// Type definitions for non-npm package File System Access API 2020.09
// Project: https://github.com/WICG/file-system-access
// Definitions by: Ingvar Stepanyan <https://github.com/RReverser>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
// Minimum TypeScript Version: 3.5

export {};

declare class BaseFileSystemHandle {
    protected constructor();

    readonly kind: FileSystemHandleKind;
    readonly name: string;

    isSameEntry(other: FileSystemHandle): Promise<boolean>;
    queryPermission(descriptor?: FileSystemHandlePermissionDescriptor): Promise<PermissionState>;
    requestPermission(descriptor?: FileSystemHandlePermissionDescriptor): Promise<PermissionState>;

    /**
     * @deprecated Old property just for Chromium <=85. Use `kind` property in the new API.
     */
    readonly isFile: this['kind'] extends 'file' ? true : false;

    /**
     * @deprecated Old property just for Chromium <=85. Use `kind` property in the new API.
     */
    readonly isDirectory: this['kind'] extends 'directory' ? true : false;
}

declare global {
interface FilePickerAcceptType {
    description?: string | undefined;
    accept: Record<string, string | string[]>;
}

interface FilePickerOptions {
    types?: FilePickerAcceptType[] | undefined;
    excludeAcceptAllOption?: boolean | undefined;
}

interface OpenFilePickerOptions extends FilePickerOptions {
    multiple?: boolean | undefined;
}

interface SaveFilePickerOptions extends FilePickerOptions {
    suggestedName?: string;
}

// tslint:disable-next-line:no-empty-interface
interface DirectoryPickerOptions {}

type FileSystemPermissionMode = 'read' | 'readwrite';

interface FileSystemPermissionDescriptor extends PermissionDescriptor {
    handle: FileSystemHandle;
    mode?: FileSystemPermissionMode | undefined;
}

interface FileSystemHandlePermissionDescriptor {
    mode?: FileSystemPermissionMode | undefined;
}

type FileSystemHandleKind = 'file' | 'directory';

interface FileSystemCreateWritableOptions {
    keepExistingData?: boolean | undefined;
}

interface FileSystemGetFileOptions {
    create?: boolean | undefined;
}

interface FileSystemGetDirectoryOptions {
    create?: boolean | undefined;
}

interface FileSystemRemoveOptions {
    recursive?: boolean | undefined;
}

type WriteParams =
    | { type: 'write'; position?: number | undefined; data: BufferSource | Blob | string }
    | { type: 'seek'; position: number }
    | { type: 'truncate'; size: number };

type FileSystemWriteChunkType = BufferSource | Blob | string | WriteParams;

// TODO: remove this once https://github.com/microsoft/TSJS-lib-generator/issues/881 is fixed.
// Native File System API especially needs this method.
interface WritableStream {
    close(): Promise<void>;
}

class FileSystemWritableFileStream extends WritableStream {
    write(data: FileSystemWriteChunkType): Promise<void>;
    seek(position: number): Promise<void>;
    truncate(size: number): Promise<void>;
}

const FileSystemHandle: typeof BaseFileSystemHandle;
type FileSystemHandle = FileSystemFileHandle | FileSystemDirectoryHandle;

class FileSystemFileHandle extends FileSystemHandle {
    readonly kind: 'file';

    getFile(): Promise<File>;
    createWritable(options?: FileSystemCreateWritableOptions): Promise<FileSystemWritableFileStream>;
}

class FileSystemDirectoryHandle extends BaseFileSystemHandle {
    readonly kind: 'directory';

    getFileHandle(name: string, options?: FileSystemGetFileOptions): Promise<FileSystemFileHandle>;
    getDirectoryHandle(name: string, options?: FileSystemGetDirectoryOptions): Promise<FileSystemDirectoryHandle>;
    removeEntry(name: string, options?: FileSystemRemoveOptions): Promise<void>;
    resolve(possibleDescendant: FileSystemHandle): Promise<string[] | null>;

    keys(): AsyncIterableIterator<string>;
    values(): AsyncIterableIterator<FileSystemHandle>;
    entries(): AsyncIterableIterator<[string, FileSystemHandle]>;
    [Symbol.asyncIterator]: FileSystemDirectoryHandle['entries'];

