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js/modules/types/message.js

@@ -47,6 +47,8 @@ const PRIVATE = 'private';
 // Version 9
 //   - Attachments: Expand the set of unicode characters we filter out of
 //     attachment filenames
+// Version 10
+//   - Preview: A new type of attachment can be included in a message.
 
 const INITIAL_SCHEMA_VERSION = 0;
 
@@ -232,6 +234,46 @@ exports._mapQuotedAttachments = upgradeAttachment => async (
   });
 };
 
+//      _mapPreviewAttachments :: (PreviewAttachment -> Promise PreviewAttachment) ->
+//                               (Message, Context) ->
+//                               Promise Message
+exports._mapPreviewAttachments = upgradeAttachment => async (
+  message,
+  context
+) => {
+  if (!message.preview) {
+    return message;
+  }
+  if (!context || !isObject(context.logger)) {
+    throw new Error('_mapPreviewAttachments: context must have logger object');
+  }
+  const { logger } = context;
+
+  const upgradeWithContext = async preview => {
+    const { image } = preview;
+    if (!image) {
+      return preview;
+    }
+
+    if (!image.data && !image.path) {
+      logger.warn('Preview did not have image data; removing it');
+      return omit(preview, ['image']);
+    }
+
+    const upgradedImage = await upgradeAttachment(image, context);
+    return Object.assign({}, preview, {
+      image: upgradedImage,
+    });
+  };
+
+  const preview = await Promise.all(
+    (message.preview || []).map(upgradeWithContext)
+  );
+  return Object.assign({}, message, {
+    preview,
+  });
+};
+
 const toVersion0 = async (message, context) =>
   exports.initializeSchemaVersion({ message, logger: context.logger });
 const toVersion1 = exports._withSchemaVersion({
@@ -277,6 +319,10 @@ const toVersion9 = exports._withSchemaVersion({
   schemaVersion: 9,
   upgrade: exports._mapAttachments(Attachment.replaceUnicodeV2),
 });
+const toVersion10 = exports._withSchemaVersion({
+  schemaVersion: 10,
+  upgrade: exports._mapPreviewAttachments(Attachment.migrateDataToFileSystem),
+});
 
 const VERSIONS = [
   toVersion0,
@@ -289,9 +335,13 @@ const VERSIONS = [
   toVersion7,
   toVersion8,
   toVersion9,
+  toVersion10,
 ];
 exports.CURRENT_SCHEMA_VERSION = VERSIONS.length - 1;
 
+// We need dimensions and screenshots for images for proper display
+exports.VERSION_NEEDED_FOR_DISPLAY = 9;
+
 // UpgradeStep
 exports.upgradeSchema = async (
   rawMessage,
@@ -408,6 +458,31 @@ exports.loadQuoteData = loadAttachmentData => {
   };
 };
 
+exports.loadPreviewData = loadAttachmentData => {
+  if (!isFunction(loadAttachmentData)) {
+    throw new TypeError('loadPreviewData: loadAttachmentData is required');
+  }
+
+  return async preview => {
+    if (!preview || !preview.length) {
+      return [];
+    }
+
+    return Promise.all(
+      preview.map(async () => {
+        if (!preview.image) {
+          return preview;
+        }
+
+        return {
+          ...preview,
+          image: await loadAttachmentData(preview.image),
+        };
+      })
+    );
+  };
+};
+
 exports.deleteAllExternalFiles = ({ deleteAttachmentData, deleteOnDisk }) => {
   if (!isFunction(deleteAttachmentData)) {
     throw new TypeError(
@@ -422,7 +497,7 @@ exports.deleteAllExternalFiles = ({ deleteAttachmentData, deleteOnDisk }) => {
   }
 
   return async message => {
-    const { attachments, quote, contact } = message;
+    const { attachments, quote, contact, preview } = message;
 
     if (attachments && attachments.length) {
       await Promise.all(attachments.map(deleteAttachmentData));
@@ -451,6 +526,18 @@ exports.deleteAllExternalFiles = ({ deleteAttachmentData, deleteOnDisk }) => {
         })
       );
     }
+
+    if (preview && preview.length) {
+      await Promise.all(
+        preview.map(async item => {
+          const { image } = item;
+
+          if (image && image.path) {
+            await deleteOnDisk(image.path);
+          }
+        })
+      );
+    }
   };
 };
 
@@ -480,11 +567,12 @@ exports.createAttachmentDataWriter = ({
       logger,
     });
 
-    const { attachments, quote, contact } = message;
+    const { attachments, quote, contact, preview } = message;
     const hasFilesToWrite =
       (quote && quote.attachments && quote.attachments.length > 0) ||
       (attachments && attachments.length > 0) ||
-      (contact && contact.length > 0);
+      (contact && contact.length > 0) ||
+      (preview && preview.length > 0);
 
     if (!hasFilesToWrite) {
       return message;
@@ -545,11 +633,25 @@ exports.createAttachmentDataWriter = ({
       });
     };
 
+    const writePreviewImage = async item => {
+      const { image } = item;
+      if (!image) {
+        return omit(item, ['image']);
+      }
+
+      await writeExistingAttachmentData(image);
+
+      return Object.assign({}, item, {
+        image: omit(image, ['data']),
+      });
+    };
+
     const messageWithoutAttachmentData = Object.assign(
       {},
       await writeThumbnails(message, { logger }),
       {
         contact: await Promise.all((contact || []).map(writeContactAvatar)),
+        preview: await Promise.all((preview || []).map(writePreviewImage)),
         attachments: await Promise.all(
           (attachments || []).map(async attachment => {
             await writeExistingAttachmentData(attachment);