From de3a68ed69a3c31bb13bfaf62d1b7cca7a1a8134 Mon Sep 17 00:00:00 2001
From: Sam Foster <sfoster@mozilla.com>
Date: Fri, 15 May 2020 20:43:46 +0000
Subject: [PATCH] Bug 1191591 - Open downloaded PDFs in pdf.js viewer. r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D73400
---
 .../downloads/test/browser/browser.ini        |   1 +
 .../test/browser/browser_pdfjs_preview.js     | 345 ++++++++++++++++++
 .../components/downloads/test/browser/head.js |   1 +
 .../downloads/DownloadIntegration.jsm         |  15 +-
 .../components/downloads/DownloadUIHelper.jsm |  60 +++
 5 files changed, 421 insertions(+), 1 deletion(-)
 create mode 100644 browser/components/downloads/test/browser/browser_pdfjs_preview.js

diff --git a/browser/components/downloads/test/browser/browser.ini b/browser/components/downloads/test/browser/browser.ini
index 6fdaaf67ba56..222bce3b25e1 100644
--- a/browser/components/downloads/test/browser/browser.ini
+++ b/browser/components/downloads/test/browser/browser.ini
@@ -19,3 +19,4 @@ skip-if = true # Bug 1352792
 [browser_downloads_panel_height.js]
 [browser_downloads_autohide.js]
 [browser_go_to_download_page.js]
+[browser_pdfjs_preview.js]
\ No newline at end of file
diff --git a/browser/components/downloads/test/browser/browser_pdfjs_preview.js b/browser/components/downloads/test/browser/browser_pdfjs_preview.js
new file mode 100644
index 000000000000..e490523a6675
--- /dev/null
+++ b/browser/components/downloads/test/browser/browser_pdfjs_preview.js
@@ -0,0 +1,345 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const DATA_PDF = atob(
+  "JVBERi0xLjANCjEgMCBvYmo8PC9UeXBlL0NhdGFsb2cvUGFnZXMgMiAwIFI+PmVuZG9iaiAyIDAgb2JqPDwvVHlwZS9QYWdlcy9LaWRzWzMgMCBSXS9Db3VudCAxPj5lbmRvYmogMyAwIG9iajw8L1R5cGUvUGFnZS9NZWRpYUJveFswIDAgMyAzXT4+ZW5kb2JqDQp4cmVmDQowIDQNCjAwMDAwMDAwMDAgNjU1MzUgZg0KMDAwMDAwMDAxMCAwMDAwMCBuDQowMDAwMDAwMDUzIDAwMDAwIG4NCjAwMDAwMDAxMDIgMDAwMDAgbg0KdHJhaWxlcjw8L1NpemUgNC9Sb290IDEgMCBSPj4NCnN0YXJ0eHJlZg0KMTQ5DQolRU9G"
+);
+let gDownloadDir;
+
+/*
+  Coverage for opening downloaded PDFs from download views
+*/
+
+const TestCases = [
+  {
+    name: "Download panel, default click behavior",
+    whichUI: "downloadPanel",
+    itemSelector: "#downloadsListBox richlistitem .downloadMainArea",
+    async userEvents(itemTarget, win) {
+      EventUtils.synthesizeMouseAtCenter(itemTarget, {}, win);
+    },
+    expected: {
+      downloadCount: 1,
+      newWindow: false,
+      opensTab: true,
+      tabSelected: true,
+    },
+  },
+  {
+    name: "Download panel, open from keyboard",
+    whichUI: "downloadPanel",
+    itemSelector: "#downloadsListBox richlistitem .downloadMainArea",
+    async userEvents(itemTarget, win) {
+      itemTarget.focus();
+      EventUtils.synthesizeKey("VK_RETURN", {}, win);
+    },
+    expected: {
+      downloadCount: 1,
+      newWindow: false,
+      opensTab: true,
+      tabSelected: true,
+    },
+  },
+  {
+    name: "Library all downloads dialog, default click behavior",
+    whichUI: "allDownloads",
+    async userEvents(itemTarget, win) {
+      // double click
+      await triggerDblclickOn(itemTarget, {}, win);
+    },
+    expected: {
+      downloadCount: 1,
+      newWindow: false,
+      opensTab: true,
+      tabSelected: true,
+    },
+  },
+  {
+    name: "Library all downloads dialog, open tab from keyboard",
+    whichUI: "allDownloads",
+    async userEvents(itemTarget, win) {
+      itemTarget.focus();
+      EventUtils.synthesizeKey("VK_RETURN", {}, win);
+    },
+    expected: {
+      downloadCount: 1,
+      newWindow: false,
+      opensTab: true,
+      tabSelected: true,
+    },
+  },
+  {
+    name: "about:downloads, default click behavior",
+    whichUI: "aboutDownloads",
+    itemSelector: "#downloadsRichListBox richlistitem .downloadContainer",
+    async userEvents(itemSelector, win) {
+      let browser = win.gBrowser.selectedBrowser;
+      is(browser.currentURI.spec, "about:downloads");
