import { SendData } from '../models/data/sendData';

import { SendRequest } from '../models/request/sendRequest';

import { ErrorResponse } from '../models/response/errorResponse';
import { SendResponse } from '../models/response/sendResponse';

import { EncArrayBuffer } from '../models/domain/encArrayBuffer';
import { EncString } from '../models/domain/encString';
import { Send } from '../models/domain/send';
import { SendFile } from '../models/domain/sendFile';
import { SendText } from '../models/domain/sendText';
import { SymmetricCryptoKey } from '../models/domain/symmetricCryptoKey';

import { FileUploadType } from '../enums/fileUploadType';
import { SendType } from '../enums/sendType';

import { SendView } from '../models/view/sendView';

import { ApiService } from '../abstractions/api.service';
import { CryptoService } from '../abstractions/crypto.service';
import { CryptoFunctionService } from '../abstractions/cryptoFunction.service';
import { FileUploadService } from '../abstractions/fileUpload.service';
import { I18nService } from '../abstractions/i18n.service';
import { SendService as SendServiceAbstraction } from '../abstractions/send.service';
import { StorageService } from '../abstractions/storage.service';
import { UserService } from '../abstractions/user.service';

import { Utils } from '../misc/utils';

const Keys = {
    sendsPrefix: 'sends_',
};

export class SendService implements SendServiceAbstraction {
    decryptedSendCache: SendView[];

    constructor(private cryptoService: CryptoService, private userService: UserService,
        private apiService: ApiService, private fileUploadService: FileUploadService,
        private storageService: StorageService, private i18nService: I18nService,
        private cryptoFunctionService: CryptoFunctionService) { }

    clearCache(): void {
        this.decryptedSendCache = null;
    }

    async encrypt(model: SendView, file: File | ArrayBuffer, password: string,
        key?: SymmetricCryptoKey): Promise<[Send, EncArrayBuffer]> {
        let fileData: EncArrayBuffer = null;
        const send = new Send();
        send.id = model.id;
        send.type = model.type;
        send.disabled = model.disabled;
        send.hideEmail = model.hideEmail;
        send.maxAccessCount = model.maxAccessCount;
        if (model.key == null) {
            model.key = await this.cryptoFunctionService.randomBytes(16);
            model.cryptoKey = await this.cryptoService.makeSendKey(model.key);
        }
        if (password != null) {
            const passwordHash = await this.cryptoFunctionService.pbkdf2(password, model.key, 'sha256', 100000);
            send.password = Utils.fromBufferToB64(passwordHash);
        }
        send.key = await this.cryptoService.encrypt(model.key, key);
        send.name = await this.cryptoService.encrypt(model.name, model.cryptoKey);
        send.notes = await this.cryptoService.encrypt(model.notes, model.cryptoKey);
        if (send.type === SendType.Text) {
            send.text = new SendText();
            send.text.text = await this.cryptoService.encrypt(model.text.text, model.cryptoKey);
            send.text.hidden = model.text.hidden;
        } else if (send.type === SendType.File) {
            send.file = new SendFile();
            if (file != null) {
                if (file instanceof ArrayBuffer) {
                    const [name, data] = await this.encryptFileData(model.file.fileName, file, model.cryptoKey);
                    send.file.fileName = name;
                    fileData = data;
                } else {
                    fileData = await this.parseFile(send, file, model.cryptoKey);
                }
            }
        }

        return [send, fileData];
    }

    async get(id: string): Promise<Send> {
        const userId = await this.userService.getUserId();
        const sends = await this.storageService.get<{ [id: string]: SendData; }>(
            Keys.sendsPrefix + userId);
        if (sends == null || !sends.hasOwnProperty(id)) {
            return null;
        }

        return new Send(sends[id]);
    }

    async getAll(): Promise<Send[]> {
        const userId = await this.userService.getUserId();
        const sends = await this.storageService.get<{ [id: string]: SendData; }>(
            Keys.sendsPrefix + userId);
        const response: Send[] = [];
        for (const id in sends) {
            if (sends.hasOwnProperty(id)) {
                response.push(new Send(sends[id]));
            }
        }
        return response;
    }

    async getAllDecrypted(): Promise<SendView[]> {
        if (this.decryptedSendCache != null) {
            return this.decryptedSendCache;
        }

        const hasKey = await this.cryptoService.hasKey();
        if (!hasKey) {
            throw new Error('No key.');
        }

        const decSends: SendView[] = [];
        const promises: Promise<any>[] = [];
        const sends = await this.getAll();
        sends.forEach(send => {
            promises.push(send.decrypt().then(f => decSends.push(f)));
        });

        await Promise.all(promises);
        decSends.sort(Utils.getSortFunction(this.i18nService, 'name'));

        this.decryptedSendCache = decSends;
        return this.decryptedSendCache;
    }

