"use strict";
const path = require("path");
const fs = require("pn/fs");
const vm = require("vm");
const toughCookie = require("tough-cookie");
const sniffHTMLEncoding = require("html-encoding-sniffer");
const whatwgURL = require("whatwg-url");
const whatwgEncoding = require("whatwg-encoding");
const { URL } = require("whatwg-url");
const MIMEType = require("whatwg-mimetype");
const idlUtils = require("./jsdom/living/generated/utils.js");
const VirtualConsole = require("./jsdom/virtual-console.js");
const Window = require("./jsdom/browser/Window.js");
const { parseIntoDocument } = require("./jsdom/browser/parser");
const { fragmentSerialization } = require("./jsdom/living/domparsing/serialization.js");
const ResourceLoader = require("./jsdom/browser/resources/resource-loader.js");
const NoOpResourceLoader = require("./jsdom/browser/resources/no-op-resource-loader.js");

// This symbol allows us to smuggle a non-public option through to the JSDOM constructor, for use by JSDOM.fromURL.
const transportLayerEncodingLabelHiddenOption = Symbol("transportLayerEncodingLabel");

class CookieJar extends toughCookie.CookieJar {
  constructor(store, options) {
    // jsdom cookie jars must be loose by default
    super(store, Object.assign({ looseMode: true }, options));
  }
}

const window = Symbol("window");
let sharedFragmentDocument = null;

class JSDOM {
  constructor(input, options = {}) {
    const mimeType = new MIMEType(options.contentType === undefined ? "text/html" : options.contentType);
    const { html, encoding } = normalizeHTML(input, options[transportLayerEncodingLabelHiddenOption], mimeType);

    options = transformOptions(options, encoding, mimeType);

    this[window] = new Window(options.windowOptions);

    const documentImpl = idlUtils.implForWrapper(this[window]._document);

    options.beforeParse(this[window]._globalProxy);

    parseIntoDocument(html, documentImpl);

    documentImpl.close();
  }

  get window() {
    // It's important to grab the global proxy, instead of just the result of `new Window(...)`, since otherwise things
    // like `window.eval` don't exist.
    return this[window]._globalProxy;
  }

  get virtualConsole() {
    return this[window]._virtualConsole;
  }

  get cookieJar() {
    // TODO NEWAPI move _cookieJar to window probably
    return idlUtils.implForWrapper(this[window]._document)._cookieJar;
  }

  serialize() {
    return fragmentSerialization(idlUtils.implForWrapper(this[window]._document), { requireWellFormed: false });
  }

  nodeLocation(node) {
    if (!idlUtils.implForWrapper(this[window]._document)._parseOptions.sourceCodeLocationInfo) {
      throw new Error("Location information was not saved for this jsdom. Use includeNodeLocations during creation.");
    }

    return idlUtils.implForWrapper(node).sourceCodeLocation;
  }

  runVMScript(script, options) {
    if (!vm.isContext(this[window])) {
      throw new TypeError("This jsdom was not configured to allow script running. " +
        "Use the runScripts option during creation.");
    }

    return script.runInContext(this[window], options);
  }

  reconfigure(settings) {
    if ("windowTop" in settings) {
      this[window]._top = settings.windowTop;
    }

    if ("url" in settings) {
      const document = idlUtils.implForWrapper(this[window]._document);

      const url = whatwgURL.parseURL(settings.url);
      if (url === null) {
        throw new TypeError(`Could not parse "${settings.url}" as a URL`);
      }

      document._URL = url;
      document.origin = whatwgURL.serializeURLOrigin(document._URL);
    }
  }

  static fragment(string = "") {
    if (!sharedFragmentDocument) {
      sharedFragmentDocument = (new JSDOM()).window.document;
    }

    const template = sharedFragmentDocument.createElement("template");
    template.innerHTML = string;
    return template.content;
  }

  static fromURL(url, options = {}) {
    return Promise.resolve().then(() => {
      const parsedURL = new URL(url);
      url = parsedURL.href;
      options = normalizeFromURLOptions(options);

      const resourceLoader = resourcesToResourceLoader(options.resources);
      const resourceLoaderForInitialRequest = resourceLoader.constructor === NoOpResourceLoader ?
        new ResourceLoader() :
        resourceLoader;

      const req = resourceLoaderForInitialRequest.fetch(url, {
        accept: "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
        cookieJar: options.cookieJar,
        referrer: options.referrer
      });

      return req.then(body => {
        const res = req.response;

        let transportLayerEncodingLabel;
        if ("content-type" in res.headers) {
          const mimeType = new MIMEType(res.headers["content-type"]);
          transportLayerEncodingLabel = mimeType.parameters.get("charset");
        }

        options = Object.assign(options, {
          url: req.href + parsedURL.hash,
          contentType: res.headers["content-type"],
          referrer: req.getHeader("referer"),
          [transportLayerEncodingLabelHiddenOption]: transportLayerEncodingLabel
        });

        return new JSDOM(body, options);
      });
    });
  }

  static fromFile(filename, options = {}) {
    return Promise.resolve().then(() => {
      options = normalizeFromFileOptions(filename, options);

      return fs.readFile(filename).then(buffer => {
        return new JSDOM(buffer, options);
      });
    });
  }
}

function normalizeFromURLOptions(options) {
  // Checks on options that are invalid for `fromURL`
  if (options.url !== undefined) {
    throw new TypeError("Cannot supply a url option when using fromURL");
  }
  if (options.contentType !== undefined) {
    throw new TypeError("Cannot supply a contentType option when using fromURL");
  }

