Generate objc handler for commands

Summary:
These functions will be called by components like this:
```
- (void)handleCommand:(NSString const *)commandName args:(NSArray const *)args
{
  ViewNativeComponentHandleCommand(self, commandName, args);
}
```

Codegen currently supports commands with ints and bools as arguments. Will add more types in follow up diffs.

Reviewed By: JoshuaGross

Differential Revision: D16509123

fbshipit-source-id: c3071ce3b5da215bb8747216e57026a69a89eff0

packages/react-native-codegen/src/generators/components/GenerateComponentHObjCpp.js

@@ -11,6 +11,7 @@
 'use strict';
 
 import type {
+  CommandTypeShape,
   ComponentShape,
   SchemaType,
   CommandsFunctionTypeParamAnnotation,
@@ -18,12 +19,69 @@ import type {
 
 type FilesOutput = Map<string, string>;
 
+function getOrdinalNumber(num: number): string {
+  switch (num) {
+    case 1:
+      return '1st';
+    case 2:
+      return '2nd';
+    case 3:
+      return '3rd';
+  }
+
+  if (num <= 20) {
+    return `${num}th`;
+  }
+
+  return 'unknown';
+}
+
 const protocolTemplate = `
 @protocol ::_COMPONENT_NAME_::ViewProtocol <NSObject>
 ::_METHODS_::
 @end
 `.trim();
 
+const commandHandlerIfCaseConvertArgTemplate = `
+#if RCT_DEBUG
+  NSObject *arg::_ARG_NUMBER_:: = args[::_ARG_NUMBER_::];
+  if (!RCTValidateTypeOfViewCommandArgument(arg::_ARG_NUMBER_::, ::_EXPECTED_KIND_::, @"::_EXPECTED_KIND_STRING_::", @"::_COMPONENT_NAME_::", commandName, @"::_ARG_NUMBER_STR_::")) {
+    return;
+  }
+#endif
+  ::_ARG_CONVERSION_::
+`.trim();
+
+const commandHandlerIfCaseTemplate = `
+if ([commandName isEqualToString:@"::_COMMAND_NAME_::"]) {
+#if RCT_DEBUG
+  if ([args count] != ::_NUM_ARGS_::) {
+    RCTLogError(@"%@ command %@ received %d arguments, expected %d.", @"::_COMPONENT_NAME_::", commandName, (int)[args count], ::_NUM_ARGS_::);
+    return;
+  }
+#endif
+
+::_CONVERT_ARGS_::
+
+  ::_COMMAND_CALL_::
+  return;
+}
+`.trim();
+
+const commandHandlerTemplate = `
+RCT_EXTERN inline void ::_COMPONENT_NAME_::HandleCommand(
+  id<::_COMPONENT_NAME_::ViewProtocol> componentView,
+  NSString const *commandName,
+  NSArray const *args)
+{
+  ::_IF_CASES_::
+
+#if RCT_DEBUG
+  RCTLogError(@"%@ received command %@, which is not a supported command.", @"::_COMPONENT_NAME_::", commandName);
+#endif
+}
+`.trim();
+
 const template = `
 /**
 * Copyright (c) Facebook, Inc. and its affiliates.
@@ -55,6 +113,49 @@ function getObjCParamType(param: CommandsFunctionTypeParamAnnotation): string {
   }
 }
 
+function getObjCExpectedKindParamType(
+  param: CommandsFunctionTypeParamAnnotation,
+): string {
+  switch (param.typeAnnotation.type) {
+    case 'BooleanTypeAnnotation':
+      return '[NSNumber class]';
+    case 'Int32TypeAnnotation':
+      return '[NSNumber class]';
+    default:
+      (param.typeAnnotation.type: empty);
+      throw new Error('Received invalid param type annotation');
+  }
+}
+
+function getReadableExpectedKindParamType(
+  param: CommandsFunctionTypeParamAnnotation,
+): string {
+  switch (param.typeAnnotation.type) {
+    case 'BooleanTypeAnnotation':
+      return 'boolean';
+    case 'Int32TypeAnnotation':
+      return 'number';
+    default:
+      (param.typeAnnotation.type: empty);
+      throw new Error('Received invalid param type annotation');
+  }
+}
+
+function getObjCRightHandAssignmentParamType(
+  param: CommandsFunctionTypeParamAnnotation,
+  index: number,
+): string {
+  switch (param.typeAnnotation.type) {
+    case 'BooleanTypeAnnotation':
+      return `[(NSNumber *)arg${index} boolValue]`;
+    case 'Int32TypeAnnotation':
+      return `[(NSNumber *)arg${index} intValue]`;
+    default:
+      (param.typeAnnotation.type: empty);
+      throw new Error('Received invalid param type annotation');
+  }
+}
+
 function generateProtocol(
   component: ComponentShape,
   componentName: string,
@@ -84,6 +185,75 @@ function generateProtocol(
     .replace('::_METHODS_::', commands);
 }
 
