const { ltrimSlashes } = require('lib/path-utils.js');
const { Database } = require('lib/database.js');
const Folder = require('lib/models/Folder');
const Note = require('lib/models/Note');
const Tag = require('lib/models/Tag');
const BaseItem = require('lib/models/BaseItem');
const Resource = require('lib/models/Resource');
const BaseModel = require('lib/BaseModel');
const Setting = require('lib/models/Setting');
const htmlUtils = require('lib/htmlUtils');
const markupLanguageUtils = require('lib/markupLanguageUtils');
const mimeUtils = require('lib/mime-utils.js').mime;
const { Logger } = require('lib/logger.js');
const md5 = require('md5');
const { shim } = require('lib/shim');
const HtmlToMd = require('lib/HtmlToMd');
const urlUtils = require('lib/urlUtils.js');
const ArrayUtils = require('lib/ArrayUtils.js');
const { netUtils } = require('lib/net-utils');
const { fileExtension, safeFileExtension, safeFilename, filename } = require('lib/path-utils');
const ApiResponse = require('lib/services/rest/ApiResponse');
const SearchEngineUtils = require('lib/services/SearchEngineUtils');
const { FoldersScreenUtils } = require('lib/folders-screen-utils.js');
const uri2path = require('file-uri-to-path');

class ApiError extends Error {
	constructor(message, httpCode = 400) {
		super(message);
		this.httpCode_ = httpCode;
	}

	get httpCode() {
		return this.httpCode_;
	}
}

class ErrorMethodNotAllowed extends ApiError {
	constructor(message = 'Method Not Allowed') {
		super(message, 405);
	}
}
class ErrorNotFound extends ApiError {
	constructor(message = 'Not Found') {
		super(message, 404);
	}
}
class ErrorForbidden extends ApiError {
	constructor(message = 'Forbidden') {
		super(message, 403);
	}
}
class ErrorBadRequest extends ApiError {
	constructor(message = 'Bad Request') {
		super(message, 400);
	}
}

class Api {
	constructor(token = null) {
		this.token_ = token;
		this.knownNounces_ = {};
		this.logger_ = new Logger();
	}

	get token() {
		return typeof this.token_ === 'function' ? this.token_() : this.token_;
	}

	parsePath(path) {
		path = ltrimSlashes(path);
		if (!path) return { callName: '', params: [] };

		const pathParts = path.split('/');
		const callSuffix = pathParts.splice(0, 1)[0];
		let callName = `action_${callSuffix}`;
		return {
			callName: callName,
			params: pathParts,
		};
	}

	async route(method, path, query = null, body = null, files = null) {
		if (!files) files = [];
		if (!query) query = {};

		const parsedPath = this.parsePath(path);
		if (!parsedPath.callName) throw new ErrorNotFound(); // Nothing at the root yet

		if (query && query.nounce) {
			const requestMd5 = md5(JSON.stringify([method, path, body, query, files.length]));
			if (this.knownNounces_[query.nounce] === requestMd5) {
				throw new ErrorBadRequest('Duplicate Nounce');
			}
			this.knownNounces_[query.nounce] = requestMd5;
		}

		const request = {
			method: method,
			path: ltrimSlashes(path),
			query: query ? query : {},
			body: body,
			bodyJson_: null,
			bodyJson: function(disallowedProperties = null) {
				if (!this.bodyJson_) this.bodyJson_ = JSON.parse(this.body);

				if (disallowedProperties) {
					const filteredBody = Object.assign({}, this.bodyJson_);
					for (let i = 0; i < disallowedProperties.length; i++) {
						const n = disallowedProperties[i];
						delete filteredBody[n];
					}
					return filteredBody;
				}

				return this.bodyJson_;
			},
			files: files,
		};

		let id = null;
		let link = null;
		let params = parsedPath.params;

		if (params.length >= 1) {
			id = params[0];
			params.splice(0, 1);
			if (params.length >= 1) {
				link = params[0];
				params.splice(0, 1);
			}
		}

		request.params = params;

		if (!this[parsedPath.callName]) throw new ErrorNotFound();

