/*
 * Copyright (C) 2017-2019 "IoT.bzh"
 * Author Sebastien Douheret <sebastien@iot.bzh>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *
 * xds-cli: command line tool used to control / interface X(cross) Development System.
 */

package main

import (
	"fmt"
	"os"
	"path"
	"regexp"
	"sort"
	"strings"
	"syscall"
	"text/tabwriter"

	"gerrit.automotivelinux.org/gerrit/src/xds/xds-agent.git/lib/xaapiv1"
	common "gerrit.automotivelinux.org/gerrit/src/xds/xds-common.git"
	"github.com/Sirupsen/logrus"
	"github.com/joho/godotenv"
	"github.com/urfave/cli"
)

var appAuthors = []cli.Author{
	cli.Author{Name: "Sebastien Douheret", Email: "sebastien@iot.bzh"},
}

// AppName name of this application
var AppName = "xds-cli"

// AppNativeName native command name that this application can overload
var AppNativeName = "cli"

// AppVersion Version of this application
// (set by Makefile)
var AppVersion = "?.?.?"

// AppSubVersion is the git tag id added to version string
// Should be set by compilation -ldflags "-X main.AppSubVersion=xxx"
// (set by Makefile)
var AppSubVersion = "unknown-dev"

// Application details
const (
	appCopyright             = "Copyright (C) 2017-2019 IoT.bzh - Apache-2.0"
	defaultLogLevel          = "error"
	defaultConfigEnvFilename = "cli-config.env"
)

// Log Global variable that hold logger
var Log = logrus.New()

// EnvConfFileMap Global variable that hold environment vars loaded from config file
var EnvConfFileMap map[string]string

// HTTPCli Global variable that hold HTTP Client
var HTTPCli *common.HTTPClient

// IOSkClient Global variable that hold SocketIo client
var IOSkClient *IOSockClient

// exitError exists this program with the specified error
func exitError(code int, f string, a ...interface{}) {
	earlyDisplay()
	err := fmt.Sprintf(f, a...)
	fmt.Fprintf(os.Stderr, err+"\n")
	os.Exit(code)
}

// earlyDebug Used to log info before logger has been initialized
var earlyDebug []string

func earlyPrintf(format string, args ...interface{}) {
	earlyDebug = append(earlyDebug, fmt.Sprintf(format, args...))
}

func earlyDisplay() {
	for _, str := range earlyDebug {
		Log.Infof("%s", str)
	}
	earlyDebug = []string{}
}

// LogSillyf Logging helper used for silly logging (printed on log.debug)
func LogSillyf(format string, args ...interface{}) {
	sillyVal, sillyLog := os.LookupEnv("XDS_LOG_SILLY")
	if sillyLog && sillyVal == "1" {
		Log.Debugf("SILLY: "+format, args...)
	}
}

// main
func main() {

	// Allow to set app name from cli (useful for debugging)
	if AppName == "" {
		AppName = os.Getenv("XDS_APPNAME")
	}
	if AppName == "" {
		panic("Invalid setup, AppName not define !")
	}
	if AppNativeName == "" {
		AppNativeName = AppName[4:]
	}
	appUsage := fmt.Sprintf("command line tool for X(cross) Development System.")
	appDescription := fmt.Sprintf("%s utility for X(cross) Development System\n", AppName)
	appDescription += `
    Setting of global options is driven either by environment variables or by command
    line options or using a config file knowning that the following priority order is used:
      1. use option value (for example --url option),
      2. else use variable 'XDS_xxx' (for example 'XDS_AGENT_URL' variable) when a
         config file is specified with '--config|-c' option,
      3. else use 'XDS_xxx' (for example 'XDS_AGENT_URL') environment variable.

