Load map descriptions from their XML file.

Add basic hold-fire stance, and use it for some test maps.
Add JSON data container to map XML files, to simplify the interaction
between scripts and maps.
Fix fixed-point printing so it roundtrips safely through map files.
Fix camera startup positions in old-format maps.

This was SVN commit r7844.

source/scriptinterface/ScriptInterface.cpp

@@ -22,6 +22,7 @@
 #include "AutoRooters.h"
 
 #include "lib/debug.h"
+#include "lib/utf8.h"
 #include "ps/CLogger.h"
 #include "ps/Profile.h"
 #include "ps/utf16string.h"
@@ -628,6 +629,58 @@ std::wstring ScriptInterface::ToString(jsval obj)
 	return source;
 }
 
+CScriptValRooted ScriptInterface::ParseJSON(const utf16string& string)
+{
+	jsval vp;
+	JSONParser* parser = JS_BeginJSONParse(m->m_cx, &vp);
+	if (!parser)
+	{
+		LOGERROR(L"ParseJSON failed to begin");
+		return CScriptValRooted();
+	}
+
+	if (!JS_ConsumeJSONText(m->m_cx, parser, string.c_str(), string.size()))
+	{
+		LOGERROR(L"ParseJSON failed to consume");
+		return CScriptValRooted();
+	}
+
+	if (!JS_FinishJSONParse(m->m_cx, parser, JSVAL_NULL))
+	{
+		LOGERROR(L"ParseJSON failed to finish");
+		return CScriptValRooted();
+	}
+
+	return CScriptValRooted(m->m_cx, vp);
+}
+
+struct Stringifier
+{
+	static JSBool callback(const jschar *buf, uint32 len, void *data)
+	{
+		utf16string str(buf, buf+len);
+		std::wstring strw(str.begin(), str.end());
+
+		LibError err; // ignore Unicode errors
+		static_cast<Stringifier*>(data)->stream << utf8_from_wstring(strw, &err);
+		return JS_TRUE;
+	}
+
+	std::stringstream stream;
+};
+
+std::string ScriptInterface::StringifyJSON(jsval obj)
+{
+	Stringifier str;
+	if (!JS_Stringify(m->m_cx, &obj, NULL, INT_TO_JSVAL(2), &Stringifier::callback, &str))
+	{
+		LOGERROR(L"StringifyJSON failed");
+		return "";
+	}
+
+	return str.stream.str();
+}
+
 void ScriptInterface::ReportError(const char* msg)
 {
 	// JS_ReportError by itself doesn't seem to set a JS-style exception, and so

source/scriptinterface/ScriptInterface.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2010 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -29,6 +29,8 @@
 #include "ScriptTypes.h"
 #include "ScriptVal.h"
 
+#include "ps/utf16string.h"
+
 class AutoGCRooter;
 
 namespace boost { class rand48; }
@@ -154,6 +156,16 @@ public:
 
 	std::wstring ToString(jsval obj);
 
+	/**
+	 * Parse a JSON string. Returns the undefined value on error.
+	 */
+	CScriptValRooted ParseJSON(const utf16string& string);
+
+	/**
+	 * Stringify to a JSON string, UTF-8 encoded. Returns an empty string on error.
+	 */
+	std::string StringifyJSON(jsval obj);
+
 	/**
 	 * Report the given error message through the JS error reporting mechanism,
 	 * and throw a JS exception. (Callers can check IsPendingException, and must

source/scriptinterface/tests/test_ScriptInterface.h

@@ -19,6 +19,7 @@
 
 #include "scriptinterface/ScriptInterface.h"
 
+#include "lib/utf8.h"
 #include "ps/CLogger.h"
 
 #include <boost/random/linear_congruential.hpp>
@@ -125,4 +126,20 @@ public:
 		TS_ASSERT(script.Eval("Math.random()", d2));
 		TS_ASSERT_EQUALS(d1, d2);
 	}
+
+	void test_json()
+	{
+		ScriptInterface script("Test");
+
+		std::string input = "({'x':1,'z':[2,'3\\u263A\\ud800'],\"y\":true})";
+		CScriptValRooted val;
+		TS_ASSERT(script.Eval(input.c_str(), val));
+
+		std::string stringified = script.StringifyJSON(val.get());
+		TS_ASSERT_STR_EQUALS(stringified, "{\n  \"x\":1,\n  \"z\":[2,\n    \"3\xE2\x98\xBA\xEF\xBF\xBD\"\n  ],\n  \"y\":true\n}");
+
+		std::wstring stringifiedw = wstring_from_utf8(stringified.c_str());
+		val = script.ParseJSON(utf16string(stringifiedw.begin(), stringifiedw.end()));
+		TS_ASSERT_WSTR_EQUALS(script.ToString(val.get()), L"({x:1, z:[2, \"3\\u263A\\uFFFD\"], y:true})");
+	}
 };