// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

/** @type {string}
 * @const
 */
var FEEDBACK_LANDING_PAGE =
    'https://support.google.com/chrome/go/feedback_confirmation';

/** @type {number}
 * @const
 */
var MAX_ATTACH_FILE_SIZE = 3 * 1024 * 1024;

/**
 * @type {number}
 * @const
 */
var FEEDBACK_MIN_WIDTH = 500;

/**
 * @type {number}
 * @const
 */
var FEEDBACK_MIN_HEIGHT = 585;

/**
 * @type {number}
 * @const
 */
var FEEDBACK_MIN_HEIGHT_LOGIN = 482;

/** @type {number}
 * @const
 */
var CONTENT_MARGIN_HEIGHT = 40;

/** @type {number}
 * @const
 */
var MAX_SCREENSHOT_WIDTH = 100;

/** @type {string}
 * @const
 */
var SYSINFO_WINDOW_ID = 'sysinfo_window';

/** @type {string}
 * @const
 */
var STATS_WINDOW_ID = 'stats_window';

/**
 * Feedback flow defined in feedback_private.idl.
 * @enum {string}
 */
var FeedbackFlow = {
  REGULAR: 'regular',  // Flow in a regular user session.
  LOGIN: 'login'       // Flow on the login screen.
};

var attachedFileBlob = null;
var lastReader = null;

/**
 * Determines whether the system information associated with this instance of
 * the feedback window has been received.
 * @type {boolean}
 */
var isSystemInfoReady = false;

/**
 * The callback used by the sys_info_page to receive the event that the system
 * information is ready.
 * @type {function(sysInfo)}
 */
var sysInfoPageOnSysInfoReadyCallback = null;

/**
 * Reads the selected file when the user selects a file.
 * @param {Event} fileSelectedEvent The onChanged event for the file input box.
 */
function onFileSelected(fileSelectedEvent) {
  $('attach-error').hidden = true;
  var file = fileSelectedEvent.target.files[0];
  if (!file) {
    // User canceled file selection.
    attachedFileBlob = null;
    return;
  }

  if (file.size > MAX_ATTACH_FILE_SIZE) {
    $('attach-error').hidden = false;

    // Clear our selected file.
    $('attach-file').value = '';
    attachedFileBlob = null;
    return;
  }

  attachedFileBlob = file.slice();
}

/**
 * Clears the file that was attached to the report with the initial request.
 * Instead we will now show the attach file button in case the user wants to
 * attach another file.
 */
function clearAttachedFile() {
  $('custom-file-container').hidden = true;
  attachedFileBlob = null;
  feedbackInfo.attachedFile = null;
  $('attach-file').hidden = false;
}

/**
 * Creates a closure that creates or shows a window with the given url.
 * @param {string} windowId A string with the ID of the window we are opening.
 * @param {string} url The destination URL of the new window.
 * @return {function()} A function to be called to open the window.
 */
function windowOpener(windowId, url) {
  return function(e) {
    e.preventDefault();
    chrome.app.window.create(url, {id: windowId});
  };
}

/**
 * Opens a new window with chrome://slow_trace, downloading performance data.
 */
function openSlowTraceWindow() {
  chrome.app.window.create(
      'chrome://slow_trace/tracing.zip#' + feedbackInfo.traceId);
}

/**
 * Sends the report; after the report is sent, we need to be redirected to
 * the landing page, but we shouldn't be able to navigate back, hence
 * we open the landing page in a new tab and sendReport closes this tab.
 * @return {boolean} True if the report was sent.
 */
function sendReport() {
  if ($('description-text').value.length == 0) {
    var description = $('description-text');
    description.placeholder = loadTimeData.getString('no-description');
    description.focus();
    return false;
  }

