package main

import (
	"encoding/json"
	"fmt"
	"regexp"
	"strings"

	"github.com/fatih/color"
	"github.com/minio/cli"
	"github.com/minio/mc/pkg/console"
	"github.com/minio/minio-xl/pkg/probe"
	"github.com/minio/minio-xl/pkg/quick"
)

var configHostCmd = cli.Command{
	Name:   "host",
	Usage:  "List, modify and remove hosts in configuration file.",
	Action: mainConfigHost,
	CustomHelpTemplate: `NAME:
   mc config {{.Name}} - {{.Usage}}

USAGE:
   mc config {{.Name}} OPERATION [ARGS...]

   OPERATION = add | list | remove

EXAMPLES:
   1. Add host configuration for a URL, using default signature V4. For security reasons turn off bash history
      $ set +o history
      $ mc config {{.Name}} add s3.amazonaws.com BKIKJAA5BMMU2RHO6IBB V7f1CwQqAcwo80UEIJEjc5gVQUSSx5ohQ9GSrr12
      $ set -o history

   2. Add host configuration for a URL, using s3 api v2. For security reasons turn off bash history
      $ set +o history
      $ mc config {{.Name}} add s3.amazonaws.com BKIKJAA5BMMU2RHO6IBB V7f1CwQqAcwo80UEIJEjc5gVQUSSx5ohQ9GSrr12 S3v2
      $ set -o history

   3. List all hosts.
      $ mc config {{.Name}} list

   4. Remove host config.
      $ mc config {{.Name}} remove s3.amazonaws.com

`,
}

// HostMessage container for content message structure
type HostMessage struct {
	op              string
	Host            string `json:"host"`
	AccessKeyID     string `json:"accessKeyId,omitempty"`
	SecretAccessKey string `json:"secretAccessKey,omitempty"`
	API             string `json:"api,omitempty"`
}

// String colorized host message
func (a HostMessage) String() string {
	if a.op == "list" {
		message := console.Colorize("Host", fmt.Sprintf("[%s] ", a.Host))
		if a.AccessKeyID != "" || a.SecretAccessKey != "" {
			message += console.Colorize("AccessKeyID", fmt.Sprintf("<- %s,", a.AccessKeyID))
			message += console.Colorize("SecretAccessKey", fmt.Sprintf(" %s,", a.SecretAccessKey))
			message += console.Colorize("API", fmt.Sprintf(" %s", a.API))
		}
		return message
	}
	if a.op == "remove" {
		return console.Colorize("HostMessage", "Removed host ‘"+a.Host+"’ successfully.")
	}
	if a.op == "add" {
		return console.Colorize("HostMessage", "Added host ‘"+a.Host+"’ successfully.")
	}
	// should never reach here
	return ""
}

// JSON jsonified host message
func (a HostMessage) JSON() string {
	jsonMessageBytes, e := json.Marshal(a)
	fatalIf(probe.NewError(e), "Unable to marshal into JSON.")

	return string(jsonMessageBytes)
}

func checkConfigHostSyntax(ctx *cli.Context) {
	// show help if nothing is set
	if !ctx.Args().Present() || ctx.Args().First() == "help" {
		cli.ShowCommandHelpAndExit(ctx, "host", 1) // last argument is exit code
	}
	if strings.TrimSpace(ctx.Args().First()) == "" {
		cli.ShowCommandHelpAndExit(ctx, "host", 1) // last argument is exit code
	}
	if len(ctx.Args().Tail()) > 4 {
		fatalIf(errDummy().Trace(), "Incorrect number of arguments to host command")
	}
	switch strings.TrimSpace(ctx.Args().First()) {
	case "add":
		if len(ctx.Args().Tail()) < 3 || len(ctx.Args().Tail()) > 4 {
			fatalIf(errInvalidArgument().Trace(), "Incorrect number of arguments for add host command.")
		}
	case "remove":
		if len(ctx.Args().Tail()) != 1 {
			fatalIf(errInvalidArgument().Trace(), "Incorrect number of arguments for remove host command.")
		}
	case "list":
	default:
		cli.ShowCommandHelpAndExit(ctx, "host", 1) // last argument is exit code
	}
}

func setConfigHostPalette(style string) {
	console.SetCustomPalette(map[string]*color.Color{
		"Host":            color.New(color.FgCyan, color.Bold),
		"API":             color.New(color.FgYellow, color.Bold),
		"HostMessage":     color.New(color.FgGreen, color.Bold),
		"AccessKeyID":     color.New(color.FgBlue, color.Bold),
		"SecretAccessKey": color.New(color.FgRed, color.Bold),
	})
	if style == "light" {
		console.SetCustomPalette(map[string]*color.Color{
			"Host":            color.New(color.FgWhite, color.Bold),
			"API":             color.New(color.FgWhite, color.Bold),
			"HostMessage":     color.New(color.FgWhite, color.Bold),
			"AccessKeyID":     color.New(color.FgWhite, color.Bold),
			"SecretAccessKey": color.New(color.FgWhite, color.Bold),
		})
		return
	}
	/// Add more styles here
	if style == "nocolor" {
		// All coloring options exhausted, setting nocolor safely
		console.SetNoColor()
	}
}

func mainConfigHost(ctx *cli.Context) {
	checkConfigHostSyntax(ctx)

	setConfigHostPalette(ctx.GlobalString("colors"))

	arg := ctx.Args().First()
	tailArgs := ctx.Args().Tail()

	switch strings.TrimSpace(arg) {
	case "add":
		addHost(tailArgs.Get(0), tailArgs.Get(1), tailArgs.Get(2), tailArgs.Get(3))
	case "remove":
		removeHost(tailArgs.Get(0))
	case "list":
		listHosts()
	}
}

func listHosts() {
	config, err := newConfig()
	fatalIf(err.Trace(), "Failed to initialize ‘quick’ configuration data structure.")

