// Copyright (c) 2023 Gitpod GmbH. All rights reserved.
// Licensed under the GNU Affero General Public License (AGPL).
// See License.AGPL.txt in the project root for license information.

package cmd

import (
	"context"
	"errors"
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"os"
	"time"

	"github.com/gitpod-io/gitpod/components/public-api/go/client"
	"github.com/gitpod-io/local-app/pkg/auth"
	"github.com/gitpod-io/local-app/pkg/config"
	"github.com/gitpod-io/local-app/pkg/constants"
	"github.com/gitpod-io/local-app/pkg/prettyprint"
	"github.com/gitpod-io/local-app/pkg/selfupdate"
	"github.com/gitpod-io/local-app/pkg/telemetry"
	"github.com/gookit/color"
	"github.com/lmittmann/tint"
	"github.com/mattn/go-isatty"
	"github.com/spf13/cobra"
)

var rootOpts struct {
	ConfigLocation string
	Verbose        bool
}

var rootCmd = &cobra.Command{
	Use:   "gitpod",
	Short: "Gitpod: Always ready to code.",
	Long: color.Sprint(`
<fg=ff971d>      .-+*#+           </>      <b>Gitpod: Always ready to code.</>
<fg=ff971d>   :=*#####*.          </>      Try the following commands to get started:
<fg=ff971d>  .=*####*+-.    .--:  </>
<fg=ff971d>  +****=:     :=*####+ </>      gitpod login              <lightgray>Login to Gitpod</>
<fg=ff971d>  ****:   .-+*########.</>      gitpod whoami             <lightgray>Show information about the currently logged in user</>
<fg=ff971d>  +***:   *****+--####.</>
<fg=ff971d>  +***:   .-=:.  .#*##.</>      gitpod workspace list     <lightgray>List your workspaces</>
<fg=ff971d>  +***+-.      .-+**** </>      gitpod workspace create   <lightgray>Create a new workspace</>
<fg=ff971d>  .=*****+=::-+*****+: </>      gitpod workspace open     <lightgray>Open a running workspace</>
<fg=ff971d>  .:=+*********=-.     </>      gitpod workspace stop     <lightgray>Stop a running workspace</>
<fg=ff971d>      .-++++=:         </>

	`),
	SilenceErrors: true,
	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
		level := slog.LevelInfo
		if rootOpts.Verbose {
			level = slog.LevelDebug
		}
		var noColor bool
		if !isatty.IsTerminal(os.Stdout.Fd()) {
			noColor = true
			color.Disable()
		}
		slog.SetDefault(slog.New(tint.NewHandler(os.Stdout, &tint.Options{
			Level:      level,
			NoColor:    noColor,
			TimeFormat: time.StampMilli,
			ReplaceAttr: func(groups []string, attr slog.Attr) slog.Attr {
				if attr.Key != "level" {
					return attr
				}

				switch attr.Value.String() {
				case slog.LevelDebug.String():
					attr.Value = slog.StringValue(color.Gray.Render("[DEBUG]"))
				case slog.LevelInfo.String():
					attr.Value = slog.StringValue(color.Green.Render("[INFO ]"))
				case slog.LevelWarn.String():
					attr.Value = slog.StringValue(color.Yellow.Render("[WARN ]"))
				case slog.LevelError.String():
					attr.Value = slog.StringValue(color.Red.Render("[ERROR]"))
				}
				return attr
			},
		})))

		cfg, err := config.LoadConfig(rootOpts.ConfigLocation)
		if errors.Is(err, os.ErrNotExist) {
			err = nil
		}
		if err != nil {
			return err
		}
		cmd.SetContext(config.ToContext(context.Background(), cfg))

		host := "https://gitpod.io"
		telemetryEnabled := !telemetry.DoNotTrack()
		telemetryEnabled = telemetryEnabled && cfg.Telemetry.Enabled
		gpctx, err := cfg.GetActiveContext()
		if err == nil && gpctx != nil {
			host = gpctx.Host.String()
		}
		telemetry.Init(telemetryEnabled, cfg.Telemetry.Identity, constants.Version.String(), level, host)
		telemetry.RecordCommand(cmd)

