package commandkit

import (
	"fmt"

	commandmeta "gitea.maximumdirect.net/eric/CommandKit/internal/commandmeta"
)

// App owns one command registry and its application identity. Each App has an
// independent registry; command declarations may be reused across Apps.
type App struct {
	identity Identity
	commands map[string]*commandNode
	snapshot *routingSnapshot
}

type routingSnapshot struct {
	metadata *commandmeta.Command
	runners  map[commandmeta.Key]commandPayload
}

type commandNode struct {
	command Command
}

// New creates an application with the supplied identity and initial commands.
// The identity name must not be empty. New installs its generated help and
// version commands and caller declarations as one batch; an invalid declaration
// returns an error without exposing an App. The root help and version names are
// reserved for generated commands.
func New(identity Identity, commands ...Command) (*App, error) {
	if identity.Name == "" {
		return nil, fmt.Errorf("application identity name must not be empty")
	}

	app := &App{identity: identity, commands: make(map[string]*commandNode)}
	all := append(app.builtinCommands(), commands...)
	if err := app.installBatch(all...); err != nil {
		return nil, err
	}
	return app, nil
}