import { FrontendApplicationContribution } from '@theia/core/lib/browser/frontend-application-contribution';
import { FrontendApplicationStateService } from '@theia/core/lib/browser/frontend-application-state';
import { StorageService } from '@theia/core/lib/browser/storage-service';
import {
  Command,
  CommandContribution,
  CommandRegistry,
  CommandService,
} from '@theia/core/lib/common/command';
import type { Disposable } from '@theia/core/lib/common/disposable';
import { Emitter } from '@theia/core/lib/common/event';
import { ILogger } from '@theia/core/lib/common/logger';
import { MessageService } from '@theia/core/lib/common/message-service';
import { nls } from '@theia/core/lib/common/nls';
import { deepClone } from '@theia/core/lib/common/objects';
import { Deferred } from '@theia/core/lib/common/promise-util';
import type { Mutable } from '@theia/core/lib/common/types';
import { inject, injectable, optional } from '@theia/core/shared/inversify';
import {
  OutputChannel,
  OutputChannelManager,
} from '@theia/output/lib/browser/output-channel';
import {
  BoardIdentifier,
  BoardUserField,
  BoardWithPackage,
  BoardsConfig,
  BoardsConfigChangeEvent,
  BoardsPackage,
  BoardsService,
  DetectedPorts,
  Port,
  PortIdentifier,
  boardIdentifierEquals,
  emptyBoardsConfig,
  isBoardIdentifier,
  isBoardIdentifierChangeEvent,
  isPortIdentifier,
  isPortIdentifierChangeEvent,
  portIdentifierEquals,
  sanitizeFqbn,
  serializePlatformIdentifier,
} from '../../common/protocol';
import {
  BoardList,
  BoardListHistory,
  EditBoardsConfigActionParams,
  SelectBoardsConfigActionParams,
  createBoardList,
  isBoardListHistory,
} from '../../common/protocol/board-list';
import type { Defined } from '../../common/types';
import type {
  StartupTask,
  StartupTaskProvider,
} from '../../electron-common/startup-task';
import { NotificationCenter } from '../notification-center';

const boardListHistoryStorageKey = 'arduino-ide:boardListHistory';
const selectedPortStorageKey = 'arduino-ide:selectedPort';
const selectedBoardStorageKey = 'arduino-ide:selectedBoard';

type UpdateBoardsConfigReason =
  /**
   * Restore previous state at IDE startup.
   */
  | 'restore'
  /**
   * The board and the optional port were changed from the dialog.
   */
  | 'dialog'
  /**
   * The board and the port were updated from the board select toolbar.
   */
  | 'toolbar'
  /**
   * The board and port configuration was inherited from another window.
   */
  | 'inherit';

interface RefreshBoardListParams {
  detectedPorts?: DetectedPorts;
  boardsConfig?: BoardsConfig;
  boardListHistory?: BoardListHistory;
}

export type UpdateBoardsConfigParams =
  | BoardIdentifier
  /**
   * `'unset-board'` is special case when a non installed board is selected (no FQBN), the platform is installed,
   * but there is no way to determine the FQBN from the previous partial data, and IDE2 unsets the board.
   */
  | 'unset-board'
  | PortIdentifier
  | (Readonly<Defined<BoardsConfig>> &
      Readonly<{ reason?: UpdateBoardsConfigReason }>);

type HistoryDidNotChange = undefined;
type HistoryDidDelete = Readonly<{ [portKey: string]: undefined }>;
type HistoryDidUpdate = Readonly<{ [portKey: string]: BoardIdentifier }>;
type BoardListHistoryUpdateResult =
  | HistoryDidNotChange
  | HistoryDidDelete
  | HistoryDidUpdate;

type BoardToSelect = BoardIdentifier | undefined | 'ignore-board';
type PortToSelect = PortIdentifier | undefined | 'ignore-port';

function sanitizeBoardToSelectFQBN(board: BoardToSelect): BoardToSelect {
  if (isBoardIdentifier(board)) {
    return sanitizeBoardIdentifierFQBN(board);
  }
  return board;
}
function sanitizeBoardIdentifierFQBN(board: BoardIdentifier): BoardIdentifier {
  if (board.fqbn) {
    const copy: Mutable<BoardIdentifier> = deepClone(board);
    copy.fqbn = sanitizeFqbn(board.fqbn);
    return copy;
  }
  return board;
}

interface UpdateBoardListHistoryParams {
  readonly portToSelect: PortToSelect;
  readonly boardToSelect: BoardToSelect;
}

interface UpdateBoardsDataParams {
  readonly boardToSelect: BoardToSelect;
  readonly reason?: UpdateBoardsConfigReason;
}

