[nostalgia/gfx/studio/tilesheet] Add the ability to move subsheets

src/nostalgia/modules/gfx/include/nostalgia/gfx/tilesheet.hpp

@@ -289,7 +289,7 @@ constexpr ox::Error repair(TileSheetV4 &ts) noexcept {
 
 
 struct TileSheetV5 {
-	using SubSheetIdx = ox::Vector<std::size_t, 4>;
+	using SubSheetIdx = ox::Vector<uint32_t, 4>;
 
 	struct SubSheet {
 		static constexpr auto TypeName = "net.drinkingtea.nostalgia.gfx.TileSheet.SubSheet";
@@ -445,23 +445,25 @@ TileSheet::SubSheetIdx validateSubSheetIdx(TileSheet const&ts, TileSheet::SubShe
 
 [[nodiscard]]
 TileSheet::SubSheet const&getSubSheet(
-		TileSheet::SubSheetIdx const&idx,
+		ox::SpanView<uint32_t> const&idx,
 		std::size_t idxIt,
 		TileSheet::SubSheet const&pSubsheet) noexcept;
 
 [[nodiscard]]
 TileSheet::SubSheet &getSubSheet(
-		TileSheet::SubSheetIdx const&idx,
+		ox::SpanView<uint32_t> const&idx,
 		std::size_t idxIt,
 		TileSheet::SubSheet &pSubsheet) noexcept;
 
 [[nodiscard]]
-TileSheet::SubSheet const&getSubSheet(TileSheet const&ts, TileSheet::SubSheetIdx const&idx) noexcept;
+TileSheet::SubSheet const&getSubSheet(TileSheet const&ts, ox::SpanView<uint32_t> const &idx) noexcept;
 
 [[nodiscard]]
-TileSheet::SubSheet &getSubSheet(TileSheet &ts, TileSheet::SubSheetIdx const&idx) noexcept;
+TileSheet::SubSheet &getSubSheet(TileSheet &ts, ox::SpanView<uint32_t> const &idx) noexcept;
 
-ox::Error addSubSheet(TileSheet &ts, TileSheet::SubSheetIdx const&idx) noexcept;
+ox::Error addSubSheet(TileSheet &ts, TileSheet::SubSheetIdx const &idx) noexcept;
+
+ox::Error insertSubSheet(TileSheet &ts, ox::SpanView<uint32_t> const &idx, TileSheet::SubSheet ss) noexcept;
 
 ox::Error rmSubSheet(
 		TileSheet &ts,

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/commands/CMakeLists.txt

@@ -5,6 +5,7 @@ target_sources(
 		deletetilescommand.cpp
 		drawcommand.cpp
 		flipcommand.cpp
+		movesubsheetcommand.cpp
 		inserttilescommand.cpp
 		palettechangecommand.cpp
 		rmsubsheetcommand.cpp

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/commands/commands.hpp

@@ -15,9 +15,10 @@ enum class CommandId {
 	AddSubSheet,
 	RmSubSheet,
 	DeleteTile,
-	FlipXCommand,
+	FlipX,
-	FlipYCommand,
+	FlipY,
 	InsertTile,
+	MoveSubSheet,
 	UpdateSubSheet,
 	Cut,
 	Paste,

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/commands/flipcommand.cpp

@@ -31,7 +31,7 @@ ox::Error FlipXCommand::undo() noexcept {
 }
 
 int FlipXCommand::commandId() const noexcept {
-	return static_cast<int>(CommandId::FlipXCommand);
+	return static_cast<int>(CommandId::FlipX);
 }
 
 TileSheet::SubSheetIdx const &FlipXCommand::subsheetIdx() const noexcept {
@@ -62,7 +62,7 @@ ox::Error FlipYCommand::undo() noexcept {
 }
 
 int FlipYCommand::commandId() const noexcept {
-	return static_cast<int>(CommandId::FlipYCommand);
+	return static_cast<int>(CommandId::FlipY);
 }
 
 TileSheet::SubSheetIdx const &FlipYCommand::subsheetIdx() const noexcept {

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/commands/movesubsheetcommand.cpp

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2016 - 2025 Gary Talent (gary@drinkingtea.net). All rights reserved.
+ */
+
+#include "movesubsheetcommand.hpp"
+
+namespace nostalgia::gfx {
+
+MoveSubSheetCommand::MoveSubSheetCommand(
+	TileSheet &img,
+	TileSheet::SubSheetIdx src,
+	TileSheet::SubSheetIdx dst) noexcept:
+		m_img{img},
+		m_src{std::move(src)},
+		m_dst{std::move(dst)} {
+}
+
+ox::Error MoveSubSheetCommand::redo() noexcept {
+	m_active = &m_dst;
+	TileSheet::SubSheet ss = std::move(getSubSheet(m_img, m_src));
+	OX_RETURN_ERROR(rmSubSheet(m_img, m_src));
+	return insertSubSheet(m_img, m_dst, std::move(ss));
+}
+
+ox::Error MoveSubSheetCommand::undo() noexcept {
+	m_active = &m_src;
+	TileSheet::SubSheet ss = std::move(getSubSheet(m_img, m_dst));
+	OX_RETURN_ERROR(rmSubSheet(m_img, m_dst));
+	return insertSubSheet(m_img, m_src, std::move(ss));
+}
+
+int MoveSubSheetCommand::commandId() const noexcept {
+	return static_cast<int>(CommandId::MoveSubSheet);
+}
+
+TileSheet::SubSheetIdx const&MoveSubSheetCommand::subsheetIdx() const noexcept {
+	return *m_active;
+}
+
+}

