added type conversion functions and creation from nullptr

2 files changed, 165 insertions, 19 deletions

diff --git a/src/core/variant/Variant.cpp b/src/core/variant/Variant.cpp
index c86905c..d33cd4f 100644
--- a/src/core/variant/Variant.cpp
+++ b/src/core/variant/Variant.cpp
@@ -16,10 +16,26 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <sstream>
+
+#include <core/Utils.hpp>
+
 #include "Variant.hpp"
 
 namespace ousia {
 
+/* Class Variant::TypeException */
+
+Variant::TypeException::TypeException(Type actualType, Type requestedType)
+    : OusiaException(std::string("Variant: Requested \"") +
+                     Variant::getTypeName(requestedType) +
+                     std::string("\" but is \"") +
+                     Variant::getTypeName(actualType) + std::string("\"")),
+      actualType(actualType),
+      requestedType(requestedType)
+{
+}
+
 /* Class Variant */
 
 const char *Variant::getTypeName(Type type)
@@ -32,7 +48,7 @@ const char *Variant::getTypeName(Type type)
 		case Type::INT:
 			return "integer";
 		case Type::DOUBLE:
-			return "number";
+			return "double";
 		case Type::STRING:
 			return "string";
 		case Type::ARRAY:
@@ -43,16 +59,97 @@ const char *Variant::getTypeName(Type type)
 	return "unknown";
 }
 
-/* Class VariantTypeException */
+Variant::boolType Variant::toBool() const
+{
+	switch (getType()) {
+		case Type::NULLPTR:
+			return false;
+		case Type::BOOL:
+			return asBool();
+		case Type::INT:
+			return asInt() != 0;
+		case Type::DOUBLE:
+			return asDouble() != 0.0;
+		case Type::STRING:
+			return true;
+		case Type::ARRAY:
+			return true;
+		case Type::MAP:
+			return true;
+	}
+	return false;
+}
 
-Variant::TypeException::TypeException(Type actualType, Type requestedType)
-    : OusiaException(std::string("Variant: Requested \"") +
-                     Variant::getTypeName(actualType) +
-                     std::string("\" but is \"") +
-                     Variant::getTypeName(requestedType) + std::string("\"")),
-      actualType(actualType),
-      requestedType(requestedType)
+Variant::intType Variant::toInt() const
 {
+	switch (getType()) {
+		case Type::NULLPTR:
+			return 0;
+		case Type::BOOL:
+			return asBool() ? 1 : 0;
+		case Type::INT:
+			return asInt();
+		case Type::DOUBLE:
+			return asDouble();
+		case Type::STRING:
+			return 0; // TODO: Parse string as int
+		case Type::ARRAY: {
+			const arrayType &a = asArray();
+			return (a.size() == 1) ? a[0].toInt() : 0;
+		}
+		case Type::MAP:
+			return 0;
+	}
+	return false;
 }
+
+Variant::doubleType Variant::toDouble() const
+{
+	switch (getType()) {
+		case Type::NULLPTR:
+			return 0.0;
+		case Type::BOOL:
+			return asBool() ? 1.0 : 0.0;
+		case Type::INT:
+			return asInt();
+		case Type::DOUBLE:
+			return asDouble();
+		case Type::STRING:
+			return 0.0; // TODO: Parse string as double
+		case Type::ARRAY: {
+			const arrayType &a = asArray();
+			return (a.size() == 1) ? a[0].toDouble() : 0;
+		}
+		case Type::MAP:
+			return 0;
+	}
+	return false;
+}
+
+Variant::stringType Variant::toString(bool escape) const
+{
+	switch (getType()) {
+		case Type::NULLPTR:
+			return "null";
+		case Type::BOOL:
+			return asBool() ? "true" : "false";
+		case Type::INT:
+			return std::to_string(asInt());
+		case Type::DOUBLE:
+			return std::to_string(asDouble());
+		case Type::STRING: {
+			// TODO: Use proper serialization function
+			std::stringstream ss;
+			ss << "\"" << asString() << "\"";
+			return ss.str();
+		}
+		case Type::ARRAY:
+			return Utils::join(asArray(), ", ", "[", "]");
+		case Type::MAP:
+			return Utils::join(asMap(), ", ", "{", "}");
+	}
+	return "";
+}
+
 }
 
