refactor(internal): Turn variant into its own class (#6592)

thomasballinger · May 13, 2022 · 4dc603e · 4dc603e
1 parent 8bd80d3
commit 4dc603e
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Showing 6 changed files with 196 additions and 101 deletions.
diff --git a/EndlessSky.xcodeproj/project.pbxproj b/EndlessSky.xcodeproj/project.pbxproj
@@ -27,6 +27,7 @@
 		87D6407E8B579EB502BFBCE5 /* GameAction.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 9F0F4096A9008E2D8F3304BB /* GameAction.cpp */; };
 		88A64339B56EBA1F7923E1C7 /* GameLoadingPanel.cpp in Sources */ = {isa = PBXBuildFile; fileRef = A7E640C7A366679B27CCADAC /* GameLoadingPanel.cpp */; };
 		90CF46CE84794C6186FC6CE2 /* EsUuid.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 950742538F8CECF5D4168FBC /* EsUuid.cpp */; };
+		920F40E0ADECA8926F423FDA /* Variant.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 61FA4C2BB89E08C5E2B8B4B9 /* Variant.cpp */; };
 		94DF4B5B8619F6A3715D6168 /* Weather.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8E8A4C648B242742B22A34FA /* Weather.cpp */; };
 		9E1F4BF78F9E1FC4C96F76B5 /* Test.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 2E8047A8987DD8EC99FF8E2E /* Test.cpp */; };
 		A90633FF1EE602FD000DA6C0 /* LogbookPanel.cpp in Sources */ = {isa = PBXBuildFile; fileRef = A90633FD1EE602FD000DA6C0 /* LogbookPanel.cpp */; };
@@ -227,6 +228,8 @@
 		5155CD721DBB9FF900EF090B /* Depreciation.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = Depreciation.h; path = source/Depreciation.h; sourceTree = "<group>"; };
 		5CE3475B85CE8C48D98664B7 /* Test.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = Test.h; path = source/Test.h; sourceTree = "<group>"; };
 		5CF247B48EEC7A3C366C1DFA /* DamageDealt.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = DamageDealt.h; path = source/DamageDealt.h; sourceTree = "<group>"; };
+		5EBC44769E84CF0C953D08B3 /* Variant.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = Variant.h; path = source/Variant.h; sourceTree = "<group>"; };
+		61FA4C2BB89E08C5E2B8B4B9 /* Variant.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Variant.cpp; path = source/Variant.cpp; sourceTree = "<group>"; };
 		6245F8231D301C7400A7A094 /* Body.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Body.cpp; path = source/Body.cpp; sourceTree = "<group>"; };
 		6245F8241D301C7400A7A094 /* Body.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = Body.h; path = source/Body.h; sourceTree = "<group>"; };
 		6245F8261D301C9000A7A094 /* Hardpoint.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = Hardpoint.cpp; path = source/Hardpoint.cpp; sourceTree = "<group>"; };
@@ -858,6 +861,8 @@
 				5CF247B48EEC7A3C366C1DFA /* DamageDealt.h */,
 				D0FA4800BE72C1B5A7D567B9 /* MenuAnimationPanel.cpp */,
 				8CB543A1AA20F764DD7FC15A /* MenuAnimationPanel.h */,
+				61FA4C2BB89E08C5E2B8B4B9 /* Variant.cpp */,
+				5EBC44769E84CF0C953D08B3 /* Variant.h */,
 			);
 			name = source;
 			sourceTree = "<group>";
@@ -1215,6 +1220,7 @@
 				027A4E858B292CE9F0A06F89 /* FireCommand.cpp in Sources */,
 				E3D54794A1EEF51CD4859170 /* DamageProfile.cpp in Sources */,
 				F35E4D6EA465D71CDA282EBA /* MenuAnimationPanel.cpp in Sources */,
+				920F40E0ADECA8926F423FDA /* Variant.cpp in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

diff --git a/EndlessSkyLib.cbp b/EndlessSkyLib.cbp
@@ -335,6 +335,8 @@
 		<Unit filename="source/UI.h" />
 		<Unit filename="source/UniverseObjects.cpp" />
 		<Unit filename="source/UniverseObjects.h" />
+		<Unit filename="source/Variant.cpp" />
+		<Unit filename="source/Variant.h" />
 		<Unit filename="source/Visual.cpp" />
 		<Unit filename="source/Visual.h" />
 		<Unit filename="source/Weapon.cpp" />

diff --git a/source/Fleet.cpp b/source/Fleet.cpp
@@ -26,6 +26,7 @@ PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 
 #include <algorithm>
 #include <cmath>
+#include <functional>
 #include <iterator>
 
