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