package main

import (
	"encoding/base64"
	"encoding/json"
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"os"
	"strings"

	"github.com/cloudflare/redoctober/client"
	"github.com/cloudflare/redoctober/cmd/ro/gopass"
	"github.com/cloudflare/redoctober/core"
)

var action, user, pswd, userEnv, pswdEnv, server, caPath string

var owners, lefters, righters, inPath, labels, outPath, outEnv string

var uses int

var time, users string

type command struct {
	Run  func()
	Desc string
}

var roServer *client.RemoteServer

var commandSet = map[string]command{
	"create":     command{Run: runCreate, Desc: "create a user account"},
	"summary":    command{Run: runSummary, Desc: "list the user and delegation summary"},
	"delegate":   command{Run: runDelegate, Desc: "do decryption delegation"},
	"encrypt":    command{Run: runEncrypt, Desc: "encrypt a file"},
	"decrypt":    command{Run: runDecrypt, Desc: "decrypt a file"},
	"re-encrypt": command{Run: runReEncrypt, Desc: "re-encrypt a file"},
}

func registerFlags() {
	flag.StringVar(&server, "server", "localhost:8080", "server address")
	flag.StringVar(&caPath, "ca", "", "ca file path")
	flag.StringVar(&owners, "owners", "", "comma separated owner list")
	flag.StringVar(&users, "users", "", "comma separated user list")
	flag.IntVar(&uses, "uses", 0, "number of delegated key uses")
	flag.StringVar(&time, "time", "0h", "duration of delegated key uses")
	flag.StringVar(&lefters, "left", "", "comma separated left owners")
	flag.StringVar(&righters, "right", "", "comma separated right owners")
	flag.StringVar(&labels, "labels", "", "comma separated labels")
	flag.StringVar(&inPath, "in", "", "input data file")
	flag.StringVar(&outPath, "out", "", "output data file")
	flag.StringVar(&outEnv, "outenv", "", "env variable for output data")
	flag.StringVar(&user, "user", "", "username")
	flag.StringVar(&pswd, "password", "", "password")
	flag.StringVar(&userEnv, "userenv", "RO_USER", "env variable for user name")
	flag.StringVar(&pswdEnv, "pswdenv", "RO_PASS", "env variable for user password")
}

func getUserCredentials() {
	user = os.Getenv(userEnv)
	pswd = os.Getenv(pswdEnv)
	if user == "" || pswd == "" {
		fmt.Print("Username:")
		fmt.Scan(&user)
		var err error
		pswd, err = gopass.GetPass("Password:")
		processError(err)
	}
}

func processError(err error) {
	if err != nil {
		log.Fatal("error:", err)
	}
}

func processCSL(s string) []string {
	if s == "" {
		return nil
	}

	return strings.Split(s, ",")
}

func runCreate() {
	req := core.CreateRequest{
		Name:     user,
		Password: pswd,
	}
	resp, err := roServer.Create(req)
	processError(err)
	fmt.Println(resp.Status)
}

func runDelegate() {
	req := core.DelegateRequest{
		Name:     user,
		Password: pswd,
		Uses:     uses,
		Time:     time,
		Users:    processCSL(users),
		Labels:   processCSL(labels),
	}
	resp, err := roServer.Delegate(req)
	processError(err)
	fmt.Println(resp.Status)
}

// TODO: summary response needs better formatting
func runSummary() {
	req := core.SummaryRequest{
		Name:     user,
		Password: pswd,
	}
	resp, err := roServer.Summary(req)
	processError(err)
	fmt.Println(resp)
}

func runEncrypt() {
	inBytes, err := ioutil.ReadFile(inPath)
	processError(err)
	req := core.EncryptRequest{
		Name:        user,
		Password:    pswd,
		Owners:      processCSL(owners),
		LeftOwners:  processCSL(lefters),
		RightOwners: processCSL(righters),
		Labels:      processCSL(labels),
		Data:        inBytes,
	}

	resp, err := roServer.Encrypt(req)
	processError(err)
	if resp.Status != "ok" {
		log.Fatal("response status error:", resp.Status)
		return
	}
	fmt.Println("Response Status:", resp.Status)
	outBytes := []byte(base64.StdEncoding.EncodeToString(resp.Response))
	ioutil.WriteFile(outPath, outBytes, 0644)
}

func runReEncrypt() {
	inBytes, err := ioutil.ReadFile(inPath)
	processError(err)

	// base64 decode the input
	encBytes, err := base64.StdEncoding.DecodeString(string(inBytes))
	if err != nil {
		log.Println("fail to base64 decode the data, proceed with raw data")
		encBytes = inBytes
	}

	req := core.ReEncryptRequest{
		Name:        user,
		Password:    pswd,
		Owners:      processCSL(owners),
		LeftOwners:  processCSL(lefters),
		RightOwners: processCSL(righters),
		Labels:      processCSL(labels),
		Data:        encBytes,
	}

	resp, err := roServer.ReEncrypt(req)
	processError(err)
	if resp.Status != "ok" {
		log.Fatal("response status error:", resp.Status)
		return
	}
	fmt.Println("Response Status:", resp.Status)
	outBytes := []byte(base64.StdEncoding.EncodeToString(resp.Response))
	ioutil.WriteFile(outPath, outBytes, 0644)
}

func runDecrypt() {
	inBytes, err := ioutil.ReadFile(inPath)
	processError(err)

	// base64 decode the input
	encBytes, err := base64.StdEncoding.DecodeString(string(inBytes))
	if err != nil {
		log.Println("fail to base64 decode the data, proceed with raw data")
		encBytes = inBytes
	}

	req := core.DecryptRequest{
		Name:     user,
		Password: pswd,
		Data:     encBytes,
	}

	resp, err := roServer.Decrypt(req)
	processError(err)
	if resp.Status != "ok" {
		log.Fatal("response status error:", resp.Status)
		return
	}
	fmt.Println("Response Status:", resp.Status)
	var msg core.DecryptWithDelegates
	err = json.Unmarshal(resp.Response, &msg)
	processError(err)
	fmt.Println("Secure:", msg.Secure)
	fmt.Println("Delegates:", msg.Delegates)
	ioutil.WriteFile(outPath, msg.Data, 0644)
}

func main() {
	flag.Usage = func() {
		fmt.Println("Usage: ro [options] subcommand")
		fmt.Println("Currently supported subcommands are:")
		for key := range commandSet {
			fmt.Println("\t", key, ":", commandSet[key].Desc)
		}

		fmt.Println("Options:")
		flag.PrintDefaults()
	}

	registerFlags()
	flag.Parse()

	if flag.NArg() != 1 {
		flag.Usage()
		os.Exit(1)
	}

	action := flag.Arg(0)

	cmd, found := commandSet[action]
	if !found {
		fmt.Println("Unsupported subcommand:", action)
		flag.Usage()
		os.Exit(1)
	} else {
		var err error
		roServer, err = client.NewRemoteServer(server, caPath)
		processError(err)

		getUserCredentials()
		cmd.Run()
	}
}