export interface SelectBoardsConfigAction {
  (params: SelectBoardsConfigActionParams): void;
}

export interface EditBoardsConfigAction {
  (params?: EditBoardsConfigActionParams): void;
}

export interface BoardListUIActions {
  /**
   * Sets the frontend's port and board configuration according to the params.
   */
  readonly select: SelectBoardsConfigAction;
  /**
   * Opens up the boards config dialog with the port and (optional) board to select in the dialog.
   * Calling this function does not immediately change the frontend's port and board config, but
   * preselects items in the dialog.
   */
  readonly edit: EditBoardsConfigAction;
}
export type BoardListUI = BoardList & BoardListUIActions;

export type BoardsConfigChangeEventUI = BoardsConfigChangeEvent &
  Readonly<{ reason?: UpdateBoardsConfigReason }>;

@injectable()
export class BoardListDumper implements Disposable {
  @inject(OutputChannelManager)
  private readonly outputChannelManager: OutputChannelManager;

  private outputChannel: OutputChannel | undefined;

  dump(boardList: BoardList): void {
    if (!this.outputChannel) {
      this.outputChannel = this.outputChannelManager.getChannel(
        'Developer (Arduino)'
      );
    }
    this.outputChannel.show({ preserveFocus: true });
    this.outputChannel.append(boardList.toString() + '\n');
  }

  dispose(): void {
    this.outputChannel?.dispose();
  }
}

@injectable()
export class BoardsServiceProvider
  implements
    FrontendApplicationContribution,
    StartupTaskProvider,
    CommandContribution
{
  @inject(ILogger)
  private readonly logger: ILogger;
  @inject(MessageService)
  private readonly messageService: MessageService;
  @inject(BoardsService)
  private readonly boardsService: BoardsService;
  @inject(CommandService)
  private readonly commandService: CommandService;
  @inject(StorageService)
  private readonly storageService: StorageService;
  @inject(NotificationCenter)
  private readonly notificationCenter: NotificationCenter;
  @inject(FrontendApplicationStateService)
  private readonly appStateService: FrontendApplicationStateService;
  @optional()
  @inject(BoardListDumper)
  private readonly boardListDumper?: BoardListDumper;

  private _boardsConfig = emptyBoardsConfig();
  private _detectedPorts: DetectedPorts = {};
  private _boardList = this.createBoardListUI(createBoardList({}));
  private _boardListHistory: Mutable<BoardListHistory> = {};
  private _ready = new Deferred<void>();

  private readonly boardsConfigDidChangeEmitter =
    new Emitter<BoardsConfigChangeEventUI>();
  readonly onBoardsConfigDidChange = this.boardsConfigDidChangeEmitter.event;

  private readonly boardListDidChangeEmitter = new Emitter<BoardListUI>();
  /**
   * Emits an event on board config (port or board) change, and when the discovery (`board list --watch`) detected any changes.
   */
  readonly onBoardListDidChange = this.boardListDidChangeEmitter.event;

  onStart(): void {
    this.notificationCenter.onDetectedPortsDidChange(({ detectedPorts }) =>
      this.refreshBoardList({ detectedPorts })
    );
    this.notificationCenter.onPlatformDidInstall((event) =>
      this.maybeUpdateSelectedBoard(event)
    );
    this.appStateService
      .reachedState('ready')
      .then(async () => {
        const [detectedPorts, storedState] = await Promise.all([
          this.boardsService.getDetectedPorts(),
          this.restoreState(),
        ]);
        const { selectedBoard, selectedPort, boardListHistory } = storedState;
        const options: RefreshBoardListParams = {
          boardListHistory,
          detectedPorts,
        };
        // If either the port or the board is set, restore it. Otherwise, do not restore nothing.
        // It might override the inherited boards config from the other window on File > New Sketch
        if (selectedBoard || selectedPort) {
          options.boardsConfig = { selectedBoard, selectedPort };
        }
        this.refreshBoardList(options);
        this._ready.resolve();
      })
      .finally(() => this._ready.resolve());
  }

