SAML{
		Metadata:                      idpEvent.Metadata,
		Key:                           idpEvent.Key,
		Certificate:                   idpEvent.Certificate,
		Binding:                       idpEvent.Binding,
		WithSignedRequest:             idpEvent.WithSignedRequest,
		NameIDFormat:                  idpEvent.NameIDFormat,
		TransientMappingAttributeName: idpEvent.TransientMappingAttributeName,
		SignatureAlgorithm:            idpEvent.SignatureAlgorithm,
	}

	payloadJSON, err := json.Marshal(saml)
	if err != nil {
		return nil, err
	}

	return handler.NewStatement(event, func(ctx context.Context, ex handler.Executer, _ string) error {
		tx, ok := ex.(*sql.Tx)
		if !ok {
			return zerrors.ThrowInvalidArgumentf(nil, "HANDL-ksJ3N", "reduce.wrong.db.pool %T", ex)
		}

		repo := repository.IDProviderRepository()
		return repo.Create(ctx, v3_sql.SQLTx(tx), &domain.IdentityProvider{
			InstanceID:        idpEvent.Aggregate().InstanceID,
			OrgID:             orgId,
			ID:                idpEvent.ID,
			State:             domain.IDPStateActive,
			Name:              idpEvent.Name,
			Type:              gu.Ptr(domain.IDPTypeSAML),
			AllowCreation:     idpEvent.IsCreationAllowed,
			AllowAutoCreation: idpEvent.IsAutoCreation,
			AllowAutoUpdate:   idpEvent.IsAutoUpdate,
			AllowLinking:      idpEvent.IsLinkingAllowed,
			AutoLinkingField:  mapAutoLinkingField(idpEvent.AutoLinkingOption),
			Payload:           payloadJSON,
			CreatedAt:         event.CreatedAt(),
			UpdatedAt:         event.CreatedAt(),
		})
	}), nil
}

func (p *relationalTablesProjection) reduceSAMLIDPChanged(event eventstore.Event) (*handler.Statement, error) {
	var orgId *string
	var idpEvent idp.SAMLIDPChangedEvent
	switch e := event.(type) {
	case *org.SAMLIDPChangedEvent:
		idpEvent = e.SAMLIDPChangedEvent
		orgId = &idpEvent.Aggregate().ResourceOwner
	case *instance.SAMLIDPChangedEvent:
		idpEvent = e.SAMLIDPChangedEvent
	default:
		return nil, zerrors.ThrowInvalidArgumentf(nil, "HANDL-Y7c0fii4ad", "reduce.wrong.event.type %v", []eventstore.EventType{org.SAMLIDPChangedEventType, instance.SAMLIDPChangedEventType})
	}

	return handler.NewStatement(event, func(ctx context.Context, ex handler.Executer, _ string) error {
		tx, ok := ex.(*sql.Tx)
		if !ok {
			return zerrors.ThrowInternal(nil, "HANDL-HX6ed", "unable to cast to tx executer")
		}
		idpRepo := repository.IDProviderRepository()
		saml, err := idpRepo.GetSAML(ctx, v3_sql.SQLTx(tx), database.WithCondition(idpScopedCondition(idpRepo, idpEvent.Agg.InstanceID, idpEvent.ID, orgId)))
		if err != nil {
			return err
		}

		changes := p.reduceIDPChangedTemplateColumns(idpRepo, idpEvent.Name, idpEvent.OptionChanges)

		payload := &saml.SAML
		payloadChanged := p.reduceSAMLIDPChangedColumns(payload, &idpEvent)
		if payloadChanged {
			payloadJSON, err := json.Marshal(payload)
			if err != nil {
				return err
			}
			changes = append(changes, idpRepo.SetPayload(string(payloadJSON)))
		}

		changes = append(changes, idpRepo.SetUpdatedAt(gu.Ptr(event.CreatedAt())))
		_, err = idpRepo.Update(ctx, v3_sql.SQLTx(tx), idpScopedCondition(idpRepo, idpEvent.Aggregate().InstanceID, idpEvent.ID, orgId), changes...)
		return err

	}), nil
}

func (p *relationalTablesProjection) reduceSAMLIDPChangedColumns(payload *domain.SAML, idpEvent *idp.SAMLIDPChangedEvent) bool {
	payloadChanged := false
	if payload == nil || idpEvent == nil {
		return payloadChanged
	}

	if idpEvent.Metadata != nil && !slices.Equal(idpEvent.Metadata, payload.Metadata) {
		payloadChanged = true
		payload.Metadata = idpEvent.Metadata
	}
	if idpEvent.Key != nil {
		payloadChanged = true
		payload.Key = idpEvent.Key
	}
	if idpEvent.Certificate != nil && !slices.Equal(idpEvent.Certificate, payload.Certificate) {
		payloadChanged = true
		payload.Certificate = idpEvent.Certificate
	}
	if idpEvent.Binding != nil && *idpEvent.Binding != payload.Binding {
		payloadChanged = true
		payload.Binding = *idpEvent.Binding
	}
	if idpEvent.WithSignedRequest != nil && *idpEvent.WithSignedRequest != payload.WithSignedRequest {
		payloadChanged = true
		payload.WithSignedRequest = *idpEvent.WithSignedRequest
	}
	if idpEvent.NameIDFormat != nil && (payload.NameIDFormat == nil || *idpEvent.NameIDFormat != *payload.NameIDFormat) {
		payloadChanged = true
		payload.NameIDFormat = idpEvent.NameIDFormat
	}
	if idpEvent.TransientMappingAttributeName != nil && *idpEvent.TransientMappingAttributeName != payload.TransientMappingAttributeName {
		payloadChanged = true
		payload.TransientMappingAttributeName = *idpEvent.TransientMappingAttributeName
	}
	if idpEvent.FederatedLogoutEnabled != nil && *idpEvent.FederatedLogoutEnabled != payload.FederatedLogoutEnabled {
		payloadChanged = true
		payload.FederatedLogoutEnabled = *idpEvent.FederatedLogoutEnabled
	}
	if idpEvent.SignatureAlgorithm != nil && *idpEvent.SignatureAlgorithm != payload.SignatureAlgorithm {
		payloadChanged = true
		payload.SignatureAlgorithm = *idpEvent.SignatureAlgorithm
	}
	return payloadChanged
}