import formidable from 'formidable';
import { ClientUtils } from '../ClientUtils';
import { Utils } from '../Utils';
import { Upload } from '../server/SharedMediaTypes';

/**
 * Networking is repsonsible for connecting the client to the server. Networking
 * mainly provides methods that the client can use to begin the process of
 * interacting with the server, such as fetching or uploading files.
 */

export namespace Networking {
    export async function FetchFromServer(relativeRoute: string) {
        return (await fetch(relativeRoute)).text();
    }

    export function PostToServer(relativeRoute: string, body?: unknown) {
        return fetch(ClientUtils.prepend(relativeRoute), {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json',
            },
            body: body ? JSON.stringify(body) : undefined,
        }).then(response => {
            if (response.ok) return response.json() as object;

            return response.text().then(text => ({ error: '' + response.status + ':' + response.statusText + '-' + text }));
        });
    }

    /**
     * FileGuidPair attaches a guid to a file that is being uploaded,
     * allowing the client to track the upload progress.
     *
     * When files are dragged to the canvas, the overWriteDoc's ID is
     * used as the guid. Otherwise, a new guid is generated.
     */
    export interface FileGuidPair {
        file: File | Blob;
        guid?: string;
    }
    /**
     * Handles uploading basic file types to server and makes the API call to "/uploadFormData" endpoint
     * with the mapping of guid to files as parameters.
     *
     * @param fileguidpairs the files and corresponding guids to be uploaded to the server
     * @param browndash whether the endpoint should be invoked on the browndash server
     * @returns the response as a json from the server
     */
    export async function UploadFilesToServer<T extends Upload.FileInformation = Upload.FileInformation>(fileguidpairs: FileGuidPair | FileGuidPair[], browndash?: boolean): Promise<Upload.FileResponse<T>[]> {
        const formData = new FormData();
        if (Array.isArray(fileguidpairs)) {
            if (!fileguidpairs.length) {
                return [];
            }
            const maxFileSize = 50000000;
            if (fileguidpairs.some(f => f.file.size > maxFileSize)) {
                return new Promise<Upload.FileResponse<T>[]>(res => res([{ source: { newFilename: '', mimetype: '' } as formidable.File, result: new Error(`max file size (${maxFileSize / 1000000}MB) exceeded`) }]));
            }
            formData.set('fileguids', fileguidpairs.map(pair => pair.guid).join(';'));
            formData.set('filesize', fileguidpairs.reduce((sum, pair) => sum + pair.file.size, 0).toString());
            // If the fileguidpair has a guid to use (From the overwriteDoc) use that guid. Otherwise, generate a new guid.
            fileguidpairs.forEach(fileguidpair => formData.append(fileguidpair.guid ?? Utils.GenerateGuid(), fileguidpair.file));
        } else {
            // Handle the case where fileguidpairs is a single file.
            const guids = fileguidpairs.guid ?? Utils.GenerateGuid();
            formData.set('fileguids', guids);
            formData.set('filesize', fileguidpairs.file.size.toString());
            formData.append(guids, fileguidpairs.file);
        }
        const parameters = {
            method: 'POST',
            body: formData,
        };

        const endpoint = browndash ? '[insert endpoint allowing local => browndash]' : '/uploadFormData';
        const response = await fetch(endpoint, parameters);
        return response.json().then((json: Upload.FileResponse<T>[]) =>
            json.map(fileresponse => {
                if ('message' in fileresponse.result) fileresponse.result = new Error(fileresponse.result.message);
                return fileresponse;
            })
        );
    }

    export async function UploadYoutubeToServer<T extends Upload.FileInformation = Upload.FileInformation>(videoId: string, overwriteId?: string): Promise<Upload.FileResponse<T>[]> {
        const parameters = {
            method: 'POST',
            body: JSON.stringify({ videoId, overwriteId }),
            json: true,
        };
        const response = await fetch('/uploadYoutubeVideo', parameters);
        return response.json();
    }
    export async function QueryYoutubeProgress(videoId: string): Promise<{ progress: string }> {
        const parameters = {
            method: 'POST',
            body: JSON.stringify({ videoId }),
            json: true,
        };
        const response = await fetch('/queryYoutubeProgress', parameters);
        return response.json();
    }
}