package main

import (
	"context"
	"fmt"
	"log"
	"os"
	"time"

	"github.com/docker/docker/api/types/container"
	"github.com/docker/docker/api/types/mount"
	"github.com/docker/docker/api/types/network"
	"github.com/docker/docker/client"
)

const (
	fixedDockerVersion = "1.38"
)

var (
	dockerCtx context.Context
	dockerCLI *client.Client
)

func setupContext() {
	if dockerCtx == nil {
		dockerCtx = context.Background()
	}
}

func setupDockerCLI() (err error) {
	os.Setenv("DOCKER_API_VERSION", "1.27")
	if dockerCLI == nil {
		dockerCLI, err = client.NewEnvClient()
	}
	return err
}

func spawnCompanion(username string, accesscode string) {
	log.Println("Spwaning a new companion container")
	// setup the context and the docker cli connection
	setupContext()
	setupDockerCLI()

	sessionSalt := generateSessionSalt()
	vpnRemoteAddress := "127.0.0.1"
	vpnRemotePort := "1193"

	log.Println("Generating the container config")

	Config := &container.Config{
		Image: "circus-companion:latest",
		Cmd:   []string{fmt.Sprintf("-username %s -accesscode %s -sessionSalt %s -vpnRemoteAddress %s -vpnRemotePort %s", username, accesscode, sessionSalt, vpnRemoteAddress, vpnRemotePort)},
		// Container labels used by traefik
		Labels: map[string]string{
			"traefik.enable": "true",
			"traefik.http.routers.companion.entrypoints":               "web",
			"traefik.http.routers.companion.rule":                      "Host(`companion.docker.localhost`)",
			"traefik.http.services.companion.loadbalancer.server.port": "8080",
		},
	}

	HostConfig := &container.HostConfig{
		Mounts: []mount.Mount{
			{
				Type:   mount.TypeBind,
				Source: "/var/run/docker.sock",
				Target: "/var/run/docker.sock",
			},
			{
				Type:   mount.TypeBind,
				Source: "/etc/companion.json",
				Target: "/etc/companion.json",
			},
		},
	}

	containerNetworkID, err := setupNetwork("circus", true)

	NetworkingConfig := &network.NetworkingConfig{
		EndpointsConfig: map[string]*network.EndpointSettings{
			"circus": {
				NetworkID: containerNetworkID,
			},
		},
	}

	log.Println("Starting the container")

	_, err := dockerCLI.ContainerCreate(dockerCtx, Config, HostConfig, NetworkingConfig, "")
	if err != nil {
		panic(err)
	}

	log.Println("Container started")
}

func generateSessionSalt() string {
	return fmt.Sprintf("%d", time.Now().UnixNano())
}