package loadbalancer

import (
	"fmt"
	"time"

	"github.com/spf13/cobra"

	"github.com/hetznercloud/cli/internal/cmd/base"
	"github.com/hetznercloud/cli/internal/cmd/cmpl"
	"github.com/hetznercloud/cli/internal/hcapi2"
	"github.com/hetznercloud/cli/internal/state"
	"github.com/hetznercloud/hcloud-go/v2/hcloud"
)

var AddServiceCmd = base.Cmd{
	BaseCobraCommand: func(client hcapi2.Client) *cobra.Command {
		cmd := &cobra.Command{
			Use:                   "add-service [options] (--protocol http | --protocol tcp --listen-port <1-65535> --destination-port <1-65535> | --protocol https --http-certificates <ids>) <load-balancer>",
			Short:                 "Add a service to a Load Balancer",
			ValidArgsFunction:     cmpl.SuggestArgs(cmpl.SuggestCandidatesF(client.LoadBalancer().Names)),
			TraverseChildren:      true,
			DisableFlagsInUseLine: true,
		}
		cmd.Flags().String("protocol", "", "Protocol of the service (required)")
		_ = cmd.MarkFlagRequired("protocol")

		cmd.Flags().Int("listen-port", 0, "Listen port of the service")
		cmd.Flags().Int("destination-port", 0, "Destination port of the service on the targets")
		cmd.Flags().Bool("proxy-protocol", false, "Enable proxyprotocol (true, false)")

		cmd.Flags().Bool("http-sticky-sessions", false, "Enable Sticky Sessions (true, false)")
		cmd.Flags().String("http-cookie-name", "", "Sticky Sessions: Cookie Name we set")
		cmd.Flags().Duration("http-cookie-lifetime", 0, "Sticky Sessions: Lifetime of the cookie")
		cmd.Flags().StringSlice("http-certificates", []string{}, "IDs or names of Certificates which should be attached to this Load Balancer")
		cmd.Flags().Bool("http-redirect-http", false, "Redirect all traffic on port 80 to port 443 (true, false)")

		cmd.Flags().String("health-check-protocol", "", "The protocol the health check is performed over")
		cmd.Flags().Int("health-check-port", 0, "The port the health check is performed over")
		cmd.Flags().Duration("health-check-interval", 15*time.Second, "The interval the health check is performed")
		cmd.Flags().Duration("health-check-timeout", 10*time.Second, "The timeout after a health check is marked as failed")
		cmd.Flags().Int("health-check-retries", 3, "Number of retries after a health check is marked as failed")

		cmd.Flags().String("health-check-http-domain", "", "The domain we request when performing a http health check")
		cmd.Flags().String("health-check-http-path", "", "The path we request when performing a http health check")
		cmd.Flags().StringSlice("health-check-http-status-codes", []string{}, "List of status codes we expect to determine a target as healthy")
		cmd.Flags().String("health-check-http-response", "", "The response we expect to determine a target as healthy")
		cmd.Flags().Bool("health-check-http-tls", false, "Determine if the health check should verify if the target answers with a valid TLS certificate (true, false)")

		return cmd
	},
	Run: func(s state.State, cmd *cobra.Command, args []string) error {
		protocol, _ := cmd.Flags().GetString("protocol")
		listenPort, _ := cmd.Flags().GetInt("listen-port")
		destinationPort, _ := cmd.Flags().GetInt("destination-port")
		httpCertificates, _ := cmd.Flags().GetStringSlice("http-certificates")

		if protocol == "" {
			return fmt.Errorf("required flag protocol not set")
		}

		switch hcloud.LoadBalancerServiceProtocol(protocol) {
		case hcloud.LoadBalancerServiceProtocolHTTP:
			break
		case hcloud.LoadBalancerServiceProtocolTCP:
			if listenPort == 0 {
				return fmt.Errorf("please specify a listen port")
			}
			if destinationPort == 0 {
				return fmt.Errorf("please specify a destination port")
			}
		case hcloud.LoadBalancerServiceProtocolHTTPS:
			if len(httpCertificates) == 0 {
				return fmt.Errorf("no Certificate specified")
			}
		default:
			return fmt.Errorf("%s is not a valid protocol", protocol)
		}
		if listenPort > 65535 {
			return fmt.Errorf("%d is not a valid listen port", listenPort)
		}

		if destinationPort > 65535 {
			return fmt.Errorf("%d is not a valid destination port", destinationPort)
		}

		idOrName := args[0]

		proxyProtocol, _ := cmd.Flags().GetBool("proxy-protocol")
		httpStickySessions, _ := cmd.Flags().GetBool("http-sticky-sessions")
		httpCookieName, _ := cmd.Flags().GetString("http-cookie-name")
		httpCookieLifetime, _ := cmd.Flags().GetDuration("http-cookie-lifetime")
		httpRedirect, _ := cmd.Flags().GetBool("http-redirect-http")

		loadBalancer, _, err := s.Client().LoadBalancer().Get(s, idOrName)
		if err != nil {
			return err
		}
		if loadBalancer == nil {
			return fmt.Errorf("Load Balancer not found: %s", idOrName)
		}

