Add support for adding a third error line to the error GUI

Add support for a second error string ID to CommandCost

src/command.cpp

@@ -785,7 +785,7 @@ bool DoCommandP(TileIndex tile, uint32 p1, uint32 p2, uint32 cmd, CommandCallbac
 		/* Only show the error when it's for us. */
 		StringID error_part1 = GB(cmd, 16, 16);
 		if (estimate_only || (IsLocalCompany() && error_part1 != 0 && my_cmd)) {
-			ShowErrorMessage(error_part1, res.GetErrorMessage(), WL_INFO, x, y, res.GetTextRefStackGRF(), res.GetTextRefStackSize(), res.GetTextRefStack());
+			ShowErrorMessage(error_part1, res.GetErrorMessage(), WL_INFO, x, y, res.GetTextRefStackGRF(), res.GetTextRefStackSize(), res.GetTextRefStack(), res.GetExtraErrorMessage());
 		}
 	} else if (estimate_only) {
 		ShowEstimatedCostOrIncome(res.GetCost(), x, y);

src/command_type.h

@@ -30,6 +30,7 @@ class CommandCost {
 	bool success;     ///< Whether the comment went fine up to this moment
 	const GRFFile *textref_stack_grffile; ///< NewGRF providing the #TextRefStack content.
 	uint textref_stack_size;   ///< Number of uint32 values to put on the #TextRefStack for the error message.
+	StringID extra_message = INVALID_STRING_ID;    ///< Additional warning message for when success is unset
 
 	static uint32 textref_stack[16];
 
@@ -44,6 +45,16 @@ public:
 	 */
 	explicit CommandCost(StringID msg) : expense_type(INVALID_EXPENSES), cost(0), message(msg), success(false), textref_stack_grffile(NULL), textref_stack_size(0) {}
 
+	/**
+	 * Creates a command return value the is failed with the given message
+	 */
+	static CommandCost DualErrorMessage(StringID msg, StringID extra_msg)
+	{
+		CommandCost cc(msg);
+		cc.extra_message = extra_msg;
+		return cc;
+	}
+
 	/**
 	 * Creates a command cost with given expense type and start cost of 0
 	 * @param ex_t the expense type
@@ -100,11 +111,12 @@ public:
 	 * Makes this #CommandCost behave like an error command.
 	 * @param message The error message.
 	 */
-	void MakeError(StringID message)
+	void MakeError(StringID message, StringID extra_message = INVALID_STRING_ID)
 	{
 		assert(message != INVALID_STRING_ID);
 		this->success = false;
 		this->message = message;
+		this->extra_message = extra_message;
 	}
 
 	void UseTextRefStack(const GRFFile *grffile, uint num_registers);
@@ -146,6 +158,16 @@ public:
 		return this->message;
 	}
 
+	/**
+	 * Returns the extra error message of a command
+	 * @return the extra error message, if succeeded #INVALID_STRING_ID
+	 */
+	StringID GetExtraErrorMessage() const
+	{
+		if (this->success) return INVALID_STRING_ID;
+		return this->extra_message;
+	}
+
 	/**
 	 * Did this command succeed?
 	 * @return true if and only if it succeeded

src/error.h

@@ -37,13 +37,14 @@ protected:
 	uint32 textref_stack[16];       ///< Values to put on the #TextRefStack for the error message.
 	StringID summary_msg;           ///< General error message showed in first line. Must be valid.
 	StringID detailed_msg;          ///< Detailed error message showed in second line. Can be #INVALID_STRING_ID.
+	StringID extra_msg;             ///< Extra error message shown in third line. Can be #INVALID_STRING_ID.
 	Point position;                 ///< Position of the error message window.
 	CompanyID face;                 ///< Company belonging to the face being shown. #INVALID_COMPANY if no face present.
 
 public:
 	ErrorMessageData(const ErrorMessageData &data);
 	~ErrorMessageData();
-	ErrorMessageData(StringID summary_msg, StringID detailed_msg, uint duration = 0, int x = 0, int y = 0, const GRFFile *textref_stack_grffile = NULL, uint textref_stack_size = 0, const uint32 *textref_stack = NULL);
+	ErrorMessageData(StringID summary_msg, StringID detailed_msg, uint duration = 0, int x = 0, int y = 0, const GRFFile *textref_stack_grffile = NULL, uint textref_stack_size = 0, const uint32 *textref_stack = NULL, StringID extra_msg = INVALID_STRING_ID);
 
