import { FSWatcher, watch } from "chokidar";
import { EventEmitter } from "events";
import { join } from "path";
import { DocumentAccessor } from "../../model/doc";
import { DiffWatcherEvent, IDiffWatcher } from "../watcher";
import { setupHelp, setupRecursive } from "./util";

type RecursiveWatcherOption = {
    /** @default true */
    watchFile?: boolean;
    /** @default false */
    watchDir?: boolean;
};

export class RecursiveWatcher extends EventEmitter implements IDiffWatcher {
    on<U extends keyof DiffWatcherEvent>(event: U, listener: DiffWatcherEvent[U]): this {
        return super.on(event, listener);
    }
    emit<U extends keyof DiffWatcherEvent>(event: U, ...arg: Parameters<DiffWatcherEvent[U]>): boolean {
        return super.emit(event, ...arg);
    }
    readonly path: string;
    private watcher: FSWatcher;

    constructor(path: string, option: RecursiveWatcherOption = {
        watchDir: false,
        watchFile: true,
    }) {
        super();
        this.path = path;
        this.watcher = watch(path, {
            persistent: true,
            ignoreInitial: true,
            depth: 100,
        });
        option.watchFile ??= true;
        if (option.watchFile) {
            this.watcher.on("add", path => {
                const cpath = path;
                // console.log("add ", cpath);
                this.emit("create", cpath);
            }).on("unlink", path => {
                const cpath = path;
                // console.log("unlink ", cpath);
                this.emit("delete", cpath);
            });
        }
        if (option.watchDir) {
            this.watcher.on("addDir", path => {
                const cpath = path;
                this.emit("create", cpath);
            }).on("unlinkDir", path => {
                const cpath = path;
                this.emit("delete", cpath);
            });
        }
    }
    async setup(cntr: DocumentAccessor): Promise<void> {
        await setupRecursive(this, this.path, cntr);
    }
}