PicasaAlbumTableReader for Media Galleries API

webkit/fileapi/media/picasa/pmp_albumdata_table_reader.cc

+// 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.
+
+#include "pmp_albumdata_table_reader.h"
+
+#include <vector>
+
+#include "base/utf_string_conversions.h"
+#include "webkit/fileapi/media/picasa/pmp_column_reader.h"
+#include "webkit/fileapi/media/picasa/pmp_constants.h"
+
+namespace picasaimport {
+
+namespace {
+
+const int kColCategory = 0;
+const int kColDate     = 1;
+const int kColFilename = 2;
+const int kColName     = 3;
+const int kColToken    = 4;
+const int kColUid      = 5;
+
+const uint16 albumdata_field_types[] = {
+    PMP_UINT32_TYPE,
+    PMP_DOUBLE64_TYPE,
+    PMP_STRING_TYPE,
+    PMP_STRING_TYPE,
+    PMP_STRING_TYPE,
+    PMP_STRING_TYPE
+};
+
+int albumdata_columns_len = 6;
+
+const uint16 kAlbumCategoryUserAlbum = 0;
+const uint16 kAlbumCategoryFolder    = 2;
+const uint16 kAlbumCategoryInvalid   = 0xffff;
+
+const int kPmpVariantTimeEpochYear = 1899;
+const int kPmpVariantTimeEpochMonth = 12;
+const int kPmpVariantTimeEpochDay = 30;
+
+// |variant_time| is specified as the number of days from Dec 30, 1899.
+base::Time TimeFromMicrosoftVariantTime(double variant_time) {
+  base::Time::Exploded variant_epoch;
+
+  // First set to Dec 30, 1899, (variant time epoch).
+  variant_epoch.year = kPmpVariantTimeEpochYear;
+  variant_epoch.month = kPmpVariantTimeEpochMonth;
+  variant_epoch.day_of_month = kPmpVariantTimeEpochDay;
+
+  base::TimeDelta variant_delta = base::TimeDelta::FromMicroseconds(

[vandebo (ex-Chrome), 2013/04/06 01:10:30]

why not FromDays ?

[tommycli, 2013/04/08 17:17:29]

Because the argument is an integer, and VariantTime specifies the specific time
during the day in the fractional part of the floating point.

+      static_cast<int64>(variant_time * base::Time::kMicrosecondsPerDay));
+
+  return base::Time::FromLocalExploded(variant_epoch) + variant_delta;
+}
+
+}  // namespace
+
+PmpAlbumdataTableReader::PmpAlbumdataTableReader() : PmpTableReader() { }
+
+PmpAlbumdataTableReader::~PmpAlbumdataTableReader() { }
+
+bool PmpAlbumdataTableReader::Init(const base::FilePath& directory_path) {
+  const std::string kAlbumTokenPrefix = "]album:";
+
+  std::vector<std::string> column_names;
+  column_names.push_back("category");
+  column_names.push_back("date");
+  column_names.push_back("filename");
+  column_names.push_back("name");
+  column_names.push_back("token");
+  column_names.push_back("uid");
+
+  if(!PmpTableReader::Init("albumdata", directory_path, column_names))
+    return false;
+
+  std::vector<const PmpColumnReader*> columns = GetColumns();
+
+  // Abort if column types aren't as expected.
+  for(int i = 0; i < albumdata_columns_len; i++) {
+    if(columns[i]->field_type() != albumdata_field_types[i])
+      return false;
+  }
+
+  for(uint32 i = 0; i < RowCount(); i++) {
+    uint32 category = kAlbumCategoryInvalid;
+    double date;
+    std::string name, filename, token, uid;
+
+    if(!columns[kColCategory]->ReadUInt32(i, &category) ||

[vandebo (ex-Chrome), 2013/04/06 01:10:30]

columns[constant number] suggests that maybe a better interface for the table
reader is to return a map from column name to column reader.

[tommycli, 2013/04/08 17:17:29]

Agreed. I'd like to move forward with what we have right now and circle back to
improve the interface later.

[vandebo (ex-Chrome), 2013/04/08 19:02:30]

The other CL can go in as is, but lets fix it in this CL.

[tommycli, 2013/04/09 00:45:33]

Done.

+       !columns[kColDate]->ReadDouble64(i, &date) ||
+       !columns[kColName]->ReadString(i, &name) || name.empty()) {
+      continue;
+    }
+
+    AlbumInfo album;
+    album.name = name;
+    album.timestamp = TimeFromMicrosoftVariantTime(date);
+
+    switch(category) {
+      case kAlbumCategoryUserAlbum: {
+        if(!columns[kColName]->ReadString(i, &name) || name.empty() ||
+           !columns[kColToken]->ReadString(i, &token) || token.empty() ||
+           !columns[kColUid]->ReadString(i, &uid) || uid.empty() ||
+           token.substr(0, kAlbumTokenPrefix.size()) != kAlbumTokenPrefix) {
+          continue;
+        }
+
+        album.category = PICASA_USER_ALBUM;
+        album.name = name;
+        album.uid = uid;
+
+        user_albums_.push_back(album);
+        break;
+      }
+      case kAlbumCategoryFolder: {
+        if(!columns[kColFilename]->ReadString(i, &filename) || filename.empty())
+          continue;
+
+        album.category = PICASA_FOLDER;
+#if defined(OS_WIN)

[tommycli, 2013/04/05 23:04:08]

I'm using this ugly idiom so often. file_path.h already has a
FILE_PATH_LITERAL(x) macro for string literals. Should I add a
FILE_PATH_FROM_UTF8(x) macro for std::string UTF-8s?

[vandebo (ex-Chrome), 2013/04/06 01:10:30]

The bar for adding to base is pretty high...

+        album.path = base::FilePath(UTF8ToUTF16(filename));
+#else
+        album.path = base::FilePath(filename);
+#endif
+
+        folders_.push_back(album);

[vandebo (ex-Chrome), 2013/04/06 01:10:30]

It looks like some some fields are valid only for certain types.  Maybe a per
type struct would be better.  Have a struct with fields that aren't always valid
is one of my pet peeves.

[tommycli, 2013/04/08 17:17:29]

Done.

+        break;
+      }
+      default: {
+        break;
+      }
+    }
+  }
+
+  return true;
+}
+
+}  // namespace picasaimport