	configPath := mustGetMcConfigPath()
	err = config.Load(configPath)
	fatalIf(err.Trace(configPath), "Unable to load config path")

	// convert interface{} back to its original struct
	newConf := config.Data().(*configV5)
	for k, v := range newConf.Hosts {
		Prints("%s\n", HostMessage{
			op:              "list",
			Host:            k,
			AccessKeyID:     v.AccessKeyID,
			SecretAccessKey: v.SecretAccessKey,
			API:             v.API,
		})
	}

}

func removeHost(hostGlob string) {
	if strings.TrimSpace(hostGlob) == "" {
		fatalIf(errDummy().Trace(), "Alias or URL cannot be empty.")
	}
	if strings.TrimSpace(hostGlob) == "dl.minio.io:9000" {
		fatalIf(errDummy().Trace(), "‘"+hostGlob+"’ is reserved hostname and cannot be removed.")
	}
	config, err := newConfig()
	fatalIf(err.Trace(globalMCConfigVersion), "Failed to initialize ‘quick’ configuration data structure.")

	configPath := mustGetMcConfigPath()
	err = config.Load(configPath)
	fatalIf(err.Trace(configPath), "Unable to load config path")

	// convert interface{} back to its original struct
	newConf := config.Data().(*configV5)
	if _, ok := newConf.Hosts[hostGlob]; !ok {
		fatalIf(errDummy().Trace(), fmt.Sprintf("Host glob ‘%s’ does not exist.", hostGlob))
	}
	delete(newConf.Hosts, hostGlob)

	newConfig, err := quick.New(newConf)
	fatalIf(err.Trace(globalMCConfigVersion), "Failed to initialize ‘quick’ configuration data structure.")
	err = writeConfig(newConfig)
	fatalIf(err.Trace(hostGlob), "Unable to save host glob ‘"+hostGlob+"’.")

	Prints("%s\n", HostMessage{
		op:   "remove",
		Host: hostGlob,
	})
}

// isValidSecretKey - validate secret key
func isValidSecretKey(secretAccessKey string) bool {
	if secretAccessKey == "" {
		return true
	}
	regex := regexp.MustCompile("^.{40}$")
	return regex.MatchString(secretAccessKey)
}

// isValidAccessKey - validate access key
func isValidAccessKey(accessKeyID string) bool {
	if accessKeyID == "" {
		return true
	}
	regex := regexp.MustCompile("^[A-Z0-9\\-\\.\\_\\~]{20}$")
	return regex.MatchString(accessKeyID)
}

// addHost - add new host
func addHost(hostGlob, accessKeyID, secretAccessKey, api string) {
	if strings.TrimSpace(hostGlob) == "" {
		fatalIf(errDummy().Trace(), "Unable to proceed, empty arguments provided.")
	}
	if strings.TrimSpace(api) == "" {
		api = "S3v4"
	}
	if strings.TrimSpace(api) != "S3v2" && strings.TrimSpace(api) != "S3v4" {
		fatalIf(errInvalidArgument().Trace(), "Unrecognized version name provided, supported inputs are ‘S3v4’, ‘S3v2’")
	}
	config, err := newConfig()
	fatalIf(err.Trace(globalMCConfigVersion), "Failed to initialize ‘quick’ configuration data structure.")

	configPath := mustGetMcConfigPath()
	err = config.Load(configPath)
	fatalIf(err.Trace(configPath), "Unable to load config path")

	if len(accessKeyID) != 0 {
		if !isValidAccessKey(accessKeyID) {
			fatalIf(errInvalidArgument().Trace(), "Invalid access key id provided.")
		}
	}
	if len(secretAccessKey) != 0 {
		if !isValidSecretKey(secretAccessKey) {
			fatalIf(errInvalidArgument().Trace(), "Invalid secret access key provided.")
		}
	}
	// convert interface{} back to its original struct
	newConf := config.Data().(*configV5)
	newConf.Hosts[hostGlob] = hostConfig{
		AccessKeyID:     accessKeyID,
		SecretAccessKey: secretAccessKey,
		API:             api,
	}
	newConfig, err := quick.New(newConf)
	fatalIf(err.Trace(globalMCConfigVersion), "Failed to initialize ‘quick’ configuration data structure.")

	err = writeConfig(newConfig)
	fatalIf(err.Trace(hostGlob), "Unable to save host glob ‘"+hostGlob+"’.")

	Prints("%s\n", HostMessage{
		op:              "add",
		Host:            hostGlob,
		AccessKeyID:     accessKeyID,
		SecretAccessKey: secretAccessKey,
		API:             api,
	})
}