		opts := hcloud.LoadBalancerAddServiceOpts{
			Protocol:      hcloud.LoadBalancerServiceProtocol(protocol),
			Proxyprotocol: &proxyProtocol,
		}

		if listenPort != 0 {
			opts.ListenPort = &listenPort
		}
		if destinationPort != 0 {
			opts.DestinationPort = &destinationPort
		}

		if protocol != string(hcloud.LoadBalancerServiceProtocolTCP) {
			opts.HTTP = &hcloud.LoadBalancerAddServiceOptsHTTP{
				StickySessions: &httpStickySessions,
				RedirectHTTP:   &httpRedirect,
			}
			if httpCookieName != "" {
				opts.HTTP.CookieName = &httpCookieName
			}
			if httpCookieLifetime != 0 {
				opts.HTTP.CookieLifetime = &httpCookieLifetime
			}
			for _, idOrName := range httpCertificates {
				cert, _, err := s.Client().Certificate().Get(s, idOrName)
				if err != nil {
					return err
				}
				opts.HTTP.Certificates = append(opts.HTTP.Certificates, cert)
			}
		}

		// Health check
		healthCheckProtocol, _ := cmd.Flags().GetString("health-check-protocol")
		healthCheckPort, _ := cmd.Flags().GetInt("health-check-port")
		healthCheckInterval, _ := cmd.Flags().GetDuration("health-check-interval")
		healthCheckTimeout, _ := cmd.Flags().GetDuration("health-check-timeout")
		healthCheckRetries, _ := cmd.Flags().GetInt("health-check-retries")

		addHealthCheck := false
		for _, f := range []string{"protocol", "port", "interval", "timeout", "retries"} {
			if cmd.Flags().Changed("health-check-" + f) {
				addHealthCheck = true
				break
			}
		}

		if addHealthCheck {
			opts.HealthCheck = &hcloud.LoadBalancerAddServiceOptsHealthCheck{}
			if healthCheckProtocol == "" {
				return fmt.Errorf("required flag health-check-protocol not set")
			}
			switch proto := hcloud.LoadBalancerServiceProtocol(healthCheckProtocol); proto {
			case hcloud.LoadBalancerServiceProtocolHTTP, hcloud.LoadBalancerServiceProtocolHTTPS, hcloud.LoadBalancerServiceProtocolTCP:
				opts.HealthCheck.Protocol = proto
			default:
				return fmt.Errorf("invalid health check protocol: %s", healthCheckProtocol)
			}

			if healthCheckPort == 0 {
				return fmt.Errorf("required flag health-check-port not set")
			}
			if healthCheckPort > 65535 {
				return fmt.Errorf("invalid health check port: %d", healthCheckPort)
			}
			opts.HealthCheck.Port = &healthCheckPort

			if cmd.Flags().Changed("health-check-interval") {
				opts.HealthCheck.Interval = &healthCheckInterval
			}
			if cmd.Flags().Changed("health-check-timeout") {
				opts.HealthCheck.Timeout = &healthCheckTimeout
			}
			if cmd.Flags().Changed("health-check-retries") {
				opts.HealthCheck.Retries = &healthCheckRetries
			}

			if opts.HealthCheck.Protocol == hcloud.LoadBalancerServiceProtocolHTTP ||
				opts.HealthCheck.Protocol == hcloud.LoadBalancerServiceProtocolHTTPS {

				opts.HealthCheck.HTTP = &hcloud.LoadBalancerAddServiceOptsHealthCheckHTTP{}
				healthCheckHTTPDomain, _ := cmd.Flags().GetString("health-check-http-domain")
				healthCheckHTTPPath, _ := cmd.Flags().GetString("health-check-http-path")
				healthCheckHTTPResponse, _ := cmd.Flags().GetString("health-check-http-response")
				healthCheckHTTPStatusCodes, _ := cmd.Flags().GetStringSlice("health-check-http-status-codes")
				healthCheckHTTPTLS, _ := cmd.Flags().GetBool("health-check-http-tls")

				if cmd.Flags().Changed("health-check-http-domain") {
					opts.HealthCheck.HTTP.Domain = &healthCheckHTTPDomain
				}
				if cmd.Flags().Changed("health-check-http-path") {
					opts.HealthCheck.HTTP.Path = &healthCheckHTTPPath
				}
				if cmd.Flags().Changed("health-check-http-response") {
					opts.HealthCheck.HTTP.Response = &healthCheckHTTPResponse
				}
				if cmd.Flags().Changed("health-check-http-status-codes") {
					opts.HealthCheck.HTTP.StatusCodes = healthCheckHTTPStatusCodes
				}
				if cmd.Flags().Changed("health-check-http-tls") {
					opts.HealthCheck.HTTP.TLS = &healthCheckHTTPTLS
				}
			}
		}

		action, _, err := s.Client().LoadBalancer().AddService(s, loadBalancer, opts)
		if err != nil {
			return err
		}
		if err := s.WaitForActions(s, cmd, action); err != nil {
			return err
		}
		cmd.Printf("Service was added to Load Balancer %d\n", loadBalancer.ID)

		return nil
	},
}