 using namespace std;
@@ -204,27 +205,17 @@ void Fleet::Load(const DataNode &node)
 			{
 				resetVariants = false;
 				variants.clear();
-				total = 0;
 			}
 			variants.emplace_back(child);
-			total += variants.back().weight;
 		}
 		else if(key == "variant")
 		{
-			// If given a full ship definition of one of this fleet's variant members, remove the variant.
-			bool didRemove = false;
+			// If given a full definition of one of this fleet's variant members, remove the variant.
 			Variant toRemove(child);
-			for(auto it = variants.begin(); it != variants.end(); ++it)
-				if(toRemove.ships.size() == it->ships.size() &&
-					is_permutation(it->ships.begin(), it->ships.end(), toRemove.ships.begin()))
-				{
-					total -= it->weight;
-					variants.erase(it);
-					didRemove = true;
-					break;
-				}
-
-			if(!didRemove)
+			auto removeIt = std::remove(variants.begin(), variants.end(), toRemove);
+			if(removeIt != variants.end())
+				variants.erase(removeIt, variants.end());
+			else
 				child.PrintTrace("Warning: Did not find matching variant for specified operation:");
 		}
 		else
@@ -249,11 +240,10 @@ bool Fleet::IsValid(bool requireGovernment) const
 	if(fighterNames && fighterNames->IsEmpty())
 		return false;
 
-	// A fleet's variants should reference at least one valid ship.
-	for(auto &&v : variants)
-		if(none_of(v.ships.begin(), v.ships.end(),
-				[](const Ship *const s) noexcept -> bool { return s->IsValid(); }))
-			return false;
+	// Any variant a fleet could choose should be valid.
+	if(any_of(variants.begin(), variants.end(),
+			[](const Variant &v) noexcept -> bool { return !v.IsValid(); }))
+		return false;
 
 	return true;
 }
@@ -264,28 +254,21 @@ void Fleet::RemoveInvalidVariants()
 {
 	auto IsInvalidVariant = [](const Variant &v) noexcept -> bool
 	{
-		return v.ships.empty() || none_of(v.ships.begin(), v.ships.end(),
-			[](const Ship *const s) noexcept -> bool { return s->IsValid(); });
+		return !v.IsValid();
 	};
 	auto firstInvalid = find_if(variants.begin(), variants.end(), IsInvalidVariant);
 	if(firstInvalid == variants.end())
 		return;
 
 	// Ensure the class invariant can be maintained.
-	// (This must be done first as we cannot do anything but `erase` elements filtered by `remove_if`.)
-	int removedWeight = 0;
-	for(auto it = firstInvalid; it != variants.end(); ++it)
-		if(IsInvalidVariant(*it))
-			removedWeight += it->weight;
-
+	int total = variants.TotalWeight();
 	auto removeIt = remove_if(firstInvalid, variants.end(), IsInvalidVariant);
 	int count = distance(removeIt, variants.end());
+	variants.erase(removeIt, variants.end());
+
 	Files::LogError("Warning: " + (fleetName.empty() ? "unnamed fleet" : "fleet \"" + fleetName + "\"")
 		+ ": Removing " + to_string(count) + " invalid " + (count > 1 ? "variants" : "variant")
-		+ " (" + to_string(removedWeight) + " of " + to_string(total) + " weight)");
-
-	total -= removedWeight;
-	variants.erase(removeIt, variants.end());
+		+ " (" + to_string(total - variants.TotalWeight()) + " of " + to_string(total) + " weight)");
 }
 
 
@@ -300,12 +283,12 @@ const Government *Fleet::GetGovernment() const
 // Choose a fleet to be created during flight, and have it enter the system via jump or planetary departure.
 void Fleet::Enter(const System &system, list<shared_ptr<Ship>> &ships, const Planet *planet) const
 {
-	if(!total || variants.empty() || personality.IsDerelict())
+	if(variants.empty() || personality.IsDerelict())
 		return;
 
 	// Pick a fleet variant to instantiate.
-	const Variant &variant = ChooseVariant();
-	if(variant.ships.empty())
+	const vector<const Ship *> &variantShips = variants.Get().Ships();
+	if(variantShips.empty())
 		return;
 
 	// Figure out what system the fleet is starting in, where it is going, and
@@ -328,7 +311,7 @@ void Fleet::Enter(const System &system, list<shared_ptr<Ship>> &ships, const Pla
 		bool hasJump = false;
 		bool hasHyper = false;
 		double jumpDistance = System::DEFAULT_NEIGHBOR_DISTANCE;
-		for(const Ship *ship : variant.ships)
+		for(const Ship *ship : variantShips)
 		{
 			if(ship->Attributes().Get("jump drive"))
 			{
@@ -393,7 +376,7 @@ void Fleet::Enter(const System &system, list<shared_ptr<Ship>> &ships, const Pla
 			source = linkVector[choice];
 	}
 
