/*
 * Copyright 2010-2020 Gildas Lormeau
 * contact : gildas.lormeau <at> gmail.com
 * 
 * This file is part of SingleFile.
 *
 *   The code in this file is free software: you can redistribute it and/or 
 *   modify it under the terms of the GNU Affero General Public License 
 *   (GNU AGPL) as published by the Free Software Foundation, either version 3
 *   of the License, or (at your option) any later version.
 * 
 *   The code in this file is distributed in the hope that it will be useful, 
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of 
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero 
 *   General Public License for more details.
 *
 *   As additional permission under GNU AGPL version 3 section 7, you may 
 *   distribute UNMODIFIED VERSIONS OF THIS file without the copy of the GNU 
 *   AGPL normally required by section 4, provided you include this license 
 *   notice and a URL through which recipients can access the Corresponding 
 *   Source.
 */

/* global browser, Blob, URL, document */

import * as config from "./config.js";
import * as bookmarks from "./bookmarks.js";
import * as business from "./business.js";
import * as editor from "./editor.js";
import * as tabs from "./tabs.js";
import * as ui from "./../../ui/bg/index.js";
import * as woleet from "./../../lib/woleet/woleet.js";
import { GDrive } from "./../../lib/gdrive/gdrive.js";

const partialContents = new Map();
const MIMETYPE_HTML = "text/html";
const STATE_DOWNLOAD_COMPLETE = "complete";
const STATE_DOWNLOAD_INTERRUPTED = "interrupted";
const STATE_ERROR_CANCELED_CHROMIUM = "USER_CANCELED";
const ERROR_DOWNLOAD_CANCELED_GECKO = "canceled";
const ERROR_CONFLICT_ACTION_GECKO = "conflictaction prompt not yet implemented";
const ERROR_INCOGNITO_GECKO = "'incognito'";
const ERROR_INCOGNITO_GECKO_ALT = "\"incognito\"";
const ERROR_INVALID_FILENAME_GECKO = "illegal characters";
const ERROR_INVALID_FILENAME_CHROMIUM = "invalid filename";
const CLIENT_ID = "207618107333-3pj2pmelhnl4sf3rpctghs9cean3q8nj.apps.googleusercontent.com";
const SCOPES = ["https://www.googleapis.com/auth/drive.file"];
const CONFLICT_ACTION_SKIP = "skip";
const CONFLICT_ACTION_UNIQUIFY = "uniquify";
const REGEXP_ESCAPE = /([{}()^$&.*?/+|[\\\\]|\]|-)/g;

const manifest = browser.runtime.getManifest();
const requestPermissionIdentity = manifest.optional_permissions && manifest.optional_permissions.includes("identity");
const gDrive = new GDrive(CLIENT_ID, SCOPES);
export {
	onMessage,
	download,
	downloadPage,
	uploadPage
};

async function onMessage(message, sender) {
	if (message.method.endsWith(".download")) {
		return downloadTabPage(message, sender.tab);
	}
	if (message.method.endsWith(".disableGDrive")) {
		const authInfo = await config.getAuthInfo();
		config.removeAuthInfo();
		await gDrive.revokeAuthToken(authInfo && (authInfo.accessToken || authInfo.revokableAccessToken));
		return {};
	}
	if (message.method.endsWith(".end")) {
		if (message.hash) {
			await woleet.anchor(message.hash);
		}
		business.onSaveEnd(message.taskId);
		return {};
	}
	if (message.method.endsWith(".getInfo")) {
		return business.getTasksInfo();
	}
	if (message.method.endsWith(".cancel")) {
		business.cancelTask(message.taskId);
		return {};
	}
	if (message.method.endsWith(".cancelAll")) {
		business.cancelAllTasks();
		return {};
	}
	if (message.method.endsWith(".saveUrls")) {
		business.saveUrls(message.urls);
		return {};
	}
}