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/commands/movesubsheetcommand.hpp

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2016 - 2025 Gary Talent (gary@drinkingtea.net). All rights reserved.
+ */
+
+#pragma once
+
+#include "commands.hpp"
+
+namespace nostalgia::gfx {
+
+class MoveSubSheetCommand: public TileSheetCommand {
+	private:
+		TileSheet &m_img;
+		TileSheet::SubSheetIdx m_src;
+		TileSheet::SubSheetIdx m_dst;
+		TileSheet::SubSheetIdx *m_active = &m_dst;
+
+	public:
+		MoveSubSheetCommand(TileSheet &img, TileSheet::SubSheetIdx src, TileSheet::SubSheetIdx dst) noexcept;
+
+		ox::Error redo() noexcept final;
+
+		ox::Error undo() noexcept final;
+
+		[[nodiscard]]
+		int commandId() const noexcept final;
+
+		[[nodiscard]]
+		TileSheet::SubSheetIdx const&subsheetIdx() const noexcept override;
+
+};
+
+}

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/tilesheeteditor-imgui.cpp

@@ -15,6 +15,16 @@ namespace nostalgia::gfx {
 
 namespace ig = studio::ig;
 
+struct SubSheetRef {
+	static constexpr auto TypeName = "nostalgia.gfx.studio.SubSheetRef";
+	static constexpr auto TypeVersion = 1;
+	TileSheet::SubSheetIdx subsheet{};
+};
+
+OX_MODEL_BEGIN(SubSheetRef)
+	OX_MODEL_FIELD(subsheet)
+OX_MODEL_END()
+
 struct TileSheetEditorConfig {
 	static constexpr auto TypeName = "net.drinkingtea.nostalgia.gfx.studio.TileSheetEditorConfig";
 	static constexpr auto TypeVersion = 1;
@@ -309,6 +319,16 @@ void TileSheetEditorImGui::drawSubsheetSelector(
 	                 | (rowSelected ? ImGuiTreeNodeFlags_Selected : 0);
 	ImGui::TableNextColumn();
 	auto const open = ImGui::TreeNodeEx(lbl.c_str(), flags);
+	std::ignore = ig::dragDropSource([&subsheet, &path] {
+		ImGui::Text("%s", subsheet.name.c_str());
+		return ig::setDragDropPayload(SubSheetRef{path});
+	});
+	if (ig::DragDropTarget const dragDropTarget; dragDropTarget) {
+		auto const [ref, err] = ig::getDragDropPayload<SubSheetRef>();
+		if (!err) {
+			oxLogError(m_model.moveSubSheet(ref.subsheet, path));
+		}
+	}
 	ImGui::SameLine();
 	if (ImGui::IsItemClicked()) {
 		setActiveSubsheet(path);
@@ -330,7 +350,7 @@ void TileSheetEditorImGui::drawSubsheetSelector(
 		ImGui::Text("--");
 	}
 	if (open) {
-		for (auto i = 0ul; auto &child : subsheet.subsheets) {
+		for (uint32_t i{}; auto &child : subsheet.subsheets) {
 			path.push_back(i);
 			ImGui::PushID(static_cast<int>(i));
 			ig::IndentStackItem	const indentStackItem{-indentReduce};

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/tilesheeteditor-imgui.hpp

@@ -58,6 +58,7 @@ class TileSheetEditorImGui: public studio::Editor {
 		ox::Vec2 m_prevMouseDownPos;
 		TileSheetTool m_tool = TileSheetTool::Draw;
 		bool m_palPathFocused{};
+		ox::Vector<ox::UPtr<studio::UndoCommand>, 1> m_deferredCmds;
 
 	public:
 		TileSheetEditorImGui(studio::StudioContext &sctx, ox::StringParam path);

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/tilesheeteditormodel.cpp

@@ -11,18 +11,19 @@
 
 #include <nostalgia/gfx/ptidxconv.hpp>
 
-#include "commands/commands.hpp"
 #include "commands/addsubsheetcommand.hpp"
+#include "commands/commands.hpp"
 #include "commands/cutpastecommand.hpp"
 #include "commands/deletetilescommand.hpp"
 #include "commands/drawcommand.hpp"
+#include "commands/flipcommand.hpp"
 #include "commands/inserttilescommand.hpp"
 #include "commands/palettechangecommand.hpp"
 #include "commands/rmsubsheetcommand.hpp"
 #include "commands/updatesubsheetcommand.hpp"
 #include "tilesheeteditormodel.hpp"
 