    async saveWithServer(sendData: [Send, EncArrayBuffer]): Promise<any> {
        const request = new SendRequest(sendData[0], sendData[1]?.buffer.byteLength);
        let response: SendResponse;
        if (sendData[0].id == null) {
            if (sendData[0].type === SendType.Text) {
                response = await this.apiService.postSend(request);
            } else {
                try {
                    const uploadDataResponse = await this.apiService.postFileTypeSend(request);
                    response = uploadDataResponse.sendResponse;

                    await this.fileUploadService.uploadSendFile(uploadDataResponse, sendData[0].file.fileName, sendData[1]);
                } catch (e) {
                    if (e instanceof ErrorResponse && (e as ErrorResponse).statusCode === 404) {
                        response = await this.legacyServerSendFileUpload(sendData, request);
                    } else if (e instanceof ErrorResponse) {
                        throw new Error((e as ErrorResponse).getSingleMessage());
                    } else {
                        throw e;
                    }
                }
            }
            sendData[0].id = response.id;
            sendData[0].accessId = response.accessId;
        } else {
            response = await this.apiService.putSend(sendData[0].id, request);
        }

        const userId = await this.userService.getUserId();
        const data = new SendData(response, userId);
        await this.upsert(data);
    }

    /**
     * @deprecated Mar 25 2021: This method has been deprecated in favor of direct uploads.
     * This method still exists for backward compatibility with old server versions.
     */
    async legacyServerSendFileUpload(sendData: [Send, EncArrayBuffer], request: SendRequest): Promise<SendResponse>
    {
        const fd = new FormData();
        try {
            const blob = new Blob([sendData[1].buffer], { type: 'application/octet-stream' });
            fd.append('model', JSON.stringify(request));
            fd.append('data', blob, sendData[0].file.fileName.encryptedString);
        } catch (e) {
            if (Utils.isNode && !Utils.isBrowser) {
                fd.append('model', JSON.stringify(request));
                fd.append('data', Buffer.from(sendData[1].buffer) as any, {
                    filepath: sendData[0].file.fileName.encryptedString,
                    contentType: 'application/octet-stream',
                } as any);
            } else {
                throw e;
            }
        }
        return await this.apiService.postSendFileLegacy(fd);
    }

    async upsert(send: SendData | SendData[]): Promise<any> {
        const userId = await this.userService.getUserId();
        let sends = await this.storageService.get<{ [id: string]: SendData; }>(
            Keys.sendsPrefix + userId);
        if (sends == null) {
            sends = {};
        }

        if (send instanceof SendData) {
            const s = send as SendData;
            sends[s.id] = s;
        } else {
            (send as SendData[]).forEach(s => {
                sends[s.id] = s;
            });
        }

        await this.storageService.save(Keys.sendsPrefix + userId, sends);
        this.decryptedSendCache = null;
    }

    async replace(sends: { [id: string]: SendData; }): Promise<any> {
        const userId = await this.userService.getUserId();
        await this.storageService.save(Keys.sendsPrefix + userId, sends);
        this.decryptedSendCache = null;
    }

    async clear(userId: string): Promise<any> {
        await this.storageService.remove(Keys.sendsPrefix + userId);
        this.decryptedSendCache = null;
    }

    async delete(id: string | string[]): Promise<any> {
        const userId = await this.userService.getUserId();
        const sends = await this.storageService.get<{ [id: string]: SendData; }>(
            Keys.sendsPrefix + userId);
        if (sends == null) {
            return;
        }

        if (typeof id === 'string') {
            if (sends[id] == null) {
                return;
            }
            delete sends[id];
        } else {
            (id as string[]).forEach(i => {
                delete sends[i];
            });
        }

        await this.storageService.save(Keys.sendsPrefix + userId, sends);
        this.decryptedSendCache = null;
    }

    async deleteWithServer(id: string): Promise<any> {
        await this.apiService.deleteSend(id);
        await this.delete(id);
    }

    async removePasswordWithServer(id: string): Promise<any> {
        const response = await this.apiService.putSendRemovePassword(id);
        const userId = await this.userService.getUserId();
        const data = new SendData(response, userId);
        await this.upsert(data);
    }

    private parseFile(send: Send, file: File, key: SymmetricCryptoKey): Promise<EncArrayBuffer> {
        return new Promise((resolve, reject) => {
            const reader = new FileReader();
            reader.readAsArrayBuffer(file);
            reader.onload = async evt => {
                try {
                    const [name, data] = await this.encryptFileData(file.name, evt.target.result as ArrayBuffer, key);
                    send.file.fileName = name;
                    resolve(data);
                } catch (e) {
                    reject(e);
                }
            };
            reader.onerror = evt => {
                reject('Error reading file.');
            };
        });
    }

    private async encryptFileData(fileName: string, data: ArrayBuffer,
        key: SymmetricCryptoKey): Promise<[EncString, EncArrayBuffer]> {
        const encFileName = await this.cryptoService.encrypt(fileName, key);
        const encFileData = await this.cryptoService.encryptToBytes(data, key);
        return [encFileName, encFileData];
    }
}