Add plugin commands NPPM_GETTABCOLORID

No NPPM_SETTABCOLORID though. Plugins can use NPPM_MENUCOMMAND to set current tab color with the desired tab color ID.

Fix #15115, close #15142

PowerEditor/src/MISC/PluginsManager/Notepad_plus_msgs.h

@@ -964,6 +964,27 @@ enum Platform { PF_UNKNOWN, PF_X86, PF_X64, PF_IA64, PF_ARM64 };
 	// if isAllocatedSuccessful is TRUE, and value of idBegin is 7
 	// then indicator ID 7 is preserved by Notepad++, and it is safe to be used by the plugin.
 
+	#define NPPM_GETTABCOLORID (NPPMSG + 114)
+	// int NPPM_GETTABCOLORID (int view, int tabIndex)
+	// Get the tab color id with given view and tab index.
+	// 
+	// wParam[in]: VIEW
+		// Here's the values for the view:
+		//  MAIN_VIEW 0
+		//  SUB_VIEW  1
+		//  active    -1
+	// 
+	// lParam[in]: TABINDEX
+		// Zero-based, i.e., use 0 for first tab, 1 for second tab, etc.; use -1 for active tab
+	//
+	// Return tab color id
+		// tab color id contains the following values:
+		//  -1 (no color)
+		//   0 (yellow)
+		//   1 (green)
+		//   2 (blue)
+		//   3 (orange)
+		//   4 (pink)
 
 	// For RUNCOMMAND_USER
 	#define VAR_NOT_RECOGNIZED 0

PowerEditor/src/NppBigSwitch.cpp

@@ -2953,6 +2953,36 @@ LRESULT Notepad_plus::process(HWND hwnd, UINT message, WPARAM wParam, LPARAM lPa
 			return _pluginsManager.allocateIndicator(static_cast<int32_t>(wParam), reinterpret_cast<int *>(lParam));
 		}
 
+		case NPPM_GETTABCOLORID:
+		{
+			const auto view = static_cast<int>(wParam);
+			auto tabIndex = static_cast<int>(lParam);
+
+			auto colorId = -1;  // no color (or unknown)
+
+			auto pDt = _pDocTab;  // active view
+			if (view == MAIN_VIEW)
+			{
+				pDt = &_mainDocTab;
+			}
+			else if (view == SUB_VIEW)
+			{
+				pDt = &_subDocTab;
+			}
+
+			if (tabIndex == -1)
+			{
+				tabIndex = pDt->getCurrentTabIndex();
+			}
+			
+			if ((tabIndex >= 0) && (tabIndex < static_cast<int>(pDt->nbItem())))
+			{
+				colorId = pDt->getIndividualTabColour(tabIndex);
+			}
+			
+			return colorId;
+		}
+
 		case NPPM_GETBOOKMARKID:
 		{
 			return MARK_BOOKMARK;