// Copyright (C) 2014-2018 Goodrain Co., Ltd.
// RAINBOND, Application Management Platform

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version. For any non-GPL usage of Rainbond,
// one or multiple Commercial Licenses authorized by Goodrain Co., Ltd.
// must be obtained first.

// 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 General Public License for more details.

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

package option

import (
	"fmt"
	"os"
	"time"

	"github.com/goodrain/rainbond/util"

	"github.com/Sirupsen/logrus"
	"github.com/spf13/pflag"
)

// GWServer contains Config and LogLevel
type GWServer struct {
	Config
	LogLevel string
	Debug    bool
}

// NewGWServer creates a new option.GWServer
func NewGWServer() *GWServer {
	return &GWServer{}
}

//Config contains all configuration
type Config struct {
	K8SConfPath  string
	EtcdEndpoint []string
	EtcdTimeout  int
	ListenPorts  ListenPorts
	//This number should be, at maximum, the number of CPU cores on your system.
	WorkerProcesses    int
	WorkerRlimitNofile int
	ErrorLog           string
	WorkerConnections  int
	//essential for linux, optmized to serve many clients with each thread
	EnableEpool       bool
	EnableMultiAccept bool
	KeepaliveTimeout  int
	KeepaliveRequests int
	NginxUser         string
	IP                string
	ResyncPeriod      time.Duration
	// health check
	HealthPath         string
	HealthCheckTimeout time.Duration

	EnableMetrics bool

	EnableRbdEndpoints bool
	RbdEndpointsKey    string // key of Rainbond endpoints in ETCD
	EnableKApiServer   bool
	KApiServerIP       string
	EnableLangGrMe     bool
	LangGrMeIP         string
	EnableMVNGrMe      bool
	MVNGrMeIP          string
	EnableGrMe         bool
	GrMeIP             string
	EnableRepoGrMe     bool
	RepoGrMeIP         string
	NodeName           string
	HostIP             string
	EnableInterface    []string
}

// ListenPorts describe the ports required to run the gateway controller
type ListenPorts struct {
	HTTP   int
	HTTPS  int
	Status int
	Health int
}

