/*
This is a post checking tool that performs role specific tests on the roles to ensure that everything
is installed and running correctly
*/

package postcheck

import (
	"errors"
	"flag"
	"fmt"
	log "github.com/Sirupsen/logrus"
	"github.com/jeffail/gabs"
	"golang.org/x/crypto/ssh"
	"gopkg.in/mgo.v2"
	"gopkg.in/mgo.v2/bson"
	"lib/check"
	"lib/sshutility"
	"strings"
	"time"
	"utils/helper"
)

var (
	hostIps      = ""
	username     = ""
	configJson   *gabs.Container
	password     = ""
	hostsToCheck []string
	postCheckErr = errors.New("Postcheck failed!")
)

type HostsMappingDoc struct {
	Cluster string
	Mapping map[string]interface{}
}

func init() {
	flag.StringVar(&hostIps, "mongo_hosts", "", "mongodb IP's")
	flag.StringVar(&username, "username", "", "mongodb username")
	flag.StringVar(&password, "password", "", "mongodb password")
}

// Method to check if the mongodb details are not empty
func checkInfo(hostIps string, username string, password string) error {
	if hostIps == "" || username == "" || password == "" {
		return errors.New("Please provide the mongodb IP/s, mongodb username and password")
	}
	return nil
}

func Exec(configJsonDeploy *gabs.Container) error {

	flag.Parse()

	// Check if the input config is used
	if configJsonDeploy != nil {
		// Collect mongodb information and retrieve the config form the database
		mongoUsername, _ := configJsonDeploy.Path("user_input.mongodb.username").Data().(string)
		mongoPassword, _ := configJsonDeploy.Path("user_input.mongodb.password").Data().(string)
		var mongoIps []string
		helper.ExtractStringArray(&mongoIps, configJsonDeploy, "user_input.mongodb.hosts")
		var IPstring string
		// Check if a replica set is used
		if len(mongoIps) == 3 {
			IPstring = mongoIps[0] + "," + mongoIps[1] + "," + mongoIps[2]
		} else {
			IPstring = mongoIps[0]
		}
		configJson = getConfigJsonFromDatabase(IPstring, mongoUsername, mongoPassword)

	} else {
		// Check if mongodb details are provided
		err := checkInfo(hostIps, username, password)
		if err != nil {
			log.Fatal(err)
		}
		// Get the config from the mongo database
		configJson = getConfigJsonFromDatabase(hostIps, username, password)
	}
	//fmt.Println(configJson)
	log.Info("Running checks...")

	// Get in the username and password for ssh
	sshUsername := check.GetUser(configJson)
	sshPassword, _ := configJson.Path("user_input.ssh.password").Data().(string)
	sshPem, okSshPem := configJson.Path("user_input.ssh.pem").Data().(string)
	sshPort := configJson.Path("user_input.ssh.port").Data()
	sshPortStr := fmt.Sprintf("%v", sshPort)
	sshConn := sshutility.SSHConnection{
		UserName:    sshUsername,
		PassWord:    sshPassword,
		PemFileName: sshPem,
		UsePem:      okSshPem,
		DefaultPort: sshPortStr,
	}

	hostTypes := []string{"arrow_cloud", "mongodb"}
	// Check if the arrowdb cluster is present
	arrow_dbCnts, err := configJson.Path("user_input.arrow_db").Children()
	if err == nil && arrow_dbCnts != nil {
		hostTypes = append(hostTypes, "arrow_db")
	}
	var component_ips map[string][]string = check.GetMap(configJson, hostTypes)
	var channelArray []<-chan string
	// Iterate over the go map collecting key's and value's to write the hosts to a file
	for prod_component, ips := range component_ips {

		for x := 0; x < len(ips); x++ {
			ip := ips[x]
			// Run the checkHost method in parallel
			result := connectHost2(sshConn, configJson, prod_component, ip)
			channelArray = append(channelArray, result)
		}
	}
	var passed = true

	fmt.Println(len(channelArray))
	for x := 0; x < len(channelArray); x++ {
		select {
		case chanResult := <-channelArray[x]:
			boolResult := strings.Split(chanResult, "--")
			result := boolResult[1]
			if result == "failed" {
				passed = false
			}
		}
	}

	fmt.Println("passed = ", passed)

	// Final check to see is the postcheck passed, otherwise return an error
	if passed == true {
		log.Info("Arrowcloud_postcheck complete")
		return nil
	} else {
		return postCheckErr
	}

}

// SSH and run the postCheck method on the current node
func connectHost2(sshConn sshutility.SSHConnection, configJson *gabs.Container, prod_component string, hostIP string) <-chan string {
	c := make(chan string)
	go connectHost(sshConn, configJson, c, prod_component, hostIP)
	return c

}

// SSH and run the postCheck method on the current node
func connectHost(sshConn sshutility.SSHConnection, configJson *gabs.Container, c chan string, prod_component string, hostIP string) {

	node := map[string]string{
		"host": hostIP,
	}

	// Point towards the client in the ssh library
	sshClient, err := sshConn.Connect(node)

	if err != nil {
		log.Fatalf("Error when connecting to node[%s(%s)]: %v", prod_component, hostIP, err)
	}
	defer sshClient.Close()
	passed := postCheck(sshClient, configJson, prod_component, hostIP)
	var name = prod_component + "." + hostIP
	var result = ""
	if passed == true {
		result = name + "--passed"
	} else {
		result = name + "--failed"
	}

	c <- result

}

// Method that runs role specific checks to ensure certain tasks/services are running
func postCheck(sshClient *ssh.Client, configJson *gabs.Container, prod_component string, hostIP string) bool {

	var passed = true

	// Split up the component names into cluster and role
	prodCompArray := strings.Split(prod_component, ".")
	product, componentName := prodCompArray[0], prodCompArray[1]