 	/** Check whether error window shall display a company manager face */
 	bool HasFace() const { return face != INVALID_COMPANY; }
@@ -56,7 +57,7 @@ public:
 
 void ScheduleErrorMessage(const ErrorMessageData &data);
 
-void ShowErrorMessage(StringID summary_msg, StringID detailed_msg, WarningLevel wl, int x = 0, int y = 0, const GRFFile *textref_stack_grffile = NULL, uint textref_stack_size = 0, const uint32 *textref_stack = NULL);
+void ShowErrorMessage(StringID summary_msg, StringID detailed_msg, WarningLevel wl, int x = 0, int y = 0, const GRFFile *textref_stack_grffile = NULL, uint textref_stack_size = 0, const uint32 *textref_stack = NULL, StringID extra_msg = INVALID_STRING_ID);
 void ClearErrorMessages();
 void ShowFirstError();
 void UnshowCriticalError();

src/error_gui.cpp

@@ -99,13 +99,15 @@ ErrorMessageData::~ErrorMessageData()
  * @param textref_stack_grffile NewGRF that provides the #TextRefStack for the error message.
  * @param textref_stack_size Number of uint32 values to put on the #TextRefStack for the error message; 0 if the #TextRefStack shall not be used.
  * @param textref_stack Values to put on the #TextRefStack.
+ * @param extra_msg    Extra error message showed in third line. Can be INVALID_STRING_ID.
  */
-ErrorMessageData::ErrorMessageData(StringID summary_msg, StringID detailed_msg, uint duration, int x, int y, const GRFFile *textref_stack_grffile, uint textref_stack_size, const uint32 *textref_stack) :
+ErrorMessageData::ErrorMessageData(StringID summary_msg, StringID detailed_msg, uint duration, int x, int y, const GRFFile *textref_stack_grffile, uint textref_stack_size, const uint32 *textref_stack, StringID extra_msg) :
 	duration(duration),
 	textref_stack_grffile(textref_stack_grffile),
 	textref_stack_size(textref_stack_size),
 	summary_msg(summary_msg),
 	detailed_msg(detailed_msg),
+	extra_msg(extra_msg),
 	face(INVALID_COMPANY)
 {
 	this->position.x = x;
@@ -173,6 +175,7 @@ struct ErrmsgWindow : public Window, ErrorMessageData {
 private:
 	uint height_summary;            ///< Height of the #summary_msg string in pixels in the #WID_EM_MESSAGE widget.
 	uint height_detailed;           ///< Height of the #detailed_msg string in pixels in the #WID_EM_MESSAGE widget.
+	uint height_extra;              ///< Height of the #extra_msg string in pixels in the #WID_EM_MESSAGE widget.
 
 public:
 	ErrmsgWindow(const ErrorMessageData &data) : Window(data.HasFace() ? &_errmsg_face_desc : &_errmsg_desc), ErrorMessageData(data)
@@ -190,11 +193,13 @@ public:
 				int text_width = max(0, (int)size->width - WD_FRAMETEXT_LEFT - WD_FRAMETEXT_RIGHT);
 				this->height_summary = GetStringHeight(this->summary_msg, text_width);
 				this->height_detailed = (this->detailed_msg == INVALID_STRING_ID) ? 0 : GetStringHeight(this->detailed_msg, text_width);
+				this->height_extra = (this->extra_msg == INVALID_STRING_ID) ? 0 : GetStringHeight(this->extra_msg, text_width);
 
 				if (this->textref_stack_size > 0) StopTextRefStackUsage();
 
 				uint panel_height = WD_FRAMERECT_TOP + this->height_summary + WD_FRAMERECT_BOTTOM;
 				if (this->detailed_msg != INVALID_STRING_ID) panel_height += this->height_detailed + WD_PAR_VSEP_WIDE;
+				if (this->extra_msg != INVALID_STRING_ID) panel_height += this->height_extra + WD_PAR_VSEP_WIDE;
 
 				size->height = max(size->height, panel_height);
 				break;
@@ -271,7 +276,7 @@ public:
 				if (this->detailed_msg == INVALID_STRING_ID) {
 					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, r.top + WD_FRAMERECT_TOP, r.bottom - WD_FRAMERECT_BOTTOM,
 							this->summary_msg, TC_FROMSTRING, SA_CENTER);
-				} else {
+				} else if (this->extra_msg == INVALID_STRING_ID) {
 					int extra = (r.bottom - r.top + 1 - this->height_summary - this->height_detailed - WD_PAR_VSEP_WIDE) / 2;
 
