/*
 * decaffeinate suggestions:
 * DS101: Remove unnecessary use of Array.from
 * DS102: Remove unnecessary code created because of implicit returns
 * DS205: Consider reworking code to avoid use of IIFEs
 * DS207: Consider shorter variations of null checks
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
let RequestParser;
const settings = require("settings-sharelatex");

module.exports = (RequestParser = {
	VALID_COMPILERS: ["pdflatex", "latex", "xelatex", "lualatex"],
	MAX_TIMEOUT: 600,

	parse(body, callback) {
		let resource;
		if (callback == null) { callback = function(error, data) {}; }
		const response = {};

		if ((body.compile == null)) {
			return callback("top level object should have a compile attribute");
		}

		const { compile } = body;
		if (!compile.options) { compile.options = {}; }

		try {
			response.compiler = this._parseAttribute("compiler",
				compile.options.compiler, {
				validValues: this.VALID_COMPILERS,
				default: "pdflatex",
				type: "string"
			}
			);
			response.timeout = this._parseAttribute("timeout",
				compile.options.timeout, {
				default: RequestParser.MAX_TIMEOUT,
				type: "number"
			}
			);
			response.imageName = this._parseAttribute("imageName",
				compile.options.imageName,
				{type: "string"});
			response.draft = this._parseAttribute("draft",
				compile.options.draft, {
				default: false,
				type: "boolean"
			}
			);
			response.check = this._parseAttribute("check",
				compile.options.check,
				{type: "string"});
			response.flags = this._parseAttribute("flags",
				compile.options.flags, {
				default: [],
				type: "object"
			}
			);

			// The syncType specifies whether the request contains all
			// resources (full) or only those resources to be updated
			// in-place (incremental).
			response.syncType = this._parseAttribute("syncType",
				compile.options.syncType, {
				validValues: ["full", "incremental"],
				type: "string"
			}
			);

			// The syncState is an identifier passed in with the request
			// which has the property that it changes when any resource is
			// added, deleted, moved or renamed.
			//
			// on syncType full the syncState identifier is passed in and
			// stored
			//
			// on syncType incremental the syncState identifier must match
			// the stored value
			response.syncState = this._parseAttribute("syncState",
				compile.options.syncState,
				{type: "string"});

			if (response.timeout > RequestParser.MAX_TIMEOUT) {
				response.timeout = RequestParser.MAX_TIMEOUT;
			}
			response.timeout = response.timeout * 1000; // milliseconds

			response.resources = ((() => {
				const result = [];
				for (resource of Array.from((compile.resources || []))) { 					result.push(this._parseResource(resource));
				}
				return result;
			})());

			const rootResourcePath = this._parseAttribute("rootResourcePath",
				compile.rootResourcePath, {
				default: "main.tex",
				type: "string"
			}
			);
			const originalRootResourcePath = rootResourcePath;
			const sanitizedRootResourcePath = RequestParser._sanitizePath(rootResourcePath);
			response.rootResourcePath = RequestParser._checkPath(sanitizedRootResourcePath);

			for (resource of Array.from(response.resources)) {
				if (resource.path === originalRootResourcePath) {
					resource.path = sanitizedRootResourcePath;
				}
			}
		} catch (error1) {
			const error = error1;
			return callback(error);
		}

		return callback(null, response);
	},

	_parseResource(resource) {
		let modified;
		if ((resource.path == null) || (typeof resource.path !== "string")) {
			throw "all resources should have a path attribute";
		}

		if (resource.modified != null) {
			modified = new Date(resource.modified);
			if (isNaN(modified.getTime())) {
				throw `resource modified date could not be understood: ${resource.modified}`;
			}
		}

		if ((resource.url == null) && (resource.content == null)) {
			throw "all resources should have either a url or content attribute";
		}
		if ((resource.content != null) && (typeof resource.content !== "string")) {
			throw "content attribute should be a string";
		}
		if ((resource.url != null) && (typeof resource.url !== "string")) {
			throw "url attribute should be a string";
		}

		return {
			path: resource.path,
			modified,
			url: resource.url,
			content: resource.content
		};
	},

	_parseAttribute(name, attribute, options) {
		if (attribute != null) {
			if (options.validValues != null) {
				if (options.validValues.indexOf(attribute) === -1) {
					throw `${name} attribute should be one of: ${options.validValues.join(", ")}`;
				}
			}
			if (options.type != null) {
				if (typeof attribute !== options.type) {
					throw `${name} attribute should be a ${options.type}`;
				}
			}
		} else {
			if (options.default != null) { return options.default; }
		}
		return attribute;
	},

	_sanitizePath(path) {
		// See http://php.net/manual/en/function.escapeshellcmd.php
		return path.replace(/[\#\&\;\`\|\*\?\~\<\>\^\(\)\[\]\{\}\$\\\x0A\xFF\x00]/g, "");
	},

	_checkPath(path) {
		// check that the request does not use a relative path
		for (let dir of Array.from(path.split('/'))) {
			if (dir === '..') {
				throw "relative path in root resource";
			}
		}
		return path;
	}
});