import { IViewer } from "../viewer/IViewer";
/**
 * Defines the command executer service interface.
 */
export interface ICommandService {
    /**
     * Executes the command denoted by the given command ID.
     *
     * @param id - ID of the command to execute.
     * @param args - Parameters passed to the command handler function.
     * @returns Returns the result of the command handler function. Returns `undefined` when the command
     *   doesn't exists.
     */
    executeCommand(id: string, ...args: any[]): any;
}
/**
 * Defines the command map.
 */
export type ICommandsMap = Map<string, ICommand>;
/**
 * Defines the command handler function.
 */
export interface ICommandHandler {
    /**
     * @param viewer - Viewer instance that executes the command.
     * @param args - Parameters passed to the command handler function.
     */
    (viewer: any, ...args: any[]): any;
}
/**
 * Defines the command to execute by the {@link Viewer}.
 */
export interface ICommand {
    /**
     * Command ID.
     */
    id: string;
    /**
     * Handler function.
     */
    handler: ICommandHandler;
    /**
     * The `this` context used when invoking the handler function.
     */
    thisArg?: any;
    /**
     * Command description.
     */
    description?: ICommandDescription;
}
/**
 * Defines the command description.
 */
export interface ICommandDescription {
    /**
     * Command description string.
     */
    readonly description: string;
}
/**
 * Defines the viewer commands registry interface.
 */
export interface ICommandsRegistry {
    /**
     * Binds a command ID to a handler function. Registering a command with an existing ID twice overrides
     * the existing handler.
     *
     * @param id - Unique ID for the command.
     * @param handler - Command handler function.
     * @param description - Command description.
     * @param thisArg - The `this` context used when invoking the handler function.
     */
    registerCommand(id: string, handler: ICommandHandler, description?: ICommandDescription, thisArg?: any): void;
    /**
     * Registers an alias for a command.
     *
     * @param id - Unique ID for the command.
     * @param alias - Command alias string.
     */
    registerCommandAlias(id: string, alias: string): void;
    /**
     * Returns a list of registered commands.
     */
    getCommands(): ICommandsMap;
    /**
     * Returns the specified command or `undefined` when the command doesn't exists.
     *
     * @param id - Command ID.
     */
    getCommand(id: string): ICommand | undefined;
    /**
     * Executes the command denoted by the given command. If the command is not found, tries to set active
     * dragger with the specified name.
     *
     * @param id - Command ID or dragger name.
     * @param viewer - Viewer instance that wants to execute the command.
     * @param args - Parameters passed to the command handler function.
     * @returns Returns the result of the command handler function or new active dragger instance. Returns
     *   `undefined` if neither the command nor the dragger exists.
     */
    executeCommand(id: string, viewer: IViewer, ...args: any[]): any;
}