  // Prevent double clicking from sending additional reports.
  $('send-report-button').disabled = true;
  console.log('Feedback: Sending report');
  if (!feedbackInfo.attachedFile && attachedFileBlob) {
    feedbackInfo.attachedFile = { name: $('attach-file').value,
                                  data: attachedFileBlob };
  }

  feedbackInfo.description = $('description-text').value;
  feedbackInfo.pageUrl = $('page-url-text').value;
  feedbackInfo.email = $('user-email-text').value;

  var useSystemInfo = false;
  var useHistograms = false;
  if ($('sys-info-checkbox') != null &&
      $('sys-info-checkbox').checked) {
    // Send histograms along with system info.
    useSystemInfo = useHistograms = true;
  }
<if expr="chromeos">
  if ($('performance-info-checkbox') == null ||
      !($('performance-info-checkbox').checked)) {
    feedbackInfo.traceId = null;
  }
</if>

  feedbackInfo.sendHistograms = useHistograms;

  // If the user doesn't want to send the screenshot.
  if (!$('screenshot-checkbox').checked)
    feedbackInfo.screenshot = null;

  // Request sending the report, show the landing page (if allowed), and close
  // this window right away. The FeedbackRequest object that represents this
  // report will take care of sending the report in the background.
  sendFeedbackReport(useSystemInfo);
  if (feedbackInfo.flow != FeedbackFlow.LOGIN)
    window.open(FEEDBACK_LANDING_PAGE, '_blank');
  window.close();
  return true;
}

/**
 * Click listener for the cancel button.
 * @param {Event} e The click event being handled.
 */
function cancel(e) {
  e.preventDefault();
  window.close();
}

/**
 * Converts a blob data URL to a blob object.
 * @param {string} url The data URL to convert.
 * @return {Blob} Blob object containing the data.
 */
function dataUrlToBlob(url) {
  var mimeString = url.split(',')[0].split(':')[1].split(';')[0];
  var data = atob(url.split(',')[1]);
  var dataArray = [];
  for (var i = 0; i < data.length; ++i)
    dataArray.push(data.charCodeAt(i));

  return new Blob([new Uint8Array(dataArray)], {type: mimeString});
}

<if expr="chromeos">
/**
 * Update the page when performance feedback state is changed.
 */
function performanceFeedbackChanged() {
  if ($('performance-info-checkbox').checked) {
    $('attach-file').disabled = true;
    $('attach-file').checked = false;

    $('screenshot-checkbox').disabled = true;
    $('screenshot-checkbox').checked = false;
  } else {
    $('attach-file').disabled = false;
    $('screenshot-checkbox').disabled = false;
  }
}
</if>

function resizeAppWindow() {
  // We pick the width from the titlebar, which has no margins.
  var width = $('title-bar').scrollWidth;
  if (width < FEEDBACK_MIN_WIDTH)
    width = FEEDBACK_MIN_WIDTH;

  // We get the height by adding the titlebar height and the content height +
  // margins. We can't get the margins for the content-pane here by using
  // style.margin - the variable seems to not exist.
  var height = $('title-bar').scrollHeight +
      $('content-pane').scrollHeight + CONTENT_MARGIN_HEIGHT;

  var minHeight = FEEDBACK_MIN_HEIGHT;
  if (feedbackInfo.flow == FeedbackFlow.LOGIN)
    minHeight = FEEDBACK_MIN_HEIGHT_LOGIN;
  height = Math.max(height, minHeight);

  chrome.app.window.current().resizeTo(width, height);
}

/**
 * A callback to be invoked when the background page of this extension receives
 * the system information.
 */
function onSystemInformation() {
  isSystemInfoReady = true;
  // In case the sys_info_page needs to be notified by this event, do so.
  if (sysInfoPageOnSysInfoReadyCallback != null) {
    sysInfoPageOnSysInfoReadyCallback(feedbackInfo.systemInformation);
    sysInfoPageOnSysInfoReadyCallback = null;
  }
}

/**
 * Initializes our page.
 * Flow:
 * .) DOMContent Loaded        -> . Request feedbackInfo object
 *                                . Setup page event handlers
 * .) Feedback Object Received -> . take screenshot
 *                                . request email
 *                                . request System info
 *                                . request i18n strings
 * .) Screenshot taken         -> . Show Feedback window.
 */
function initialize() {
  // Add listener to receive the feedback info object.
  chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) {
    if (request.sentFromEventPage) {
      if (!feedbackInfo.flow)
        feedbackInfo.flow = FeedbackFlow.REGULAR;

