package repl

import (
	"errors"
	"fmt"
	"strings"

	"git.lyda.ie/kevin/bulletin/ask"
	"git.lyda.ie/kevin/bulletin/dclish"
	"git.lyda.ie/kevin/bulletin/key"
	"git.lyda.ie/kevin/bulletin/storage"
	"git.lyda.ie/kevin/bulletin/this"
	"git.lyda.ie/kevin/bulletin/users"
)

// ActionUser handles the USER command - it prints out help for all the
// USER subcommands.  This is new to the Go version of BULLETIN.
func ActionUser(cmd *dclish.Command) error {
	fmt.Println(cmd.Description)
	return nil
}

// ActionUserAdd handles the `USER ADD` command.  This is used to add a
// new user.  This is new to the Go version of BULLETIN.
func ActionUserAdd(cmd *dclish.Command) error {
	ctx := storage.Context()
	login := strings.ToUpper(cmd.Args[0])
	u, err := users.ValidExistingLogin(this.Q, login)
	if err != nil {
		fmt.Printf("ERROR: %s.\n", err)
		return nil
	}
	if u.Login != "" {
		fmt.Println("ERROR: User already exists.")
		return nil
	}
	u, err = this.Q.AddUser(ctx, storage.AddUserParams{
		Login: login,
		Name:  cmd.Args[1],
	})
	if err != nil {
		fmt.Printf("ERROR: %s.\n", err)
		return nil
	}
	if u.Login == "" {
		fmt.Println("ERROR: Failed to make user; unknown reason.")
		return nil
	}
	return nil
}

// ActionUserList handles the `USER LIST` command.  This lists all the
// users.  For now this is limited to only the admin users.
//
// This is new to the Go version of BULLETIN.
func ActionUserList(_ *dclish.Command) error {
	if this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	ctx := storage.Context()
	userlist, err := this.Q.ListUsers(ctx)
	if err != nil {
		fmt.Printf("ERROR: Failed to list users (%s).\n", err)
		return nil
	}
	for _, u := range userlist {
		fmt.Printf("%s\n", u)
	}
	return nil
}

// ActionUserDelete handles the `USER DELETE` command.  This will delete
// the named user.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserDelete(cmd *dclish.Command) error {
	if this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	u, err := users.ValidExistingLogin(this.Q, cmd.Args[0])
	if err != nil || u.Login == "" {
		fmt.Println("ERROR: User not found.")
		return nil
	}
	ctx := storage.Context()
	err = this.Q.DeleteUser(ctx, u.Login)
	if err != nil {
		fmt.Printf("ERROR: Failed to delete user (%s).\n", err)
		return nil
	}
	fmt.Println("User deleted.")
	return nil
}

func actionUserEnable(cmd *dclish.Command, disabled int64, doing string) error {
	if this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	u, err := users.ValidExistingLogin(this.Q, cmd.Args[0])
	if err != nil || u.Login == "" {
		fmt.Println("ERROR: User not found.")
		return nil
	}
	if u.Disabled == disabled {
		fmt.Printf("User already %sd.\n", doing)
		return nil
	}
	ctx := storage.Context()
	err = this.Q.UpdateUserDisabled(ctx, disabled, u.Login)
	if err != nil {
		fmt.Printf("ERROR: Failed to %s user (%s).\n", doing, err)
		return nil
	}
	fmt.Printf("User %sd.\n", doing)
	return nil
}

// ActionUserEnable handles the `USER ENABLE` command.  This enables
// a user.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserEnable(cmd *dclish.Command) error {
	return actionUserEnable(cmd, 0, "enable")
}

// ActionUserDisable handles the `USER DISABLE` command.  This disables
// a user.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserDisable(cmd *dclish.Command) error {
	return actionUserEnable(cmd, 1, "disable")
}

func actionUserAdmin(cmd *dclish.Command, admin int64, doing string) error {
	if this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	u, err := users.ValidExistingLogin(this.Q, cmd.Args[0])
	if err != nil || u.Login == "" {
		return errors.New("User not found")
	}
	if u.Login == this.User.Login || u.Login == "SYSTEM" {
		return errors.New("Invalid user given")
	}
	if u.Admin == admin {
		fmt.Printf("User is already %s.\n", doing)
		return nil
	}
	ctx := storage.Context()
	err = this.Q.UpdateUserAdmin(ctx, admin, u.Login)
	if err != nil {
		return fmt.Errorf("Failed to make user %s (%s)", doing, err)
	}
	fmt.Printf("User is now %s.\n", doing)
	return nil
}

// ActionUserAdmin handles the `USER ADMIN` command.  This makes the given
// user an admin.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserAdmin(cmd *dclish.Command) error {
	return actionUserAdmin(cmd, 1, "an admin")
}

// ActionUserNoadmin handles the `USER NOADMIN` command.  This removes the
// admin bit from a given user.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserNoadmin(cmd *dclish.Command) error {
	return actionUserAdmin(cmd, 0, "not an admin")
}

func actionUserMod(cmd *dclish.Command, mod int64, doing string) error {
	if this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	u, err := users.ValidExistingLogin(this.Q, cmd.Args[0])
	if err != nil || u.Login == "" {
		fmt.Println("ERROR: User not found.")
		return nil
	}
	if u.Moderator == mod {
		fmt.Printf("User is already %s.\n", doing)
		return nil
	}
	ctx := storage.Context()
	err = this.Q.UpdateUserMod(ctx, mod, u.Login)
	if err != nil {
		fmt.Printf("ERROR: Failed to make user %s (%s).\n", doing, err)
		return nil
	}
	fmt.Printf("User is now %s.\n", doing)
	return nil
}