// AddFlags adds flags
func (g *GWServer) AddFlags(fs *pflag.FlagSet) {
	fs.StringVar(&g.LogLevel, "log-level", "debug", "the gateway log level")
	fs.StringVar(&g.K8SConfPath, "kube-conf", "/opt/rainbond/etc/kubernetes/kubecfg/admin.kubeconfig", "absolute path to the kubeconfig file")
	fs.IntVar(&g.ListenPorts.Status, "status-port", 18080, `Port to use for exposing NGINX status pages.`)
	fs.IntVar(&g.WorkerProcesses, "worker-processes", 0, "Default get current compute cpu core number.This number should be, at maximum, the number of CPU cores on your system.")
	fs.IntVar(&g.WorkerConnections, "worker-connections", 4000, "Determines how many clients will be served by each worker process.")
	fs.IntVar(&g.WorkerRlimitNofile, "worker-rlimit-nofile", 200000, "Number of file descriptors used for Nginx. This is set in the OS with 'ulimit -n 200000'")
	fs.BoolVar(&g.EnableEpool, "enable-epool", true, "essential for linux, optmized to serve many clients with each thread")
	fs.BoolVar(&g.EnableMultiAccept, "enable-multi-accept", true, "Accept as many connections as possible, after nginx gets notification about a new connection.")
	fs.StringVar(&g.ErrorLog, "error-log", "/dev/stderr crit", "only log critical errors")
	fs.StringVar(&g.NginxUser, "nginx-user", "root", "nginx user name")
	fs.IntVar(&g.KeepaliveRequests, "keepalive-requests", 10000, "Number of requests a client can make over the keep-alive connection. ")
	fs.IntVar(&g.KeepaliveTimeout, "keepalive-timeout", 30, "Timeout for keep-alive connections. Server will close connections after this time.")
	fs.StringVar(&g.IP, "ip", "0.0.0.0", "Node ip.") // TODO: more detail
	fs.DurationVar(&g.ResyncPeriod, "resync-period", 10*time.Second, "the default resync period for any handlers added via AddEventHandler and how frequently the listener wants a full resync from the shared informer")
	// etcd
	fs.StringSliceVar(&g.EtcdEndpoint, "etcd-endpoints", []string{"http://127.0.0.1:2379"}, "etcd cluster endpoints.")
	fs.IntVar(&g.EtcdTimeout, "etcd-timeout", 5, "etcd http timeout seconds")
	// health check
	fs.StringVar(&g.HealthPath, "health-path", "/healthz", "absolute path to the kubeconfig file")
	fs.DurationVar(&g.HealthCheckTimeout, "health-check-timeout", 10, `Time limit, in seconds, for a probe to health-check-path to succeed.`)
	fs.IntVar(&g.ListenPorts.Health, "healthz-port", 10254, `Port to use for the healthz endpoint.`)
	fs.BoolVar(&g.EnableMetrics, "enable-metrics", true, "Enables the collection of rbd-gateway metrics")
	// rainbond endpoints
	fs.BoolVar(&g.EnableRbdEndpoints, "enable-rbd-endpoints", true, "switch of Rainbond endpoints")
	fs.StringVar(&g.RbdEndpointsKey, "rbd-endpoints", "/rainbond/endpoint/", "key of Rainbond endpoints in ETCD")
	fs.BoolVar(&g.EnableKApiServer, "enable-kubeapi", false, "enable load balancing of kube-apiserver")
	fs.StringVar(&g.KApiServerIP, "kubeapi-ip", "0.0.0.0", "ip address bound by kube-apiserver")
	fs.BoolVar(&g.EnableLangGrMe, "enable-lang-grme", true, "enable load balancing of lang.goodrain.me")
	fs.StringVar(&g.LangGrMeIP, "lang-grme-ip", "0.0.0.0", "ip address bound by lang.goodrain.me")
	fs.BoolVar(&g.EnableMVNGrMe, "enable-mvn-grme", true, "enable load balancing of maven.goodrain.me")
	fs.StringVar(&g.MVNGrMeIP, "mvn-grme-ip", "0.0.0.0", "ip address bound by maven.goodrain.me")
	fs.BoolVar(&g.EnableGrMe, "enable-grme", true, "enable load balancing of goodrain.me")
	fs.StringVar(&g.GrMeIP, "grme-ip", "0.0.0.0", "ip address bound by goodrain.me")
	fs.BoolVar(&g.EnableRepoGrMe, "enable-repo-grme", true, "enable load balancing of repo.goodrain.me")
	fs.StringVar(&g.RepoGrMeIP, "repo-grme-ip", "0.0.0.0", "ip address bound by repo.goodrain.me")
	fs.StringVar(&g.NodeName, "node-name", "", "this gateway node host name")
	fs.StringVar(&g.HostIP, "node-ip", "", "this gateway node ip")
	fs.BoolVar(&g.Debug, "debug", false, "enable pprof debug")
	fs.StringArrayVar(&g.EnableInterface, "enable-interface", nil, "The network interface name that support listening and managing by gateway")
}

// SetLog sets log
func (g *GWServer) SetLog() {
	level, err := logrus.ParseLevel(g.LogLevel)
	if err != nil {
		fmt.Println("set log level error." + err.Error())
		return
	}
	logrus.SetLevel(level)
}

//CheckConfig check config
func (g *GWServer) CheckConfig() error {
	if g.K8SConfPath == "" {
		return fmt.Errorf("kube config file path can not be empty")
	}
	if exist, _ := util.FileExists(g.K8SConfPath); !exist {
		return fmt.Errorf("kube config file %s not exist", g.K8SConfPath)
	}
	if g.NodeName == "" {
		g.NodeName, _ = os.Hostname()
	}
	if g.HostIP == "" {
		ip, err := util.LocalIP()
		if err != nil {
			logrus.Errorf("get ip failed,details %s", err.Error())
			return fmt.Errorf("get host ip failure %s", err.Error())
		}
		g.HostIP = ip.String()
	}
	return nil
}