chrome/browser/thumbnails/thumbnail_list_source.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/thumbnails/thumbnail_list_source.h"
   6
   7 #include <string>
   8
   9 #include "base/base64.h"
  10 #include "base/bind.h"
  11 #include "base/logging.h"
  12 #include "base/memory/ref_counted_memory.h"
  13 #include "base/strings/string_util.h"
  14 #include "chrome/browser/history/top_sites_factory.h"
  15 #include "chrome/browser/profiles/profile.h"
  16 #include "chrome/browser/search/instant_io_context.h"
  17 #include "chrome/browser/thumbnails/thumbnail_service.h"
  18 #include "chrome/browser/thumbnails/thumbnail_service_factory.h"
  19 #include "chrome/common/url_constants.h"
  20 #include "components/history/core/browser/top_sites.h"
  21 #include "net/base/escape.h"
  22 #include "net/url_request/url_request.h"
  23
  24 namespace {
  25
  26 const char kHtmlHeader[] =
  27     "<!DOCTYPE html>\n<html>\n<head>\n<title>TopSites Thumbnails</title>\n"
  28     "<meta charset=\"utf-8\">\n"
  29     "<style type=\"text/css\">\nimg.thumb {border: 1px solid black;}\n"
  30     "li {white-space: nowrap;}\n</style>\n";
  31 const char kHtmlBody[] = "</head>\n<body>\n";
  32 const char kHtmlFooter[] = "</body>\n</html>\n";
  33
  34 // If |want_thumbnails| == true, then renders elements in |mvurl_list| that have
  35 // thumbnails, with their thumbnails. Otherwise renders elements in |mvurl_list|
  36 // that have no thumbnails.
  37 void RenderMostVisitedURLList(
  38     const history::MostVisitedURLList& mvurl_list,
  39     const std::vector<std::string>& base64_encoded_pngs,
  40     bool want_thumbnails,
  41     std::vector<std::string>* out) {
  42   DCHECK_EQ(mvurl_list.size(), base64_encoded_pngs.size());
  43   bool doing_forced_urls = true;
  44   out->push_back("<div><b>Forced URLs:</b></div>\n"
  45                  "<div><ul>\n");
  46   for (size_t i = 0; i < mvurl_list.size(); ++i) {
  47     const history::MostVisitedURL& mvurl = mvurl_list[i];
  48     if (doing_forced_urls && mvurl.last_forced_time.is_null()) {
  49       out->push_back("</ul></div>\n"
  50                      "<div><b>Non-forced URLs:</b></div>\n"
  51                      "<div><ul>\n");
  52       doing_forced_urls = false;
  53     }
  54     bool has_thumbnail = !base64_encoded_pngs[i].empty();
  55     if (has_thumbnail == want_thumbnails) {
  56       out->push_back("<li>\n");
  57       out->push_back(net::EscapeForHTML(mvurl.url.spec()) + "\n");
  58       if (want_thumbnails) {
  59         out->push_back("<div><img class=\"thumb\" "
  60                        "src=\"data:image/png;base64," +
  61                        base64_encoded_pngs[i] + "\"/></div>\n");
  62       }
  63       if (!mvurl.redirects.empty()) {
  64         out->push_back("<ul>\n");
  65         history::RedirectList::const_iterator jt;
  66         for (jt = mvurl.redirects.begin();
  67              jt != mvurl.redirects.end(); ++jt) {
  68           out->push_back("<li>" + net::EscapeForHTML(jt->spec()) + "</li>\n");
  69         }
  70         out->push_back("</ul>\n");
  71       }
  72       out->push_back("</li>\n");
  73     }
  74   }
  75   out->push_back("</ul></div>\n");
  76 }
  77
  78 }  // namespace
  79
  80 ThumbnailListSource::ThumbnailListSource(Profile* profile)
  81     : thumbnail_service_(ThumbnailServiceFactory::GetForProfile(profile)),
  82       profile_(profile),
  83       weak_ptr_factory_(this) {
  84 }
  85
  86 ThumbnailListSource::~ThumbnailListSource() {
  87 }
  88
  89 std::string ThumbnailListSource::GetSource() const {
  90   return chrome::kChromeUIThumbnailListHost;
  91 }
  92
  93 void ThumbnailListSource::StartDataRequest(
  94     const std::string& path,
  95     int render_process_id,
  96     int render_frame_id,
  97     const content::URLDataSource::GotDataCallback& callback) {
  98   scoped_refptr<history::TopSites> top_sites =
  99       TopSitesFactory::GetForProfile(profile_);
 100   if (!top_sites) {
 101     callback.Run(NULL);
 102     return;
 103   }
 104
 105   top_sites->GetMostVisitedURLs(
 106       base::Bind(&ThumbnailListSource::OnMostVisitedURLsAvailable,
 107                  weak_ptr_factory_.GetWeakPtr(), callback),
 108       true);
 109 }
 110
 111 std::string ThumbnailListSource::GetMimeType(const std::string& path) const {
 112   return "text/html";
 113 }
 114
 115 base::MessageLoop* ThumbnailListSource::MessageLoopForRequestPath(
 116     const std::string& path) const {
 117   // TopSites can be accessed from the IO thread.
 118   return thumbnail_service_.get() ?
 119       NULL : content::URLDataSource::MessageLoopForRequestPath(path);
 120 }
 121
 122 bool ThumbnailListSource::ShouldServiceRequest(
 123     const net::URLRequest* request) const {
 124   if (request->url().SchemeIs(chrome::kChromeSearchScheme))
 125     return InstantIOContext::ShouldServiceRequest(request);
 126   return URLDataSource::ShouldServiceRequest(request);
 127 }
 128
 129 bool ThumbnailListSource::ShouldReplaceExistingSource() const {
 130   return false;
 131 }
 132
 133 void ThumbnailListSource::OnMostVisitedURLsAvailable(
 134     const content::URLDataSource::GotDataCallback& callback,
 135     const history::MostVisitedURLList& mvurl_list) {
 136   const size_t num_mv = mvurl_list.size();
 137   size_t num_mv_with_thumb = 0;
 138
 139   // Encode all available thumbnails and store into |base64_encoded_pngs|.
 140   std::vector<std::string> base64_encoded_pngs(num_mv);
 141   for (size_t i = 0; i < num_mv; ++i) {
 142     scoped_refptr<base::RefCountedMemory> data;
 143     if (thumbnail_service_->GetPageThumbnail(mvurl_list[i].url, false, &data)) {
 144       base::Base64Encode(std::string(data->front_as<char>(), data->size()),
 145                          &base64_encoded_pngs[i]);
 146       ++num_mv_with_thumb;
 147     }
 148   }
 149
 150   // Render HTML to embed URLs and thumbnails.
 151   std::vector<std::string> out;
 152   out.push_back(kHtmlHeader);
 153   out.push_back(kHtmlBody);
 154   if (num_mv_with_thumb > 0) {
 155     out.push_back("<h2>TopSites URLs with Thumbnails</h2>\n");
 156     RenderMostVisitedURLList(mvurl_list, base64_encoded_pngs, true, &out);
 157   }
 158   if (num_mv_with_thumb < num_mv) {
 159     out.push_back("<h2>TopSites URLs without Thumbnails</h2>\n");
 160     RenderMostVisitedURLList(mvurl_list, base64_encoded_pngs, false, &out);
 161   }
 162   out.push_back(kHtmlFooter);
 163
 164   std::string out_html = JoinString(out, "");
 165   callback.Run(base::RefCountedString::TakeString(&out_html));
 166 }