transmission/qt/FaviconCache.cc

169 lines
3.6 KiB
C++

/*
* This file Copyright (C) 2012-2015 Mnemosyne LLC
*
* It may be used under the GNU GPL versions 2 or 3
* or any future license endorsed by Mnemosyne LLC.
*
*/
#include <QDir>
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QStandardPaths>
#include "FaviconCache.h"
/***
****
***/
FaviconCache::FaviconCache() :
nam_(new QNetworkAccessManager(this))
{
connect(nam_, SIGNAL(finished(QNetworkReply*)), this, SLOT(onRequestFinished(QNetworkReply*)));
}
/***
****
***/
QString FaviconCache::getCacheDir()
{
QString const base = QStandardPaths::writableLocation(QStandardPaths::CacheLocation);
return QDir(base).absoluteFilePath(QStringLiteral("favicons"));
}
namespace
{
QPixmap scale(QPixmap pixmap)
{
return pixmap.scaled(FaviconCache::getIconSize(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
}
}
void FaviconCache::ensureCacheDirHasBeenScanned()
{
static bool has_been_scanned = false;
if (!has_been_scanned)
{
has_been_scanned = true;
QDir cache_dir(getCacheDir());
cache_dir.mkpath(cache_dir.absolutePath());
QStringList files = cache_dir.entryList(QDir::Files | QDir::Readable);
for (QString const& file : files)
{
QPixmap pixmap;
pixmap.load(cache_dir.absoluteFilePath(file));
if (!pixmap.isNull())
{
pixmaps_[file] = scale(pixmap);
}
}
}
}
/***
****
***/
QString FaviconCache::getDisplayName(QString const& key)
{
auto name = key;
name[0] = name.at(0).toTitleCase();
return name;
}
QString FaviconCache::getKey(QUrl const& url)
{
auto host = url.host();
// remove tld
auto const suffix = url.topLevelDomain();
host.truncate(host.size() - suffix.size());
// remove subdomain
auto const pos = host.indexOf(QLatin1Char('.'));
return pos < 0 ? host : host.remove(0, pos + 1);
}
QString FaviconCache::getKey(QString const& displayName)
{
return displayName.toLower();
}
QSize FaviconCache::getIconSize()
{
return QSize(16, 16);
}
QPixmap FaviconCache::find(QString const& key)
{
ensureCacheDirHasBeenScanned();
return pixmaps_[key];
}
QString FaviconCache::add(QUrl const& url)
{
ensureCacheDirHasBeenScanned();
QString const key = getKey(url);
if (pixmaps_.count(key) == 0)
{
// add a placholder s.t. we only ping the server once per session
pixmaps_[key] = QPixmap();
// try to download the favicon
QString const path = QStringLiteral("http://") + url.host() + QStringLiteral("/favicon.");
QStringList suffixes;
suffixes << QStringLiteral("ico") << QStringLiteral("png") << QStringLiteral("gif") << QStringLiteral("jpg");
for (QString const& suffix : suffixes)
{
nam_->get(QNetworkRequest(path + suffix));
}
}
return key;
}
void FaviconCache::onRequestFinished(QNetworkReply* reply)
{
auto const key = getKey(reply->url());
QPixmap pixmap;
QByteArray const content = reply->readAll();
if (reply->error() == QNetworkReply::NoError)
{
pixmap.loadFromData(content);
}
if (!pixmap.isNull())
{
// save it in memory...
pixmaps_[key] = scale(pixmap);
// save it on disk...
QDir cache_dir(getCacheDir());
cache_dir.mkpath(cache_dir.absolutePath());
QFile file(cache_dir.absoluteFilePath(key));
file.open(QIODevice::WriteOnly);
file.write(content);
file.close();
// notify listeners
emit pixmapReady(key);
}
}