// Copyright (C) The Arvados Authors. All rights reserved.
//
// SPDX-License-Identifier: AGPL-3.0

import { CommonResourceService } from "../../common/api/common-resource-service";
import { CollectionResource } from "../../models/collection";
import axios, { AxiosInstance } from "axios";
import { KeepService } from "../keep-service/keep-service";
import { FilterBuilder } from "../../common/api/filter-builder";
import { CollectionFile, createCollectionFile, createCollectionDirectory, createCollectionFilesTree, CollectionFileType, CollectionDirectory } from "../../models/collection-file";
import { parseKeepManifestText, stringifyKeepManifest } from "../collection-files-service/collection-manifest-parser";
import * as _ from "lodash";
import { KeepManifestStream } from "../../models/keep-manifest";
import { WebDAV } from "../../common/webdav";
import { AuthService } from "../auth-service/auth-service";
import { mapTree, getNodeChildren, getNode, TreeNode } from "../../models/tree";

export type UploadProgress = (fileId: number, loaded: number, total: number, currentTime: number) => void;

export class CollectionService extends CommonResourceService<CollectionResource> {
    constructor(serverApi: AxiosInstance, private keepService: KeepService, private webdavClient: WebDAV, private authService: AuthService) {
        super(serverApi, "collections");
    }

    async files(uuid: string) {
        const request = await this.webdavClient.propfind(`/c=${uuid}`);
        if (request.responseXML != null) {
            const files = this.extractFilesData(request.responseXML);
            const tree = createCollectionFilesTree(files);
            const sortedTree = mapTree(node => {
                const children = getNodeChildren(node.id)(tree).map(id => getNode(id)(tree)) as TreeNode<CollectionDirectory | CollectionFile>[];
                children.sort((a, b) =>
                    a.value.type !== b.value.type
                        ? a.value.type === CollectionFileType.DIRECTORY ? -1 : 1
                        : a.value.name.localeCompare(b.value.name)
                );
                return { ...node, children: children.map(child => child.id) };
            })(tree);
            return sortedTree;
        }
        return Promise.reject();
    }

    async deleteFile(collectionUuid: string, filePath: string) {
        return this.webdavClient.delete(`/c=${collectionUuid}${filePath}`);
    }

    extractFilesData(document: Document) {
        return Array
            .from(document.getElementsByTagName('D:response'))
            .slice(1)
            .map(element => {
                const [displayNameElement] = Array.from(element.getElementsByTagName('D:displayname'));
                const name = displayNameElement ? displayNameElement.innerHTML : undefined;

                const [sizeElement] = Array.from(element.getElementsByTagName('D:getcontentlength'));
                const size = sizeElement ? parseInt(sizeElement.innerHTML, 10) : 0;

                const [hrefElement] = Array.from(element.getElementsByTagName('D:href'));
                const pathname = hrefElement ? hrefElement.innerHTML : undefined;
                const directory = pathname && pathname.replace(/\/c=[0-9a-zA-Z\-]*/, '').replace(`/${name || ''}`, '');

                const href = this.webdavClient.defaults.baseURL + pathname + '?api_token=' + this.authService.getApiToken();

                const data = {
                    url: href,
                    id: `${directory}/${name}`,
                    name,
                    path: directory,
                };

                const [resourceTypeElement] = Array.from(element.getElementsByTagName('D:resourcetype'));
                return resourceTypeElement && resourceTypeElement.innerHTML === ''
                    ? createCollectionFile({ ...data, size })
                    : createCollectionDirectory(data);

            });
    }


    private readFile(file: File): Promise<ArrayBuffer> {
        return new Promise<ArrayBuffer>(resolve => {
            const reader = new FileReader();
            reader.onload = () => {
                resolve(reader.result as ArrayBuffer);
            };

            reader.readAsArrayBuffer(file);
        });
    }

    private uploadFile(keepServiceHost: string, file: File, fileId: number, onProgress?: UploadProgress): Promise<CollectionFile> {
        return this.readFile(file).then(content => {
            return axios.post<string>(keepServiceHost, content, {
                headers: {
                    'Content-Type': 'text/octet-stream'
                },
                onUploadProgress: (e: ProgressEvent) => {
                    if (onProgress) {
                        onProgress(fileId, e.loaded, e.total, Date.now());
                    }
                    console.log(`${e.loaded} / ${e.total}`);
                }
            }).then(data => createCollectionFile({
                id: data.data,
                name: file.name,
                size: file.size
            }));
        });
    }

    private async updateManifest(collectionUuid: string, files: CollectionFile[]): Promise<CollectionResource> {
        const collection = await this.get(collectionUuid);
        const manifest: KeepManifestStream[] = parseKeepManifestText(collection.manifestText);

        files.forEach(f => {
            let kms = manifest.find(stream => stream.name === f.path);
            if (!kms) {
                kms = {
                    files: [],
                    locators: [],
                    name: f.path
                };
                manifest.push(kms);
            }
            kms.locators.push(f.id);
            const len = kms.files.length;
            const nextPos = len > 0
                ? parseInt(kms.files[len - 1].position, 10) + kms.files[len - 1].size
                : 0;
            kms.files.push({
                name: f.name,
                position: nextPos.toString(),
                size: f.size
            });
        });

        console.log(manifest);

        const manifestText = stringifyKeepManifest(manifest);
        const data = { ...collection, manifestText };
        return this.update(collectionUuid, CommonResourceService.mapKeys(_.snakeCase)(data));
    }

    uploadFiles(collectionUuid: string, files: File[], onProgress?: UploadProgress): Promise<CollectionResource | never> {
        const filters = FilterBuilder.create()
            .addEqual("service_type", "proxy");

        return this.keepService.list({ filters }).then(data => {
            if (data.items && data.items.length > 0) {
                const serviceHost =
                    (data.items[0].serviceSslFlag ? "https://" : "http://") +
                    data.items[0].serviceHost +
                    ":" + data.items[0].servicePort;

                console.log("serviceHost", serviceHost);

                const files$ = files.map((f, idx) => this.uploadFile(serviceHost, f, idx, onProgress));
                return Promise.all(files$).then(values => {
                    return this.updateManifest(collectionUuid, values);
                });
            } else {
                return Promise.reject("Missing keep service host");
            }
        });
    }
}