Feature: allow to do a hostile takeover of an AI company (in singleplayer) (#10914)

With the removal of the share-system, you could no longer make an
AI disappear in a single player game. At least, not without going
into the console.

src/company_base.h

@@ -165,6 +165,7 @@ struct Company : CompanyProperties, CompanyPool::PoolItem<&_company_pool> {
 };
 
 Money CalculateCompanyValue(const Company *c, bool including_loan = true);
+Money CalculateHostileTakeoverValue(const Company *c);
 
 extern uint _cur_company_tick_index;
 

src/company_cmd.cpp

@@ -709,7 +709,7 @@ static void HandleBankruptcyTakeover(Company *c)
 
 	AI::NewEvent(best->index, new ScriptEventCompanyAskMerger(c->index, c->bankrupt_value));
 	if (IsInteractiveCompany(best->index)) {
-		ShowBuyCompanyDialog(c->index);
+		ShowBuyCompanyDialog(c->index, false);
 	}
 }
 

src/company_func.h

@@ -19,7 +19,7 @@ bool MayCompanyTakeOver(CompanyID cbig, CompanyID small);
 void ChangeOwnershipOfCompanyItems(Owner old_owner, Owner new_owner);
 void GetNameOfOwner(Owner owner, TileIndex tile);
 void SetLocalCompany(CompanyID new_company);
-void ShowBuyCompanyDialog(CompanyID company);
+void ShowBuyCompanyDialog(CompanyID company, bool hostile_takeover);
 void CompanyAdminUpdate(const Company *company);
 void CompanyAdminBankrupt(CompanyID company_id);
 void UpdateLandscapingLimits();

src/company_gui.cpp

@@ -2228,6 +2228,12 @@ static const NWidgetPart _nested_company_widgets[] = {
 					/* Multi player buttons. */
 					NWidget(NWID_VERTICAL), SetPIP(4, 2, 4),
 						NWidget(NWID_SPACER), SetFill(0, 1),
+						NWidget(NWID_HORIZONTAL), SetPIP(0, 4, 0),
+							NWidget(NWID_SPACER), SetFill(1, 0),
+							NWidget(NWID_SELECTION, INVALID_COLOUR, WID_C_SELECT_HOSTILE_TAKEOVER),
+								NWidget(WWT_PUSHTXTBTN, COLOUR_GREY, WID_C_HOSTILE_TAKEOVER), SetDataTip(STR_COMPANY_VIEW_HOSTILE_TAKEOVER_BUTTON, STR_COMPANY_VIEW_HOSTILE_TAKEOVER_TOOLTIP),
+							EndContainer(),
+						EndContainer(),
 						NWidget(NWID_HORIZONTAL), SetPIP(0, 4, 0),
 							NWidget(NWID_SPACER), SetFill(1, 0),
 							NWidget(NWID_SELECTION, INVALID_COLOUR, WID_C_SELECT_GIVE_MONEY),
@@ -2332,6 +2338,13 @@ struct CompanyWindow : Window
 				wi->SetDisplayedPlane(plane);
 				reinit = true;
 			}
+			/* Enable/disable 'Hostile Takeover' button. */
+			plane = ((local || _local_company == COMPANY_SPECTATOR || !c->is_ai || _networking) ? SZSP_NONE : 0);
+			wi = this->GetWidget<NWidgetStacked>(WID_C_SELECT_HOSTILE_TAKEOVER);
+			if (plane != wi->shown_plane) {
+				wi->SetDisplayedPlane(plane);
+				reinit = true;
+			}
 