	// Get the arrowdb_url_prefix and domain_name form the user_input
	arrowdb_url_prefix, _ := configJson.Path("user_input.arrowdb_url_prefix").Data().(string)
	domain_name, _ := configJson.Path("user_input.domain_name").Data().(string)

	// Switch cases to distinguish between the roles
	switch product {
	case "arrow_cloud":
		switch componentName {
		case "stratus":

			curl := "curl " + hostIP + ":7000/ping.json"
			var expected = "\"ping\": \"ok\""
			passed = runCurl(sshClient, curl, product, componentName, hostIP, expected)

		case "log_aggregator":

		case "app_haproxy":

		case "admin_haproxy":

		case "admin":

		case "docker_registry":

		case "container_node":

			curlSession, _ := sshClient.NewSession()
			curl := "curl " + hostIP + ":9090/ping"
			if err := curlSession.Run(curl); err != nil {
				passed = false
				log.Error("cannot '"+curl+"' from <"+product+"."+componentName+">, IP : ", hostIP)
			}
			defer curlSession.Close()

		default:
			log.Error("the hosts are unreadable")
			return false
		}
	case "arrow_db":
		switch componentName {
		case "api":

			curlSession, _ := sshClient.NewSession()
			curl := "curl " + hostIP + ":8082"
			if err := curlSession.Run(curl); err != nil {
				passed = false
				log.Error("cannot '"+curl+"' from <"+product+"."+componentName+">, IP : ", hostIP)
			} else {
				defer curlSession.Close()
			}

		case "upload":

			delayed_jobSession, _ := sshClient.NewSession()
			output, _ := delayed_jobSession.Output("ps -ef")
			outputString := string(output[:])
			defer delayed_jobSession.Close()
			if !strings.Contains(outputString, "delayed_job") {
				log.Error("delayed_job is not running on " + hostIP + " \n")
				passed = false
			}

			curlSession, _ := sshClient.NewSession()
			curl := "curl " + hostIP + ":8082"
			if err := curlSession.Run(curl); err != nil {
				passed = false
				log.Error("cannot '"+curl+"' from <"+product+"."+componentName+">, IP : ", hostIP)
			} else {
				defer curlSession.Close()
			}

		case "admin":

		case "haproxy":

			curl := "curl --header \"Host: " + arrowdb_url_prefix + "." + domain_name + "\" " + hostIP + "/v1/admins/ping.json"
			var expected = "\"code\":200"
			passed = runCurl(sshClient, curl, product, componentName, hostIP, expected)

		case "push":

		default:
			log.Println("the hosts are unreadable")
			return false
		}
	}
	return passed
}

// Method to cmpare the output of the test with the expected result
func compareOutput(result string, curl string, product string, componentName string, hostIP string, expected string) bool {
	// Check if the output contains the result
	if !strings.Contains(result, expected) {
		return false
	}
	return true
}

// Method that ssh's into the host and runs a curl command
func runCurl(sshClient *ssh.Client, curl string, product string, componentName string, hostIP string, expected string) bool {
	result := ""
	// Check if the ssh.Client is not nil
	if sshClient != nil {
		curlSession, _ := sshClient.NewSession()
		out, _ := curlSession.Output(curl)
		result = string(out[:])
		// Make sure the output is not empty
		if result == "" {
			log.Error("cannot curl : " + curl)
		} else {
			defer curlSession.Close()
		}
	}

	// Compare the output with the expected result
	var output = compareOutput(result, curl, product, componentName, hostIP, expected)
	if output == false {
		log.Error("cannot '"+curl+"' from <"+product+"."+componentName+">, IP : ", hostIP)
		return false
	}
	return true
}

/**
If user specifies hosts array in user_input only (does not assign hosts to arrowcloud/DB roles) we should get
configuration from database which was saved when setting up the cluster.
*/
func getConfigJsonFromDatabase(hostIps string, dbUsername string, dbPassword string) *gabs.Container {

	mongoHosts := strings.Split(hostIps, ",")

	// Append the port to each IP
	var mongoHostPorts []string
	for x := 0; x < len(mongoHosts); x++ {
		mongoHostPorts = append(mongoHostPorts, mongoHosts[x]+":27017")
	}

	log.Infof("Retrieving configuration from database: %v", mongoHostPorts)

	// Initialize info using the username, password and Host
	mongoDBDialInfo := &mgo.DialInfo{
		Addrs:    mongoHostPorts,
		Timeout:  10 * time.Second,
		Database: "deployment_stacks",
		Username: dbUsername,
		Password: dbPassword,
	}

	// Dial into mongo db using the replica set
	session, err := mgo.DialWithInfo(mongoDBDialInfo)

	if err != nil {
		log.Fatalf("Failed to connect to mongo nodes: %s\n", err)
	}
	session.SetMode(mgo.Monotonic, true)

	// Select the host_mapping collection
	c := session.DB("deployment_stacks").C("hosts_mapping")

	result := HostsMappingDoc{}

	// Find the record
	err = c.Find(bson.M{}).One(&result)
	if err != nil {
		log.Fatalf("Failed to get configuration from database. %v", err)
	}

	// Create a json object for the host map
	configInMongo, err := gabs.Consume(result.Mapping)
	if err != nil {
		log.Fatalf("Failed to parsing configuration got from database. %v", err)
	}

	return configInMongo
}