  onStop(): void {
    this.boardListDumper?.dispose();
  }

  registerCommands(registry: CommandRegistry): void {
    registry.registerCommand(USE_INHERITED_CONFIG, {
      execute: (
        boardsConfig: BoardsConfig,
        boardListHistory: BoardListHistory
      ) => {
        if (boardListHistory) {
          this._boardListHistory = boardListHistory;
        }
        this.update({ boardsConfig }, 'inherit');
      },
    });
    if (this.boardListDumper) {
      registry.registerCommand(DUMP_BOARD_LIST, {
        execute: () => this.boardListDumper?.dump(this._boardList),
      });
    }
    registry.registerCommand(CLEAR_BOARD_LIST_HISTORY, {
      execute: () => {
        this.refreshBoardList({ boardListHistory: {} });
        this.setData(boardListHistoryStorageKey, undefined);
      },
    });
    registry.registerCommand(CLEAR_BOARDS_CONFIG, {
      execute: () => {
        this.refreshBoardList({ boardsConfig: emptyBoardsConfig() });
        Promise.all([
          this.setData(selectedPortStorageKey, undefined),
          this.setData(selectedBoardStorageKey, undefined),
        ]);
      },
    });
  }

  tasks(): StartupTask[] {
    return [
      {
        command: USE_INHERITED_CONFIG.id,
        args: [this._boardsConfig, this._boardListHistory],
      },
    ];
  }

  private refreshBoardList(params?: RefreshBoardListParams): void {
    if (params?.detectedPorts) {
      this._detectedPorts = params.detectedPorts;
    }
    if (params?.boardsConfig) {
      this._boardsConfig = params.boardsConfig;
    }
    if (params?.boardListHistory) {
      this._boardListHistory = params.boardListHistory;
    }
    const boardList = createBoardList(
      this._detectedPorts,
      this._boardsConfig,
      this._boardListHistory
    );
    this._boardList = this.createBoardListUI(boardList);
    this.boardListDidChangeEmitter.fire(this._boardList);
  }

  private createBoardListUI(boardList: BoardList): BoardListUI {
    return Object.assign(boardList, {
      select: this.onBoardsConfigSelect.bind(this),
      edit: this.onBoardsConfigEdit.bind(this),
    });
  }

  private onBoardsConfigSelect(params: SelectBoardsConfigActionParams): void {
    this.updateConfig({ ...params, reason: 'toolbar' });
  }

  private async onBoardsConfigEdit(
    params?: EditBoardsConfigActionParams
  ): Promise<void> {
    const boardsConfig = await this.commandService.executeCommand<
      BoardsConfig | undefined
    >('arduino-open-boards-dialog', params);
    if (boardsConfig) {
      this.update({ boardsConfig }, 'dialog');
    }
  }

  private update(
    params: RefreshBoardListParams,
    reason?: UpdateBoardsConfigReason
  ): void {
    const { boardsConfig } = params;
    if (!boardsConfig) {
      return;
    }
    const { selectedBoard, selectedPort } = boardsConfig;
    if (selectedBoard && selectedPort) {
      this.updateConfig({
        selectedBoard,
        selectedPort,
        reason,
      });
    } else if (selectedBoard) {
      this.updateConfig(selectedBoard);
    } else if (selectedPort) {
      this.updateConfig(selectedPort);
    }
  }

  updateConfig(params: UpdateBoardsConfigParams): boolean {
    const previousSelectedBoard = this._boardsConfig.selectedBoard;
    const previousSelectedPort = this._boardsConfig.selectedPort;
    const boardToSelect = this.getBoardToSelect(params);
    const portToSelect = this.getPortToSelect(params);
    const reason = this.getUpdateReason(params);

    const boardDidChange =
      boardToSelect !== 'ignore-board' &&
      !boardIdentifierEquals(boardToSelect, previousSelectedBoard);
    const portDidChange =
      portToSelect !== 'ignore-port' &&
      !portIdentifierEquals(portToSelect, previousSelectedPort);
    const boardDidChangeEvent = boardDidChange
      ? // The change event must always contain any custom board options. Hence the board to select is not sanitized.
        { selectedBoard: boardToSelect, previousSelectedBoard }
      : undefined;
    const portDidChangeEvent = portDidChange
      ? { selectedPort: portToSelect, previousSelectedPort }
      : undefined;

    let event: BoardsConfigChangeEvent | undefined = boardDidChangeEvent;
    if (portDidChangeEvent) {
      if (event) {
        event = {
          ...event,
          ...portDidChangeEvent,
        };
      } else {
        event = portDidChangeEvent;
      }
    }
    if (!event) {
      return false;
    }

