// Copyright © 2019 Ettore Di Giacinto <mudler@gentoo.org>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"fmt"
	"os"

	"github.com/marcsauter/single"
	"github.com/mudler/luet/cmd/util"
	bus "github.com/mudler/luet/pkg/bus"

	config "github.com/mudler/luet/pkg/config"
	. "github.com/mudler/luet/pkg/logger"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"
)

var cfgFile string
var Verbose bool
var LockedCommands = []string{"install", "uninstall", "upgrade"}

const (
	LuetCLIVersion = "0.18.1"
	LuetEnvPrefix  = "LUET"
	license        = `
	Luet Copyright (C) 2019-2021 Ettore Di Giacinto
	This program comes with ABSOLUTELY NO WARRANTY.
	This is free software, and you are welcome to redistribute it
	under certain conditions.
	`
)

// Build time and commit information.
//
// ⚠️ WARNING: should only be set by "-ldflags".
var (
	BuildTime   string
	BuildCommit string
)

func version() string {
	return fmt.Sprintf("%s-g%s %s", LuetCLIVersion, BuildCommit, BuildTime)
}

var bannerCommands = []string{"install", "build", "uninstall", "upgrade"}

func displayVersionBanner() {
	display := false
	if len(os.Args) > 1 {
		for _, c := range bannerCommands {
			if os.Args[1] == c {
				display = true
			}
		}
	}
	if display {
		util.IntroScreen()
		Info("Luet version", version())
		Info(license)
	}
}

func handleLock() {
	if os.Getenv("LUET_NOLOCK") != "true" {
		if len(os.Args) > 1 {
			for _, lockedCmd := range LockedCommands {
				if os.Args[1] == lockedCmd {
					s := single.New("luet")
					if err := s.CheckLock(); err != nil && err == single.ErrAlreadyRunning {
						Fatal("another instance of the app is already running, exiting")
					} else if err != nil {
						// Another error occurred, might be worth handling it as well
						Fatal("failed to acquire exclusive app lock:", err.Error())
					}
					defer s.TryUnlock()
					break
				}
			}
		}
	}
}

// RootCmd represents the base command when called without any subcommands
var RootCmd = &cobra.Command{
	Use:   "luet",
	Short: "Container based package manager",
	Long: `Luet is a single-binary package manager based on containers to build packages.
	
To install a package:

	$ luet install package

To search for a package in the repositories:

$ luet search package

To list all packages installed in the system:

	$ luet search --installed .

To show hidden packages:

	$ luet search --hidden package

To build a package, from a tree definition:

	$ luet build --tree tree/path package
	
`,
	Version: version(),
	PersistentPreRun: func(cmd *cobra.Command, args []string) {

		_, err := util.LoadConfig()
		if err != nil {
			Fatal("failed to load configuration:", err.Error())
		}

		// Initialize tmpdir prefix. TODO: Move this with LoadConfig
		// directly on sub command to ensure the creation only when it's
		// needed.
		err = config.LuetCfg.GetSystem().InitTmpDir()
		if err != nil {
			Fatal("failed on init tmp basedir:", err.Error())
		}

		viper.BindPFlag("plugin", cmd.Flags().Lookup("plugin"))

		plugin := viper.GetStringSlice("plugin")

		bus.Manager.Initialize(plugin...)
		if len(bus.Manager.Plugins) != 0 {
			Info(":lollipop:Enabled plugins:")
			for _, p := range bus.Manager.Plugins {
				Info("\t:arrow_right:", p.Name)
			}
		}
	},
	PersistentPostRun: func(cmd *cobra.Command, args []string) {
		// Cleanup all tmp directories used by luet
		err := config.LuetCfg.GetSystem().CleanupTmpDir()
		if err != nil {
			Warning("failed on cleanup tmpdir:", err.Error())
		}
	},
	SilenceErrors: true,
}

// Execute adds all child commands to the root command sets flags appropriately.
// This is called by main.main(). It only needs to happen once to the rootCmd.
func Execute() {

	handleLock()
	displayVersionBanner()

	if err := RootCmd.Execute(); err != nil {
		fmt.Println(err)
		os.Exit(-1)
	}
}

func init() {
	util.InitViper(RootCmd)
}