--- a/projects/openttd.vcproj	Sun Mar 18 16:02:41 2007 +0000
+++ b/projects/openttd.vcproj	Sun Mar 18 18:02:27 2007 +0000
@@ -1009,6 +1009,9 @@
 			Name="AI API"
 			Filter="">
 			<File
+				RelativePath=".\..\src\ai\api\ai_accounting.hpp">
+			</File>
+			<File
 				RelativePath=".\..\src\ai\api\ai_base.hpp">
 			</File>
 			<File
@@ -1046,6 +1049,9 @@
 			Name="AI API Implementation"
 			Filter="">
 			<File
+				RelativePath=".\..\src\ai\api\ai_accounting.cpp">
+			</File>
+			<File
 				RelativePath=".\..\src\ai\api\ai_base.cpp">
 			</File>
 			<File

--- a/projects/openttd_vs80.vcproj	Sun Mar 18 16:02:41 2007 +0000
+++ b/projects/openttd_vs80.vcproj	Sun Mar 18 18:02:27 2007 +0000
@@ -1564,6 +1564,10 @@
 			Name="AI API"
 			>
 			<File
+				RelativePath=".\..\src\ai\api\ai_accounting.hpp"
+				>
+			</File>
+			<File
 				RelativePath=".\..\src\ai\api\ai_base.hpp"
 				>
 			</File>
@@ -1612,6 +1616,10 @@
 			Name="AI API Implementation"
 			>
 			<File
+				RelativePath=".\..\src\ai\api\ai_accounting.cpp"
+				>
+			</File>
+			<File
 				RelativePath=".\..\src\ai\api\ai_base.cpp"
 				>
 			</File>

--- a/source.list	Sun Mar 18 16:02:41 2007 +0000
+++ b/source.list	Sun Mar 18 18:02:27 2007 +0000
@@ -308,6 +308,7 @@
 ai/NoAI/NoAI.hpp
 
 # AI API
+ai/api/ai_accounting.hpp
 ai/api/ai_base.hpp
 ai/api/ai_cargo.hpp
 ai/api/ai_company.hpp
@@ -321,6 +322,7 @@
 ai/api/ai_testmode.hpp
 
 # AI API Implementation
+ai/api/ai_accounting.cpp
 ai/api/ai_base.cpp
 ai/api/ai_cargo.cpp
 ai/api/ai_company.cpp

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ai/api/ai_accounting.cpp	Sun Mar 18 18:02:27 2007 +0000
@@ -0,0 +1,26 @@
+/* $Id$ */
+
+/** @file ai_accounting.cpp everything to handle AI accounting things */
+
+#include "ai_accounting.hpp"
+
+int32 AIAccounting::GetCosts()
+{
+	return this->GetDoCommandCosts();
+}
+
+void AIAccounting::ResetCosts()
+{
+	this->SetDoCommandCosts(0);
+}
+
+AIAccounting::AIAccounting()
+{
+	this->last_costs = this->GetDoCommandCosts();
+	this->SetDoCommandCosts(0);
+}
+
+AIAccounting::~AIAccounting()
+{
+	this->SetDoCommandCosts(this->last_costs);
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ai/api/ai_accounting.hpp	Sun Mar 18 18:02:27 2007 +0000
@@ -0,0 +1,60 @@
+/* $Id$ */
+
+/** @file ai_accounting.hpp everything to handle AI accounting things */
+
+#ifndef AI_ACCOUNTING_HPP
+#define AI_ACCOUNTING_HPP
+
+#include "ai_object.hpp"
+
+/**
+ * Class that handles all AI accounting related functions.
+ * Example:
+ *   {
+ *     local costs = AIAccounting();
+ *     BuildRoad(from_here, to_here);
+ *     BuildRoad(from_there, to_there);
+ *     print("Costs for route is: " + costs.GetCosts());
+ *   }
+ */
+class AIAccounting : public AIObject {
+private:
+	int32 last_costs;
+public:
+	/**
+	 * Creating instance of this class starts counting the costs of commands
+	 *   from zero.
+	 * @note when the instance is destroyed, he restores the costs that was
+	 *   current when the instance was created!
+	 */
+	AIAccounting();
+
+	/**
+	 * Destroying this instance reset the costs to the value it was
+	 *   in when the instance was created.
+	 */
+	~AIAccounting();
+
+	/**
+	 * Get the current value of the costs.
+	 */
+	int32 GetCosts();
+
+	/**
+	 * Reset the costs to zero.
+	 */
+	void ResetCosts();
+};
+
+#ifdef DEFINE_SQUIRREL_CLASS
+void SQAIAccountingRegister(Squirrel *engine) {
+	DefSQClass <AIAccounting> SQAIAccounting("AIAccounting");
+	SQAIAccounting.PreRegister(engine);
+	SQAIAccounting.AddConstructor(engine);
+	SQAIAccounting.DefSQFunction(engine, &AIAccounting::GetCosts, "GetCosts");
+	SQAIAccounting.DefSQFunction(engine, &AIAccounting::ResetCosts, "ResetCosts");
+	SQAIAccounting.PostRegister(engine);
+}
+#endif /* SQUIRREL_CLASS */
+
+#endif /* AI_ACCOUNTING_HPP */