      $('description-text').textContent = feedbackInfo.description;
      if (feedbackInfo.pageUrl)
        $('page-url-text').value = feedbackInfo.pageUrl;

      takeScreenshot(function(screenshotCanvas) {
        // We've taken our screenshot, show the feedback page without any
        // further delay.
        window.webkitRequestAnimationFrame(function() {
          resizeAppWindow();
        });
        chrome.app.window.current().show();

        var screenshotDataUrl = screenshotCanvas.toDataURL('image/png');
        $('screenshot-image').src = screenshotDataUrl;
        $('screenshot-image').classList.toggle('wide-screen',
            $('screenshot-image').width > MAX_SCREENSHOT_WIDTH);
        feedbackInfo.screenshot = dataUrlToBlob(screenshotDataUrl);
      });

      chrome.feedbackPrivate.getUserEmail(function(email) {
        $('user-email-text').value = email;
      });

      // Initiate getting the system info.
      isSystemInfoReady = false;
      getSystemInformation(onSystemInformation);

      // An extension called us with an attached file.
      if (feedbackInfo.attachedFile) {
        $('attached-filename-text').textContent =
            feedbackInfo.attachedFile.name;
        attachedFileBlob = feedbackInfo.attachedFile.data;
        $('custom-file-container').hidden = false;
        $('attach-file').hidden = true;
      }

      // No URL and file attachment for login screen feedback.
      if (feedbackInfo.flow == FeedbackFlow.LOGIN) {
        $('page-url').hidden = true;
        $('attach-file-container').hidden = true;
        $('attach-file-note').hidden = true;
      }

<if expr="chromeos">
      if (feedbackInfo.traceId && ($('performance-info-area'))) {
        $('performance-info-area').hidden = false;
        $('performance-info-checkbox').checked = true;
        performanceFeedbackChanged();
        $('performance-info-link').onclick = openSlowTraceWindow;
      }
</if>

      chrome.feedbackPrivate.getStrings(function(strings) {
        loadTimeData.data = strings;
        i18nTemplate.process(document, loadTimeData);

        if ($('sys-info-url')) {
          // Opens a new window showing the full anonymized system+app
          // information.
          $('sys-info-url').onclick = function() {
            var win = chrome.app.window.get(SYSINFO_WINDOW_ID);
            if (win) {
              win.show();
              return;
            }
            chrome.app.window.create(
              '/html/sys_info.html', {
                frame: 'chrome',
                id: SYSINFO_WINDOW_ID,
                width: 600,
                height: 400,
                hidden: false,
                resizable: true
              }, function(appWindow) {
                // Define functions for the newly created window.

                // Gets the full system information for the new window.
                appWindow.contentWindow.getFullSystemInfo =
                    function(callback) {
                      if (isSystemInfoReady) {
                        callback(feedbackInfo.systemInformation);
                        return;
                      }

                      sysInfoPageOnSysInfoReadyCallback = callback;
                    };

                // Returns the loadTimeData for the new window.
                appWindow.contentWindow.getLoadTimeData = function() {
                  return loadTimeData;
                };
            });
          };
        }
        if ($('histograms-url')) {
          // Opens a new window showing the histogram metrics.
          $('histograms-url').onclick =
              windowOpener(STATS_WINDOW_ID, 'chrome://histograms');
        }
        // Make sure our focus starts on the description field.
        $('description-text').focus();
      });
    }
  });

  window.addEventListener('DOMContentLoaded', function() {
    // Ready to receive the feedback object.
    chrome.runtime.sendMessage({ready: true});

    // Setup our event handlers.
    $('attach-file').addEventListener('change', onFileSelected);
    $('send-report-button').onclick = sendReport;
    $('cancel-button').onclick = cancel;
    $('remove-attached-file').onclick = clearAttachedFile;
<if expr="chromeos">
    $('performance-info-checkbox').addEventListener(
        'change', performanceFeedbackChanged);
</if>
  });
}

initialize();