+function generateConvertAndValidateParam(
+  param: CommandsFunctionTypeParamAnnotation,
+  index: number,
+  componentName: string,
+): string {
+  const leftSideType = getObjCParamType(param);
+  const expectedKind = getObjCExpectedKindParamType(param);
+  const expectedKindString = getReadableExpectedKindParamType(param);
+  const argConversion = `${leftSideType} ${
+    param.name
+  } = ${getObjCRightHandAssignmentParamType(param, index)};`;
+
+  return commandHandlerIfCaseConvertArgTemplate
+    .replace(/::_COMPONENT_NAME_::/g, componentName)
+    .replace('::_ARG_CONVERSION_::', argConversion)
+    .replace(/::_ARG_NUMBER_::/g, '' + index)
+    .replace('::_ARG_NUMBER_STR_::', getOrdinalNumber(index + 1))
+    .replace('::_EXPECTED_KIND_::', expectedKind)
+    .replace('::_EXPECTED_KIND_STRING_::', expectedKindString);
+}
+
+function generateCommandIfCase(
+  command: CommandTypeShape,
+  componentName: string,
+) {
+  const params = command.typeAnnotation.params;
+
+  const convertArgs = params
+    .map((param, index) =>
+      generateConvertAndValidateParam(param, index, componentName),
+    )
+    .join('\n\n')
+    .trim();
+
+  const commandCallArgs =
+    params.length === 0
+      ? ''
+      : params
+          .map((param, index) => {
+            return `${index === 0 ? '' : param.name}:${param.name}`;
+          })
+          .join(' ');
+  const commandCall = `[componentView ${command.name}${commandCallArgs}]`;
+
+  return commandHandlerIfCaseTemplate
+    .replace(/::_COMPONENT_NAME_::/g, componentName)
+    .replace(/::_COMMAND_NAME_::/g, command.name)
+    .replace(/::_NUM_ARGS_::/g, '' + params.length)
+    .replace('::_CONVERT_ARGS_::', convertArgs)
+    .replace('::_COMMAND_CALL_::', commandCall);
+}
+
+function generateCommandHandler(
+  component: ComponentShape,
+  componentName: string,
+): ?string {
+  if (component.commands.length === 0) {
+    return null;
+  }
+
+  const ifCases = component.commands
+    .map(command => generateCommandIfCase(command, componentName))
+    .join('\n\n');
+
+  return commandHandlerTemplate
+    .replace(/::_COMPONENT_NAME_::/g, componentName)
+    .replace('::_IF_CASES_::', ifCases);
+}
+
 module.exports = {
   generate(libraryName: string, schema: SchemaType): FilesOutput {
     const fileName = 'ComponentViewHelpers.h';
@@ -98,7 +268,12 @@ module.exports = {
 
         return Object.keys(components)
           .map(componentName => {
-            return generateProtocol(components[componentName], componentName);
+            return [
+              generateProtocol(components[componentName], componentName),
+              generateCommandHandler(components[componentName], componentName),
+            ]
+              .join('\n\n')
+              .trim();
           })
           .join('\n\n');
       })

packages/react-native-codegen/src/generators/components/__tests__/__snapshots__/GenerateComponentHObjCpp-test.js.snap

@@ -90,6 +90,86 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)scrollTo:(NSInteger)y animated:(BOOL)animated;
 @end
 