diff --git a/src/core/variant/Variant.hpp b/src/core/variant/Variant.hpp
index f438d3e..d65e14a 100644
--- a/src/core/variant/Variant.hpp
+++ b/src/core/variant/Variant.hpp
@@ -20,8 +20,8 @@
  * @file Variant.hpp
  *
  * The Variant class is used to efficiently represent a variables of varying
- * type. Variant instances are used to represent user data and to exchange
- * information between the host application and the script clients.
+ * type. Variant instances are used to represent data given by the end user and
+ * to exchange information between the host application and the script clients.
  *
  * @author Andreas Stöckel (astoecke@techfak.uni-bielefeld.de)
  */
@@ -33,6 +33,7 @@
 #include <map>
 #include <string>
 #include <vector>
+#include <ostream>
 
 // TODO: Use
 // http://nikic.github.io/2012/02/02/Pointer-magic-for-efficient-dynamic-value-representations.html
@@ -260,6 +261,11 @@ public:
 	~Variant() { destroy(); }
 
 	/**
+	 * Constructor for null values. Initializes the variant as null value.
+	 */
+	Variant(std::nullptr_t) : ptrVal(nullptr) { setNull(); }
+
+	/**
 	 * Constructor for boolean values.
 	 *
 	 * @param b boolean value.
@@ -294,10 +300,7 @@ public:
 	 *
 	 * @param a is a reference to the array
 	 */
-	Variant(arrayType a) : ptrVal(nullptr)
-	{
-		setArray(std::move(a));
-	}
+	Variant(arrayType a) : ptrVal(nullptr) { setArray(std::move(a)); }
 
 	/**
 	 * Constructor for map values. The given map is copied and managed by the
@@ -305,10 +308,7 @@ public:
 	 *
 	 * @param m is a reference to the map.
 	 */
-	Variant(mapType m) : ptrVal(nullptr)
-	{
-		setMap(std::move(m));
-	}
+	Variant(mapType m) : ptrVal(nullptr) { setMap(std::move(m)); }
 
 	/**
 	 * Copy assignment operator.
@@ -528,6 +528,36 @@ public:
 	mapType &asMap() { return asObj<mapType>(Type::MAP); }
 
 	/**
+	 * Returns the value of the Variant as boolean, performs type conversion.
+	 *
+	 * @return the Variant value converted to a boolean value.
+	 */
+	boolType toBool() const;
+
+	/**
+	 * Returns the value of the Variant as integer, performs type conversion.
+	 *
+	 * @return the Variant value converted to an integer value.
+	 */
+	intType toInt() const;
+
+	/**
+	 * Returns the value of the Variant as double, performs type conversion.
+	 *
+	 * @return the Variant value converted to a double value.
+	 */
+	doubleType toDouble() const;
+
+	/**
+	 * Returns the value of the Variant as string, performs type conversion.
+	 *
+	 * @return the value of the variant as string.
+	 * @param escape if set to true, adds double quotes to strings and escapes
+	 * them properly (resulting in a more or less JSONesque output).
+	 */
+	stringType toString(bool escape = false) const;
+
+	/**
 	 * Sets the variant to null.
 	 */
 	void setNull()
@@ -637,7 +667,26 @@ public:
 	 * Returns the name of the type of this variant instance.
 	 */
 	const char *getTypeName() { return Variant::getTypeName(getType()); }
+
+	/**
+	 * Prints the Variant to the output stream.
+	 */
+	friend std::ostream &operator<<(std::ostream &os, const Variant &v)
+	{
+		return os << v.toString(true);
+	}
+
+	/**
+	 * Prints a key value pair to the output stream.
+	 */
+	friend std::ostream &operator<<(std::ostream &os,
+		                     const mapType::value_type &v)
+	{
+		// TODO: Use proper serialization function
+		return os << "\"" << v.first << "\": " << v.second.toString(true);
+	}
 };
+
 }
 
 #endif /* _OUSIA_VARIANT_HPP_ */