/*
Real-time Online/Offline Charging System (OCS) for Telecom & ISP environments
Copyright (C) ITsysCOM GmbH

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>
*/

package services

import (
	"fmt"
	"os"
	"sync"

	"github.com/cgrates/birpc"
	v1 "github.com/cgrates/cgrates/apier/v1"
	"github.com/cgrates/cgrates/config"
	"github.com/cgrates/cgrates/cores"
	"github.com/cgrates/cgrates/engine"
	"github.com/cgrates/cgrates/utils"
)

// NewCoreService returns the Core Service
func NewCoreService(cfg *config.CGRConfig, caps *engine.Caps, server *cores.Server,
	internalCoreSChan chan birpc.ClientConnector, anz *AnalyzerService,
	fileCPU *os.File, shdWg *sync.WaitGroup, shdChan *utils.SyncedChan,
	srvDep map[string]*sync.WaitGroup) *CoreService {
	return &CoreService{
		shdChan:  shdChan,
		shdWg:    shdWg,
		connChan: internalCoreSChan,
		cfg:      cfg,
		caps:     caps,
		fileCPU:  fileCPU,
		server:   server,
		anz:      anz,
		srvDep:   srvDep,
	}
}

// CoreService implements Service interface
type CoreService struct {
	sync.RWMutex
	cfg      *config.CGRConfig
	server   *cores.Server
	caps     *engine.Caps
	stopChan chan struct{}
	shdWg    *sync.WaitGroup
	shdChan  *utils.SyncedChan
	fileCPU  *os.File
	cS       *cores.CoreService
	connChan chan birpc.ClientConnector
	anz      *AnalyzerService
	srvDep   map[string]*sync.WaitGroup
}

// Start should handle the service start
func (cS *CoreService) Start() error {
	if cS.IsRunning() {
		return utils.ErrServiceAlreadyRunning
	}

	cS.Lock()
	defer cS.Unlock()
	utils.Logger.Info(fmt.Sprintf("<%s> starting <%s> subsystem", utils.CoreS, utils.CoreS))
	cS.stopChan = make(chan struct{})
	cS.cS = cores.NewCoreService(cS.cfg, cS.caps, cS.fileCPU, cS.stopChan, cS.shdWg, cS.shdChan)
	srv, err := engine.NewService(v1.NewCoreSv1(cS.cS))
	if err != nil {
		return err
	}
	if !cS.cfg.DispatcherSCfg().Enabled {
		cS.server.RpcRegister(srv)
	}
	cS.connChan <- cS.anz.GetInternalCodec(srv, utils.CoreS)
	return nil
}

// Reload handles the change of config
func (cS *CoreService) Reload() (err error) {
	return
}

// Shutdown stops the service
func (cS *CoreService) Shutdown() (err error) {
	cS.Lock()
	defer cS.Unlock()
	cS.cS.Shutdown()
	close(cS.stopChan)
	cS.cS = nil
	<-cS.connChan
	return
}

// IsRunning returns if the service is running
func (cS *CoreService) IsRunning() bool {
	cS.RLock()
	defer cS.RUnlock()
	return cS.cS != nil
}

// ServiceName returns the service name
func (cS *CoreService) ServiceName() string {
	return utils.CoreS
}

// ShouldRun returns if the service should be running
func (cS *CoreService) ShouldRun() bool {
	return true
}

// GetCoreS returns the coreS
func (cS *CoreService) GetCoreS() *cores.CoreService {
	cS.RLock()
	defer cS.RUnlock()
	return cS.cS
}