 			/* Multiplayer buttons. */
 			plane = ((!_networking) ? (int)SZSP_NONE : (int)(local ? CWP_MP_C_PWD : CWP_MP_C_JOIN));
@@ -2398,6 +2411,7 @@ struct CompanyWindow : Window
 			case WID_C_RELOCATE_HQ:
 			case WID_C_VIEW_INFRASTRUCTURE:
 			case WID_C_GIVE_MONEY:
+			case WID_C_HOSTILE_TAKEOVER:
 			case WID_C_COMPANY_PASSWORD:
 			case WID_C_COMPANY_JOIN:
 				size->width = GetStringBoundingBox(STR_COMPANY_VIEW_VIEW_HQ_BUTTON).width;
@@ -2405,6 +2419,7 @@ struct CompanyWindow : Window
 				size->width = std::max(size->width, GetStringBoundingBox(STR_COMPANY_VIEW_RELOCATE_HQ).width);
 				size->width = std::max(size->width, GetStringBoundingBox(STR_COMPANY_VIEW_INFRASTRUCTURE_BUTTON).width);
 				size->width = std::max(size->width, GetStringBoundingBox(STR_COMPANY_VIEW_GIVE_MONEY_BUTTON).width);
+				size->width = std::max(size->width, GetStringBoundingBox(STR_COMPANY_VIEW_HOSTILE_TAKEOVER_BUTTON).width);
 				size->width = std::max(size->width, GetStringBoundingBox(STR_COMPANY_VIEW_PASSWORD).width);
 				size->width = std::max(size->width, GetStringBoundingBox(STR_COMPANY_VIEW_JOIN).width);
 				size->width += padding.width;
@@ -2600,6 +2615,10 @@ struct CompanyWindow : Window
 				ShowQueryString(STR_EMPTY, STR_COMPANY_VIEW_GIVE_MONEY_QUERY_CAPTION, 30, this, CS_NUMERAL, QSF_NONE);
 				break;
 
+			case WID_C_HOSTILE_TAKEOVER:
+				ShowBuyCompanyDialog((CompanyID)this->window_number, true);
+				break;
+
 			case WID_C_COMPANY_PASSWORD:
 				if (this->window_number == _local_company) ShowNetworkCompanyPasswordWindow(this);
 				break;
@@ -2697,9 +2716,12 @@ void DirtyCompanyInfrastructureWindows(CompanyID company)
 }
 
 struct BuyCompanyWindow : Window {
-	BuyCompanyWindow(WindowDesc *desc, WindowNumber window_number) : Window(desc)
+	BuyCompanyWindow(WindowDesc *desc, WindowNumber window_number, bool hostile_takeover) : Window(desc), hostile_takeover(hostile_takeover)
 	{
 		this->InitNested(window_number);
+
+		const Company *c = Company::Get((CompanyID)this->window_number);
+		this->company_value = hostile_takeover ? CalculateHostileTakeoverValue(c) : c->bankrupt_value;
 	}
 
 	void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize) override
@@ -2712,8 +2734,8 @@ struct BuyCompanyWindow : Window {
 			case WID_BC_QUESTION:
 				const Company *c = Company::Get((CompanyID)this->window_number);
 				SetDParam(0, c->index);
-				SetDParam(1, c->bankrupt_value);
+				SetDParam(1, this->company_value);
-				size->height = GetStringHeight(STR_BUY_COMPANY_MESSAGE, size->width);
+				size->height = GetStringHeight(this->hostile_takeover ? STR_BUY_COMPANY_HOSTILE_TAKEOVER : STR_BUY_COMPANY_MESSAGE, size->width);
 				break;
 		}
 	}
@@ -2740,8 +2762,8 @@ struct BuyCompanyWindow : Window {
 			case WID_BC_QUESTION: {
 				const Company *c = Company::Get((CompanyID)this->window_number);
 				SetDParam(0, c->index);
-				SetDParam(1, c->bankrupt_value);
+				SetDParam(1, this->company_value);
-				DrawStringMultiLine(r.left, r.right, r.top, r.bottom, STR_BUY_COMPANY_MESSAGE, TC_FROMSTRING, SA_CENTER);
+				DrawStringMultiLine(r.left, r.right, r.top, r.bottom, this->hostile_takeover ? STR_BUY_COMPANY_HOSTILE_TAKEOVER : STR_BUY_COMPANY_MESSAGE, TC_FROMSTRING, SA_CENTER);
 				break;
 			}
 		}
@@ -2755,10 +2777,29 @@ struct BuyCompanyWindow : Window {
 				break;
 
 			case WID_BC_YES:
-				Command<CMD_BUY_COMPANY>::Post(STR_ERROR_CAN_T_BUY_COMPANY, (CompanyID)this->window_number);
+				Command<CMD_BUY_COMPANY>::Post(STR_ERROR_CAN_T_BUY_COMPANY, (CompanyID)this->window_number, this->hostile_takeover);
 				break;
 		}
 	}
+
+	/**
+	 * Check on a regular interval if the company value has changed.
+	 */
+	IntervalTimer<TimerWindow> rescale_interval = {std::chrono::seconds(3), [this](auto) {
+		/* Value can't change when in bankruptcy. */
+		if (!this->hostile_takeover) return;
+
+		const Company *c = Company::Get((CompanyID)this->window_number);
+		auto new_value = CalculateHostileTakeoverValue(c);
+		if (new_value != this->company_value) {
+			this->company_value = new_value;
+			this->ReInit();
+		}
+	}};
+
+private:
+	bool hostile_takeover; ///< Whether the window is showing a hostile takeover.
+	Money company_value; ///< The value of the company for which the user can buy it.
 };
 