		try {
			return await this[parsedPath.callName](request, id, link);
		} catch (error) {
			if (!error.httpCode) error.httpCode = 500;
			throw error;
		}
	}

	setLogger(l) {
		this.logger_ = l;
	}

	logger() {
		return this.logger_;
	}

	readonlyProperties(requestMethod) {
		const output = ['created_time', 'updated_time', 'encryption_blob_encrypted', 'encryption_applied', 'encryption_cipher_text'];
		if (requestMethod !== 'POST') output.splice(0, 0, 'id');
		return output;
	}

	fields_(request, defaultFields) {
		const query = request.query;
		if (!query || !query.fields) return defaultFields;
		const fields = query.fields
			.split(',')
			.map(f => f.trim())
			.filter(f => !!f);
		return fields.length ? fields : defaultFields;
	}

	checkToken_(request) {
		// For now, whitelist some calls to allow the web clipper to work
		// without an extra auth step
		const whiteList = [['GET', 'ping'], ['GET', 'tags'], ['GET', 'folders'], ['POST', 'notes']];

		for (let i = 0; i < whiteList.length; i++) {
			if (whiteList[i][0] === request.method && whiteList[i][1] === request.path) return;
		}

		if (!this.token) return;
		if (!request.query || !request.query.token) throw new ErrorForbidden('Missing "token" parameter');
		if (request.query.token !== this.token) throw new ErrorForbidden('Invalid "token" parameter');
	}

	async defaultAction_(modelType, request, id = null, link = null) {
		this.checkToken_(request);

		if (link) throw new ErrorNotFound(); // Default action doesn't support links at all for now

		const ModelClass = BaseItem.getClassByItemType(modelType);

		const getOneModel = async () => {
			const model = await ModelClass.load(id);
			if (!model) throw new ErrorNotFound();
			return model;
		};

		if (request.method === 'GET') {
			if (id) {
				return getOneModel();
			} else {
				const options = {};
				const fields = this.fields_(request, []);
				if (fields.length) options.fields = fields;
				return await ModelClass.all(options);
			}
		}

		if (request.method === 'PUT' && id) {
			const model = await getOneModel();
			let newModel = Object.assign({}, model, request.bodyJson(this.readonlyProperties('PUT')));
			newModel = await ModelClass.save(newModel, { userSideValidation: true });
			return newModel;
		}

		if (request.method === 'DELETE' && id) {
			const model = await getOneModel();
			await ModelClass.delete(model.id);
			return;
		}

		if (request.method === 'POST') {
			const props = this.readonlyProperties('POST');
			const idIdx = props.indexOf('id');
			if (idIdx >= 0) props.splice(idIdx, 1);
			const model = request.bodyJson(props);
			const result = await ModelClass.save(model, this.defaultSaveOptions_(model, 'POST'));
			return result;
		}

		throw new ErrorMethodNotAllowed();
	}

	async action_ping(request) {
		if (request.method === 'GET') {
			return 'JoplinClipperServer';
		}

		throw new ErrorMethodNotAllowed();
	}

	async action_search(request) {
		this.checkToken_(request);

		if (request.method !== 'GET') throw new ErrorMethodNotAllowed();

		const query = request.query.query;
		if (!query) throw new ErrorBadRequest('Missing "query" parameter');

		return await SearchEngineUtils.notesForQuery(query, this.notePreviewsOptions_(request));
	}

	async action_folders(request, id = null, link = null) {
		if (request.method === 'GET' && !id) {
			const folders = await FoldersScreenUtils.allForDisplay({ fields: this.fields_(request, ['id', 'parent_id', 'title']) });
			const output = await Folder.allAsTree(folders);
			return output;
		}

		if (request.method === 'GET' && id) {
			if (link && link === 'notes') {
				const options = this.notePreviewsOptions_(request);
				return Note.previews(id, options);
			} else if (link) {
				throw new ErrorNotFound();
			}
		}

		return this.defaultAction_(BaseModel.TYPE_FOLDER, request, id, link);
	}

	async action_tags(request, id = null, link = null) {
		if (link === 'notes') {
			const tag = await Tag.load(id);
			if (!tag) throw new ErrorNotFound();