    Examples:
    # Get help of 'projects' sub-command
    ` + AppName + ` projects --help

    # List all SDKs
    ` + AppName + ` sdks ls

    # Add a new project
    ` + AppName + ` prj add --label="myProject" --type=cs --path=$HOME/xds-workspace/myProject
`

	// Create a new App instance
	app := cli.NewApp()
	app.Name = AppName
	app.Usage = appUsage
	app.Version = AppVersion + " (" + AppSubVersion + ")"
	app.Authors = appAuthors
	app.Copyright = appCopyright
	app.Metadata = make(map[string]interface{})
	app.Metadata["version"] = AppVersion
	app.Metadata["git-tag"] = AppSubVersion
	app.Metadata["logger"] = Log
	// FIXME: Disable completion for now, because it's not working with options
	// (eg. --label) and prevents to complete local path
	// (IOW current function only completes command and sub-commands)
	app.EnableBashCompletion = false

	// Create env vars help
	dynDesc := "\nENVIRONMENT VARIABLES:"
	for _, f := range app.Flags {
		var env, usage string
		switch f.(type) {
		case cli.StringFlag:
			fs := f.(cli.StringFlag)
			env = fs.EnvVar
			usage = fs.Usage
		case cli.BoolFlag:
			fb := f.(cli.BoolFlag)
			env = fb.EnvVar
			usage = fb.Usage
		default:
			exitError(1, "Un-implemented option type")
		}
		if env != "" {
			dynDesc += fmt.Sprintf("\n %s \t\t %s", env, usage)
		}
	}
	app.Description = appDescription + dynDesc

	// Declare global flags
	app.Flags = []cli.Flag{
		cli.StringFlag{
			Name:   "config, c",
			EnvVar: "XDS_CONFIG",
			Usage:  "env config file to source on startup",
		},
		cli.StringFlag{
			Name:   "log, l",
			EnvVar: "XDS_LOGLEVEL",
			Usage:  "logging level (supported levels: panic, fatal, error, warn, info, debug)",
			Value:  defaultLogLevel,
		},
		cli.StringFlag{
			Name:   "logfile",
			Value:  "stderr",
			Usage:  "filename where logs will be redirected (default stderr)\n\t",
			EnvVar: "XDS_LOGFILENAME",
		},
		cli.StringFlag{
			Name:   "url, u",
			EnvVar: "XDS_AGENT_URL",
			Value:  "localhost:8800",
			Usage:  "local XDS agent url",
		},
		cli.StringFlag{
			Name:   "url-server, us",
			EnvVar: "XDS_SERVER_URL",
			Value:  "",
			Usage:  "overwrite remote XDS server url (default value set in xds-agent-config.json file)",
		},
		cli.BoolFlag{
			Name:   "timestamp, ts",
			EnvVar: "XDS_TIMESTAMP",
			Usage:  "prefix output with timestamp",
		},
	}

	// Declare commands
	app.Commands = []cli.Command{}

	initCmdProjects(&app.Commands)
	initCmdSdks(&app.Commands)
	initCmdExec(&app.Commands)
	initCmdTargets(&app.Commands)
	initCmdMisc(&app.Commands)

	// Add --config option to all commands to support --config option either before or after command verb
	// IOW support following both syntaxes:
	//   xds-cli exec --config myPrj.conf ...
	//   xds-cli --config myPrj.conf exec ...
	for i, cmd := range app.Commands {
		if len(cmd.Flags) > 0 {
			app.Commands[i].Flags = append(cmd.Flags, cli.StringFlag{Hidden: true, Name: "config, c"})
		}
		for j, subCmd := range cmd.Subcommands {
			app.Commands[i].Subcommands[j].Flags = append(subCmd.Flags, cli.StringFlag{Hidden: true, Name: "config, c"})
		}
	}

	sort.Sort(cli.FlagsByName(app.Flags))
	sort.Sort(cli.CommandsByName(app.Commands))

	// Early and manual processing of --config option in order to set XDS_xxx
	// variables before parsing of option by app cli
	//  1/ from command line option: "--config myConfig.json"
	//  2/ from environment variable XDS_CONFIG
	//  3/ $HOME/.xds/cli/cli-config.env file
	//  4/ /etc/xds/cli/cli-config.env file
	searchIn := make([]string, 0, 4)
	for idx, a := range os.Args[1:] {
		if a == "-c" || a == "--config" || a == "-config" {
			searchIn = append(searchIn, os.Args[idx+2])
			break
		}
	}
	searchIn = append(searchIn, os.Getenv("XDS_CONFIG"))
	if usrHome := common.GetUserHome(); usrHome != "" {
		searchIn = append(searchIn, path.Join(usrHome, ".xds", "cli", defaultConfigEnvFilename))
	}
	searchIn = append(searchIn, path.Join("/etc", "xds", "cli", defaultConfigEnvFilename))