-	auto placed = Instantiate(variant);
+	auto placed = Instantiate(variantShips);
 	// Carry all ships that can be carried, as they don't need to be positioned
 	// or checked to see if they can access a particular planet.
 	for(auto &ship : placed)
@@ -469,20 +452,20 @@ void Fleet::Enter(const System &system, list<shared_ptr<Ship>> &ships, const Pla
 // only uncarried ships will be added to the list (as any carriables will be stored in bays).
 void Fleet::Place(const System &system, list<shared_ptr<Ship>> &ships, bool carried) const
 {
-	if(!total || variants.empty())
+	if(variants.empty())
 		return;
 
 	// Pick a fleet variant to instantiate.
-	const Variant &variant = ChooseVariant();
-	if(variant.ships.empty())
+	const vector<const Ship *> &variantShips = variants.Get().Ships();
+	if(variantShips.empty())
 		return;
 
 	// Determine where the fleet is going to or coming from.
 	auto center = ChooseCenter(system);
 
 	// Place all the ships in the chosen fleet variant.
 	shared_ptr<Ship> flagship;
-	vector<shared_ptr<Ship>> placed = Instantiate(variant);
+	vector<shared_ptr<Ship>> placed = Instantiate(variantShips);
 	for(shared_ptr<Ship> &ship : placed)
 	{
 		// If this is a fighter and someone can carry it, no need to position it.
@@ -558,49 +541,7 @@ void Fleet::Place(const System &system, Ship &ship)
 
 int64_t Fleet::Strength() const
 {
-	if(!total || variants.empty())
-		return 0;
-
-	int64_t sum = 0;
-	for(const Variant &variant : variants)
-	{
-		int64_t thisSum = 0;
-		for(const Ship *ship : variant.ships)
-			thisSum += ship->Cost();
-		sum += thisSum * variant.weight;
-	}
-	return sum / total;
-}
-
-
-
-Fleet::Variant::Variant(const DataNode &node)
-{
-	weight = 1;
-	if(node.Token(0) == "variant" && node.Size() >= 2)
-		weight = node.Value(1);
-	else if(node.Token(0) == "add" && node.Size() >= 3)
-		weight = node.Value(2);
-
-	for(const DataNode &child : node)
-	{
-		int n = 1;
-		if(child.Size() >= 2 && child.Value(1) >= 1.)
-			n = child.Value(1);
-		ships.insert(ships.end(), n, GameData::Ships().Get(child.Token(0)));
-	}
-}
-
-
-
-const Fleet::Variant &Fleet::ChooseVariant() const
-{
-	// Pick a random variant based on the weights.
-	unsigned index = 0;
-	for(int choice = Random::Int(total); choice >= variants[index].weight; ++index)
-		choice -= variants[index].weight;
-
-	return variants[index];
+	return variants.Average(std::mem_fn(&Variant::Strength));
 }
 
 
@@ -621,10 +562,10 @@ pair<Point, double> Fleet::ChooseCenter(const System &system)
 
 
 
-vector<shared_ptr<Ship>> Fleet::Instantiate(const Variant &variant) const
+vector<shared_ptr<Ship>> Fleet::Instantiate(const vector<const Ship *> &ships) const
 {
 	vector<shared_ptr<Ship>> placed;
-	for(const Ship *model : variant.ships)
+	for(const Ship *model : ships)
 	{
 		// At least one of this variant's ships is valid, but we should avoid spawning any that are not defined.
 		if(!model->IsValid())

diff --git a/source/Fleet.h b/source/Fleet.h
@@ -15,6 +15,8 @@ PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 
 #include "Personality.h"
 #include "Sale.h"
+#include "Variant.h"
+#include "WeightedList.h"
 
 #include <list>
 #include <memory>
@@ -70,19 +72,8 @@ class Fleet {
 
 
 private:
-	class Variant {
-	public:
-		explicit Variant(const DataNode &node);
-
-		int weight;
-		std::vector<const Ship *> ships;
-	};
-
-
-private:
-	const Variant &ChooseVariant() const;
 	static std::pair<Point, double> ChooseCenter(const System &system);
-	std::vector<std::shared_ptr<Ship>> Instantiate(const Variant &variant) const;
+	std::vector<std::shared_ptr<Ship>> Instantiate(const std::vector<const Ship *> &ships) const;
 	bool PlaceFighter(std::shared_ptr<Ship> fighter, std::vector<std::shared_ptr<Ship>> &placed) const;
 	void SetCargo(Ship *ship) const;
 
@@ -92,9 +83,7 @@ class Fleet {
 	const Government *government = nullptr;
 	const Phrase *names = nullptr;
 	const Phrase *fighterNames = nullptr;
-	std::vector<Variant> variants;
-	// The sum of all available variant weights.
-	int total = 0;
+	WeightedList<Variant> variants;
 	// The number of different items the ships in this fleet will carry in cargo.
 	int cargo = 3;
 	std::vector<std::string> commodities;