// ActionUserMod handles the `USER MOD` command.  Makes given the user a
// moderator.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserMod(cmd *dclish.Command) error {
	return actionUserMod(cmd, 1, "a moderator")
}

// ActionUserNomod handles the `USER NOMOD` command.  Removes the
// moderator bit from the given user.  Only the admin can use this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserNomod(cmd *dclish.Command) error {
	return actionUserMod(cmd, 0, "not a moderator")
}

// ActionUserName handles the `USER NAME` command. Updates the user's
// name.  Only the admin can use the two argument version of this command.
//
// This is new to the Go version of BULLETIN.
func ActionUserName(cmd *dclish.Command) error {
	if len(cmd.Args) == 2 && this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	login := this.User.Login
	name := cmd.Args[0]
	if len(cmd.Args) == 2 {
		login = strings.ToUpper(cmd.Args[0])
		name = cmd.Args[1]
		_, err := users.ValidExistingLogin(this.Q, login)
		if err != nil {
			fmt.Printf("ERROR: %s.\n", err)
			return nil
		}
	}
	ctx := storage.Context()
	err := this.Q.UpdateUserName(ctx, name, login)
	if err != nil {
		fmt.Printf("ERROR: Failed to update user name (%s).\n", err)
	}
	return nil
}

// ActionSSH handles the `SSH` command.  This prints the help for all the
// SSH commands.  These are used to manage the authorized_keys file.
// These are new to the Go version of BULLETIN.
func ActionSSH(cmd *dclish.Command) error {
	fmt.Println(cmd.Description)
	return nil
}

// ActionSSHAdd handles the `SSH ADD` command.  This adds a given ssh key
// to the authorized_keys file for the given user.  An admin can add
// a new public key for another user.
//
// This is new to the Go version of BULLETIN.
func ActionSSHAdd(cmd *dclish.Command) error {
	if this.User.Admin == 0 && len(cmd.Args) == 1 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	login := this.User.Login
	if len(cmd.Args) == 1 {
		login = cmd.Args[0]
	}
	u, err := users.ValidExistingLogin(this.Q, login)
	if err != nil || u.Login == "" {
		fmt.Println("ERROR: User not found.")
		return nil
	}
	sshkey, err := ask.GetLine("Enter ssh public key: ")
	if err != nil {
		fmt.Printf("ERROR: Failed to read ssh key (%s).\n", err)
		return nil
	}
	key.Add(u.Login, sshkey)
	fmt.Println("Key is added.")
	return nil
}

// ActionSSHList handles the `SSH LIST` command.  This lists all the
// public keys for this user.  An admin can list public keys for another
// user.
//
// This is new to the Go version of BULLETIN.
func ActionSSHList(cmd *dclish.Command) error {
	if this.User.Admin == 0 && len(cmd.Args) == 1 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	login := this.User.Login
	if len(cmd.Args) == 1 {
		login = cmd.Args[0]
	}
	u, err := users.ValidExistingLogin(this.Q, login)
	if err != nil || u.Login == "" {
		fmt.Println("ERROR: User not found.")
		return nil
	}
	keys, err := key.List(login)
	if err != nil {
		fmt.Printf("ERROR: Problem listing keys (%s).\n", err)
		return nil
	}
	fmt.Printf("The %d keys:\n  %s\n", len(keys), strings.Join(keys, "\n  "))
	return nil
}

// ActionSSHDelete handles the `SSH DELETE` command.  Removes ssh public
// keys for a user.  And admin can specify a different user to remove
// public keys for.
//
// This is new to the Go version of BULLETIN.
func ActionSSHDelete(cmd *dclish.Command) error {
	if this.User.Admin == 0 && len(cmd.Args) == 1 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	login := this.User.Login
	if len(cmd.Args) == 1 {
		login = cmd.Args[0]
	}
	u, err := users.ValidExistingLogin(this.Q, login)
	if err != nil || u.Login == "" {
		fmt.Println("ERROR: User not found.")
		return nil
	}
	keys, err := key.List(login)
	if err != nil {
		fmt.Printf("ERROR: Problem listing keys (%s).\n", err)
		return nil
	}
	if len(keys) == 0 {
		fmt.Println("No keys to delete.")
		return nil
	}
	choice, err := ask.Choose("Choose a key to delete:", keys)
	if err != nil {
		fmt.Printf("ERROR: Problem choosing key (%s).\n", err)
		return nil
	}
	if choice < 0 {
		fmt.Println("Aborted.")
		return nil
	}
	err = key.Delete(keys[choice])
	if err != nil {
		fmt.Printf("ERROR: Problem deleting key (%s).\n", err)
		return nil
	}
	fmt.Println("Key deleted.")
	return nil
}

// ActionSSHFetch handles the `SSH FETCH` command.  This command pulls
// public keys from code sites.  It's the quickest way to
// add a number of keys for a user.  An admin can do this
// for another user.
//
// This is new to the Go version of BULLETIN.
func ActionSSHFetch(cmd *dclish.Command) error {
	login := this.User.Login
	sitename := cmd.Args[0]
	username := cmd.Args[1]
	if len(cmd.Args) == 3 && this.User.Admin == 0 {
		fmt.Println("ERROR: You are not an admin.")
		return nil
	}
	if len(cmd.Args) == 3 {
		login = cmd.Args[0]
		sitename = cmd.Args[1]
		username = cmd.Args[2]
	}
	fmt.Print(key.Fetch(login, sitename, username))
	return nil
}