    /**
     * @deprecated Old method just for Chromium <=85. Use `navigator.storage.getDirectory()` in the new API.
     */
    static getSystemDirectory(options: GetSystemDirectoryOptions): Promise<FileSystemDirectoryHandle>;
}

interface DataTransferItem {
    getAsFileSystemHandle(): Promise<FileSystemHandle | null>;
}

interface StorageManager {
    getDirectory(): Promise<FileSystemDirectoryHandle>;
}

function showOpenFilePicker(
    options?: OpenFilePickerOptions & { multiple?: false | undefined },
): Promise<[FileSystemFileHandle]>;
function showOpenFilePicker(options?: OpenFilePickerOptions): Promise<FileSystemFileHandle[]>;
function showSaveFilePicker(options?: SaveFilePickerOptions): Promise<FileSystemFileHandle>;
function showDirectoryPicker(options?: DirectoryPickerOptions): Promise<FileSystemDirectoryHandle>;

// Old methods available on Chromium 85 instead of the ones above.

interface ChooseFileSystemEntriesOptionsAccepts {
    description?: string | undefined;
    mimeTypes?: string[] | undefined;
    extensions?: string[] | undefined;
}

interface ChooseFileSystemEntriesFileOptions {
    accepts?: ChooseFileSystemEntriesOptionsAccepts[] | undefined;
    excludeAcceptAllOption?: boolean | undefined;
}

/**
 * @deprecated Old method just for Chromium <=85. Use `showOpenFilePicker()` in the new API.
 */
function chooseFileSystemEntries(
    options?: ChooseFileSystemEntriesFileOptions & {
        type?: 'open-file' | undefined;
        multiple?: false | undefined;
    },
): Promise<FileSystemFileHandle>;
/**
 * @deprecated Old method just for Chromium <=85. Use `showOpenFilePicker()` in the new API.
 */
function chooseFileSystemEntries(
    options: ChooseFileSystemEntriesFileOptions & {
        type?: 'open-file' | undefined;
        multiple: true;
    },
): Promise<FileSystemFileHandle[]>;
/**
 * @deprecated Old method just for Chromium <=85. Use `showSaveFilePicker()` in the new API.
 */
function chooseFileSystemEntries(
    options: ChooseFileSystemEntriesFileOptions & {
        type: 'save-file';
    },
): Promise<FileSystemFileHandle>;
/**
 * @deprecated Old method just for Chromium <=85. Use `showDirectoryPicker()` in the new API.
 */
function chooseFileSystemEntries(options: { type: 'open-directory' }): Promise<FileSystemDirectoryHandle>;

interface GetSystemDirectoryOptions {
    type: 'sandbox';
}

interface FileSystemDirectoryHandle {
    /**
     * @deprecated Old property just for Chromium <=85. Use `.getFileHandle()` in the new API.
     */
    getFile: FileSystemDirectoryHandle['getFileHandle'];

    /**
     * @deprecated Old property just for Chromium <=85. Use `.getDirectoryHandle()` in the new API.
     */
    getDirectory: FileSystemDirectoryHandle['getDirectoryHandle'];

    /**
     * @deprecated Old property just for Chromium <=85. Use `.keys()`, `.values()`, `.entries()`, or the directory itself as an async iterable in the new API.
     */
    getEntries: FileSystemDirectoryHandle['values'];
}

interface FileSystemHandlePermissionDescriptor {
    /**
     * @deprecated Old property just for Chromium <=85. Use `mode: ...` in the new API.
     */
    writable?: boolean | undefined;
}
}