+      await contentTriggerDblclickOn(itemSelector, {}, browser);
+    },
+    expected: {
+      downloadCount: 1,
+      newWindow: false,
+      opensTab: true,
+      tabSelected: true,
+    },
+  },
+];
+
+function triggerDblclickOn(target, modifiers = {}, win) {
+  let promise = BrowserTestUtils.waitForEvent(target, "dblclick");
+  EventUtils.synthesizeMouseAtCenter(
+    target,
+    Object.assign({ clickCount: 1 }, modifiers),
+    win
+  );
+  EventUtils.synthesizeMouseAtCenter(
+    target,
+    Object.assign({ clickCount: 2 }, modifiers),
+    win
+  );
+  return promise;
+}
+
+function contentTriggerDblclickOn(selector, eventModifiers = {}, browser) {
+  return SpecialPowers.spawn(
+    browser,
+    [selector, eventModifiers],
+    async function(itemSelector, modifiers) {
+      const EventUtils = ContentTaskUtils.getEventUtils(content);
+      let itemTarget = content.document.querySelector(itemSelector);
+      ok(itemTarget, "Download item target exists");
+
+      let doubleClicked = ContentTaskUtils.waitForEvent(itemTarget, "dblclick");
+      EventUtils.synthesizeMouseAtCenter(
+        itemTarget,
+        Object.assign({ clickCount: 1 }, modifiers),
+        content
+      );
+      EventUtils.synthesizeMouseAtCenter(
+        itemTarget,
+        Object.assign({ clickCount: 2 }, modifiers),
+        content
+      );
+      info("Waiting for double-click content task");
+      await doubleClicked;
+    }
+  );
+}
+
+async function createDownloadedFile(pathname, contents) {
+  let encoder = new TextEncoder();
+  let file = new FileUtils.File(pathname);
+  if (file.exists()) {
+    info(`File at ${pathname} already exists`);
+  }
+  // No post-test cleanup necessary; tmp downloads directory is already removed after each test
+  await OS.File.writeAtomic(pathname, encoder.encode(contents));
+  ok(file.exists(), `Created ${pathname}`);
+  return file;
+}
+
+async function addPDFDownload(itemData) {
+  let startTimeMs = Date.now();
+
+  let downloadPathname = OS.Path.join(gDownloadDir, itemData.targetFilename);
+  info("Creating saved download file at:" + downloadPathname);
+  let pdfFile = await createDownloadedFile(downloadPathname, DATA_PDF);
+  info("Created file at:" + pdfFile.path);
+
+  let downloadList = await Downloads.getList(Downloads.ALL);
+  let download = {
+    source: {
+      url: "https://example.com/some.pdf",
+    },
+    target: {
+      path: pdfFile.path,
+    },
+    succeeded: DownloadsCommon.DOWNLOAD_FINISHED,
+    canceled: false,
+    error: null,
+    hasPartialData: false,
+    hasBlockedData: itemData.hasBlockedData || false,
+    startTime: new Date(startTimeMs++),
+  };
+  if (itemData.errorObj) {
+    download.errorObj = itemData.errorObj;
+  }
+
+  await downloadList.add(await Downloads.createDownload(download));
+  return download;
+}
+
+async function testSetup(testData = {}) {
+  // Ensure that state is reset in case previous tests didn't finish.
+  // remove download files, empty out collections
+  info("Reset state");
+  await task_resetState();
+  if (gDownloadDir) {
+    info("Removing existing download directory: " + gDownloadDir);
+    await OS.File.removeDir(gDownloadDir, { ignoreAbsent: true });
+  }
+  gDownloadDir = await setDownloadDir();
+  info("Created download directory: " + gDownloadDir);
+}
+
+async function openDownloadPanel(expectedItemCount) {
+  // Open the user interface and wait for data to be fully loaded.
+  let richlistbox = document.getElementById("downloadsListBox");
+  await task_openPanel();
+  await TestUtils.waitForCondition(
+    () => richlistbox.childElementCount == expectedItemCount
+  );
+}
+
+async function testOpenPDFPreview({
+  name,
+  whichUI,
+  itemSelector,
+  expected,
+  userEvents,
+}) {
+  info("Test case: " + name);
+  // Wait for focus first
+  await promiseFocus();
+  await testSetup();
+
+  // Populate downloads database with the data required by this test.