    // unlike for the board change event, every persistent state must not contain custom board config options in the FQBN
    const sanitizedBoardToSelect = sanitizeBoardToSelectFQBN(boardToSelect);

    this.maybeUpdateBoardListHistory({
      portToSelect,
      boardToSelect: sanitizedBoardToSelect,
    });
    this.maybeUpdateBoardsData({
      boardToSelect: sanitizedBoardToSelect,
      reason,
    });

    if (isBoardIdentifierChangeEvent(event)) {
      this._boardsConfig.selectedBoard = event.selectedBoard
        ? sanitizeBoardIdentifierFQBN(event.selectedBoard)
        : event.selectedBoard;
    }
    if (isPortIdentifierChangeEvent(event)) {
      this._boardsConfig.selectedPort = event.selectedPort;
    }

    if (reason) {
      event = Object.assign(event, { reason });
    }

    this.boardsConfigDidChangeEmitter.fire(event);
    this.refreshBoardList();
    this.saveState();
    return true;
  }

  private getBoardToSelect(params: UpdateBoardsConfigParams): BoardToSelect {
    if (isPortIdentifier(params)) {
      return 'ignore-board';
    }
    if (params === 'unset-board') {
      return undefined;
    }
    return isBoardIdentifier(params) ? params : params.selectedBoard;
  }

  private getPortToSelect(
    params: UpdateBoardsConfigParams
  ): Exclude<PortToSelect, undefined> {
    if (isBoardIdentifier(params) || params === 'unset-board') {
      return 'ignore-port';
    }
    return isPortIdentifier(params) ? params : params.selectedPort;
  }

  private getUpdateReason(
    params: UpdateBoardsConfigParams
  ): UpdateBoardsConfigReason | undefined {
    if (
      isBoardIdentifier(params) ||
      isPortIdentifier(params) ||
      params === 'unset-board'
    ) {
      return undefined;
    }
    return params.reason;
  }

  get ready(): Promise<void> {
    return this._ready.promise;
  }

  get boardsConfig(): BoardsConfig {
    return this._boardsConfig;
  }

  get boardList(): BoardListUI {
    return this._boardList;
  }

  get detectedPorts(): DetectedPorts {
    return this._detectedPorts;
  }

  async searchBoards({
    query,
  }: {
    query?: string;
    cores?: string[];
  }): Promise<BoardWithPackage[]> {
    const boards = await this.boardsService.searchBoards({ query });
    return boards;
  }

  async selectedBoardUserFields(): Promise<BoardUserField[]> {
    if (!this._boardsConfig.selectedBoard) {
      return [];
    }
    const fqbn = this._boardsConfig.selectedBoard.fqbn;
    if (!fqbn) {
      return [];
    }
    // Protocol must be set to `default` when uploading without a port selected:
    // https://arduino.github.io/arduino-cli/dev/platform-specification/#sketch-upload-configuration
    const protocol = this._boardsConfig.selectedPort?.protocol || 'default';
    return await this.boardsService.getBoardUserFields({ fqbn, protocol });
  }

  private async maybeUpdateSelectedBoard(platformDidInstallEvent: {
    item: BoardsPackage;
  }): Promise<void> {
    const { selectedBoard } = this._boardsConfig;
    if (
      selectedBoard &&
      !selectedBoard.fqbn &&
      BoardWithPackage.is(selectedBoard)
    ) {
      const selectedBoardPlatformId = serializePlatformIdentifier(
        selectedBoard.packageId
      );
      if (selectedBoardPlatformId === platformDidInstallEvent.item.id) {
        const installedSelectedBoard = platformDidInstallEvent.item.boards.find(
          (board) => board.name === selectedBoard.name
        );
        // if the board can be found by its name after the install event select it. otherwise unselect it
        // historical hint: https://github.com/arduino/arduino-ide/blob/144df893d0dafec64a26565cf912a98f32572da9/arduino-ide-extension/src/browser/boards/boards-service-provider.ts#L289-L320
        this.updateConfig(
          installedSelectedBoard ? installedSelectedBoard : 'unset-board'
        );
        if (!installedSelectedBoard) {
          const yes = nls.localize('vscode/extensionsUtils/yes', 'Yes');
          const answer = await this.messageService.warn(
            nls.localize(
              'arduino/board/couldNotFindPreviouslySelected',
              "Could not find previously selected board '{0}' in installed platform '{1}'. Please manually reselect the board you want to use. Do you want to reselect it now?",
              selectedBoard.name,
              platformDidInstallEvent.item.name
            ),
            nls.localize('arduino/board/reselectLater', 'Reselect later'),
            yes
          );
          if (answer === yes) {
            this.onBoardsConfigEdit({
              query: selectedBoard.name,
              portToSelect: this._boardsConfig.selectedPort,
            });
          }
        }
      }
    }
  }