  // Normalization of options which must be done before the rest of the fromURL code can use them, because they are
  // given to request()
  const normalized = Object.assign({}, options);

  if (options.referrer !== undefined) {
    normalized.referrer = (new URL(options.referrer)).href;
  }

  if (options.cookieJar === undefined) {
    normalized.cookieJar = new CookieJar();
  }

  return normalized;

  // All other options don't need to be processed yet, and can be taken care of in the normal course of things when
  // `fromURL` calls `new JSDOM(html, options)`.
}

function normalizeFromFileOptions(filename, options) {
  const normalized = Object.assign({}, options);

  if (normalized.contentType === undefined) {
    const extname = path.extname(filename);
    if (extname === ".xhtml" || extname === ".xml") {
      normalized.contentType = "application/xhtml+xml";
    }
  }

  if (normalized.url === undefined) {
    normalized.url = new URL("file:" + path.resolve(filename));
  }

  return normalized;
}

function transformOptions(options, encoding, mimeType) {
  const transformed = {
    windowOptions: {
      // Defaults
      url: "about:blank",
      referrer: "",
      contentType: "text/html",
      parsingMode: "html",
      parseOptions: { sourceCodeLocationInfo: false },
      runScripts: undefined,
      encoding,
      pretendToBeVisual: false,
      storageQuota: 5000000,

      // Defaults filled in later
      resourceLoader: undefined,
      virtualConsole: undefined,
      cookieJar: undefined
    },

    // Defaults
    beforeParse() { }
  };

  // options.contentType was parsed into mimeType by the caller.
  if (!mimeType.isHTML() && !mimeType.isXML()) {
    throw new RangeError(`The given content type of "${options.contentType}" was not a HTML or XML content type`);
  }

  transformed.windowOptions.contentType = mimeType.essence;
  transformed.windowOptions.parsingMode = mimeType.isHTML() ? "html" : "xml";

  if (options.url !== undefined) {
    transformed.windowOptions.url = (new URL(options.url)).href;
  }

  if (options.referrer !== undefined) {
    transformed.windowOptions.referrer = (new URL(options.referrer)).href;
  }

  if (options.includeNodeLocations) {
    if (transformed.windowOptions.parsingMode === "xml") {
      throw new TypeError("Cannot set includeNodeLocations to true with an XML content type");
    }

    transformed.windowOptions.parseOptions = { sourceCodeLocationInfo: true };
  }

  transformed.windowOptions.cookieJar = options.cookieJar === undefined ?
                                       new CookieJar() :
                                       options.cookieJar;

  transformed.windowOptions.virtualConsole = options.virtualConsole === undefined ?
                                            (new VirtualConsole()).sendTo(console) :
                                            options.virtualConsole;

  if (!(transformed.windowOptions.virtualConsole instanceof VirtualConsole)) {
    throw new TypeError("virtualConsole must be an instance of VirtualConsole");
  }

  transformed.windowOptions.resourceLoader = resourcesToResourceLoader(options.resources);

  if (options.runScripts !== undefined) {
    transformed.windowOptions.runScripts = String(options.runScripts);
    if (transformed.windowOptions.runScripts !== "dangerously" &&
        transformed.windowOptions.runScripts !== "outside-only") {
      throw new RangeError(`runScripts must be undefined, "dangerously", or "outside-only"`);
    }
  }

  if (options.beforeParse !== undefined) {
    transformed.beforeParse = options.beforeParse;
  }

  if (options.pretendToBeVisual !== undefined) {
    transformed.windowOptions.pretendToBeVisual = Boolean(options.pretendToBeVisual);
  }

  if (options.storageQuota !== undefined) {
    transformed.windowOptions.storageQuota = Number(options.storageQuota);
  }

  // concurrentNodeIterators??

  return transformed;
}

function normalizeHTML(html = "", transportLayerEncodingLabel, mimeType) {
  let encoding = "UTF-8";

  if (ArrayBuffer.isView(html)) {
    html = Buffer.from(html.buffer, html.byteOffset, html.byteLength);
  } else if (html instanceof ArrayBuffer) {
    html = Buffer.from(html);
  }

  if (Buffer.isBuffer(html)) {
    encoding = sniffHTMLEncoding(html, {
      defaultEncoding: mimeType.isXML() ? "UTF-8" : "windows-1252",
      transportLayerEncodingLabel
    });
    html = whatwgEncoding.decode(html, encoding);
  } else {
    html = String(html);
  }

  return { html, encoding };
}

function resourcesToResourceLoader(resources) {
  switch (resources) {
    case undefined: {
      return new NoOpResourceLoader();
    }
    case "usable": {
      return new ResourceLoader();
    }
    default: {
      if (!(resources instanceof ResourceLoader)) {
        throw new TypeError("resources must be an instance of ResourceLoader");
      }
      return resources;
    }
  }
}

exports.JSDOM = JSDOM;

exports.VirtualConsole = VirtualConsole;
exports.CookieJar = CookieJar;
exports.ResourceLoader = ResourceLoader;

exports.toughCookie = toughCookie;
