import { MaybePromise, Nullable } from 'tsdef';

import { FileActionState } from './action-handler.types';
import { FileViewConfig } from './file-view.types';
import { FileFilter, FileMap } from './file.types';
import { ChonkyIconName } from './icons.types';
import { ChonkyDispatch, RootState } from './redux.types';
import { FileSortKeySelector } from './sort.types';

export interface FileAction {
    /**
     * Unique file action ID. If you set the action ID to one of the built-in Chonky
     * action action IDs, you custom action definition will override the built-in
     * definition.
     */
    id: string;
    /**
     * When set to `true`, the action will only be active (dispatchable) when user
     * selects one or more files. If `fileFilter` is defined, it will be applied to
     * selection before checking if its empty.
     */
    requiresSelection?: boolean; // Requires selection of 1+ files
    /**
     * A predicate that determines whether a file should be included in the selection
     * for this action.
     */
    fileFilter?: FileFilter;
    /**
     * List of hotkeys that should trigger this action, defined using `hotkey-js`
     * notation.
     * @see https://www.npmjs.com/package/hotkeys-js
     */
    hotkeys?: string[] | readonly string[];
    /**
     * When button is defined and `toolbar` or `contextMenu` is set to `true`, a
     * button will be added to the relevant UI component. Clicking on this button
     * will active this action. The appearance of the button will change based on
     * the action definition and the current Chonky state.
     */
    button?: FileActionButton;
    /**
     * When `sortKeySelector` is specified, the action becomes a sorting toggle. When
     * this action is activated, it will sort files using the key selector, toggling
     * between Ascending and Descending orders.
     */
    sortKeySelector?: FileSortKeySelector;
    /**
     * When `fileViewConfig` is specified, triggering this action will apply the
     * provided config to Chonky's file view.
     */
    fileViewConfig?: FileViewConfig;
    /**
     * When `option` is specified, the action becomes an option toggle. When the action
     * is activated, the boolean value of the option will be toggled.
     */
    option?: FileActionOption;
    /**
     * When selection transform is defined, activating this action will update the file
     * selection. If the transform function returns `null`, selection will be left
     * untouched.
     */
    selectionTransform?: FileSelectionTransform;
    /**
     * When effect is defined, it will be called right before dispatching the action to
     * the user defined action handler. If the effect function returns a promise, Chonky
     * will wait for the promise to resolve or fail before dispatching the action to the
     * handler. If this function returns `true`, the file action will NOT be dispatched
     * the the handler.
     */
    effect?: FileActionEffect;
    /**
     * When customVisibility is defined, it will change the display state of the file action
     * The function must return the visibility as one of the CustomVisibilityState values:
     *  - Hidden
     *  - Disabled
     *  - Default
     *  - Active
     */
    customVisibility?: () => CustomVisibilityState;
    /**
     * Field used to infer the type of action payload. It is used solely for Typescript
     * type inference and action validation.
     */
    __payloadType?: any;
    /**
     * Field used to infer the type of extra state for this action. It is used solely
     * for Typescript type inference and action validation.
     */
    __extraStateType?: any;
}

export interface FileActionButton {
    name: string; // Button name
    toolbar?: boolean; // Whether to show the button in the toolbar
    contextMenu?: boolean; // Whether to show the button in the context menu
    group?: string; // Button group (dropdown in toolbar or section in context menu)
    tooltip?: string; // Help tooltip text
    icon?: ChonkyIconName | string | any; // Icon name
    iconOnly?: boolean; // Whether to only display the icon
}

export interface FileActionOption {
    id: string; // Unique option ID
    defaultValue: boolean; // Whether the option is enabled by default (required)
}

export type FileSelectionTransform = (data: {
    prevSelection: Set<string>;
    fileIds: ReadonlyArray<string>;
    fileMap: Readonly<FileMap>;
    hiddenFileIds: Set<string>;
}) => Nullable<Set<string>>;

export type FileActionEffect<Action extends FileAction = any> = (data: {
    action: Action;
    payload: Action['__payloadType'];
    state: FileActionState<{}>; // extra state is empty on purpose
    reduxDispatch: ChonkyDispatch;
    getReduxState: () => RootState;
}) => MaybePromise<undefined | boolean | void>;

export type FileActionMap = { [actonId: string]: FileAction };

export enum CustomVisibilityState {
    Hidden, 
    Disabled, 
    Default,
    Active
};