package main

import (
	"context"
	"fmt"
	"net/url"
	"os"
	"strings"

	"github.com/go-openapi/strfmt"
	"github.com/pkg/errors"
	log "github.com/sirupsen/logrus"
	"github.com/spf13/cobra"
	"gopkg.in/yaml.v2"

	"github.com/crowdsecurity/crowdsec/pkg/apiclient"
	"github.com/crowdsecurity/crowdsec/pkg/csconfig"
	"github.com/crowdsecurity/crowdsec/pkg/cwhub"
	"github.com/crowdsecurity/crowdsec/pkg/cwversion"
	"github.com/crowdsecurity/crowdsec/pkg/models"
)

var LAPIURLPrefix string = "v1"

func runLapiStatus (cmd *cobra.Command, args []string) error {
	var err error

	password := strfmt.Password(csConfig.API.Client.Credentials.Password)
	apiurl, err := url.Parse(csConfig.API.Client.Credentials.URL)
	login := csConfig.API.Client.Credentials.Login
	if err != nil {
		log.Fatalf("parsing api url ('%s'): %s", apiurl, err)
	}
	if err := csConfig.LoadHub(); err != nil {
		log.Fatal(err)
	}

	if err := cwhub.GetHubIdx(csConfig.Hub); err != nil {
		log.Info("Run 'sudo cscli hub update' to get the hub index")
		log.Fatalf("Failed to load hub index : %s", err)
	}
	scenarios, err := cwhub.GetInstalledScenariosAsString()
	if err != nil {
		log.Fatalf("failed to get scenarios : %s", err)
	}

	Client, err = apiclient.NewDefaultClient(apiurl,
		LAPIURLPrefix,
		fmt.Sprintf("crowdsec/%s", cwversion.VersionStr()),
		nil)
	if err != nil {
		log.Fatalf("init default client: %s", err)
	}
	t := models.WatcherAuthRequest{
		MachineID: &login,
		Password:  &password,
		Scenarios: scenarios,
	}
	log.Infof("Loaded credentials from %s", csConfig.API.Client.CredentialsFilePath)
	log.Infof("Trying to authenticate with username %s on %s", login, apiurl)
	_, err = Client.Auth.AuthenticateWatcher(context.Background(), t)
	if err != nil {
		log.Fatalf("Failed to authenticate to Local API (LAPI) : %s", err)
	} else {
		log.Infof("You can successfully interact with Local API (LAPI)")
	}

	return nil
}


func runLapiRegister(cmd *cobra.Command, args []string) error {
	var err error

	flags := cmd.Flags()

	apiURL, err := flags.GetString("url")
	if err != nil {
		return err
	}

	outputFile, err := flags.GetString("file")
	if err != nil {
		return err
	}

	lapiUser, err := flags.GetString("machine")
	if err != nil {
		return err
	}

	if lapiUser == "" {
		lapiUser, err = generateID("")
		if err != nil {
			log.Fatalf("unable to generate machine id: %s", err)
		}
	}
	password := strfmt.Password(generatePassword(passwordLength))
	if apiURL == "" {
		if csConfig.API.Client != nil && csConfig.API.Client.Credentials != nil && csConfig.API.Client.Credentials.URL != "" {
			apiURL = csConfig.API.Client.Credentials.URL
		} else {
			log.Fatalf("No Local API URL. Please provide it in your configuration or with the -u parameter")
		}
	}
	/*URL needs to end with /, but user doesn't care*/
	if !strings.HasSuffix(apiURL, "/") {
		apiURL += "/"
	}
	/*URL needs to start with http://, but user doesn't care*/
	if !strings.HasPrefix(apiURL, "http://") && !strings.HasPrefix(apiURL, "https://") {
		apiURL = "http://" + apiURL
	}
	apiurl, err := url.Parse(apiURL)
	if err != nil {
		log.Fatalf("parsing api url: %s", err)
	}
	_, err = apiclient.RegisterClient(&apiclient.Config{
		MachineID:     lapiUser,
		Password:      password,
		UserAgent:     fmt.Sprintf("crowdsec/%s", cwversion.VersionStr()),
		URL:           apiurl,
		VersionPrefix: LAPIURLPrefix,
	}, nil)

	if err != nil {
		log.Fatalf("api client register: %s", err)
	}

	log.Printf("Successfully registered to Local API (LAPI)")

	var dumpFile string
	if outputFile != "" {
		dumpFile = outputFile
	} else if csConfig.API.Client.CredentialsFilePath != "" {
		dumpFile = csConfig.API.Client.CredentialsFilePath
	} else {
		dumpFile = ""
	}
	apiCfg := csconfig.ApiCredentialsCfg{
		Login:    lapiUser,
		Password: password.String(),
		URL:      apiURL,
	}
	apiConfigDump, err := yaml.Marshal(apiCfg)
	if err != nil {
		log.Fatalf("unable to marshal api credentials: %s", err)
	}
	if dumpFile != "" {
		err = os.WriteFile(dumpFile, apiConfigDump, 0644)
		if err != nil {
			log.Fatalf("write api credentials in '%s' failed: %s", dumpFile, err)
		}
		log.Printf("Local API credentials dumped to '%s'", dumpFile)
	} else {
		fmt.Printf("%s\n", string(apiConfigDump))
	}
	log.Warning(ReloadMessage())

	return nil
}


func NewLapiStatusCmd() *cobra.Command {
	cmdLapiStatus := &cobra.Command{
		Use:               "status",
		Short:             "Check authentication to Local API (LAPI)",
		Args:              cobra.MinimumNArgs(0),
		DisableAutoGenTag: true,
		RunE:              runLapiStatus,
	}

	return cmdLapiStatus
}


func NewLapiRegisterCmd() *cobra.Command {
	cmdLapiRegister := &cobra.Command{
		Use:   "register",
		Short: "Register a machine to Local API (LAPI)",
		Long: `Register you machine to the Local API (LAPI).
Keep in mind the machine needs to be validated by an administrator on LAPI side to be effective.`,
		Args:              cobra.MinimumNArgs(0),
		DisableAutoGenTag: true,
		RunE: runLapiRegister,
	}

	flags := cmdLapiRegister.Flags()
	flags.StringP("url", "u", "", "URL of the API (ie. http://127.0.0.1)")
	flags.StringP("file", "f", "", "output file destination")
	flags.String("machine", "", "Name of the machine to register with")

	return cmdLapiRegister
}


func NewLapiCmd() *cobra.Command {
	var cmdLapi = &cobra.Command{
		Use:               "lapi [action]",
		Short:             "Manage interaction with Local API (LAPI)",
		Args:              cobra.MinimumNArgs(1),
		DisableAutoGenTag: true,
		PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
			if err := csConfig.LoadAPIClient(); err != nil {
				return errors.Wrap(err, "loading api client")
			}
			return nil
		},
	}

	cmdLapi.AddCommand(NewLapiRegisterCmd())
	cmdLapi.AddCommand(NewLapiStatusCmd())

	return cmdLapi
}