Feature: text filter for the industry directory

src/industry_gui.cpp

@@ -38,6 +38,8 @@
 #include "widgets/dropdown_type.h"
 #include "widgets/industry_widget.h"
 #include "clear_map.h"
+#include "querystring_gui.h"
+#include "stringfilter_type.h"
 
 #include "table/strings.h"
 
@@ -1215,7 +1217,7 @@ static const NWidgetPart _nested_industry_directory_widgets[] = {
 				NWidget(WWT_DROPDOWN, COLOUR_BROWN, WID_ID_DROPDOWN_CRITERIA), SetDataTip(STR_JUST_STRING, STR_TOOLTIP_SORT_CRITERIA),
 				NWidget(WWT_DROPDOWN, COLOUR_BROWN, WID_ID_FILTER_BY_ACC_CARGO), SetMinimalSize(225, 12), SetFill(0, 1), SetDataTip(STR_INDUSTRY_DIRECTORY_ACCEPTED_CARGO_FILTER, STR_TOOLTIP_FILTER_CRITERIA),
 				NWidget(WWT_DROPDOWN, COLOUR_BROWN, WID_ID_FILTER_BY_PROD_CARGO), SetMinimalSize(225, 12), SetFill(0, 1), SetDataTip(STR_INDUSTRY_DIRECTORY_PRODUCED_CARGO_FILTER, STR_TOOLTIP_FILTER_CRITERIA),
-				NWidget(WWT_PANEL, COLOUR_BROWN), SetResize(1, 0), EndContainer(),
+				NWidget(WWT_EDITBOX, COLOUR_BROWN, WID_ID_FILTER), SetMinimalSize(96, 0), SetFill(1, 0), SetDataTip(STR_LIST_FILTER_OSKTITLE, STR_LIST_FILTER_TOOLTIP),
 			EndContainer(),
 			NWidget(WWT_PANEL, COLOUR_BROWN, WID_ID_INDUSTRY_LIST), SetDataTip(0x0, STR_INDUSTRY_DIRECTORY_LIST_CAPTION), SetResize(1, 1), SetScrollbar(WID_ID_SCROLLBAR), EndContainer(),
 		EndContainer(),
@@ -1310,6 +1312,10 @@ class IndustryDirectoryWindow : public Window {
 	byte produced_cargo_filter_criteria;        ///< Selected produced cargo filter index
 	byte accepted_cargo_filter_criteria;        ///< Selected accepted cargo filter index
 
+	const int MAX_FILTER_LENGTH = 64;           ///< The max length of the filter, in bytes
+	StringFilter string_filter;                 ///< Filter for industries
+	QueryString industry_editbox;               ///< Filter editbox
+
 	/**
 	 * Set cargo filter list item index.
 	 * @param index The index of the cargo to be set
@@ -1388,11 +1394,18 @@ class IndustryDirectoryWindow : public Window {
 			this->industries.clear();
 
 			for (const Industry *i : Industry::Iterate()) {
-				this->industries.push_back(i);
+				if (this->string_filter.IsEmpty()) {
+					this->industries.push_back(i);
+					continue;
+				}
+				this->string_filter.ResetState();
+				this->string_filter.AddLine(i->GetCachedName());
+				if (this->string_filter.GetState()) this->industries.push_back(i);
 			}
 
 			this->industries.shrink_to_fit();
 			this->industries.RebuildDone();
+			this->vscroll->SetCount((uint)this->industries.size()); // Update scrollbar as well.
 		}
 
 		auto filter = std::make_pair(this->cargo_filter[this->accepted_cargo_filter_criteria],
@@ -1401,8 +1414,6 @@ class IndustryDirectoryWindow : public Window {
 		this->industries.Filter(filter);
 		this->industries.Sort();
 
-		this->vscroll->SetCount((uint)this->industries.size()); // Update scrollbar as well.
-
 		this->SetDirty();
 	}
 
@@ -1544,7 +1555,7 @@ class IndustryDirectoryWindow : public Window {
 	}
 
 public:
-	IndustryDirectoryWindow(WindowDesc *desc, WindowNumber number) : Window(desc)
+	IndustryDirectoryWindow(WindowDesc *desc, WindowNumber number) : Window(desc), industry_editbox(MAX_FILTER_LENGTH)
 	{
 		this->CreateNestedTree();
 		this->vscroll = this->GetScrollbar(WID_ID_SCROLLBAR);
@@ -1555,6 +1566,9 @@ class IndustryDirectoryWindow : public Window {
 		this->BuildSortIndustriesList();
 
 		this->FinishInitNested(0);
+
+		this->querystrings[WID_ID_FILTER] = &this->industry_editbox;
+		this->industry_editbox.cancel_button = QueryString::ACTION_CLEAR;
 	}
 
 	~IndustryDirectoryWindow()
@@ -1720,6 +1734,14 @@ class IndustryDirectoryWindow : public Window {
 		this->vscroll->SetCapacityFromWidget(this, WID_ID_INDUSTRY_LIST);
 	}
 
+	void OnEditboxChanged(int wid) override
+	{
+		if (wid == WID_ID_FILTER) {
+			this->string_filter.SetFilterTerm(this->industry_editbox.text.buf);
+			this->InvalidateData(IDIWD_FORCE_REBUILD);
+		}
+	}
+
 	void OnPaint() override
 	{
 		if (this->industries.NeedRebuild()) this->BuildSortIndustriesList();

src/widgets/industry_widget.h

@@ -37,6 +37,7 @@ enum IndustryDirectoryWidgets {
 	WID_ID_DROPDOWN_CRITERIA,    ///< Dropdown for the criteria of the sort.
 	WID_ID_FILTER_BY_ACC_CARGO,  ///< Accepted cargo filter dropdown list.
 	WID_ID_FILTER_BY_PROD_CARGO, ///< Produced cargo filter dropdown list.
+	WID_ID_FILTER,               ///< Filter of name.
 	WID_ID_INDUSTRY_LIST,        ///< Industry list.
 	WID_ID_SCROLLBAR,            ///< Scrollbar of the list.
 };