+  info("Adding download objects");
+  let download = await addPDFDownload({
+    targetFilename: "downloaded.pdf",
+  });
+  info("Got download pathname:" + download.target.path);
+
+  let pdfFileURI = NetUtil.newURI(new FileUtils.File(download.target.path));
+  info("pdfFileURI:" + pdfFileURI);
+
+  let uiWindow = window;
+  let initialTab = gBrowser.selectedTab;
+  let previewWindow = window;
+  let previewTab;
+  let previewHappened;
+
+  if (expected.newWindow) {
+    info(
+      "previewHappened will wait for new browser window with url: " +
+        pdfFileURI.spec
+    );
+    // wait for a new browser window
+    previewHappened = BrowserTestUtils.waitForNewWindow({
+      anyWindow: true,
+      url: pdfFileURI.spec,
+    });
+  } else {
+    // wait for a tab to be opened
+    info("previewHappened will wait for tab with URI:" + pdfFileURI.spec);
+    previewHappened = BrowserTestUtils.waitForNewTab(
+      gBrowser,
+      pdfFileURI.spec,
+      false, // dont wait for load
+      true // any tab, not just the next one
+    );
+  }
+
+  let itemTarget;
+  switch (whichUI) {
+    case "downloadPanel":
+      info("Opening download panel");
+      await openDownloadPanel(expected.downloadCount);
+      info("/Opening download panel");
+      itemTarget = document.querySelector(itemSelector);
+      break;
+    case "allDownloads":
+      // we'll be interacting with the library dialog
+      uiWindow = await openLibrary("Downloads");
+
+      let listbox = uiWindow.document.getElementById("downloadsRichListBox");
+      ok(listbox, "download list box present");
+      // wait for the expected number of items in the view
+      await TestUtils.waitForCondition(
+        () => listbox.itemChildren.length == expected.downloadCount
+      );
+      itemTarget = listbox.itemChildren[0];
+      break;
+    case "aboutDownloads":
+      info(
+        "in aboutDownloads, initially there are tabs: " + gBrowser.tabs.length
+      );
+      await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:blank");
+      let browser = gBrowser.selectedBrowser;
+      let downloadsLoaded = BrowserTestUtils.waitForEvent(
+        browser,
+        "InitialDownloadsLoaded",
+        true
+      );
+      BrowserTestUtils.loadURI(browser, "about:downloads");
+      info("waiting for downloadsLoaded");
+      await downloadsLoaded;
+      break;
+  }
+
+  info("Executing user events");
+  info(
+    "selectedBrowser has currentURI: " +
+      gBrowser.selectedBrowser.currentURI.spec
+  );
+  await userEvents(itemTarget || itemSelector, uiWindow);
+  info("/Executing user events");
+  info("Waiting for previewHappened");
+  let results = await previewHappened;
+  if (expected.newWindow) {
+    previewWindow = results;
+    info("New window expected, got previewWindow? " + previewWindow);
+  }
+  previewTab =
+    previewWindow.gBrowser.tabs[previewWindow.gBrowser.tabs.length - 1];
+  ok(previewTab, "Got preview tab");
+
+  let isSelected = previewWindow.gBrowser.selectedTab == previewTab;
+  if (expected.tabSelected) {
+    ok(isSelected, "The preview tab was selected");
+  } else {
+    ok(!isSelected, "The preview tab was opened in the background");
+  }
+
+  is(
+    previewTab.linkedBrowser.currentURI.spec,
+    pdfFileURI.spec,
+    "previewTab has the expected currentURI"
+  );
+
+  info("cleaning up");
+  if (whichUI == "downloadPanel") {
+    DownloadsPanel.hidePanel();
+  }
+
+  info("Test opened a new UI window? " + (uiWindow !== window));
+  if (uiWindow !== window) {
+    await BrowserTestUtils.closeWindow(uiWindow);
+  }
+  if (expected.newWindow) {
+    // will also close the previewTab
+    await BrowserTestUtils.closeWindow(previewWindow);
+  } else {
+    await BrowserTestUtils.removeTab(previewTab);
+  }
+  if (gBrowser.selectedTab !== initialTab) {
+    await BrowserTestUtils.removeTab(gBrowser.selectedTab);
+  }
+}
+
+// register the tests
+for (let testData of TestCases) {
+  if (testData.skip) {
+    info("Skipping test:" + testData.name);
+    continue;
+  }
+  // use the 'name' property of each test case as the test function name
+  // so we get useful logs
+  let tmp = {
+    async [testData.name]() {
+      await testOpenPDFPreview(testData);
+    },
+  };
+  add_task(tmp[testData.name]);
+}
diff --git a/browser/components/downloads/test/browser/head.js b/browser/components/downloads/test/browser/head.js
index f5c95289f25b..a4ab848ef8ac 100644
--- a/browser/components/downloads/test/browser/head.js
+++ b/browser/components/downloads/test/browser/head.js
@@ -144,6 +144,7 @@ async function setDownloadDir() {
       ["browser.download.dir", tmpDir.path],
     ],
   });
+  return tmpDir.path;
 }
 
 let gHttpServer = null;
diff --git a/toolkit/components/downloads/DownloadIntegration.jsm b/toolkit/components/downloads/DownloadIntegration.jsm
index 02aaecaf66f7..6dbb205fcd99 100644
--- a/toolkit/components/downloads/DownloadIntegration.jsm
+++ b/toolkit/components/downloads/DownloadIntegration.jsm
@@ -787,8 +787,21 @@ var DownloadIntegration = {
     // No custom application chosen, let's launch the file with the default
     // handler. First, let's try to launch it through the MIME service.
