package cmd

import (
	"context"
	"os"
	"os/signal"
	"path/filepath"
	"regexp"
	"strings"

	"github.com/pterm/pterm"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"

	"gitea.libretechconsulting.com/rmcguire/git-project-manager/cmd/alias"
	"gitea.libretechconsulting.com/rmcguire/git-project-manager/cmd/cache"
	conf "gitea.libretechconsulting.com/rmcguire/git-project-manager/cmd/config"
	"gitea.libretechconsulting.com/rmcguire/git-project-manager/cmd/project"
	"gitea.libretechconsulting.com/rmcguire/git-project-manager/cmd/util"
	"gitea.libretechconsulting.com/rmcguire/git-project-manager/internal/config"
)

var rootCmd = &cobra.Command{
	Use:              "git-project-manager",
	Aliases:          []string{"gpm"},
	Short:            "Find and use Git projects locally",
	Long:             util.RootCmdLong,
	PersistentPreRun: initRootCmd,
}

var (
	Version              = "development"
	configExemptCommands = regexp.MustCompile(`^(doc|conf)`)
	utils                *util.Utils
)

// Hook traversal is enabled, so this will be run for all
// sub-commands regardless of their registered pre-hooks
func initRootCmd(cmd *cobra.Command, args []string) {
	cmd.SetContext(util.AddToCtx(cmd.Context(), utils))
	utils.InitProjectPath(cmd, args)
}

// Execute adds all child commands to the root command and sets flags appropriately.
// This is called by main.main(). It only needs to happen once to the rootCmd.
func Execute() {
	ctx, cncl := signal.NotifyContext(context.Background(), os.Kill, os.Interrupt)
	defer cncl()

	err := rootCmd.ExecuteContext(ctx)
	if err != nil {
		pterm.Error.Printfln("%s", pterm.LightYellow("Command failed, "+err.Error()))
		os.Exit(1)
	}
}

func init() {
	cobra.EnableTraverseRunHooks = true

	utils = &util.Utils{}
	cobra.OnInitialize(getInitConfigFunc(utils))

	// Global flags
	rootCmd.PersistentFlags().String(util.FlagConfig, "",
		"config file (default is "+util.DefConfigPath+")")
	rootCmd.PersistentFlags().String(util.FlagPath, "",
		"Sets a path for local clones of projects")
	rootCmd.PersistentFlags().String(util.FlagLogLevel, util.DefLogLevel,
		"Default log level -- info, warn, error, debug")
	rootCmd.PersistentFlags().StringSlice(util.FlagRemote, []string{},
		"Specify remotes by host for any sub-command. Provide multiple times or comma delimited.")

	viper.BindPFlags(rootCmd.PersistentFlags())

	// Flag autocompletion
	rootCmd.RegisterFlagCompletionFunc(util.FlagLogLevel, util.ValidLogLevelsFunc)
	rootCmd.RegisterFlagCompletionFunc(util.FlagRemote, util.ValidRemotesFunc)

	// Subcommands
	rootCmd.AddCommand(alias.AliasCmd)
	rootCmd.AddCommand(cache.CacheCmd)
	rootCmd.AddCommand(conf.ConfigCmd)
	rootCmd.AddCommand(project.ProjectCmd)

	// Version
	rootCmd.Version = Version
}

// initConfig reads in config file and ENV variables if set.
func getInitConfigFunc(utils *util.Utils) func() {
	return func() {
		cfgFile := viper.GetString(util.FlagConfig)
		if cfgFile != "" {
			// Use config file from the flag.
			viper.SetConfigFile(cfgFile)
		} else {
			// Find home directory.
			home, err := os.UserHomeDir()
			cobra.CheckErr(err)

			// Search config in home directory with name ".git-project-manager" (without extension).
			configPath := filepath.Join(home, ".config")
			viper.AddConfigPath(configPath)
			viper.SetConfigType("yaml")
			viper.SetConfigName(util.GetConfigName(configPath))
		}

		viper.AutomaticEnv()
		viper.ReadInConfig()

		// Configure pretty logger
		plog := pterm.DefaultLogger.
			WithLevel(getPtermLogLevel(viper.GetString(util.FlagLogLevel))).
			WithWriter(os.Stderr)
		if plog.Level == pterm.LogLevelDebug {
			pterm.EnableDebugMessages()
		}
		utils.SetLogger(plog)

		// Load into struct to not be so darn pythonic, retrieving
		// settings by untyped string "name"
		conf := new(config.Config)
		if err := viper.Unmarshal(&conf); err != nil {
			plog.Error("Failed loading config", plog.Args("err", err))
		}

		utils.SetConfig(conf)

		if len(os.Args) > 0 && configExemptCommands.Match([]byte(os.Args[1])) {
			plog.Debug("Permitting missing config for config sub-command")
			return
		} else if conf.ProjectPath == "" {
			plog.Fatal("Minimal configuration missing, must have projectPath", plog.Args(
				"do",
				"Try running `git-project-manager config default > "+util.DefConfigPath,
			))
		}

		checkConfigPerms(viper.ConfigFileUsed()) // Abort on world-readable config

		utils.Logger().Debug("Configuration loaded", plog.Args("conf", conf))
	}
}

func getPtermLogLevel(level string) pterm.LogLevel {
	var pLevel pterm.LogLevel
	switch strings.ToLower(level) {
	case "error":
		pLevel = pterm.LogLevelError
	case "warn":
		pLevel = pterm.LogLevelWarn
	case "info":
		pLevel = pterm.LogLevelInfo
	case "debug":
		pLevel = pterm.LogLevelDebug
	default:
		pLevel = pterm.LogLevelInfo
	}
	return pLevel
}

// Don't allow world-readable configuration
func checkConfigPerms(file string) {
	stat, err := os.Stat(file)
	if err != nil {
		utils.Logger().Error("Failure reading configuration", utils.Logger().Args("err", err))
		return
	}
	if stat.Mode().Perm()&0o004 == 0o004 {
		utils.Logger().Error("Configuration is world-readable. Recomment 0400.",
			utils.Logger().Args("mode", stat.Mode().String()))
		os.Exit(1)
	}
}