--- a/src/bridge_gui.cpp	Sat May 17 21:20:58 2008 +0000
+++ b/src/bridge_gui.cpp	Sat May 17 22:07:04 2008 +0000
@@ -17,37 +17,34 @@
 #include "viewport_func.h"
 #include "gfx_func.h"
 #include "tunnelbridge.h"
+#include "sortlist_type.h"
 
 #include "table/strings.h"
 
-static struct BridgeData {
-	uint8 last_size;
-	uint count;
-	TileIndex start_tile;
-	TileIndex end_tile;
-	uint32 type; ///< Data type for the bridge. Bit 16,15 = transport type, 14..8 = road/rail pieces, 7..0 = type of bridge
-	BridgeType indexes[MAX_BRIDGES];
-	Money costs[MAX_BRIDGES];
+/**
+ * Carriage for the data we need if we want to build a bridge
+ */
+struct BuildBridgeData {
+	BridgeType index;
+	const BridgeSpec *spec;
+	Money cost;
+};
 
-	BridgeData()
-		: last_size(4)
-		, count(0)
-		{};
-} _bridgedata;
+typedef GUIList<BuildBridgeData> GUIBridgeList;
 
+/**
+ * Callback executed after a build Bridge CMD has been called
+ *
+ * @param scucess True if the build succeded
+ * @param tile The tile where the command has been executed
+ * @param p1 not used
+ * @param p2 not used
+ */
 void CcBuildBridge(bool success, TileIndex tile, uint32 p1, uint32 p2)
 {
 	if (success) SndPlayTileFx(SND_27_BLACKSMITH_ANVIL, tile);
 }
 
-static void BuildBridge(Window *w, int i)
-{
-	delete w;
-	DoCommandP(_bridgedata.end_tile, _bridgedata.start_tile,
-		_bridgedata.type | _bridgedata.indexes[i], CcBuildBridge,
-		CMD_BUILD_BRIDGE | CMD_MSG(STR_5015_CAN_T_BUILD_BRIDGE_HERE));
-}
-
 /* Names of the build bridge selection window */
 enum BuildBridgeSelectionWidgets {
 	BBSW_CLOSEBOX = 0,
@@ -57,72 +54,111 @@
 	BBSW_RESIZEBOX
 };
 
-static void BuildBridgeWndProc(Window *w, WindowEvent *e)
-{
-	switch (e->event) {
-		case WE_CREATE:
-			w->resize.step_height = 22;
-			w->vscroll.count = _bridgedata.count;
+class BuildBridgeWindow : public Window {
+private:
+	/* The last size of the build bridge window
+	 * is saved during runtime */
+	static uint8 last_size;
 
-			if (_bridgedata.last_size <= 4) {
-				w->vscroll.cap = 4;
-			} else {
-				/* Resize the bridge selection window if we used a bigger one the last time */
-				w->vscroll.cap = (w->vscroll.count > _bridgedata.last_size) ? _bridgedata.last_size : w->vscroll.count;
-				ResizeWindow(w, 0, (w->vscroll.cap - 4) * w->resize.step_height);
-				w->widget[BBSW_BRIDGE_LIST].data = (w->vscroll.cap << 8) + 1;
-			}
-			break;
-
-		case WE_PAINT: {
-			w->DrawWidgets();
+	TileIndex start_tile;
+	TileIndex end_tile;
+	uint32 type;
+	const GUIBridgeList *bridges;
 
-			uint y = 15;
-			for (uint i = 0; (i < w->vscroll.cap) && ((i + w->vscroll.pos) < _bridgedata.count); i++) {
-				const BridgeSpec *b = GetBridgeSpec(_bridgedata.indexes[i + w->vscroll.pos]);
+	void BuildBridge(uint8 i)
+	{
+		DoCommandP(this->end_tile, this->start_tile, this->type | this->bridges->sort_list[i].index,
+				CcBuildBridge, CMD_BUILD_BRIDGE | CMD_MSG(STR_5015_CAN_T_BUILD_BRIDGE_HERE));
+	}
 
-				SetDParam(2, _bridgedata.costs[i + w->vscroll.pos]);
-				SetDParam(1, b->speed * 10 / 16);
-				SetDParam(0, b->material);
+public:
+	BuildBridgeWindow(const WindowDesc *desc, TileIndex start, TileIndex end, uint32 br_type, const GUIBridgeList *bl) : Window(desc),
+		start_tile(start),
+		end_tile(end),
+		type(br_type),
+		bridges(bl)
+	{
 