			if (request.method === 'POST') {
				const note = request.bodyJson();
				if (!note || !note.id) throw new ErrorBadRequest('Missing note ID');
				return await Tag.addNote(tag.id, note.id);
			}

			if (request.method === 'DELETE') {
				const noteId = request.params.length ? request.params[0] : null;
				if (!noteId) throw new ErrorBadRequest('Missing note ID');
				await Tag.removeNote(tag.id, noteId);
				return;
			}

			if (request.method === 'GET') {
				// Ideally we should get all this in one SQL query but for now that will do
				const noteIds = await Tag.noteIds(tag.id);
				const output = [];
				for (let i = 0; i < noteIds.length; i++) {
					const n = await Note.preview(noteIds[i], this.notePreviewsOptions_(request));
					if (!n) continue;
					output.push(n);
				}
				return output;
			}
		}

		return this.defaultAction_(BaseModel.TYPE_TAG, request, id, link);
	}

	async action_master_keys(request, id = null, link = null) {
		return this.defaultAction_(BaseModel.TYPE_MASTER_KEY, request, id, link);
	}

	async action_resources(request, id = null, link = null) {
		// fieldName: "data"
		// headers: Object
		// originalFilename: "test.jpg"
		// path: "C:\Users\Laurent\AppData\Local\Temp\BW77wkpP23iIGUstd0kDuXXC.jpg"
		// size: 164394

		if (request.method === 'GET') {
			if (link === 'file') {
				const resource = await Resource.load(id);
				if (!resource) throw new ErrorNotFound();

				const filePath = Resource.fullPath(resource);
				const buffer = await shim.fsDriver().readFile(filePath, 'Buffer');

				const response = new ApiResponse();
				response.type = 'attachment';
				response.body = buffer;
				response.contentType = resource.mime;
				response.attachmentFilename = Resource.friendlyFilename(resource);
				return response;
			}

			if (link) throw new ErrorNotFound();
		}

		if (request.method === 'POST') {
			if (!request.files.length) throw new ErrorBadRequest('Resource cannot be created without a file');
			const filePath = request.files[0].path;
			const defaultProps = request.bodyJson(this.readonlyProperties('POST'));
			return shim.createResourceFromPath(filePath, defaultProps);
		}

		return this.defaultAction_(BaseModel.TYPE_RESOURCE, request, id, link);
	}

	notePreviewsOptions_(request) {
		const fields = this.fields_(request, []); // previews() already returns default fields
		const options = {};
		if (fields.length) options.fields = fields;
		return options;
	}

	defaultSaveOptions_(model, requestMethod) {
		const options = { userSideValidation: true };
		if (requestMethod === 'POST' && model.id) options.isNew = true;
		return options;
	}

	defaultLoadOptions_(request) {
		const options = {};
		const fields = this.fields_(request, []);
		if (fields.length) options.fields = fields;
		return options;
	}

	async action_notes(request, id = null, link = null) {
		this.checkToken_(request);

		if (request.method === 'GET') {
			if (link && link === 'tags') {
				return Tag.tagsByNoteId(id);
			} else if (link && link === 'resources') {
				const note = await Note.load(id);
				const resourceIds = await Note.linkedResourceIds(note.body);
				const output = [];
				const loadOptions = this.defaultLoadOptions_(request);
				for (let resourceId of resourceIds) {
					output.push(await Resource.load(resourceId, loadOptions));
				}
				return output;
			} else if (link) {
				throw new ErrorNotFound();
			}

			const options = this.notePreviewsOptions_(request);
			if (id) {
				return await Note.preview(id, options);
			} else {
				return await Note.previews(null, options);
			}
		}

		if (request.method === 'POST') {
			const requestId = Date.now();
			const requestNote = JSON.parse(request.body);

			const allowFileProtocolImages = urlUtils.urlProtocol(requestNote.base_url).toLowerCase() === 'file:';

			const imageSizes = requestNote.image_sizes ? requestNote.image_sizes : {};

