Handling of subsidies. More...

#include "stdafx.h"
#include "company_func.h"
#include "industry.h"
#include "town.h"
#include "news_func.h"
#include "ai/ai.hpp"
#include "station_base.h"
#include "strings_func.h"
#include "window_func.h"
#include "subsidy_base.h"
#include "subsidy_func.h"
#include "core/pool_func.hpp"
#include "core/random_func.hpp"
#include "core/container_func.hpp"
#include "game/game.hpp"
#include "command_func.h"
#include "string_func.h"
#include "tile_cmd.h"
#include "subsidy_cmd.h"
#include "timer/timer.h"
#include "timer/timer_game_economy.h"
#include "table/strings.h"
#include "safeguards.h"

Functions
static void	SetPartOfSubsidyFlag (Source source, PartOfSubsidy flag)
	Sets a flag indicating that given town/industry is part of subsidised route.

void	RebuildSubsidisedSourceAndDestinationCache ()
	Perform a full rebuild of the subsidies cache.

void	DeleteSubsidyWith (Source source)
	Delete the subsidies associated with a given cargo source type and id.

static bool	CheckSubsidyDuplicate (CargoType cargo, Source src, Source dst)
	Check whether a specific subsidy already exists.

static bool	CheckSubsidyDistance (Source src, Source dst)
	Checks if the source and destination of a subsidy are inside the distance limit.

void	CreateSubsidy (CargoType cargo_type, Source src, Source dst)
	Creates a subsidy with the given parameters.

CommandCost	CmdCreateSubsidy (DoCommandFlags flags, CargoType cargo_type, Source src, Source dst)
	Create a new subsidy.

bool	FindSubsidyPassengerRoute ()
	Tries to create a passenger subsidy between two towns.

bool	FindSubsidyCargoDestination (CargoType cargo_type, Source src)
	Tries to find a suitable destination for the given source and cargo.

bool	FindSubsidyTownCargoRoute ()
	Tries to create a cargo subsidy with a town as source.

bool	FindSubsidyIndustryCargoRoute ()
	Tries to create a cargo subsidy with an industry as source.

bool	CheckSubsidised (CargoType cargo_type, CompanyID company, Source src, const Station *st)
	Tests whether given delivery is subsidised and possibly awards the subsidy to delivering company.

Variables
SubsidyPool	_subsidy_pool ("Subsidy")
	Pool for the subsidies.

static const IntervalTimer< TimerGameEconomy >	_economy_subsidies_monthly ({TimerGameEconomy::MONTH, TimerGameEconomy::Priority::SUBSIDY}, [](auto) { bool modified=false;for(Subsidy s :Subsidy::Iterate()) { if(--s->remaining==0) { if(!s->IsAwarded()) { const CargoSpec cs=CargoSpec::Get(s->cargo_type);EncodedString headline=GetEncodedString(STR_NEWS_OFFER_OF_SUBSIDY_EXPIRED, cs->name, s->src.GetFormat(), s->src.id, s->dst.GetFormat(), s->dst.id);AddNewsItem(std::move(headline), NewsType::Subsidies, NewsStyle::Normal, {}, s->src.GetNewsReference(), s->dst.GetNewsReference());AI::BroadcastNewEvent(new ScriptEventSubsidyOfferExpired(s->index));Game::NewEvent(new ScriptEventSubsidyOfferExpired(s->index));} else { if(s->awarded==_local_company) { const CargoSpec *cs=CargoSpec::Get(s->cargo_type);EncodedString headline=GetEncodedString(STR_NEWS_SUBSIDY_WITHDRAWN_SERVICE, cs->name, s->src.GetFormat(), s->src.id, s->dst.GetFormat(), s->dst.id);AddNewsItem(std::move(headline), NewsType::Subsidies, NewsStyle::Normal, {}, s->src.GetNewsReference(), s->dst.GetNewsReference());} AI::BroadcastNewEvent(new ScriptEventSubsidyExpired(s->index));Game::NewEvent(new ScriptEventSubsidyExpired(s->index));} delete s;modified=true;} } if(modified) { RebuildSubsidisedSourceAndDestinationCache();} else if(_settings_game.difficulty.subsidy_duration==0) { return;} else if(_settings_game.linkgraph.distribution_pax !=DT_MANUAL &&_settings_game.linkgraph.distribution_mail !=DT_MANUAL &&_settings_game.linkgraph.distribution_armoured !=DT_MANUAL &&_settings_game.linkgraph.distribution_default !=DT_MANUAL) { return;} bool passenger_subsidy=false;bool town_subsidy=false;bool industry_subsidy=false;int random_chance=RandomRange(16);if(random_chance< 2 &&_settings_game.linkgraph.distribution_pax==DT_MANUAL) { int n=1000;do { passenger_subsidy=FindSubsidyPassengerRoute();} while(!passenger_subsidy &&n--);} else if(random_chance==2) { int n=1000;do { town_subsidy=FindSubsidyTownCargoRoute();} while(!town_subsidy &&n--);} else if(random_chance==3) { int n=1000;do { industry_subsidy=FindSubsidyIndustryCargoRoute();} while(!industry_subsidy &&n--);} modified\|=passenger_subsidy\|\|town_subsidy\|\|industry_subsidy;if(modified) InvalidateWindowData(WC_SUBSIDIES_LIST, 0);})
	Perform the economy monthly update of open subsidies, and try to create a new one.