From 13dc800e964567dbe87501574a2cb61c4db0f15c Mon Sep 17 00:00:00 2001
From: Ankush Dutt <ankushd100@gmail.com>
Date: Wed, 2 Aug 2023 15:15:46 +0530
Subject: [PATCH] BACKENDS: Implement interrupt/cancel pending DLC downloads

---
 backends/dlc/dlcmanager.cpp   |  5 ++++-
 backends/dlc/dlcmanager.h     |  2 ++
 backends/dlc/scummvmcloud.cpp | 14 ++++++++++++++
 gui/downloaddlcsdialog.cpp    |  7 +++++--
 4 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/backends/dlc/dlcmanager.cpp b/backends/dlc/dlcmanager.cpp
index 8f09298cf8a..a331a5dc891 100644
--- a/backends/dlc/dlcmanager.cpp
+++ b/backends/dlc/dlcmanager.cpp
@@ -58,6 +58,7 @@ void DLCManager::refreshLauncherGameList() {
 void DLCManager::addDownload(uint32 idx) {
 	_dlcs[idx]->state = DLCDesc::kInProgress;
 	_queuedDownloadTasks.push(_dlcs[idx]);
+	_dlcsInProgress.push_back(_dlcs[idx]);
 	if (!_isDLCDownloading) {
 		// if queue is not already processing
 		DLCManager::processDownloadQueue();
@@ -74,6 +75,7 @@ void DLCManager::processDownloadQueue() {
 		} else {
 			// state is already cancelled/downloaded -> skip download
 			_queuedDownloadTasks.pop();
+			_dlcsInProgress.remove_at(0);
 			// process next download in the queue
 			processDownloadQueue();
 		}
@@ -89,8 +91,9 @@ void DLCManager::startDownloadAsync(const Common::String &id, const Common::Stri
 }
 
 bool DLCManager::cancelDownload(uint32 idx) {
-	if (_currentDownloadingDLC == _dlcs[idx]->id) {
+	if (_queuedDownloadTasks.front()->idx == idx) {
 		// if already downloading, interrupt startDownloadAsync
+		_interruptCurrentDownload = true;
 	} else {
 		// if not started, skip it in processDownload()
 		_dlcs[idx]->state = DLCDesc::kCancelled;
diff --git a/backends/dlc/dlcmanager.h b/backends/dlc/dlcmanager.h
index b5448b49214..20493cfc590 100644
--- a/backends/dlc/dlcmanager.h
+++ b/backends/dlc/dlcmanager.h
@@ -42,8 +42,10 @@ class DLCManager : public Common::Singleton<DLCManager>, public GUI::CommandSend
 
 public:
 	bool _fetchDLCs = false;
+	bool _interruptCurrentDownload = false;
 	uint32 _currentDownloadedSize;
 	Common::Array<DLCDesc*> _dlcs;
+	Common::Array<DLCDesc*> _dlcsInProgress;
 	Common::Queue<DLCDesc*> _queuedDownloadTasks;
 	
 	DLCManager();
diff --git a/backends/dlc/scummvmcloud.cpp b/backends/dlc/scummvmcloud.cpp
index 1df9d3ad204..77da3d71347 100644
--- a/backends/dlc/scummvmcloud.cpp
+++ b/backends/dlc/scummvmcloud.cpp
@@ -91,6 +91,18 @@ void ScummVMCloud::getAllDLCs() {
 void ScummVMCloud::downloadFileCallback(Networking::DataResponse r) {
 	Networking::SessionFileResponse *response = static_cast<Networking::SessionFileResponse *>(r.value);
 	DLCMan._currentDownloadedSize += response->len;
+	if (DLCMan._interruptCurrentDownload) {
+		_rq->close();
+		DLCMan._interruptCurrentDownload = false;
+		// delete the download cache (the incomplete .zip)
+		Common::Path relativeFilePath = Common::Path(DLCMan._queuedDownloadTasks.front()->id);
+		removeCacheFile(relativeFilePath);
+		// handle next download
+		DLCMan._queuedDownloadTasks.front()->state = DLCDesc::kDownloaded;
+		DLCMan._queuedDownloadTasks.pop();
+		DLCMan._dlcsInProgress.remove_at(0);
+		DLCMan.processDownloadQueue();
+	}
 	if (response->eos) {
 		warning("downloaded");
 		_rq->close(); // delete request
@@ -106,6 +118,7 @@ void ScummVMCloud::downloadFileCallback(Networking::DataResponse r) {
 		// handle next download
 		DLCMan._queuedDownloadTasks.front()->state = DLCDesc::kDownloaded;
 		DLCMan._queuedDownloadTasks.pop();
+		DLCMan._dlcsInProgress.remove_at(0);
 		DLCMan.processDownloadQueue();
 	}
 }
@@ -114,6 +127,7 @@ void ScummVMCloud::errorCallback(Networking::ErrorResponse error) {
 	// error downloading - start next download in queue
 	DLCMan._queuedDownloadTasks.front()->state = DLCDesc::kErrorDownloading;
 	DLCMan._queuedDownloadTasks.pop();
+	DLCMan._dlcsInProgress.remove_at(0);
 	DLCMan.processDownloadQueue();
 }
 
diff --git a/gui/downloaddlcsdialog.cpp b/gui/downloaddlcsdialog.cpp
index 0c980980f4b..51f34e8d0b2 100644
--- a/gui/downloaddlcsdialog.cpp
+++ b/gui/downloaddlcsdialog.cpp
@@ -84,9 +84,11 @@ void DownloadDLCsDialog::refreshWidgets() {
 		_currentDownloadLabel->setLabel(DLCMan._queuedDownloadTasks.front()->name);
 		_downloadedSizeLabel->setLabel(getSizeLabelText());
 
-		for (auto it : DLCMan._dlcs) {
+		for (auto it : DLCMan._dlcsInProgress) {
 			if (it->state == DLC::DLCDesc::kInProgress) {
 				pendingList.push_back(it->name);
+			} else {
+				pendingList.push_back("[Cancelled] " + it->name);
 			}
 		}
 		_pendingDownloadsList->setList(pendingList);
@@ -127,7 +129,8 @@ void DownloadDLCsDialog::handleTickle() {
 void DownloadDLCsDialog::handleCommand(CommandSender *sender, uint32 cmd, uint32 data) {
 	switch (cmd) {
 	case kCancelSelectedCmd: {
-		// set state of selected DLC to kCancelled
+		uint32 idx = DLCMan._dlcsInProgress[_pendingDownloadsList->getSelected()]->idx;
+		DLCMan.cancelDownload(idx);
 		}
 		break;
 	default: