/* -*- Mode: indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* vim: set sts=2 sw=2 et tw=80: */
"use strict";

const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;

Cu.import("resource://gre/modules/Task.jsm");

XPCOMUtils.defineLazyModuleGetter(this, "PlacesUtils",
                                  "resource://gre/modules/PlacesUtils.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Preferences",
                                  "resource://gre/modules/Preferences.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Sanitizer",
                                  "resource:///modules/Sanitizer.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Services",
                                  "resource://gre/modules/Services.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "setTimeout",
                                  "resource://gre/modules/Timer.jsm");

XPCOMUtils.defineLazyServiceGetter(this, "serviceWorkerManager",
                                   "@mozilla.org/serviceworkers/manager;1",
                                   "nsIServiceWorkerManager");

/**
* A number of iterations after which to yield time back
* to the system.
*/
const YIELD_PERIOD = 10;

const PREF_DOMAIN = "privacy.cpd.";

XPCOMUtils.defineLazyGetter(this, "sanitizer", () => {
  let sanitizer = new Sanitizer();
  sanitizer.prefDomain = PREF_DOMAIN;
  return sanitizer;
});

function makeRange(options) {
  return (options.since == null) ?
    null :
    [PlacesUtils.toPRTime(options.since), PlacesUtils.toPRTime(Date.now())];
}

function clearCache() {
  // Clearing the cache does not support timestamps.
  return sanitizer.items.cache.clear();
}

let clearCookies = Task.async(function* (options) {
  let cookieMgr = Services.cookies;
  // This code has been borrowed from sanitize.js.
  let yieldCounter = 0;

  if (options.since) {
    // Iterate through the cookies and delete any created after our cutoff.
    let cookiesEnum = cookieMgr.enumerator;
    while (cookiesEnum.hasMoreElements()) {
      let cookie = cookiesEnum.getNext().QueryInterface(Ci.nsICookie2);

      if (cookie.creationTime >= PlacesUtils.toPRTime(options.since)) {
        // This cookie was created after our cutoff, clear it.
        cookieMgr.remove(cookie.host, cookie.name, cookie.path,
                         false, cookie.originAttributes);

        if (++yieldCounter % YIELD_PERIOD == 0) {
          yield new Promise(resolve => setTimeout(resolve, 0)); // Don't block the main thread too long.
        }
      }
    }
  } else {
    // Remove everything.
    cookieMgr.removeAll();
  }
});

function clearDownloads(options) {
  return sanitizer.items.downloads.clear(makeRange(options));
}

function clearFormData(options) {
  return sanitizer.items.formdata.clear(makeRange(options));
}

function clearHistory(options) {
  return sanitizer.items.history.clear(makeRange(options));
}

let clearPasswords = Task.async(function* (options) {
  let loginManager = Services.logins;
  let yieldCounter = 0;

  if (options.since) {
    // Iterate through the logins and delete any updated after our cutoff.
    let logins = loginManager.getAllLogins();
    for (let login of logins) {
      login.QueryInterface(Ci.nsILoginMetaInfo);
      if (login.timePasswordChanged >= options.since) {
        loginManager.removeLogin(login);
        if (++yieldCounter % YIELD_PERIOD == 0) {
          yield new Promise(resolve => setTimeout(resolve, 0)); // Don't block the main thread too long.
        }
      }
    }
  } else {
    // Remove everything.
    loginManager.removeAllLogins();
  }
});

function clearPluginData(options) {
  return sanitizer.items.pluginData.clear(makeRange(options));
}

let clearServiceWorkers = Task.async(function* () {
  // Clearing service workers does not support timestamps.
  let yieldCounter = 0;

  // Iterate through the service workers and remove them.
  let serviceWorkers = serviceWorkerManager.getAllRegistrations();
  for (let i = 0; i < serviceWorkers.length; i++) {
    let sw = serviceWorkers.queryElementAt(i, Ci.nsIServiceWorkerRegistrationInfo);
    let host = sw.principal.URI.host;
    serviceWorkerManager.removeAndPropagate(host);
    if (++yieldCounter % YIELD_PERIOD == 0) {
      yield new Promise(resolve => setTimeout(resolve, 0)); // Don't block the main thread too long.
    }
  }
});

function doRemoval(options, dataToRemove, extension) {
  if (options.originTypes &&
      (options.originTypes.protectedWeb || options.originTypes.extension)) {
    return Promise.reject(
      {message: "Firefox does not support protectedWeb or extension as originTypes."});
  }

  let removalPromises = [];
  let invalidDataTypes = [];
  for (let dataType in dataToRemove) {
    if (dataToRemove[dataType]) {
      switch (dataType) {
        case "cache":
          removalPromises.push(clearCache());
          break;
        case "cookies":
          removalPromises.push(clearCookies(options));
          break;
        case "downloads":
          removalPromises.push(clearDownloads(options));
          break;
        case "formData":
          removalPromises.push(clearFormData(options));
          break;
        case "history":
          removalPromises.push(clearHistory(options));
          break;
        case "passwords":
          removalPromises.push(clearPasswords(options));
          break;
        case "pluginData":
          removalPromises.push(clearPluginData(options));
          break;
        case "serviceWorkers":
          removalPromises.push(clearServiceWorkers());
          break;
        default:
          invalidDataTypes.push(dataType);
      }
    }
  }
  if (extension && invalidDataTypes.length) {
    extension.logger.warn(
      `Firefox does not support dataTypes: ${invalidDataTypes.toString()}.`);
  }
  return Promise.all(removalPromises);
}

extensions.registerSchemaAPI("browsingData", "addon_parent", context => {
  let {extension} = context;
  return {
    browsingData: {
      settings() {
        const PREF_DOMAIN = "privacy.cpd.";
        // The following prefs are the only ones in Firefox that match corresponding
        // values used by Chrome when rerturning settings.
        const PREF_LIST = ["cache", "cookies", "history", "formdata", "downloads"];

        // since will be the start of what is returned by Sanitizer.getClearRange
        // divided by 1000 to convert to ms.
        // If Sanitizer.getClearRange returns undefined that means the range is
        // currently "Everything", so we should set since to 0.
        let clearRange = Sanitizer.getClearRange();
        let since = clearRange ? clearRange[0] / 1000 : 0;
        let options = {since};

        let dataToRemove = {};
        let dataRemovalPermitted = {};

        for (let item of PREF_LIST) {
          // The property formData needs a different case than the
          // formdata preference.
          const name = item === "formdata" ? "formData" : item;
          dataToRemove[name] = Preferences.get(`${PREF_DOMAIN}${item}`);
          // Firefox doesn't have the same concept of dataRemovalPermitted
          // as Chrome, so it will always be true.
          dataRemovalPermitted[name] = true;
        }

        return Promise.resolve({options, dataToRemove, dataRemovalPermitted});
      },
      remove(options, dataToRemove) {
        return doRemoval(options, dataToRemove, extension);
      },
      removeCache(options) {
        return doRemoval(options, {cache: true});
      },
      removeCookies(options) {
        return doRemoval(options, {cookies: true});
      },
      removeDownloads(options) {
        return doRemoval(options, {downloads: true});
      },
      removeFormData(options) {
        return doRemoval(options, {formData: true});
      },
      removeHistory(options) {
        return doRemoval(options, {history: true});
      },
      removePasswords(options) {
        return doRemoval(options, {passwords: true});
      },
      removePluginData(options) {
        return doRemoval(options, {pluginData: true});
      },
    },
  };
});