-				DrawSprite(b->sprite, b->pal, 3, y);
-				DrawString(44, y, STR_500D, TC_FROMSTRING);
-				y += w->resize.step_height;
-			}
-			break;
+		/* Change the data, or the caption of the gui. Set it to road or rail, accordingly */
+		this->widget[BBSW_CAPTION].data = (GB(this->type, 15, 2) == TRANSPORT_ROAD) ? STR_1803_SELECT_ROAD_BRIDGE : STR_100D_SELECT_RAIL_BRIDGE;
+
+		this->resize.step_height = 22;
+		this->vscroll.count = bl->list_length;
+
+		if (this->last_size <= 4) {
+			this->vscroll.cap = 4;
+		} else {
+			/* Resize the bridge selection window if we used a bigger one the last time */
+			this->vscroll.cap = (this->vscroll.count > this->last_size) ? this->last_size : this->vscroll.count;
+			ResizeWindow(this, 0, (this->vscroll.cap - 4) * this->resize.step_height);
+			this->widget[BBSW_BRIDGE_LIST].data = (this->vscroll.cap << 8) + 1;
 		}
 
-		case WE_KEYPRESS: {
-			const uint8 i = e->we.keypress.keycode - '1';
-			if (i < 9 && i < _bridgedata.count) {
-				e->we.keypress.cont = false;
-				BuildBridge(w, i);
-			}
+		this->FindWindowPlacementAndResize(desc);
+	}
 
-			break;
+	~BuildBridgeWindow()
+	{
+		free(this->bridges->sort_list);
+		delete bridges;
+	}
+
+	virtual void OnPaint()
+	{
+		this->DrawWidgets();
+
+		uint y = 15;
+		for (uint i = 0; (i < this->vscroll.cap) && ((i + this->vscroll.pos) < this->bridges->list_length); i++) {
+			const BridgeSpec *b = this->bridges->sort_list[i + this->vscroll.pos].spec;
+
+			SetDParam(2, this->bridges->sort_list[i + this->vscroll.pos].cost);
+			SetDParam(1, b->speed * 10 / 16);
+			SetDParam(0, b->material);
+
+			DrawSprite(b->sprite, b->pal, 3, y);
+			DrawString(44, y, STR_500D, TC_FROMSTRING);
+			y += this->resize.step_height;
 		}
+	}
 
-		case WE_CLICK:
-			if (e->we.click.widget == BBSW_BRIDGE_LIST) {
-				uint ind = ((int)e->we.click.pt.y - 14) / w->resize.step_height;
-				if (ind < w->vscroll.cap) {
-					ind += w->vscroll.pos;
-					if (ind < _bridgedata.count) {
-						BuildBridge(w, ind);
-					}
+	virtual bool OnKeyPress(uint16 key, uint16 keycode)
+	{
+		const uint8 i = keycode - '1';
+		if (i < 9 && i < this->bridges->list_length) {
+			/* Build the requested bridge */
+			this->BuildBridge(i);
+			delete this;
+			return false;
+		}
+		return true;
+	}
+
+	virtual void OnClick(Point pt, int widget)
+	{
+		if (widget == BBSW_BRIDGE_LIST) {
+			uint i = ((int)pt.y - 14) / this->resize.step_height;
+			if (i < this->vscroll.cap) {
+				i += this->vscroll.pos;
+				if (i < this->bridges->list_length) {
+					this->BuildBridge(i);
+					delete this;
 				}
 			}
-			break;
+		}
+	}
 
-		case WE_RESIZE:
-			w->vscroll.cap += e->we.sizing.diff.y / (int)w->resize.step_height;
-			w->widget[BBSW_BRIDGE_LIST].data = (w->vscroll.cap << 8) + 1;
-			SetVScrollCount(w, _bridgedata.count);
+	virtual void OnResize(Point new_size, Point delta)
+	{
+		this->vscroll.cap += delta.y / (int)this->resize.step_height;
+		this->widget[BBSW_BRIDGE_LIST].data = (this->vscroll.cap << 8) + 1;
+		SetVScrollCount(this, this->bridges->list_length);
 
-			_bridgedata.last_size = w->vscroll.cap;
-			break;
+		this->last_size = this->vscroll.cap;
 	}
-}
+};
+
+/* Set the default size of the Build Bridge Window */
+uint8 BuildBridgeWindow::last_size = 4;
 