async function downloadTabPage(message, tab) {
	let contents;
	if (message.truncated) {
		contents = partialContents.get(tab.id);
		if (!contents) {
			contents = [];
			partialContents.set(tab.id, contents);
		}
		contents.push(message.content);
		if (message.finished) {
			partialContents.delete(tab.id);
		}
	} else if (message.content) {
		contents = [message.content];
	}
	if (!message.truncated || message.finished) {
		if (message.openEditor) {
			ui.onEdit(tab.id);
			await editor.open({ tabIndex: tab.index + 1, filename: message.filename, content: contents.join("") }, {
				backgroundSave: message.backgroundSave,
				saveToClipboard: message.saveToClipboard,
				saveToGDrive: message.saveToGDrive,
				confirmFilename: message.confirmFilename,
				incognito: tab.incognito,
				filenameConflictAction: message.filenameConflictAction,
				filenameReplacementCharacter: message.filenameReplacementCharacter,
				compressHTML: message.compressHTML,
				bookmarkId: message.bookmarkId,
				replaceBookmarkURL: message.replaceBookmarkURL,
				applySystemTheme: message.applySystemTheme,
				defaultEditorMode: message.defaultEditorMode,
				includeInfobar: message.includeInfobar,
				warnUnsavedPage: message.warnUnsavedPage
			});
		} else {
			if (message.saveToClipboard) {
				message.content = contents.join("");
				saveToClipboard(message);
				ui.onEnd(tab.id);
			} else {
				await downloadBlob(new Blob([contents], { type: MIMETYPE_HTML }), tab.id, tab.incognito, message);
			}
		}
	}
	return {};
}

async function downloadBlob(blob, tabId, incognito, message) {
	try {
		if (message.saveToGDrive) {
			await uploadPage(message.taskId, message.filename, blob, {
				forceWebAuthFlow: message.forceWebAuthFlow,
				extractAuthCode: message.extractAuthCode
			}, {
				onProgress: (offset, size) => ui.onUploadProgress(tabId, offset, size)
			});
		} else {
			message.url = URL.createObjectURL(blob);
			await downloadPage(message, {
				confirmFilename: message.confirmFilename,
				incognito,
				filenameConflictAction: message.filenameConflictAction,
				filenameReplacementCharacter: message.filenameReplacementCharacter,
				includeInfobar: message.includeInfobar
			});
		}
		ui.onEnd(tabId);
	} catch (error) {
		if (!error.message || error.message != "upload_cancelled") {
			console.error(error); // eslint-disable-line no-console
			ui.onError(tabId);
		}
	} finally {
		if (message.url) {
			URL.revokeObjectURL(message.url);
		}
	}
}

function getRegExp(string) {
	return string.replace(REGEXP_ESCAPE, "\\$1");
}

async function getAuthInfo(authOptions, force) {
	let authInfo = await config.getAuthInfo();
	const options = {
		interactive: true,
		auto: authOptions.extractAuthCode,
		forceWebAuthFlow: authOptions.forceWebAuthFlow,
		requestPermissionIdentity,
		launchWebAuthFlow: options => tabs.launchWebAuthFlow(options),
		extractAuthCode: authURL => tabs.extractAuthCode(authURL),
		promptAuthCode: () => tabs.promptValue("Please enter the access code for Google Drive")
	};
	gDrive.setAuthInfo(authInfo, options);
	if (!authInfo || !authInfo.accessToken || force) {
		authInfo = await gDrive.auth(options);
		if (authInfo) {
			await config.setAuthInfo(authInfo);
		} else {
			await config.removeAuthInfo();
		}
	}
	return authInfo;
}

async function uploadPage(taskId, filename, blob, authOptions, uploadOptions) {
	try {
		await getAuthInfo(authOptions);
		const taskInfo = business.getTaskInfo(taskId);
		if (taskInfo && !taskInfo.cancelled) {
			const uploadInfo = await gDrive.upload(filename, blob, uploadOptions);
			business.setCancelCallback(taskId, uploadInfo.cancelUpload);
			return await uploadInfo.uploadPromise;
		}
	}
	catch (error) {
		if (error.message == "invalid_token") {
			let authInfo;
			try {
				authInfo = await gDrive.refreshAuthToken();
			} catch (error) {
				if (error.message == "unknown_token") {
					authInfo = await getAuthInfo(authOptions, true);
				} else {
					throw error;
				}
			}
			if (authInfo) {
				await config.setAuthInfo(authInfo);
			} else {
				await config.removeAuthInfo();
			}
			await uploadPage(taskId, filename, blob, authOptions, uploadOptions);
		} else {
			throw error;
		}
	}
}

