// Copyright 2018-2024 CERN
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// In applying this license, CERN does not waive the privileges and immunities
// granted to it by virtue of its status as an Intergovernmental Organization
// or submit itself to any jurisdiction.

package memory

import (
	"fmt"
	"sync"

	"github.com/cs3org/reva/v3/pkg/registry"
)

// Registry implements the Registry interface.
type Registry struct {
	// m protects async access to the services map.
	sync.Mutex
	// services map a service name with a set of nodes.
	services map[string]registry.Service
}

// Add implements the Registry interface. If the service is already known in this registry it will only update the nodes.
func (r *Registry) Add(svc registry.Service) error {
	r.Lock()
	defer r.Unlock()

	// append the nodes if the service is already registered.
	if _, ok := r.services[svc.Name()]; ok {
		s := service{
			name:  svc.Name(),
			nodes: make([]node, 0),
		}

		s.mergeNodes(svc.Nodes(), r.services[svc.Name()].Nodes())

		r.services[svc.Name()] = s
		return nil
	}

	r.services[svc.Name()] = svc
	return nil
}

// GetService implements the Registry interface. There is currently no load balance being done, but it should not be
// hard to add.
func (r *Registry) GetService(name string) (registry.Service, error) {
	r.Lock()
	defer r.Unlock()

	if service, ok := r.services[name]; ok {
		return service, nil
	}

	return nil, fmt.Errorf("service %v not found", name)
}

// New returns an implementation of the Registry interface.
func New(m map[string]any) registry.Registry {
	// c, err := registry.ParseConfig(m)
	// if err != nil {
	//	return nil
	// }

	return &Registry{
		services: map[string]registry.Service{},
	}
}