     if (mimeInfo) {
-      mimeInfo.preferredAction = Ci.nsIMIMEInfo.useSystemDefault;
+      const PDF_CONTENT_TYPE = "application/pdf";
+      // Open PDFs internally unless explicitly configured to do otherwise
+      if (
+        mimeInfo.type == PDF_CONTENT_TYPE &&
+        !mimeInfo.alwaysAskBeforeHandling &&
+        mimeInfo.preferredAction === Ci.nsIHandlerInfo.handleInternally
+        // TODO: also preview for save to disk and always ask file actions?
+      ) {
+        DownloadUIHelper.loadFileIn(file, {
+          isPrivate: aDownload.source.isPrivate,
+        });
+        return;
+      }
 
+      mimeInfo.preferredAction = Ci.nsIMIMEInfo.useSystemDefault;
       try {
         this.launchFile(file, mimeInfo);
         return;
diff --git a/toolkit/components/downloads/DownloadUIHelper.jsm b/toolkit/components/downloads/DownloadUIHelper.jsm
index 92c44d26616a..72424f7613e3 100644
--- a/toolkit/components/downloads/DownloadUIHelper.jsm
+++ b/toolkit/components/downloads/DownloadUIHelper.jsm
@@ -24,6 +24,12 @@ ChromeUtils.defineModuleGetter(
   "resource://gre/modules/Services.jsm"
 );
 
+// BrowserWindowTracker and PrivateBrowsingUtils are only used when opening downloaded files into a browser window
+XPCOMUtils.defineLazyModuleGetters(this, {
+  BrowserWindowTracker: "resource:///modules/BrowserWindowTracker.jsm",
+  PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.jsm",
+});
+
 const kStringBundleUrl =
   "chrome://mozapps/locale/downloads/downloads.properties";
 
@@ -57,6 +63,60 @@ var DownloadUIHelper = {
   getPrompter(aParent) {
     return new DownloadPrompter(aParent || null);
   },
+
+  /**
+   * Open the given file as a file: URI in the active window
+   *
+   * @param nsIFile file       The downloaded file
+   * @param options.browserWin Optional chrome window where we could open the file URI
+   * @param options.where      String indicating how to open the URI.
+   *                           One of "window", "tab", "tabshifted"
+   * @param options.isPrivate  Open in private window or not
+   */
+  loadFileIn(file, { browserWin, where = "tab", isPrivate } = {}) {
+    let fileURI = Services.io.newFileURI(file);
+    let allowPrivate =
+      isPrivate || PrivateBrowsingUtils.permanentPrivateBrowsing;
+
+    // we'll need a private window for a private download, or if we're in private-only mode
+    // but otherwise we want to open files in a non-private window
+    if (
+      !browserWin ||
+      browserWin.document.documentElement.getAttribute("windowtype") !==
+        "navigator:browser"
+    ) {
+      browserWin = BrowserWindowTracker.getTopWindow({ private: allowPrivate });
+    }
+    // if there is no suitable browser window, we'll need to open one and ignore any other `where` value
+    // this can happen if the library dialog is the only open window
+    if (!browserWin) {
+      // There is no browser window open, so open a new one.
+      let args = Cc["@mozilla.org/array;1"].createInstance(Ci.nsIMutableArray);
+      let strURI = Cc["@mozilla.org/supports-string;1"].createInstance(
+        Ci.nsISupportsString
+      );
+      strURI.data = fileURI.spec;
+      args.appendElement(strURI);
+      let features = "chrome,dialog=no,all";
+      if (isPrivate) {
+        features += ",private";
+      }
+      browserWin = Services.ww.openWindow(
+        null,
+        AppConstants.BROWSER_CHROME_URL,
+        null,
+        features,
+        args
+      );
+      return;
+    }
+
+    // a browser window will have the helpers from utilityOverlay.js
+    browserWin.openTrustedLinkIn(fileURI.spec, where, {
+      triggeringPrincipal: Services.scriptSecurityManager.getSystemPrincipal(),
+      private: isPrivate,
+    });
+  },
 };
 
 /**