THRIFT-2905 Cocoa compiler should have option to produce "modern" Objective-C
Client: Cocoa (ObjectiveC & Swift)
Author: Kevin Wooten <kevin@wooten.com>

This closes #539
diff --git a/lib/cocoa/src/TApplicationError.m b/lib/cocoa/src/TApplicationError.m
new file mode 100644
index 0000000..080bc0b
--- /dev/null
+++ b/lib/cocoa/src/TApplicationError.m
@@ -0,0 +1,231 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#import "TApplicationError.h"
+#import "TProtocolUtil.h"
+
+
+NSString *TApplicationErrorDomain = @"TApplicationErrorDomain";
+
+
+NSString *TApplicationErrorNameKey = @"name";
+NSString *TApplicationErrorReasonKey = @"reason";
+NSString *TApplicationErrorMethodKey = @"method";
+
+
+@implementation NSError (TApplicationError)
+
+-(NSString *) reason
+{
+  return self.userInfo[TApplicationErrorReasonKey];
+}
+
+-(NSString *) name
+{
+  return self.userInfo[TApplicationErrorNameKey];
+}
+
++(instancetype) errorWithType:(TApplicationError)type reason:(NSString *)reason
+{
+  NSString *name;
+  switch (type) {
+  case TApplicationErrorUnknownMethod:
+    name = @"Unknown Method";
+    break;
+
+  case TApplicationErrorInvalidMessageType:
+    name = @"Invalid Message Type";
+    break;
+
+  case TApplicationErrorWrongMethodName:
+    name = @"Wrong Method Name";
+    break;
+
+  case TApplicationErrorBadSequenceId:
+    name = @"Bad Sequence ID";
+    break;
+
+  case TApplicationErrorMissingResult:
+    name = @"Missing Result";
+    break;
+
+  case TApplicationErrorInternalError:
+    name = @"Internal Error";
+    break;
+
+  case TApplicationErrorProtocolError:
+    name = @"Protocol Error";
+    break;
+
+  case TApplicationErrorInvalidTransform:
+    name = @"Invalid Transform";
+    break;
+
+  case TApplicationErrorInvalidProtocol:
+    name = @"Invalid Protocol";
+    break;
+
+  case TApplicationErrorUnsupportedClientType:
+    name = @"Unsupported Client Type";
+    break;
+
+  default:
+    name = @"Unknown";
+    break;
+  }
+
+  NSDictionary *userInfo;
+  if (reason) {
+    userInfo = @{TApplicationErrorNameKey:name,
+                 TApplicationErrorReasonKey:reason};
+  }
+  else {
+    userInfo = @{TApplicationErrorNameKey:name};
+  }
+
+  return [NSError errorWithDomain:TApplicationErrorDomain
+                             code:type
+                         userInfo:userInfo];
+}
+
+
++(instancetype) read:(id<TProtocol>)protocol
+{
+  NSString *reason = nil;
+  SInt32 type = TApplicationErrorUnknown;
+  SInt32 fieldType;
+  SInt32 fieldID;
+
+  NSError *error;
+  if (![protocol readStructBeginReturningName:NULL error:&error]) {
+    return error;
+  }
+
+  while (true) {
+
+    if (![protocol readFieldBeginReturningName:NULL
+                                          type:&fieldType
+                                       fieldID:&fieldID
+                                         error:&error])
+    {
+      return error;
+    }
+
+    if (fieldType == TTypeSTOP) {
+      break;
+    }
+
+    switch (fieldID) {
+    case 1:
+      if (fieldType == TTypeSTRING) {
+        if (![protocol readString:&reason error:&error]) {
+          return error;
+        }
+      }
+      else {
+        if (![TProtocolUtil skipType:fieldType onProtocol:protocol error:&error]) {
+          return error;
+        }
+      }
+      break;
+
+    case 2:
+      if (fieldType == TTypeI32) {
+        if (![protocol readI32:&type error:&error]) {
+          return error;
+        }
+      }
+      else {
+        if (![TProtocolUtil skipType:fieldType onProtocol:protocol error:&error]) {
+          return error;
+        }
+      }
+      break;
+
+    default:
+      if (![TProtocolUtil skipType:fieldType onProtocol:protocol error:&error]) {
+        return error;
+      }
+      break;
+    }
+    if (![protocol readFieldEnd:&error]) {
+      return error;
+    }
+
+  }
+
+  if (![protocol readStructEnd:&error]) {
+    return error;
+  }
+
+  return [NSError errorWithType:type reason:reason];
+}
+
+
+-(BOOL) write:(id<TProtocol>)protocol error:(NSError *__autoreleasing *)error
+{
+  if (![protocol writeStructBeginWithName:@"TApplicationException" error:error]) {
+    return NO;
+  }
+
+  if (self.localizedDescription != nil) {
+    if (![protocol writeFieldBeginWithName:@"message"
+                                      type:TTypeSTRING
+                                   fieldID:1 error:error])
+    {
+      return NO;
+    }
+
+    if (![protocol writeString:self.localizedDescription error:error]) {
+      return NO;
+    }
+
+    if (![protocol writeFieldEnd:error]) {
+      return NO;
+    }
+  }
+
+  if (![protocol writeFieldBeginWithName:@"type"
+                                    type:TTypeI32
+                                 fieldID:2
+                                   error:error])
+  {
+    return NO;
+  }
+
+  if (![protocol writeI32:(SInt32)self.code error:error]) {
+    return NO;
+  }
+
+  if (![protocol writeFieldEnd:error]) {
+    return NO;
+  }
+
+  if (![protocol writeFieldStop:error]) {
+    return NO;
+  }
+
+  if (![protocol writeStructEnd:error]) {
+    return NO;
+  }
+
+  return YES;
+}
+
+@end