			let note = await this.requestNoteToNote_(requestNote);

			const imageUrls = ArrayUtils.unique(markupLanguageUtils.extractImageUrls(note.markup_language, note.body));

			this.logger().info(`Request (${requestId}): Downloading images: ${imageUrls.length}`);

			let result = await this.downloadImages_(imageUrls, allowFileProtocolImages);

			this.logger().info(`Request (${requestId}): Creating resources from paths: ${Object.getOwnPropertyNames(result).length}`);

			result = await this.createResourcesFromPaths_(result);
			await this.removeTempFiles_(result);
			note.body = this.replaceImageUrlsByResources_(note.markup_language, note.body, result, imageSizes);

			this.logger().info(`Request (${requestId}): Saving note...`);

			const saveOptions = this.defaultSaveOptions_(note, 'POST');
			saveOptions.autoTimestamp = false; // No auto-timestamp because user may have provided them
			const timestamp = Date.now();
			note.updated_time = timestamp;
			note.created_time = timestamp;

			note = await Note.save(note, saveOptions);

			if (requestNote.tags) {
				const tagTitles = requestNote.tags.split(',');
				await Tag.setNoteTagsByTitles(note.id, tagTitles);
			}

			if (requestNote.image_data_url) {
				note = await this.attachImageFromDataUrl_(note, requestNote.image_data_url, requestNote.crop_rect);
			}

			this.logger().info(`Request (${requestId}): Created note ${note.id}`);

			return note;
		}

		return this.defaultAction_(BaseModel.TYPE_NOTE, request, id, link);
	}

	// ========================================================================================================================
	// UTILIY FUNCTIONS
	// ========================================================================================================================

	htmlToMdParser() {
		if (this.htmlToMdParser_) return this.htmlToMdParser_;
		this.htmlToMdParser_ = new HtmlToMd();
		return this.htmlToMdParser_;
	}

	async requestNoteToNote_(requestNote) {
		const output = {
			title: requestNote.title ? requestNote.title : '',
			body: requestNote.body ? requestNote.body : '',
		};

		if (requestNote.id) output.id = requestNote.id;

		const baseUrl = requestNote.base_url ? requestNote.base_url : '';

		if (requestNote.body_html) {
			if (requestNote.convert_to === 'html') {
				const style = await this.buildNoteStyleSheet_(requestNote.stylesheets);
				const minify = require('html-minifier').minify;

				const minifyOptions = {
					// Remove all spaces and, especially, newlines from tag attributes, as that would
					// break the rendering.
					customAttrCollapse: /.*/,
					// Need to remove all whitespaces because whitespace at a beginning of a line
					// means a code block in Markdown.
					collapseWhitespace: true,
					minifyCSS: true,
					maxLineLength: 300,
				};

				const uglifycss = require('uglifycss');
				const styleString = uglifycss.processString(style.join('\n'), {
					// Need to set a max length because Ace Editor takes forever
					// to display notes with long lines.
					maxLineLen: 200,
				});

				const styleTag = style.length ? `<style>${styleString}</style>` + '\n' : '';
				output.body = styleTag + minify(requestNote.body_html, minifyOptions);
				output.body = htmlUtils.prependBaseUrl(output.body, baseUrl);
				output.markup_language = Note.MARKUP_LANGUAGE_HTML;
			} else {
				// Convert to Markdown
				// Parsing will not work if the HTML is not wrapped in a top level tag, which is not guaranteed
				// when getting the content from elsewhere. So here wrap it - it won't change anything to the final
				// rendering but it makes sure everything will be parsed.
				output.body = await this.htmlToMdParser().parse(`<div>${requestNote.body_html}</div>`, {
					baseUrl: baseUrl,
					anchorNames: requestNote.anchor_names ? requestNote.anchor_names : [],
				});
				output.markup_language = Note.MARKUP_LANGUAGE_MARKDOWN;
			}
		}

		if (requestNote.parent_id) {
			output.parent_id = requestNote.parent_id;
		} else {
			const folder = await Folder.defaultFolder();
			if (!folder) throw new Error('Cannot find folder for note');
			output.parent_id = folder.id;
		}