 					/* Note: NewGRF supplied error message often do not start with a colour code, so default to white. */
@@ -282,6 +287,21 @@ public:
 					bottom = r.bottom - WD_FRAMERECT_BOTTOM;
 					top = bottom - this->height_detailed - extra;
 					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->detailed_msg, TC_WHITE, SA_CENTER);
+				} else {
+					int extra = (r.bottom - r.top + 1 - this->height_summary - this->height_detailed - this->height_extra - (WD_PAR_VSEP_WIDE * 2)) / 3;
+
+					/* Note: NewGRF supplied error message often do not start with a colour code, so default to white. */
+					int top = r.top + WD_FRAMERECT_TOP;
+					int bottom = top + this->height_summary + extra;
+					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->summary_msg, TC_WHITE, SA_CENTER);
+
+					top = bottom + WD_PAR_VSEP_WIDE;
+					bottom = top + this->height_detailed + extra;
+					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->detailed_msg, TC_WHITE, SA_CENTER);
+
+					bottom = r.bottom - WD_FRAMERECT_BOTTOM;
+					top = bottom - this->height_extra - extra;
+					DrawStringMultiLine(r.left + WD_FRAMETEXT_LEFT, r.right - WD_FRAMETEXT_RIGHT, top, bottom, this->extra_msg, TC_WHITE, SA_CENTER);
 				}
 
 				if (this->textref_stack_size > 0) StopTextRefStackUsage();
@@ -374,8 +394,9 @@ void UnshowCriticalError()
  * @param textref_stack_grffile NewGRF providing the #TextRefStack for the error message.
  * @param textref_stack_size Number of uint32 values to put on the #TextRefStack for the error message; 0 if the #TextRefStack shall not be used.
  * @param textref_stack Values to put on the #TextRefStack.
+ * @param extra_msg    Extra error message showed in third line. Can be INVALID_STRING_ID.
  */
-void ShowErrorMessage(StringID summary_msg, StringID detailed_msg, WarningLevel wl, int x, int y, const GRFFile *textref_stack_grffile, uint textref_stack_size, const uint32 *textref_stack)
+void ShowErrorMessage(StringID summary_msg, StringID detailed_msg, WarningLevel wl, int x, int y, const GRFFile *textref_stack_grffile, uint textref_stack_size, const uint32 *textref_stack, StringID extra_msg)
 {
 	assert(textref_stack_size == 0 || (textref_stack_grffile != NULL && textref_stack != NULL));
 	if (summary_msg == STR_NULL) summary_msg = STR_EMPTY;
@@ -391,6 +412,10 @@ void ShowErrorMessage(StringID summary_msg, StringID detailed_msg, WarningLevel
 			b += seprintf(b, lastof(buf), " ");
 			GetString(b, detailed_msg, lastof(buf));
 		}
+		if (extra_msg != INVALID_STRING_ID) {
+			b += seprintf(b, lastof(buf), " ");
+			GetString(b, extra_msg, lastof(buf));
+		}
 
 		if (textref_stack_size > 0) StopTextRefStackUsage();
 
@@ -404,7 +429,7 @@ void ShowErrorMessage(StringID summary_msg, StringID detailed_msg, WarningLevel
 
 	if (_settings_client.gui.errmsg_duration == 0 && !no_timeout) return;
 
-	ErrorMessageData data(summary_msg, detailed_msg, no_timeout ? 0 : _settings_client.gui.errmsg_duration, x, y, textref_stack_grffile, textref_stack_size, textref_stack);
+	ErrorMessageData data(summary_msg, detailed_msg, no_timeout ? 0 : _settings_client.gui.errmsg_duration, x, y, textref_stack_grffile, textref_stack_size, textref_stack, extra_msg);
 	data.CopyOutDParams();
 
 	ErrmsgWindow *w = (ErrmsgWindow*)FindWindowById(WC_ERRMSG, 0);