 static const NWidgetPart _nested_buy_company_widgets[] = {
@@ -2790,8 +2831,12 @@ static WindowDesc _buy_company_desc(
 /**
  * Show the query to buy another company.
  * @param company The company to buy.
+ * @param hostile_takeover Whether this is a hostile takeover.
  */
-void ShowBuyCompanyDialog(CompanyID company)
+void ShowBuyCompanyDialog(CompanyID company, bool hostile_takeover)
 {
-	AllocateWindowDescFront<BuyCompanyWindow>(&_buy_company_desc, company);
+	auto window = BringWindowToFrontById(WC_BUY_COMPANY, company);
+	if (window == nullptr) {
+		new BuyCompanyWindow(&_buy_company_desc, company, hostile_takeover);
+	}
 }

src/economy.cpp

@@ -105,15 +105,12 @@ Prices _price;
 static PriceMultipliers _price_base_multiplier;
 
 /**
- * Calculate the value of the company. That is the value of all
+ * Calculate the value of the assets of a company.
- * assets (vehicles, stations) and money minus the loan,
+ *
- * except when including_loan is \c false which is useful when
+ * @param c The company to calculate the value of.
- * we want to calculate the value for bankruptcy.
+ * @return The value of the assets of the company.
- * @param c the company to get the value of.
- * @param including_loan include the loan in the company value.
- * @return the value of the company.
  */
-Money CalculateCompanyValue(const Company *c, bool including_loan)
+static Money CalculateCompanyAssetValue(const Company *c)
 {
 	Owner owner = c->index;
 
@@ -136,6 +133,22 @@ Money CalculateCompanyValue(const Company *c, bool including_loan)
 		}
 	}
 
+	return value;
+}
+
+/**
+ * Calculate the value of the company. That is the value of all
+ * assets (vehicles, stations) and money (including loan),
+ * except when including_loan is \c false which is useful when
+ * we want to calculate the value for bankruptcy.
+ * @param c the company to get the value of.
+ * @param including_loan include the loan in the company value.
+ * @return the value of the company.
+ */
+Money CalculateCompanyValue(const Company *c, bool including_loan)
+{
+	Money value = CalculateCompanyAssetValue(c);
+
 	/* Add real money value */
 	if (including_loan) value -= c->current_loan;
 	value += c->money;
@@ -143,6 +156,39 @@ Money CalculateCompanyValue(const Company *c, bool including_loan)
 	return std::max<Money>(value, 1);
 }
 
+/**
+ * Calculate what you have to pay to take over a company.
+ *
+ * This is different from bankruptcy and company value, and involves a few
+ * more parameters to make it more realistic.
+ *
+ * You have to pay for:
+ * - The value of all the assets in the company.
+ * - The loan the company has (the investors really want their money back).
+ * - The profit for the next two years (if positive) based on the last four quarters.
+ *
+ * And on top of that, they walk away with all the money they have in the bank.
+ *
+ * @param c the company to get the value of.
+ * @return The value of the company.
+ */
+Money CalculateHostileTakeoverValue(const Company *c)
+{
+	Money value = CalculateCompanyAssetValue(c);
+
+	value += c->current_loan;
+	/* Negative balance is basically a loan. */
+	if (c->money < 0) {
+		value += -c->money;
+	}
+
+	for (int quarter = 0; quarter < 4; quarter++) {
+		value += std::max<Money>(c->old_economy[quarter].income - c->old_economy[quarter].expenses, 0) * 2;
+	}
+
+	return std::max<Money>(value, 1);
+}
+
 /**
  * if update is set to true, the economy is updated with this score
  *  (also the house is updated, should only be true in the on-tick event)
@@ -1940,14 +1986,14 @@ static IntervalTimer<TimerGameCalendar> _companies_monthly({TimerGameCalendar::M
 	HandleEconomyFluctuations();
 });
 
-static void DoAcquireCompany(Company *c)
+static void DoAcquireCompany(Company *c, bool hostile_takeover)
 {
 	CompanyID ci = c->index;
 
 	CompanyNewsInformation *cni = new CompanyNewsInformation(c, Company::Get(_current_company));
 