	// Use the first existing env config file
	confFile := ""
	for _, p := range searchIn {
		if pr, err := common.ResolveEnvVar(p); err == nil {
			earlyPrintf("Check if confFile exists : %v", pr)
			if common.Exists(pr) {
				confFile = pr
				break
			}
		}
	}

	// Load config file if requested
	if confFile != "" {
		earlyPrintf("Used confFile: %v", confFile)
		// Load config file variables that will overwrite env variables
		err := godotenv.Overload(confFile)
		if err != nil {
			exitError(1, "Error loading env config file "+confFile)
		}

		// Keep confFile settings in a map
		EnvConfFileMap, err = godotenv.Read(confFile)
		if err != nil {
			exitError(1, "Error reading env config file "+confFile)
		}
		earlyPrintf("EnvConfFileMap: %v", EnvConfFileMap)
	}

	app.Before = func(ctx *cli.Context) error {
		var err error

		// Don't init anything when no argument or help option is set
		if ctx.NArg() == 0 {
			return nil
		}
		for _, a := range ctx.Args() {
			switch a {
			case "-h", "--h", "-help", "--help":
				return nil
			}
		}

		loglevel := ctx.String("log")
		// Set logger level and formatter
		if Log.Level, err = logrus.ParseLevel(loglevel); err != nil {
			msg := fmt.Sprintf("Invalid log level : \"%v\"\n", loglevel)
			return cli.NewExitError(msg, 1)
		}
		Log.Formatter = &logrus.TextFormatter{}

		if ctx.String("logfile") != "stderr" {
			logFile, _ := common.ResolveEnvVar(ctx.String("logfile"))
			fdL, err := os.OpenFile(logFile, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0666)
			if err != nil {
				msgErr := fmt.Sprintf("Cannot create log file %s", logFile)
				return cli.NewExitError(msgErr, 1)
			}
			Log.Infof("Logging to file: %s", logFile)
			Log.Out = fdL
		}

		Log.Infof("%s version: %s", AppName, app.Version)
		earlyDisplay()
		Log.Debugf("\nEnvironment: %v\n", os.Environ())

		if err = XdsConnInit(ctx); err != nil {
			// Directly call HandleExitCoder to avoid to print help (ShowAppHelp)
			// Note that this function wil never return and program will exit
			cli.HandleExitCoder(err)
		}

		return nil
	}

	// Close HTTP client and WS connection on exit
	defer func() {
		XdsConnClose()
	}()

	// Start signals monitoring routine
	MonitorSignals()

	// Default callback to handle interrupt signal
	// Maybe be overwritten by some subcommand (eg. targets commands)
	err := OnSignals(func(sig os.Signal) {
		Log.Debugf("Send signal %v (from main)", sig)
		if IsInterruptSignal(sig) {
			err := cli.NewExitError("Interrupted\n", int(syscall.EINTR))
			cli.HandleExitCoder(err)
		}
	})
	if err != nil {
		cli.NewExitError(err.Error(), 1)
		return
	}

	// Run the cli app
	app.Run(os.Args)
}

// XdsConnInit Initialized HTTP and WebSocket connection to XDS agent
func XdsConnInit(ctx *cli.Context) error {
	var err error

	// Define HTTP and WS url
	agentURL := ctx.String("url")
	serverURL := ctx.String("url-server")

	// Allow to only set port number
	if match, _ := regexp.MatchString("^([0-9]+)$", agentURL); match {
		agentURL = "http://localhost:" + ctx.String("url")
	}
	if match, _ := regexp.MatchString("^([0-9]+)$", serverURL); match {
		serverURL = "http://localhost:" + ctx.String("url-server")
	}
	// Add http prefix if missing
	if agentURL != "" && !strings.HasPrefix(agentURL, "http://") {
		agentURL = "http://" + agentURL
	}
	if serverURL != "" && !strings.HasPrefix(serverURL, "http://") {
		serverURL = "http://" + serverURL
	}

	lvl := common.HTTPLogLevelWarning
	if Log.Level == logrus.DebugLevel {
		lvl = common.HTTPLogLevelDebug
	}

