package commands

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"

	"github.com/spf13/cobra"

	"github.com/MichaelMure/git-bug/bridge"
	"github.com/MichaelMure/git-bug/bridge/core"
	"github.com/MichaelMure/git-bug/bridge/core/auth"
	"github.com/MichaelMure/git-bug/cache"
	"github.com/MichaelMure/git-bug/repository"
	"github.com/MichaelMure/git-bug/util/interrupt"
)

const (
	defaultName = "default"
)

var (
	bridgeConfigureName       string
	bridgeConfigureTarget     string
	bridgeConfigureParams     core.BridgeParams
	bridgeConfigureToken      string
	bridgeConfigureTokenStdin bool
)

func runBridgeConfigure(cmd *cobra.Command, args []string) error {
	backend, err := cache.NewRepoCache(repo)
	if err != nil {
		return err
	}
	defer backend.Close()
	interrupt.RegisterCleaner(backend.Close)

	if (bridgeConfigureTokenStdin || bridgeConfigureToken != "" || bridgeConfigureParams.CredPrefix != "") &&
		(bridgeConfigureName == "" || bridgeConfigureTarget == "") {
		return fmt.Errorf("you must provide a bridge name and target to configure a bridge with a credential")
	}

	// early fail
	if bridgeConfigureParams.CredPrefix != "" {
		if _, err := auth.LoadWithPrefix(repo, bridgeConfigureParams.CredPrefix); err != nil {
			return err
		}
	}

	switch {
	case bridgeConfigureTokenStdin:
		reader := bufio.NewReader(os.Stdin)
		token, err := reader.ReadString('\n')
		if err != nil {
			return fmt.Errorf("reading from stdin: %v", err)
		}
		bridgeConfigureParams.TokenRaw = strings.TrimSpace(token)
	case bridgeConfigureToken != "":
		bridgeConfigureParams.TokenRaw = bridgeConfigureToken
	}

	if bridgeConfigureTarget == "" {
		bridgeConfigureTarget, err = promptTarget()
		if err != nil {
			return err
		}
	}

	if bridgeConfigureName == "" {
		bridgeConfigureName, err = promptName(repo)
		if err != nil {
			return err
		}
	}

	b, err := bridge.NewBridge(backend, bridgeConfigureTarget, bridgeConfigureName)
	if err != nil {
		return err
	}

	err = b.Configure(bridgeConfigureParams)
	if err != nil {
		return err
	}

	fmt.Printf("Successfully configured bridge: %s\n", bridgeConfigureName)
	return nil
}

func promptTarget() (string, error) {
	targets := bridge.Targets()

	for {
		for i, target := range targets {
			fmt.Printf("[%d]: %s\n", i+1, target)
		}
		fmt.Printf("target: ")

		line, err := bufio.NewReader(os.Stdin).ReadString('\n')

		if err != nil {
			return "", err
		}

		line = strings.TrimSpace(line)

		index, err := strconv.Atoi(line)
		if err != nil || index <= 0 || index > len(targets) {
			fmt.Println("invalid input")
			continue
		}

		return targets[index-1], nil
	}
}

func promptName(repo repository.RepoConfig) (string, error) {
	defaultExist := core.BridgeExist(repo, defaultName)

	for {
		if defaultExist {
			fmt.Printf("name: ")
		} else {
			fmt.Printf("name [%s]: ", defaultName)
		}

		line, err := bufio.NewReader(os.Stdin).ReadString('\n')
		if err != nil {
			return "", err
		}

		line = strings.TrimSpace(line)

		name := line
		if defaultExist && name == "" {
			continue
		}

		if name == "" {
			name = defaultName
		}

		if !core.BridgeExist(repo, name) {
			return name, nil
		}

		fmt.Println("a bridge with the same name already exist")
	}
}

var bridgeConfigureCmd = &cobra.Command{
	Use:   "configure",
	Short: "Configure a new bridge.",
	Long: `	Configure a new bridge by passing flags or/and using interactive terminal prompts. You can avoid all the terminal prompts by passing all the necessary flags to configure your bridge.`,
	Example: `# Interactive example
[1]: github
[2]: gitlab
[3]: jira
[4]: launchpad-preview

target: 1
name [default]: default

Detected projects:
[1]: github.com/a-hilaly/git-bug
[2]: github.com/MichaelMure/git-bug

[0]: Another project

Select option: 1

[1]: user provided token
[2]: interactive token creation
Select option: 1

You can generate a new token by visiting https://github.com/settings/tokens.
Choose 'Generate new token' and set the necessary access scope for your repository.

The access scope depend on the type of repository.
Public:
	- 'public_repo': to be able to read public repositories
Private:
	- 'repo'       : to be able to read private repositories

Enter token: 87cf5c03b64029f18ea5f9ca5679daa08ccbd700
Successfully configured bridge: default

# For GitHub
git bug bridge configure \
    --name=default \
    --target=github \
    --owner=$(OWNER) \
    --project=$(PROJECT) \
    --token=$(TOKEN)

# For Launchpad
git bug bridge configure \
    --name=default \
    --target=launchpad-preview \
	--url=https://bugs.launchpad.net/ubuntu/

# For Gitlab
git bug bridge configure \
    --name=default \
    --target=github \
    --url=https://github.com/michaelmure/git-bug \
    --token=$(TOKEN)`,
	PreRunE: loadRepo,
	RunE:    runBridgeConfigure,
}

func init() {
	bridgeCmd.AddCommand(bridgeConfigureCmd)
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureName, "name", "n", "", "A distinctive name to identify the bridge")
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureTarget, "target", "t", "",
		fmt.Sprintf("The target of the bridge. Valid values are [%s]", strings.Join(bridge.Targets(), ",")))
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureParams.URL, "url", "u", "", "The URL of the remote repository")
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureParams.BaseURL, "base-url", "b", "", "The base URL of your remote issue tracker")
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureParams.Login, "login", "l", "", "The login on your remote issue tracker")
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureParams.CredPrefix, "credential", "c", "", "The identifier or prefix of an already known credential for your remote issue tracker (see \"git-bug bridge auth\")")
	bridgeConfigureCmd.Flags().StringVar(&bridgeConfigureToken, "token", "", "A raw authentication token for the remote issue tracker")
	bridgeConfigureCmd.Flags().BoolVar(&bridgeConfigureTokenStdin, "token-stdin", false, "Will read the token from stdin and ignore --token")
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureParams.Owner, "owner", "o", "", "The owner of the remote repository")
	bridgeConfigureCmd.Flags().StringVarP(&bridgeConfigureParams.Project, "project", "p", "", "The name of the remote repository")
	bridgeConfigureCmd.Flags().SortFlags = false
}