async function downloadPage(pageData, options) {
	const filenameConflictAction = options.filenameConflictAction;
	let skipped;
	if (filenameConflictAction == CONFLICT_ACTION_SKIP) {
		const downloadItems = await browser.downloads.search({
			filenameRegex: "(\\\\|/)" + getRegExp(pageData.filename) + "$",
			exists: true
		});
		if (downloadItems.length) {
			skipped = true;
		} else {
			options.filenameConflictAction = CONFLICT_ACTION_UNIQUIFY;
		}
	}
	if (!skipped) {
		const downloadInfo = {
			url: pageData.url,
			saveAs: options.confirmFilename,
			filename: pageData.filename,
			conflictAction: options.filenameConflictAction
		};
		if (options.incognito) {
			downloadInfo.incognito = true;
		}
		const downloadData = await download(downloadInfo, options.filenameReplacementCharacter);
		if (downloadData.filename && pageData.bookmarkId && pageData.replaceBookmarkURL) {
			if (!downloadData.filename.startsWith("file:")) {
				if (downloadData.filename.startsWith("/")) {
					downloadData.filename = downloadData.filename.substring(1);
				}
				downloadData.filename = "file:///" + downloadData.filename;
			}
			await bookmarks.update(pageData.bookmarkId, { url: downloadData.filename });
		}
	}
}

async function download(downloadInfo, replacementCharacter) {
	let downloadId;
	try {
		downloadId = await browser.downloads.download(downloadInfo);
	} catch (error) {
		if (error.message) {
			const errorMessage = error.message.toLowerCase();
			const invalidFilename = errorMessage.includes(ERROR_INVALID_FILENAME_GECKO) || errorMessage.includes(ERROR_INVALID_FILENAME_CHROMIUM);
			if (invalidFilename && downloadInfo.filename.startsWith(".")) {
				downloadInfo.filename = replacementCharacter + downloadInfo.filename;
				return download(downloadInfo, replacementCharacter);
			} else if (invalidFilename && downloadInfo.filename.includes(",")) {
				downloadInfo.filename = downloadInfo.filename.replace(/,/g, replacementCharacter);
				return download(downloadInfo, replacementCharacter);
			} else if (invalidFilename && !downloadInfo.filename.match(/^[\x00-\x7F]+$/)) { // eslint-disable-line  no-control-regex
				downloadInfo.filename = downloadInfo.filename.replace(/[^\x00-\x7F]+/g, replacementCharacter); // eslint-disable-line  no-control-regex
				return download(downloadInfo, replacementCharacter);
			} else if ((errorMessage.includes(ERROR_INCOGNITO_GECKO) || errorMessage.includes(ERROR_INCOGNITO_GECKO_ALT)) && downloadInfo.incognito) {
				delete downloadInfo.incognito;
				return download(downloadInfo, replacementCharacter);
			} else if (errorMessage == ERROR_CONFLICT_ACTION_GECKO && downloadInfo.conflictAction) {
				delete downloadInfo.conflictAction;
				return download(downloadInfo, replacementCharacter);
			} else if (errorMessage.includes(ERROR_DOWNLOAD_CANCELED_GECKO)) {
				return {};
			} else {
				throw error;
			}
		} else {
			throw error;
		}
	}
	return new Promise((resolve, reject) => {
		browser.downloads.onChanged.addListener(onChanged);

		function onChanged(event) {
			if (event.id == downloadId && event.state) {
				if (event.state.current == STATE_DOWNLOAD_COMPLETE) {
					browser.downloads.search({ id: downloadId })
						.then(downloadItems => resolve({ filename: downloadItems[0] && downloadItems[0].filename }))
						.catch(() => resolve({}));
					browser.downloads.onChanged.removeListener(onChanged);
				}
				if (event.state.current == STATE_DOWNLOAD_INTERRUPTED) {
					if (event.error && event.error.current == STATE_ERROR_CANCELED_CHROMIUM) {
						resolve({});
					} else {
						reject(new Error(event.state.current));
					}
					browser.downloads.onChanged.removeListener(onChanged);
				}
			}
		}
	});
}

function saveToClipboard(pageData) {
	const command = "copy";
	document.addEventListener(command, listener);
	document.execCommand(command);
	document.removeEventListener(command, listener);

	function listener(event) {
		event.clipboardData.setData(MIMETYPE_HTML, pageData.content);
		event.clipboardData.setData("text/plain", pageData.content);
		event.preventDefault();
	}
}