	// Create HTTP client
	Log.Debugln("Connect HTTP client on ", agentURL)
	conf := common.HTTPClientConfig{
		URLPrefix:           "/api/v1",
		HeaderClientKeyName: "Xds-Agent-Sid",
		CsrfDisable:         true,
		LogOut:              Log.Out,
		LogPrefix:           "XDSAGENT: ",
		LogLevel:            lvl,
	}

	HTTPCli, err = common.HTTPNewClient(agentURL, conf)
	if err != nil {
		errmsg := err.Error()
		m, err := regexp.MatchString("Get http.?://", errmsg)
		if (m && err == nil) || strings.Contains(errmsg, "Failed to get device ID") {
			i := strings.LastIndex(errmsg, ":")
			newErr := "Cannot connection to " + agentURL
			if i > 0 {
				newErr += " (" + strings.TrimSpace(errmsg[i+1:]) + ")"
			} else {
				newErr += " (" + strings.TrimSpace(errmsg) + ")"
			}
			errmsg = newErr
		}
		return cli.NewExitError(errmsg, 1)
	}
	HTTPCli.SetLogLevel(ctx.String("loglevel"))
	Log.Infoln("HTTP session ID : ", HTTPCli.GetClientID())

	// Create io Websocket client
	Log.Debugln("Connecting IO.socket client on ", agentURL)

	IOSkClient, err = NewIoSocketClient(agentURL, HTTPCli.GetClientID())
	if err != nil {
		return cli.NewExitError(err.Error(), 1)
	}

	IOSkClient.On("error", func(err error) {
		fmt.Println("ERROR Websocket: ", err.Error())
	})

	ctx.App.Metadata["httpCli"] = HTTPCli
	ctx.App.Metadata["ioskCli"] = IOSkClient

	// Display version in logs (debug helpers)
	ver := xaapiv1.XDSVersion{}
	if err := XdsVersionGet(&ver); err != nil {
		return cli.NewExitError("ERROR while retrieving XDS version: "+err.Error(), 1)
	}
	Log.Infof("XDS Agent/Server version: %v", ver)

	// Get current config and update connection to server when needed
	xdsConf := xaapiv1.APIConfig{}
	if err := XdsConfigGet(&xdsConf); err != nil {
		return cli.NewExitError("ERROR while getting XDS config: "+err.Error(), 1)
	}
	if len(xdsConf.Servers) < 1 {
		return cli.NewExitError("No XDS Server connected", 1)
	}
	svrCfg := xdsConf.Servers[XdsServerIndexGet()]
	if (serverURL != "" && svrCfg.URL != serverURL) || !svrCfg.Connected {
		Log.Infof("Update XDS Server config: serverURL=%v, svrCfg=%v", serverURL, svrCfg)
		if serverURL != "" {
			svrCfg.URL = serverURL
		}
		svrCfg.ConnRetry = 10
		if err := XdsConfigSet(xdsConf); err != nil {
			return cli.NewExitError("ERROR while updating XDS server URL: "+err.Error(), 1)
		}
	}

	return nil
}

// XdsConnClose Terminate connection to XDS agent
func XdsConnClose() {
	Log.Debugf("Closing HTTP client session...")
	/* TODO
	if httpCli, ok := app.Metadata["httpCli"]; ok {
		c := httpCli.(*common.HTTPClient)
	}
	*/

	Log.Debugf("Closing WebSocket connection...")
	/*
		if ioskCli, ok := app.Metadata["ioskCli"]; ok {
			c := ioskCli.(*socketio_client.Client)
		}
	*/
}

// NewTableWriter Create a writer that inserts padding around tab-delimited
func NewTableWriter() *tabwriter.Writer {
	writer := new(tabwriter.Writer)
	writer.Init(os.Stdout, 0, 8, 0, '\t', 0)
	return writer
}