COMMON: Rename Error to ErrorCode, introduce new Error class

2 files changed, 85 insertions, 39 deletions

diff --git a/common/error.cpp b/common/error.cpp
index 6d1e349287..d0e301b091 100644
--- a/common/error.cpp
+++ b/common/error.cpp
@@ -31,44 +31,61 @@
 namespace Common {
 
 /**
- * Error Table: Maps error codes to their default descriptions
+ * Maps an error code to equivalent string description.
+ *
+ * @param errorCode error code to be converted
+ * @return a pointer to string description of the error
  */
-
-struct ErrorMessage {
-	Error error;
-	const char *errMsg;
-};
-
-static const ErrorMessage _errMsgTable[] = {
-	{ kInvalidPathError, _s("Invalid Path") },
-	{ kNoGameDataFoundError, _s("Game Data not found") },
-	{ kUnsupportedGameidError, _s("Game Id not supported") },
-	{ kUnsupportedColorMode, _s("Unsupported Color Mode") },
-
-	{ kReadPermissionDenied, _s("Read permission denied") },
-	{ kWritePermissionDenied, _s("Write permission denied") },
+static String errorToString(ErrorCode errorCode) {
+	switch (errorCode) {
+	case kNoError:
+		return _s("No error");
+	case kInvalidPathError:
+		return _s("Invalid Path");
+	case kNoGameDataFoundError:
+		return _s("Game Data not found");
+	case kUnsupportedGameidError:
+		return _s("Game Id not supported");
+	case kUnsupportedColorMode:
+		return _s("Unsupported Color Mode");
+
+	case kReadPermissionDenied:
+		return _s("Read permission denied");
+	case kWritePermissionDenied:
+		return _s("Write permission denied");
 
 	// The following three overlap a bit with kInvalidPathError and each other. Which to keep?
-	{ kPathDoesNotExist, _s("Path not exists") },
-	{ kPathNotDirectory, _s("Path not a directory") },
-	{ kPathNotFile, _s("Path not a file") },
-
-	{ kCreatingFileFailed, _s("Cannot create file") },
-	{ kReadingFailed, _s("Reading failed") },
-	{ kWritingFailed, _s("Writing data failed") },
-
-	{ kUnknownError, _s("Unknown Error") }
-};
-
-const char *errorToString(Error error) {
-
-	for (int i = 0; i < ARRAYSIZE(_errMsgTable); i++) {
-		if (error == _errMsgTable[i].error) {
-			return _errMsgTable[i].errMsg;
-		}
+	case kPathDoesNotExist:
+		return _s("Path not exists");
+	case kPathNotDirectory:
+		return _s("Path not a directory");
+	case kPathNotFile:
+		return _s("Path not a file");
+
+	case kCreatingFileFailed:
+		return _s("Cannot create file");
+	case kReadingFailed:
+		return _s("Reading failed");
+	case kWritingFailed:
+		return _s("Writing data failed");
+
+	case kUnknownError:
+	case kPluginNotFound:
+	case kPluginNotSupportSaves:
+	case kNoSavesError:
+	case kArgumentNotProcessed:
+	default:
+		return _s("Unknown Error");
 	}
+}
 
-	return _("Unknown Error");
+Error::Error(ErrorCode code)
+	: _code(code), _desc(errorToString(code)) {
 }
 
+Error::Error(ErrorCode code, const String &desc)
+	: _code(code), _desc(errorToString(code) + ": " + desc) {
+}
+
+
 } // End of namespace Common
diff --git a/common/error.h b/common/error.h
index 58343114a2..9d74ccac9b 100644
--- a/common/error.h
+++ b/common/error.h
@@ -26,6 +26,8 @@
 #ifndef COMMON_ERROR_H
 #define COMMON_ERROR_H
 
+#include "common/str.h"
+
 namespace Common {
 
 /**
@@ -43,7 +45,7 @@ namespace Common {
  *       kPathInvalidError would be correct, but these would not be: kInvalidPath,
  *       kPathInvalid, kPathIsInvalid, kInvalidPathError
  */
-enum Error {
+enum ErrorCode {
 	kNoError = 0,				///< No error occurred
 	kInvalidPathError,			///< Engine initialization: Invalid game path was passed
 	kNoGameDataFoundError,		///< Engine initialization: No game data was found in the specified location
@@ -73,12 +75,39 @@ enum Error {
 };
 
 /**
- * Maps an error code to equivalent string description.
- *
- * @param error error code to be converted
- * @return a pointer to string description of the error
+ * An Error instance pairs an error code with string description providing more
+ * details about the error. For every error code, a default description is
+ * provided, but it is possible to optionally augment that description with
+ * extra information when creating a new Error instance.
  */
-const char *errorToString(Error error);
+class Error {
+protected:
+	ErrorCode _code;
+	String _desc;
+public:
+	/**
+	 * Construct a new Error with the specified error code and the default
+	 * error message.
+	 */
+	Error(ErrorCode code = kUnknownError);
+
+	/**
+	 * Construct a new Error with the specified error code and an augmented
+	 * error message. Specifically, the provided extra text is appended
+	 * to the default message, with ": " inserted in between.
+	 */
+	Error(ErrorCode code, const String &extra);
+
+	/**
+	 * Get the description of this error.
+	 */
+	const String &getDesc() const { return _desc; }
+
+	/**
+	 * Get the error code of this error.
+	 */
+	ErrorCode getCode() const { return _code; }
+};
 
 } // End of namespace Common