		if ('source_url' in requestNote) output.source_url = requestNote.source_url;
		if ('author' in requestNote) output.author = requestNote.author;
		if ('user_updated_time' in requestNote) output.user_updated_time = Database.formatValue(Database.TYPE_INT, requestNote.user_updated_time);
		if ('user_created_time' in requestNote) output.user_created_time = Database.formatValue(Database.TYPE_INT, requestNote.user_created_time);
		if ('is_todo' in requestNote) output.is_todo = Database.formatValue(Database.TYPE_INT, requestNote.is_todo);
		if ('markup_language' in requestNote) output.markup_language = Database.formatValue(Database.TYPE_INT, requestNote.markup_language);

		if (!output.markup_language) output.markup_language = Note.MARKUP_LANGUAGE_MARKDOWN;

		return output;
	}

	// Note must have been saved first
	async attachImageFromDataUrl_(note, imageDataUrl, cropRect) {
		const tempDir = Setting.value('tempDir');
		const mime = mimeUtils.fromDataUrl(imageDataUrl);
		let ext = mimeUtils.toFileExtension(mime) || '';
		if (ext) ext = `.${ext}`;
		const tempFilePath = `${tempDir}/${md5(`${Math.random()}_${Date.now()}`)}${ext}`;
		const imageConvOptions = {};
		if (cropRect) imageConvOptions.cropRect = cropRect;
		await shim.imageFromDataUrl(imageDataUrl, tempFilePath, imageConvOptions);
		return await shim.attachFileToNote(note, tempFilePath);
	}

	async tryToGuessImageExtFromMimeType_(response, imagePath) {
		const mimeType = netUtils.mimeTypeFromHeaders(response.headers);
		if (!mimeType) return imagePath;

		const newExt = mimeUtils.toFileExtension(mimeType);
		if (!newExt) return imagePath;

		const newImagePath = `${imagePath}.${newExt}`;
		await shim.fsDriver().move(imagePath, newImagePath);
		return newImagePath;
	}

	async buildNoteStyleSheet_(stylesheets) {
		if (!stylesheets) return [];

		const output = [];

		for (const stylesheet of stylesheets) {
			if (stylesheet.type === 'text') {
				output.push(stylesheet.value);
			} else if (stylesheet.type === 'url') {
				try {
					const tempPath = `${Setting.value('tempDir')}/${md5(`${Math.random()}_${Date.now()}`)}.css`;
					await shim.fetchBlob(stylesheet.value, { path: tempPath, maxRetry: 1 });
					const text = await shim.fsDriver().readFile(tempPath);
					output.push(text);
					await shim.fsDriver().remove(tempPath);
				} catch (error) {
					this.logger().warn(`Cannot download stylesheet at ${stylesheet.value}`, error);
				}
			} else {
				throw new Error(`Invalid stylesheet type: ${stylesheet.type}`);
			}
		}

		return output;
	}

	async downloadImage_(url /*, allowFileProtocolImages */) {
		const tempDir = Setting.value('tempDir');

		const isDataUrl = url && url.toLowerCase().indexOf('data:') === 0;

		const name = isDataUrl ? md5(`${Math.random()}_${Date.now()}`) : filename(url);
		let fileExt = isDataUrl ? mimeUtils.toFileExtension(mimeUtils.fromDataUrl(url)) : safeFileExtension(fileExtension(url).toLowerCase());
		if (!mimeUtils.fromFileExtension(fileExt)) fileExt = ''; // If the file extension is unknown - clear it.
		if (fileExt) fileExt = `.${fileExt}`;
		let imagePath = `${tempDir}/${safeFilename(name)}${fileExt}`;
		if (await shim.fsDriver().exists(imagePath)) imagePath = `${tempDir}/${safeFilename(name)}_${md5(`${Math.random()}_${Date.now()}`).substr(0, 10)}${fileExt}`;

		try {
			if (isDataUrl) {
				await shim.imageFromDataUrl(url, imagePath);
			} else if (urlUtils.urlProtocol(url).toLowerCase() === 'file:') {
				// Can't think of any reason to disallow this at this point
				// if (!allowFileProtocolImages) throw new Error('For security reasons, this URL with file:// protocol cannot be downloaded');
				const localPath = uri2path(url);
				await shim.fsDriver().copy(localPath, imagePath);
			} else {
				const response = await shim.fetchBlob(url, { path: imagePath, maxRetry: 1 });

