From 765df313e065f8401319c68ba70cd41b0bc34c9d Mon Sep 17 00:00:00 2001
From: rtk0c <mail.tianyig@gmail.com>
Date: Wed, 12 May 2021 13:23:56 -0700
Subject: Start to work on actually rendering the node graph

---
 core/src/UI/UI_Workflows.cpp | 122 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 113 insertions(+), 9 deletions(-)

(limited to 'core/src/UI/UI_Workflows.cpp')

diff --git a/core/src/UI/UI_Workflows.cpp b/core/src/UI/UI_Workflows.cpp
index f9857a1..7aefeab 100644
--- a/core/src/UI/UI_Workflows.cpp
+++ b/core/src/UI/UI_Workflows.cpp
@@ -17,9 +17,9 @@
 namespace ImNodes = ax::NodeEditor;
 
 namespace {
-class WorkflowCreationMenu
+class WorkflowDatabase
 {
-private:
+public:
 	using WorkflowNodeConstructor = std::unique_ptr<WorkflowNode> (*)();
 
 	enum Category
@@ -39,6 +39,7 @@ private:
 		Category Category;
 	};
 
+private:
 	std::vector<Candidate> mCandidates;
 
 #define SUB_RANGE_ACCESS(Type, AccessorName, storage, begin, nextBegin) \
@@ -53,6 +54,7 @@ private:
 	int mSystemInputNodes;
 	int mOutputOffset;
 
+public:
 	SUB_RANGE_ACCESS(Candidate, GetNumericNodes, mCandidates, 0, mTextOffset);
 	SUB_RANGE_ACCESS(Candidate, GetTextNodes, mCandidates, mTextOffset, mDocumentOffset);
 	SUB_RANGE_ACCESS(Candidate, GetDocumentNodes, mCandidates, mDocumentOffset, mUserInputOffset);
@@ -63,12 +65,6 @@ private:
 #undef SUB_RANGE_ACCESS
 
 public:
-	WorkflowCreationMenu()
-	{
-		SetupCandidates();
-	}
-
-private:
 	void SetupCandidates()
 	{
 		// Numeric nodes offset start at 0
@@ -140,11 +136,13 @@ class WorkflowUI
 private:
 	Workflow* mWorkflow;
 	ImNodes::EditorContext* mContext;
+	WorkflowDatabase mWorkflowDatabase;
 
 public:
 	WorkflowUI()
 	{
 		mContext = ImNodes::CreateEditor();
+		mWorkflowDatabase.SetupCandidates();
 	}
 
 	~WorkflowUI()
@@ -157,6 +155,8 @@ public:
 		ImNodes::SetCurrentEditor(mContext);
 		ImNodes::Begin("");
 
+		const char* tooltipMessage = nullptr;
+
 		for (auto& node : mWorkflow->GetNodes()) {
 			if (!node) continue;
 
@@ -168,8 +168,112 @@ public:
 		for (auto& conn : mWorkflow->GetConnections()) {
 			if (!conn.IsValid()) continue;
 
-			// TODO create link
+			auto srcId = mWorkflow->GetNodes()[conn.SourceNode]->GetOutputPinUniqueId(conn.SourcePin);
+			auto dstId = mWorkflow->GetNodes()[conn.DestinationNode]->GetInputPinUniqueId(conn.DestinationPin);
+			ImNodes::Link(conn.GetLinkId(), srcId, dstId);
+		}
+
+		if (ImNodes::BeginCreate()) {
+			ImNodes::PinId src = 0, dst = 0;
+			if (ImNodes::QueryNewLink(&src, &dst)) {
+				if (!src || !dst) {
+					goto createError;
+				}
+
+				auto [srcNode, srcPinId, srcIsOutput] = mWorkflow->DisassembleGlobalPinId((size_t)src);
+				auto [dstNode, dstPinId, dstIsOutput] = mWorkflow->DisassembleGlobalPinId((size_t)dst);
+
+				if (srcNode == dstNode) {
+					ImNodes::RejectNewItem();
+					goto createError;
+				}
+
+				if (srcIsOutput == dstIsOutput) {
+					ImNodes::RejectNewItem();
+					goto createError;
+				}
+
+				auto srcPin = srcNode->GetOutputPin(srcPinId);
+				auto dstPin = dstNode->GetOutputPin(dstPinId);
+
+				if (srcPin.MatchingType != dstPin.MatchingType) {
+					ImNodes::RejectNewItem();
+					goto createError;
+				}
+
+				if (ImNodes::AcceptNewItem()) {
+					mWorkflow->Connect(*srcNode, srcPinId, *dstNode, dstPinId);
+				}
+			}
+
+			ImNodes::PinId newNodePin = 0;
+			if (ImNodes::QueryNewNode(&newNodePin)) {
+				auto [node, pinId, isOutput] = mWorkflow->DisassembleGlobalPinId((size_t)newNodePin);
+
+				if ((isOutput && node->GetOutputPin(pinId).IsConnected()) ||
+					(!isOutput && node->GetInputPin(pinId).IsConnected()))
+				{
+					ImNodes::RejectNewItem();
+					goto createError;
+				}
+
+				if (ImNodes::AcceptNewItem()) {
+					ImNodes::Suspend();
+					ImGui::BeginPopup("Create Node");
+					ImNodes::Resume();
+				}
+			}
+		}
+	createError:
+		ImNodes::EndCreate();
+
+		if (ImNodes::BeginDelete()) {
+			ImNodes::LinkId deletedLinkId;
+			if (ImNodes::QueryDeletedLink(&deletedLinkId)) {
+				// Link id is the same as our connection id
+				auto& conn = *mWorkflow->GetConnectionById((size_t)deletedLinkId);
+
+				// TODO
+			}
+		}
+	deleteError:
+		ImNodes::EndDelete();
+
+		// Popups
+		ImNodes::Suspend();
+		if (ImGui::BeginPopup("Node Context Menu")) {
+			// TODO
+			ImGui::EndPopup();
+		}
+		if (ImGui::BeginPopup("Link Context Menu")) {
+			// TODO
+			ImGui::EndPopup();
+		}
+		if (ImGui::BeginPopup("Create Node")) {
+			auto DisplayCandidatesCategory = [&](const char* name, std::span<const WorkflowDatabase::Candidate> candidates) {
+				ImGui::TreeNode(name);
+				for (auto& candidate : candidates) {
+					if (ImGui::MenuItem(candidate.Name.c_str())) {
+						// TODO
+					}
+				}
+				ImGui::TreePop();
+			};
+
+			DisplayCandidatesCategory("Numeric nodes", mWorkflowDatabase.GetNumericNodes());
+			DisplayCandidatesCategory("Text nodes", mWorkflowDatabase.GetTextNodes());
+			DisplayCandidatesCategory("Document nodes", mWorkflowDatabase.GetDocumentNodes());
+			DisplayCandidatesCategory("User input nodes", mWorkflowDatabase.GetUserInputNodes());
+			DisplayCandidatesCategory("System input nodes", mWorkflowDatabase.GetSystemInputNodes());
+			DisplayCandidatesCategory("Output nodes", mWorkflowDatabase.GetOutputNodes());
+			ImGui::EndPopup();
+		}
+		if (tooltipMessage) {
+			ImGui::BeginTooltip();
+			ImGui::TextUnformatted(tooltipMessage);
+			ImGui::EndTooltip();
 		}
+		ImNodes::Resume();
 
 		ImNodes::End();
 	}
-- 
cgit v1.2.3-70-g09d2