  private maybeUpdateBoardListHistory(
    params: UpdateBoardListHistoryParams
  ): BoardListHistoryUpdateResult {
    const { portToSelect, boardToSelect } = params;
    const selectedPort = isPortIdentifier(portToSelect)
      ? portToSelect
      : portToSelect === 'ignore-port'
      ? this._boardsConfig.selectedPort
      : undefined;
    const selectedBoard = isBoardIdentifier(boardToSelect)
      ? boardToSelect
      : boardToSelect === 'ignore-board'
      ? this._boardsConfig.selectedBoard
      : undefined;
    if (selectedBoard && selectedPort) {
      const match = this.boardList.items.find(
        (item) =>
          portIdentifierEquals(item.port, selectedPort) &&
          item.board &&
          boardIdentifierEquals(item.board, selectedBoard)
      );
      const portKey = Port.keyOf(selectedPort);
      if (match) {
        // When board `B` is detected on port `P` and saving `B` on `P`, remove the entry instead!
        delete this._boardListHistory[portKey];
      } else {
        this._boardListHistory[portKey] = selectedBoard;
      }
      if (match) {
        return { [portKey]: undefined };
      }
      return { [portKey]: selectedBoard };
    }
    return undefined;
  }

  private maybeUpdateBoardsData(params: UpdateBoardsDataParams): void {
    const { boardToSelect, reason } = params;
    if (
      boardToSelect &&
      boardToSelect !== 'ignore-board' &&
      boardToSelect.fqbn &&
      (reason === 'toolbar' || reason === 'inherit')
    ) {
      const [, , , ...rest] = boardToSelect.fqbn.split(':');
      if (rest.length) {
        // https://github.com/arduino/arduino-ide/pull/2113
        // TODO: save update data store if reason is toolbar and the FQBN has options
      }
    }
  }

  private async saveState(): Promise<void> {
    const { selectedBoard, selectedPort } = this.boardsConfig;
    await Promise.all([
      this.setData(
        selectedBoardStorageKey,
        selectedBoard ? JSON.stringify(selectedBoard) : undefined
      ),
      this.setData(
        selectedPortStorageKey,
        selectedPort ? JSON.stringify(selectedPort) : undefined
      ),
      this.setData(
        boardListHistoryStorageKey,
        JSON.stringify(this._boardListHistory)
      ),
    ]);
  }

  private async restoreState(): Promise<
    Readonly<BoardsConfig> & { boardListHistory: BoardListHistory | undefined }
  > {
    const [maybeSelectedBoard, maybeSelectedPort, maybeBoardHistory] =
      await Promise.all([
        this.getData<string>(selectedBoardStorageKey),
        this.getData<string>(selectedPortStorageKey),
        this.getData<string>(boardListHistoryStorageKey),
      ]);
    const selectedBoard = this.tryParse(maybeSelectedBoard, isBoardIdentifier);
    const selectedPort = this.tryParse(maybeSelectedPort, isPortIdentifier);
    const boardListHistory = this.tryParse(
      maybeBoardHistory,
      isBoardListHistory
    );
    return { selectedBoard, selectedPort, boardListHistory };
  }

  private tryParse<T>(
    raw: string | undefined,
    typeGuard: (object: unknown) => object is T
  ): T | undefined {
    if (!raw) {
      return undefined;
    }
    try {
      const object = JSON.parse(raw);
      if (typeGuard(object)) {
        return object;
      }
    } catch {
      this.logger.error(`Failed to parse raw: '${raw}'`);
    }
    return undefined;
  }

  private setData<T>(key: string, value: T): Promise<void> {
    return this.storageService.setData(key, value);
  }

  private getData<T>(key: string): Promise<T | undefined> {
    return this.storageService.getData(key);
  }
}

/**
 * It should be neither visible nor called from outside.
 *
 * This service creates a startup task with the current board config and
 * passes the task to the electron-main process so that the new window
 * can inherit the boards config state of this service.
 *
 * Note that the state is always set, but new windows might ignore it.
 * For example, the new window already has a valid boards config persisted to the local storage.
 */
const USE_INHERITED_CONFIG: Command = {
  id: 'arduino-use-inherited-boards-config',
};

const DUMP_BOARD_LIST: Command = {
  id: 'arduino-dump-board-list',
  label: nls.localize('arduino/developer/dumpBoardList', 'Dump the Board List'),
  category: 'Developer (Arduino)',
};

const CLEAR_BOARD_LIST_HISTORY: Command = {
  id: 'arduino-clear-board-list-history',
  label: nls.localize(
    'arduino/developer/clearBoardList',
    'Clear the Board List History'
  ),
  category: 'Developer (Arduino)',
};

const CLEAR_BOARDS_CONFIG: Command = {
  id: 'arduino-clear-boards-config',
  label: nls.localize(
    'arduino/developer/clearBoardsConfig',
    'Clear the Board and Port Selection'
  ),
  category: 'Developer (Arduino)',
};