				// If we could not find the file extension from the URL, try to get it
				// now based on the Content-Type header.
				if (!fileExt) imagePath = await this.tryToGuessImageExtFromMimeType_(response, imagePath);
			}
			return imagePath;
		} catch (error) {
			this.logger().warn(`Cannot download image at ${url}`, error);
			return '';
		}
	}

	async downloadImages_(urls, allowFileProtocolImages) {
		const PromisePool = require('es6-promise-pool');

		const output = {};

		const downloadOne = async url => {
			const imagePath = await this.downloadImage_(url, allowFileProtocolImages);
			if (imagePath) output[url] = { path: imagePath, originalUrl: url };
		};

		let urlIndex = 0;
		const promiseProducer = () => {
			if (urlIndex >= urls.length) return null;

			const url = urls[urlIndex++];
			return downloadOne(url);
		};

		const concurrency = 10;
		const pool = new PromisePool(promiseProducer, concurrency);
		await pool.start();

		return output;
	}

	async createResourcesFromPaths_(urls) {
		for (let url in urls) {
			if (!urls.hasOwnProperty(url)) continue;
			const urlInfo = urls[url];
			try {
				const resource = await shim.createResourceFromPath(urlInfo.path);
				urlInfo.resource = resource;
			} catch (error) {
				this.logger().warn(`Cannot create resource for ${url}`, error);
			}
		}
		return urls;
	}

	async removeTempFiles_(urls) {
		for (let url in urls) {
			if (!urls.hasOwnProperty(url)) continue;
			const urlInfo = urls[url];
			try {
				await shim.fsDriver().remove(urlInfo.path);
			} catch (error) {
				this.logger().warn(`Cannot remove ${urlInfo.path}`, error);
			}
		}
	}

	replaceImageUrlsByResources_(markupLanguage, md, urls, imageSizes) {
		const imageSizesIndexes = {};

		if (markupLanguage === Note.MARKUP_LANGUAGE_HTML) {
			return htmlUtils.replaceImageUrls(md, imageUrl => {
				const urlInfo = urls[imageUrl];
				if (!urlInfo || !urlInfo.resource) return imageUrl;
				return Resource.internalUrl(urlInfo.resource);
			});
		} else {
			// eslint-disable-next-line no-useless-escape
			return md.replace(/(!\[.*?\]\()([^\s\)]+)(.*?\))/g, (match, before, imageUrl, after) => {
				const urlInfo = urls[imageUrl];
				if (!urlInfo || !urlInfo.resource) return before + imageUrl + after;
				if (!(urlInfo.originalUrl in imageSizesIndexes)) imageSizesIndexes[urlInfo.originalUrl] = 0;

				const resourceUrl = Resource.internalUrl(urlInfo.resource);
				const imageSizesCollection = imageSizes[urlInfo.originalUrl];

				if (!imageSizesCollection) {
					// In some cases, we won't find the image size information for that particular URL. Normally
					// it will only happen when using the "Clip simplified page" feature, which can modify the
					// image URLs (for example it will select a smaller size resolution). In that case, it's
					// fine to return the image as-is because it has already good dimensions.
					return before + resourceUrl + after;
				}

				const imageSize = imageSizesCollection[imageSizesIndexes[urlInfo.originalUrl]];
				imageSizesIndexes[urlInfo.originalUrl]++;

				if (imageSize && (imageSize.naturalWidth !== imageSize.width || imageSize.naturalHeight !== imageSize.height)) {
					return `<img width="${imageSize.width}" height="${imageSize.height}" src="${resourceUrl}"/>`;
				} else {
					return before + resourceUrl + after;
				}
			});
		}
	}
}

module.exports = Api;