Thread for generating thumbnail images;

Used for card list;
Implemented reordering from card list

git-svn-id: svn://svn.code.sf.net/p/magicseteditor/code/trunk@115 0fc631ac-6414-0410-93d0-97cfa31319b6

src/gui/thumbnail_thread.cpp

@@ -0,0 +1,212 @@
+//+----------------------------------------------------------------------------+
+//| Description:  Magic Set Editor - Program to make Magic (tm) cards          |
+//| Copyright:    (C) 2001 - 2006 Twan van Laarhoven                           |
+//| License:      GNU General Public License 2 or later (see file COPYING)     |
+//+----------------------------------------------------------------------------+
+
+// ----------------------------------------------------------------------------- : Includes
+
+#include <gui/thumbnail_thread.hpp>
+#include <wx/thread.h>
+
+typedef pair<ThumbnailRequestP,Image> pair_ThumbnailRequestP_Image;
+DECLARE_TYPEOF_COLLECTION(pair_ThumbnailRequestP_Image);
+
+// ----------------------------------------------------------------------------- : ThumbnailThreadWorker
+
+class ThumbnailThreadWorker : public wxThread {
+  public:
+	ThumbnailThreadWorker(ThumbnailThread* parent);
+	
+	virtual ExitCode Entry();
+	
+	ThumbnailRequestP current; ///< Request we are working on
+	ThumbnailThread*  parent;
+	bool              stop; ///< Suspend computation
+};
+
+ThumbnailThreadWorker::ThumbnailThreadWorker(ThumbnailThread* parent)
+	: parent(parent)
+	, stop(false)
+{}
+
+wxThread::ExitCode ThumbnailThreadWorker::Entry() {
+	while (true) {
+		do {
+			Sleep(1);
+			if (TestDestroy()) return 0;
+		} while (stop);
+		// get a request
+		{
+			wxMutexLocker lock(parent->mutex);
+			if (parent->open_requests.empty()) {
+				parent->worker = nullptr;
+				return 0; // No more requests
+			}
+			current = parent->open_requests.front();
+			parent->open_requests.pop_front();
+		}
+		// perform request
+		if (TestDestroy()) return 0;
+		Image img = current->generate();
+		if (TestDestroy()) return 0;
+		// store result
+		{
+			wxMutexLocker lock(parent->mutex);
+			parent->closed_requests.push_back(make_pair(current,img));
+			current.reset();
+			parent->completed.Signal();
+		}
+	}
+}
+
+bool operator < (const ThumbnailRequestP& a, const ThumbnailRequestP& b) {
+	if (a->owner < b->owner) return true;
+	if (a->owner > b->owner) return false;
+	return a->cache_name < b->cache_name;
+}
+
+// ----------------------------------------------------------------------------- : ThumbnailThread
+
+ThumbnailThread thumbnail_thread;
+
+ThumbnailThread::ThumbnailThread()
+	: completed(mutex)
+	, worker(nullptr)
+{}
+
+ThumbnailThread::~ThumbnailThread() {
+	abortAll();
+}
+
+String user_settings_dir();
+String image_cache_dir() {
+	String dir = user_settings_dir() + _("/cache");
+	if (!wxDirExists(dir)) wxMkDir(dir);
+	return dir + _("/");
+}
+
+String ThumbnailThread::safeFilename(const String& str) {
+	String ret; ret.reserve(str.size());
+	FOR_EACH_CONST(c, str) {
+		if (isAlnum(c)) {
+			ret += c;
+		} else if (c==_(' ') || c==_('-')) {
+			ret += _('-');
+		} else {
+			ret += _('_');
+		}
+	}
+	return ret;
+}
+
+void ThumbnailThread::request(const ThumbnailRequestP& request) {
+	assert(wxThread::IsMain());
+	// Is the request in progress?
+	if (request_names.find(request) != request_names.end()) {
+		return;
+	}
+	request_names.insert(request);
+	// Is the image in the cache?
+	String filename = image_cache_dir() + safeFilename(request->cache_name) + _(".png");
+	wxFileName fn(filename);
+	if (fn.FileExists()) {
+		wxDateTime modified;
+		if (fn.GetTimes(0, &modified, 0) && modified >= request->modified) {
+			// yes it is
+			Image img(filename);
+			request->store(img);
+			return;
+		}
+	}
+	// request generation
+	{
+		wxMutexLocker lock(mutex);
+		open_requests.push_back(request);
+	}
+	// is there a worker?
+	if (!worker) {
+		worker = new ThumbnailThreadWorker(this);
+		worker->Create();
+		worker->Run();
+	}
+}
+
+bool ThumbnailThread::done(void* owner) {
+	assert(wxThread::IsMain());
+	// find finished requests
+	vector<pair<ThumbnailRequestP,Image> > finished;
+	{
+		wxMutexLocker lock(mutex);
+		for (size_t i = 0 ; i < closed_requests.size() ; ) {
+			if (closed_requests[i].first->owner == owner) {
+				// move to finished list
+				finished.push_back(closed_requests[i]);
+				closed_requests.erase(closed_requests.begin() + i, closed_requests.begin() + i + 1);
+			} else {
+				++i;
+			}
+		}
+	}
+	// store them
+	FOR_EACH(r, finished) {
+		// store image
+		r.first->store(r.second);
+		// store in cache
+		String filename = image_cache_dir() + safeFilename(r.first->cache_name) + _(".png");
+		r.second.SaveFile(filename, wxBITMAP_TYPE_PNG);
+		// set modification time
+		wxFileName fn(filename);
+		fn.SetTimes(0, &r.first->modified, 0);
+		// remove from name list
+		request_names.erase(r.first);
+	}
+	return !finished.empty();
+}
+
+void ThumbnailThread::abort(void* owner) {
+	assert(wxThread::IsMain());
+	mutex.Lock();
+	if (worker && worker->current->owner == owner) {
+		// a request for this owner is in progress, wait until it is done
+		worker->stop = true;
+		completed.Wait();
+		mutex.Lock();
+		worker->stop = false;
+	}
+	// remove open requests for this owner
+	for (size_t i = 0 ; i < open_requests.size() ; ) {
+		if (open_requests[i]->owner == owner) {
+			// remove
+			open_requests.erase(open_requests.begin() + i, open_requests.begin() + i + 1);
+			request_names.erase(open_requests[i]);
+		} else {
+			++i;
+		}
+	}
+	// remove closed requests for this owner
+	for (size_t i = 0 ; i < closed_requests.size() ; ) {
+		if (closed_requests[i].first->owner == owner) {
+			// remove
+			closed_requests.erase(closed_requests.begin() + i, closed_requests.begin() + i + 1);
+			request_names.erase(closed_requests[i].first);
+		} else {
+			++i;
+		}
+	}
+	mutex.Unlock();
+}
+
+void ThumbnailThread::abortAll() {
+	assert(wxThread::IsMain());
+	mutex.Lock();
+	open_requests.clear();
+	closed_requests.clear();
+	request_names.clear();
+	if (worker) {
+		// a request is in progress, wait until it is done, killing the worker
+		completed.Wait();
+	} else {
+		mutex.Unlock();
+	}
+}