 /* Widget definition for the rail bridge selection window */
 static const Widget _build_bridge_widgets[] = {
@@ -140,23 +176,62 @@
 	WC_BUILD_BRIDGE, WC_BUILD_TOOLBAR,
 	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_RESIZABLE,
 	_build_bridge_widgets,
-	BuildBridgeWndProc
+	NULL
 };
 
+/**
+ * Add a buildable bridge to the list.
+ *  If the list is empty a new one is created.
+ *
+ * @param bl The list which we want to manage
+ * @param item The item to add
+ * @return The pointer to the list
+ */
+static GUIBridgeList *PushBridgeList(GUIBridgeList *bl, BuildBridgeData item)
+{
+	if (bl == NULL) {
+		/* Create the list if needed */
+		bl = new GUIBridgeList();
+		bl->flags |= VL_RESORT;
+		bl->list_length = 1;
+	} else {
+		/* Resize the list */
+		bl->list_length++;
+	}
+
+	bl->sort_list = ReallocT(bl->sort_list, bl->list_length);
+
+	bl->sort_list[bl->list_length - 1] = item;
+
+	return bl;
+}
+
+/**
+ * Prepare the data for the build a bridge window.
+ *  If we can't build a bridge under the given conditions
+ *  show an error message.
+ *
+ * @parma start The start tile of the bridge
+ * @param end The end tile of the bridge
+ * @param transport_type The transport type
+ * @param bridge_type The bridge type
+ */
 void ShowBuildBridgeWindow(TileIndex start, TileIndex end, TransportType transport_type, byte bridge_type)
 {
 	DeleteWindowById(WC_BUILD_BRIDGE, 0);
 
-	_bridgedata.type = (transport_type << 15) | (bridge_type << 8); //prepare the parameter for use only once
-	_bridgedata.start_tile = start;
-	_bridgedata.end_tile = end;
+	/* Data type for the bridge.
+	 * Bit 16,15 = transport type,
+	 *     14..8 = road/rail pieces,
+	 *      7..0 = type of bridge */
+	uint32 type = (transport_type << 15) | (bridge_type << 8);
 
 	/* only query bridge building possibility once, result is the same for all bridges!
 	 * returns CMD_ERROR on failure, and price on success */
 	StringID errmsg = INVALID_STRING_ID;
-	CommandCost ret = DoCommand(end, start, _bridgedata.type, DC_AUTO | DC_QUERY_COST, CMD_BUILD_BRIDGE);
+	CommandCost ret = DoCommand(end, start, type, DC_AUTO | DC_QUERY_COST, CMD_BUILD_BRIDGE);
 
-	uint8 j = 0;
+	GUIBridgeList *bl = NULL;
 	if (CmdFailed(ret)) {
 		errmsg = _error_message;
 	} else {
@@ -171,22 +246,19 @@
 		for (BridgeType brd_type = 0; brd_type != MAX_BRIDGES; brd_type++) {
 			if (CheckBridge_Stuff(brd_type, bridge_len)) {
 				/* bridge is accepted, add to list */
-				const BridgeSpec *b = GetBridgeSpec(brd_type);
+				BuildBridgeData item;
+				item.index = brd_type;
+				item.spec = GetBridgeSpec(brd_type);
 				/* Add to terraforming & bulldozing costs the cost of the
 				 * bridge itself (not computed with DC_QUERY_COST) */
-				_bridgedata.costs[j] = ret.GetCost() + (((int64)tot_bridgedata_len * _price.build_bridge * b->price) >> 8);
-				_bridgedata.indexes[j] = brd_type;
-				j++;
+				item.cost = ret.GetCost() + (((int64)tot_bridgedata_len * _price.build_bridge * item.spec->price) >> 8);
+				bl = PushBridgeList(bl, item);
 			}
 		}
-
-		_bridgedata.count = j;
 	}
 
-	if (j != 0) {
-		Window *w = new Window(&_build_bridge_desc);
-		/* Change the data, or the caption of the gui. Set it to road or rail, accordingly */
-		w->widget[BBSW_CAPTION].data = (transport_type == TRANSPORT_ROAD) ? STR_1803_SELECT_ROAD_BRIDGE : STR_100D_SELECT_RAIL_BRIDGE;
+	if (bl != NULL) {
+		new BuildBridgeWindow(&_build_bridge_desc, start, end, type, bl);
 	} else {
 		ShowErrorMessage(errmsg, STR_5015_CAN_T_BUILD_BRIDGE_HERE, TileX(end) * TILE_SIZE, TileY(end) * TILE_SIZE);
 	}