 	SetDParam(0, STR_NEWS_COMPANY_MERGER_TITLE);
-	SetDParam(1, c->bankrupt_value == 0 ? STR_NEWS_MERGER_TAKEOVER_TITLE : STR_NEWS_COMPANY_MERGER_DESCRIPTION);
+	SetDParam(1, hostile_takeover ? STR_NEWS_MERGER_TAKEOVER_TITLE : STR_NEWS_COMPANY_MERGER_DESCRIPTION);
 	SetDParamStr(2, cni->company_name);
 	SetDParamStr(3, cni->other_company_name);
 	SetDParam(4, c->bankrupt_value);
@@ -1957,14 +2003,6 @@ static void DoAcquireCompany(Company *c)
 
 	ChangeOwnershipOfCompanyItems(ci, _current_company);
 
-	if (c->bankrupt_value == 0) {
-		Company *owner = Company::Get(_current_company);
-
-		/* Get both the balance and the loan of the company you just bought. */
-		SubtractMoneyFromCompany(CommandCost(EXPENSES_OTHER, -c->money));
-		owner->current_loan += c->current_loan;
-	}
-
 	if (c->is_ai) AI::Stop(c->index);
 
 	CloseCompanyWindows(ci);
@@ -1983,15 +2021,23 @@ static void DoAcquireCompany(Company *c)
  * @todo currently this only works for AI companies
  * @param flags type of operation
  * @param target_company company to buy up
+ * @param hostile_takeover whether to buy up the company even if it is not bankrupt
  * @return the cost of this operation or an error
  */
-CommandCost CmdBuyCompany(DoCommandFlag flags, CompanyID target_company)
+CommandCost CmdBuyCompany(DoCommandFlag flags, CompanyID target_company, bool hostile_takeover)
 {
 	Company *c = Company::GetIfValid(target_company);
 	if (c == nullptr) return CMD_ERROR;
 
+	/* If you do a hostile takeover but the company went bankrupt, buy it via bankruptcy rules. */
+	if (hostile_takeover && HasBit(c->bankrupt_asked, _current_company)) hostile_takeover = false;
+
 	/* Disable takeovers when not asked */
-	if (!HasBit(c->bankrupt_asked, _current_company)) return CMD_ERROR;
+	if (!hostile_takeover && !HasBit(c->bankrupt_asked, _current_company)) return CMD_ERROR;
+
+	/* Only allow hostile takeover of AI companies and when in single player */
+	if (hostile_takeover && !c->is_ai) return CMD_ERROR;
+	if (hostile_takeover && _networking) return CMD_ERROR;
 
 	/* Disable taking over the local company in singleplayer mode */
 	if (!_networking && _local_company == c->index) return CMD_ERROR;
@@ -2002,11 +2048,13 @@ CommandCost CmdBuyCompany(DoCommandFlag flags, CompanyID target_company)
 	/* Disable taking over when not allowed. */
 	if (!MayCompanyTakeOver(_current_company, target_company)) return CMD_ERROR;
 
-	/* Get the cost here as the company is deleted in DoAcquireCompany. */
+	/* Get the cost here as the company is deleted in DoAcquireCompany.
-	CommandCost cost(EXPENSES_OTHER, c->bankrupt_value);
+	 * For bankruptcy this amount is calculated when the offer was made;
+	 * for hostile takeover you pay the current price. */
+	CommandCost cost(EXPENSES_OTHER, hostile_takeover ? CalculateHostileTakeoverValue(c) : c->bankrupt_value);
 
 	if (flags & DC_EXEC) {
-		DoAcquireCompany(c);
+		DoAcquireCompany(c, hostile_takeover);
 	}
 	return cost;
 }

src/economy_cmd.h

@@ -13,7 +13,7 @@
 #include "command_type.h"
 #include "company_type.h"
 
-CommandCost CmdBuyCompany(DoCommandFlag flags, CompanyID target_company);
+CommandCost CmdBuyCompany(DoCommandFlag flags, CompanyID target_company, bool hostile_takeover);
 