-#include "commands/flipcommand.hpp"
+#include "commands/movesubsheetcommand.hpp"
 
 namespace nostalgia::gfx {
 
@@ -303,6 +304,10 @@ ox::Error TileSheetEditorModel::flipY() noexcept {
 	return pushCommand(ox::make<FlipYCommand>(m_img, m_activeSubsSheetIdx, a, b));
 }
 
+ox::Error TileSheetEditorModel::moveSubSheet(TileSheet::SubSheetIdx src, TileSheet::SubSheetIdx dst) noexcept {
+	return pushCommand(ox::make<MoveSubSheetCommand>(m_img, std::move(src), std::move(dst)));
+}
+
 void TileSheetEditorModel::getFillPixels(
 		TileSheet::SubSheet const&activeSubSheet,
 		ox::Span<bool> pixels,

src/nostalgia/modules/gfx/src/studio/tilesheeteditor/tilesheeteditormodel.hpp

@@ -130,6 +130,8 @@ class TileSheetEditorModel: public ox::SignalHandler {
 
 		ox::Error flipY() noexcept;
 
+		ox::Error moveSubSheet(TileSheet::SubSheetIdx src, TileSheet::SubSheetIdx dst) noexcept;
+
 	private:
 		void getFillPixels(
 			TileSheet::SubSheet const&activeSubSheet,

src/nostalgia/modules/gfx/src/tilesheet.cpp

@@ -177,7 +177,7 @@ TileSheet::SubSheetIdx validateSubSheetIdx(
 			pIdx.resize(pIdxIt);
 			return std::move(pIdx);
 		} else {
-			currentIdx = pSubsheet.subsheets.size() - 1;
+			currentIdx = static_cast<uint32_t>(pSubsheet.subsheets.size() - 1);
 		}
 	}
 	return validateSubSheetIdx(std::move(pIdx), pIdxIt + 1, pSubsheet.subsheets[currentIdx]);
@@ -188,9 +188,9 @@ TileSheet::SubSheetIdx validateSubSheetIdx(TileSheet const&ts, TileSheet::SubShe
 }
 
 TileSheet::SubSheet const&getSubSheet(
-		TileSheet::SubSheetIdx const&idx,
+		ox::SpanView<uint32_t> const &idx,
 		std::size_t const idxIt,
-		TileSheet::SubSheet const&pSubsheet) noexcept {
+		TileSheet::SubSheet const &pSubsheet) noexcept {
 	if (idxIt == idx.size()) {
 		return pSubsheet;
 	}
@@ -202,7 +202,7 @@ TileSheet::SubSheet const&getSubSheet(
 }
 
 TileSheet::SubSheet &getSubSheet(
-		TileSheet::SubSheetIdx const&idx,
+		ox::SpanView<uint32_t> const &idx,
 		std::size_t const idxIt,
 		TileSheet::SubSheet &pSubsheet) noexcept {
 	if (idxIt == idx.size()) {
@@ -211,11 +211,11 @@ TileSheet::SubSheet &getSubSheet(
 	return getSubSheet(idx, idxIt + 1, pSubsheet.subsheets[idx[idxIt]]);
 }
 
-TileSheet::SubSheet const&getSubSheet(TileSheet const&ts, TileSheet::SubSheetIdx const&idx) noexcept {
+TileSheet::SubSheet const&getSubSheet(TileSheet const &ts, ox::SpanView<uint32_t> const &idx) noexcept {
 	return gfx::getSubSheet(idx, 0, ts.subsheet);
 }
 
-TileSheet::SubSheet &getSubSheet(TileSheet &ts, TileSheet::SubSheetIdx const&idx) noexcept {
+TileSheet::SubSheet &getSubSheet(TileSheet &ts, ox::SpanView<uint32_t> const&idx) noexcept {
 	return gfx::getSubSheet(idx, 0, ts.subsheet);
 }
 
@@ -227,7 +227,20 @@ ox::Error addSubSheet(TileSheet &ts, TileSheet::SubSheetIdx const&idx) noexcept
 		parent.subsheets.emplace_back(++ts.idIt, "Subsheet 0", parent.columns, parent.rows);
 		parent.subsheets.emplace_back(++ts.idIt, "Subsheet 1", 1, 1);
 	}
-	return ox::Error(0);
+	return {};
+}
+
+ox::Error insertSubSheet(TileSheet &ts, ox::SpanView<uint32_t> const&idx, TileSheet::SubSheet ss) noexcept {
+	if (idx.empty()) {
+		return ox::Error{1, "invalid insert idx"};
+	}
+	auto &parent = getSubSheet(ts, {idx.data(), idx.size() - 1});
+	auto const insertIdx = idx[idx.size() - 1];
+	if (insertIdx > parent.subsheets.size()) {
+		return ox::Error{1, "invalid insert idx"};
+	}
+	parent.subsheets.emplace(insertIdx, std::move(ss));
+	return {};
 }
 
 ox::Error rmSubSheet(