+RCT_EXTERN inline void CommandNativeComponentHandleCommand(
+  id<CommandNativeComponentViewProtocol> componentView,
+  NSString const *commandName,
+  NSArray const *args)
+{
+  if ([commandName isEqualToString:@\\"flashScrollIndicators\\"]) {
+#if RCT_DEBUG
+  if ([args count] != 0) {
+    RCTLogError(@\\"%@ command %@ received %d arguments, expected %d.\\", @\\"CommandNativeComponent\\", commandName, (int)[args count], 0);
+    return;
+  }
+#endif
+
+
+
+  [componentView flashScrollIndicators]
+  return;
+}
+
+if ([commandName isEqualToString:@\\"hotspotUpdate\\"]) {
+#if RCT_DEBUG
+  if ([args count] != 2) {
+    RCTLogError(@\\"%@ command %@ received %d arguments, expected %d.\\", @\\"CommandNativeComponent\\", commandName, (int)[args count], 2);
+    return;
+  }
+#endif
+
+#if RCT_DEBUG
+  NSObject *arg0 = args[0];
+  if (!RCTValidateTypeOfViewCommandArgument(arg0, [NSNumber class], @\\"number\\", @\\"CommandNativeComponent\\", commandName, @\\"1st\\")) {
+    return;
+  }
+#endif
+  NSInteger x = [(NSNumber *)arg0 intValue];
+
+#if RCT_DEBUG
+  NSObject *arg1 = args[1];
+  if (!RCTValidateTypeOfViewCommandArgument(arg1, [NSNumber class], @\\"number\\", @\\"CommandNativeComponent\\", commandName, @\\"2nd\\")) {
+    return;
+  }
+#endif
+  NSInteger y = [(NSNumber *)arg1 intValue];
+
+  [componentView hotspotUpdate:x y:y]
+  return;
+}
+
+if ([commandName isEqualToString:@\\"scrollTo\\"]) {
+#if RCT_DEBUG
+  if ([args count] != 2) {
+    RCTLogError(@\\"%@ command %@ received %d arguments, expected %d.\\", @\\"CommandNativeComponent\\", commandName, (int)[args count], 2);
+    return;
+  }
+#endif
+
+#if RCT_DEBUG
+  NSObject *arg0 = args[0];
+  if (!RCTValidateTypeOfViewCommandArgument(arg0, [NSNumber class], @\\"number\\", @\\"CommandNativeComponent\\", commandName, @\\"1st\\")) {
+    return;
+  }
+#endif
+  NSInteger y = [(NSNumber *)arg0 intValue];
+
+#if RCT_DEBUG
+  NSObject *arg1 = args[1];
+  if (!RCTValidateTypeOfViewCommandArgument(arg1, [NSNumber class], @\\"boolean\\", @\\"CommandNativeComponent\\", commandName, @\\"2nd\\")) {
+    return;
+  }
+#endif
+  BOOL animated = [(NSNumber *)arg1 boolValue];
+
+  [componentView scrollTo:y animated:animated]
+  return;
+}
+
+#if RCT_DEBUG
+  RCTLogError(@\\"%@ received command %@, which is not a supported command.\\", @\\"CommandNativeComponent\\", commandName);
+#endif
+}
+
 NS_ASSUME_NONNULL_END",
 }
 `;
@@ -113,6 +193,44 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)hotspotUpdate:(NSInteger)x y:(NSInteger)y;
 @end
 
+RCT_EXTERN inline void CommandNativeComponentHandleCommand(
+  id<CommandNativeComponentViewProtocol> componentView,
+  NSString const *commandName,
+  NSArray const *args)
+{
+  if ([commandName isEqualToString:@\\"hotspotUpdate\\"]) {
+#if RCT_DEBUG
+  if ([args count] != 2) {
+    RCTLogError(@\\"%@ command %@ received %d arguments, expected %d.\\", @\\"CommandNativeComponent\\", commandName, (int)[args count], 2);
+    return;
+  }
+#endif
+
+#if RCT_DEBUG
+  NSObject *arg0 = args[0];
+  if (!RCTValidateTypeOfViewCommandArgument(arg0, [NSNumber class], @\\"number\\", @\\"CommandNativeComponent\\", commandName, @\\"1st\\")) {
+    return;
+  }
+#endif
+  NSInteger x = [(NSNumber *)arg0 intValue];
+
+#if RCT_DEBUG
+  NSObject *arg1 = args[1];
+  if (!RCTValidateTypeOfViewCommandArgument(arg1, [NSNumber class], @\\"number\\", @\\"CommandNativeComponent\\", commandName, @\\"2nd\\")) {
+    return;
+  }
+#endif
+  NSInteger y = [(NSNumber *)arg1 intValue];
+
+  [componentView hotspotUpdate:x y:y]
+  return;
+}
+
+#if RCT_DEBUG
+  RCTLogError(@\\"%@ received command %@, which is not a supported command.\\", @\\"CommandNativeComponent\\", commandName);
+#endif
+}
+
 NS_ASSUME_NONNULL_END",
 }
 `;