 DEF_CMD_TRAIT(CMD_BUY_COMPANY,           CmdBuyCompany,         0, CMDT_MONEY_MANAGEMENT)
 

src/lang/english.txt

@@ -846,7 +846,7 @@ STR_NEWS_COMPANY_BANKRUPT_TITLE                                 :{BIG_FONT}{BLAC
 STR_NEWS_COMPANY_BANKRUPT_DESCRIPTION                           :{BIG_FONT}{BLACK}{RAW_STRING} has been closed down by creditors and all assets sold off!
 STR_NEWS_COMPANY_LAUNCH_TITLE                                   :{BIG_FONT}{BLACK}New transport company launched!
 STR_NEWS_COMPANY_LAUNCH_DESCRIPTION                             :{BIG_FONT}{BLACK}{RAW_STRING} starts construction near {TOWN}!
-STR_NEWS_MERGER_TAKEOVER_TITLE                                  :{BIG_FONT}{BLACK}{RAW_STRING} has been taken over by {RAW_STRING}!
+STR_NEWS_MERGER_TAKEOVER_TITLE                                  :{BIG_FONT}{BLACK}{RAW_STRING} has been taken over by {RAW_STRING} for an undisclosed amount!
 STR_PRESIDENT_NAME_MANAGER                                      :{BLACK}{PRESIDENT_NAME}{}(Manager)
 
 STR_NEWS_NEW_TOWN                                               :{BLACK}{BIG_FONT}{RAW_STRING} sponsored construction of new town {TOWN}!
@@ -3760,6 +3760,8 @@ STR_COMPANY_VIEW_INFRASTRUCTURE_BUTTON                          :{BLACK}Details
 STR_COMPANY_VIEW_INFRASTRUCTURE_TOOLTIP                         :{BLACK}View detailed infrastructure counts
 STR_COMPANY_VIEW_GIVE_MONEY_BUTTON                              :{BLACK}Give money
 STR_COMPANY_VIEW_GIVE_MONEY_TOOLTIP                             :{BLACK}Give money to this company
+STR_COMPANY_VIEW_HOSTILE_TAKEOVER_BUTTON                        :{BLACK}Hostile takeover
+STR_COMPANY_VIEW_HOSTILE_TAKEOVER_TOOLTIP                       :{BLACK}Do a hostile takeover of this company
 
 STR_COMPANY_VIEW_NEW_FACE_BUTTON                                :{BLACK}New Face
 STR_COMPANY_VIEW_NEW_FACE_TOOLTIP                               :{BLACK}Select new face for manager
@@ -3775,6 +3777,7 @@ STR_COMPANY_VIEW_PRESIDENT_S_NAME_QUERY_CAPTION                 :Manager's Name
 STR_COMPANY_VIEW_GIVE_MONEY_QUERY_CAPTION                       :Enter the amount of money you want to give
 
 STR_BUY_COMPANY_MESSAGE                                         :{WHITE}We are looking for a transport company to take-over our company.{}{}Do you want to purchase {COMPANY} for {CURRENCY_LONG}?
+STR_BUY_COMPANY_HOSTILE_TAKEOVER                                :{WHITE}In a hostile takeover of {COMPANY} you will purchase all assets, pay off all loans, and pay two years worth of profits.{}{}The total is estimated to be {CURRENCY_LONG}.{}{}Do you want to continue this hostile takeover?
 
 # Company infrastructure window
 STR_COMPANY_INFRASTRUCTURE_VIEW_CAPTION                         :{WHITE}Infrastructure of {COMPANY}

src/script/api/script_event_types.cpp

@@ -119,7 +119,7 @@ bool ScriptEventEnginePreview::AcceptPreview()
 bool ScriptEventCompanyAskMerger::AcceptMerger()
 {
 	EnforceCompanyModeValid(false);
-	return ScriptObject::Command<CMD_BUY_COMPANY>::Do((::CompanyID)this->owner);
+	return ScriptObject::Command<CMD_BUY_COMPANY>::Do((::CompanyID)this->owner, false);
 }
 
 ScriptEventAdminPort::ScriptEventAdminPort(const std::string &json) :

src/widgets/company_widget.h

@@ -44,6 +44,9 @@ enum CompanyWidgets {
 	WID_C_SELECT_GIVE_MONEY,          ///< Selection widget for the give money button.
 	WID_C_GIVE_MONEY,                 ///< Button to give money.
 
+	WID_C_SELECT_HOSTILE_TAKEOVER,    ///< Selection widget for the hostile takeover button.
+	WID_C_HOSTILE_TAKEOVER,           ///< Button to hostile takeover another company.
+
 	WID_C_HAS_PASSWORD,               ///< Has company password lock.
 	WID_C_SELECT_MULTIPLAYER,         ///< Multiplayer selection panel.
 	WID_C_COMPANY_PASSWORD,           ///< Button to set company password.