		if !isVersionCommand(cmd) {
			waitForUpdate := selfupdate.Autoupdate(cmd.Context(), cfg)
			cmd.PostRunE = func(cmd *cobra.Command, args []string) error {
				waitForUpdate()
				return nil
			}
		}

		return nil
	},
}

func Execute() {
	err := rootCmd.Execute()

	var exitCode int
	if err != nil {
		exitCode = 1
		prettyprint.PrintError(os.Stderr, os.Args[0], err)

		telemetry.RecordError(err)
	}

	telemetry.Close()
	os.Exit(exitCode)
}

func init() {
	if !isatty.IsTerminal(os.Stdout.Fd()) || !isatty.IsTerminal(os.Stderr.Fd()) {
		color.Disable()
	}

	configLocation := config.DEFAULT_LOCATION
	if fn := os.Getenv("GITPOD_CONFIG"); fn != "" {
		configLocation = fn
	}
	rootCmd.PersistentFlags().StringVar(&rootOpts.ConfigLocation, "config", configLocation, "Location of the configuration file")
	rootCmd.PersistentFlags().BoolVarP(&rootOpts.Verbose, "verbose", "v", false, "Display verbose output for more detailed logging")
}

var rootTestingOpts struct {
	Client    *client.Gitpod
	WriterOut io.Writer
}

var clientCache *client.Gitpod

func getGitpodClient(ctx context.Context) (*client.Gitpod, error) {
	// There will be only one client in a command context right now
	if clientCache != nil {
		return clientCache, nil
	}
	cfg := config.FromContext(ctx)
	gpctx, err := cfg.GetActiveContext()
	if err != nil {
		return nil, err
	}

	host := gpctx.Host
	if host == nil {
		return nil, prettyprint.AddResolution(fmt.Errorf("active context has no host configured"),
			"set a host using `gitpod config set-context --current --host <host>`",
			"login again using `gitpod login`",
			"change to a different context using `gitpod config use-context <context>`",
		)
	}

	if rootTestingOpts.Client != nil {
		return rootTestingOpts.Client, nil
	}

	token := gpctx.Token
	if token == "" {
		token = os.Getenv("GITPOD_TOKEN")
	}
	if token == "" {
		var err error
		token, err = auth.GetToken(host.String())
		if err != nil {
			return nil, err
		}
	}
	if token == "" {
		return nil, prettyprint.AddResolution(fmt.Errorf("no token found for active context"),
			"provide a token by setting the GITPOD_TOKEN environment variable",
			"login again using `gitpod login`",
			"change to a different context using `gitpod config use-context <context>`",
			"set a token explicitly using `gitpod config set-context --current --token <token>`",
		)
	}

	var apiHost = *gpctx.Host.URL
	apiHost.Host = "api." + apiHost.Host
	slog.Debug("establishing connection to Gitpod", "host", apiHost.String())
	res, err := client.New(
		client.WithCredentials(token),
		client.WithURL(apiHost.String()),
		client.WithHTTPClient(&http.Client{
			Transport: &auth.AuthenticatedTransport{Token: token, T: http.DefaultTransport},
		}),
	)
	if err != nil {
		return nil, err
	}
	clientCache = res

	return res, nil
}

type formatOpts struct {
	Field string
}

// WriteTabular writes the given tabular data to the writer
func WriteTabular[T any](v []T, opts formatOpts, format prettyprint.WriterFormat) error {
	var out io.Writer = os.Stdout
	if rootTestingOpts.WriterOut != nil {
		out = rootTestingOpts.WriterOut
	}
	w := &prettyprint.Writer[T]{
		Field:  opts.Field,
		Format: format,
		Out:    out,
	}
	return w.Write(v)
}

func addFormatFlags(cmd *cobra.Command, opts *formatOpts) {
	cmd.Flags().StringVarP(&opts.Field, "field", "f", "", "Only print the specified field")
}