--- a/src/ai/api/ai_company.cpp	Sun Mar 18 16:02:41 2007 +0000
+++ b/src/ai/api/ai_company.cpp	Sun Mar 18 18:02:27 2007 +0000
@@ -62,15 +62,15 @@
 	/* When we get/repay everything at once (or the maximum we can repay),
 	 * use the shortcut for that. Otherwise send several commands at once */
 	if (loan == 0) {
-		return this->CmdSucceeded(this->DoCommand(0, 0, true, DC_EXEC, CMD_DECREASE_LOAN));
+		return this->DoCommand(0, 0, true, DC_EXEC, CMD_DECREASE_LOAN);
 	}
 	if (loan == this->GetMaxLoanAmount()) {
-		return this->CmdSucceeded(this->DoCommand(0, 0, true, DC_EXEC, CMD_INCREASE_LOAN));
+		return this->DoCommand(0, 0, true, DC_EXEC, CMD_INCREASE_LOAN);
 	}
 
 	bool increase = loan > this->GetLoanAmount();
 	for (uint diff_loan = abs(loan - this->GetLoanAmount()) / this->GetLoanInterval(); diff_loan > 0; diff_loan--) {
-		if (this->CmdFailed(this->DoCommand(0, 0, false, DC_EXEC, increase ? CMD_INCREASE_LOAN : CMD_DECREASE_LOAN))) return false;
+		if (!this->DoCommand(0, 0, false, DC_EXEC, increase ? CMD_INCREASE_LOAN : CMD_DECREASE_LOAN)) return false;
 	}
 
 	return true;

--- a/src/ai/api/ai_object.cpp	Sun Mar 18 16:02:41 2007 +0000
+++ b/src/ai/api/ai_object.cpp	Sun Mar 18 18:02:27 2007 +0000
@@ -29,14 +29,19 @@
 	return AIObject::GetDoCommandStruct(_current_player)->mode;
 }
 
-bool AIObject::CmdFailed(int32 res)
+void AIObject::SetDoCommandCosts(int32 value)
 {
-	return ::CmdFailed(res);
+	AIObject::GetDoCommandStruct(_current_player)->costs = value;
 }
 
-bool AIObject::CmdSucceeded(int32 res)
+void AIObject::IncreaseDoCommandCosts(int32 value)
 {
-	return !::CmdFailed(res);
+	AIObject::GetDoCommandStruct(_current_player)->costs += value;
+}
+
+int32 AIObject::GetDoCommandCosts()
+{
+	return AIObject::GetDoCommandStruct(_current_player)->costs;
 }
 
 AIObject::AIDoCommandStruct *AIObject::GetDoCommandStruct(PlayerID player)
@@ -51,13 +56,14 @@
 		for (int i = 0; i < MAX_PLAYERS; i++) {
 			command_struct[i].mode = NULL;
 			command_struct[i].delay = 1;
+			command_struct[i].costs = 0;
 		}
 	}
 
 	return &command_struct[player];
 }
 
-int32 AIObject::DoCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 flags, uint procc)
+bool AIObject::DoCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 flags, uint procc)
 {
 	PlayerID old_lp;
 	int32 res = 0;
@@ -69,10 +75,13 @@
 	/* First, do a test-run to see if we can do this */
 	res = ::DoCommand(tile, p1, p2, flags & ~DC_EXEC, procc);
 	/* The command failed, so return */
-	if (this->CmdFailed(res)) return res;
+	if (::CmdFailed(res)) return false;
 
 	/* Check what the callback wants us to do */
-	if (this->GetDoCommandMode() != NULL && !this->GetDoCommandMode()(tile, p1, p2, flags, procc)) return res;
+	if (this->GetDoCommandMode() != NULL && !this->GetDoCommandMode()(tile, p1, p2, flags, procc)) {
+		this->IncreaseDoCommandCosts(res);
+		return true;
+	}
 
 	/* Restore _cmd_text */
 	_cmd_text = tmp_cmdtext;
@@ -106,5 +115,8 @@
 		AI_SuspendPlayer(_current_player, this->GetDoCommandDelay());
 	}
 
-	return res;
+	if (::CmdFailed(res)) return false;
+
+	this->IncreaseDoCommandCosts(res);
+	return true;
 }

--- a/src/ai/api/ai_object.hpp	Sun Mar 18 16:02:41 2007 +0000
+++ b/src/ai/api/ai_object.hpp	Sun Mar 18 18:02:27 2007 +0000
@@ -21,6 +21,7 @@
 	struct AIDoCommandStruct {
 		AIModeProc *mode;
 		uint delay;
+		int32 costs;
 	};
 
 	/**
@@ -32,17 +33,22 @@
 	/**
 	 * Executes a raw DoCommand for the AI.
 	 */
-	int32 DoCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 flags, uint procc);
+	bool DoCommand(TileIndex tile, uint32 p1, uint32 p2, uint32 flags, uint procc);
 
 	/**
-	 * Checks if the result of a DoCommand went wrong.
+	 * Sets the DoCommand costs counter to a value.
 	 */
-	bool CmdFailed(int32 res);
+	void SetDoCommandCosts(int32 value);
 
 	/**
-	 * Checks if the result of a DoCommand went okay.
+	 * Increase the current value of the DoCommand costs counter.
 	 */
-	bool CmdSucceeded(int32 res);
+	void IncreaseDoCommandCosts(int32 value);
+
+	/**
+	 * Get the current DoCommand costs counter.
+	 */
+	int32 GetDoCommandCosts();
 
 	/**
 	 * Set the current mode of your AI to this proc.

--- a/src/ai/api/ai_settings.hpp	Sun Mar 18 16:02:41 2007 +0000
+++ b/src/ai/api/ai_settings.hpp	Sun Mar 18 18:02:27 2007 +0000
@@ -9,7 +9,6 @@
 
 /**
  * Class that handles all AI settings related functions.
- * @note This isn't available from your AI.
  */
 class AISettings : public AIObject {
 public: