react-native/React/Fabric/Mounting/RCTMountingManager.mm

/**
 * Copyright (c) 2015-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */

#import "RCTMountingManager.h"

#import <fabric/core/LayoutableShadowNode.h>
#import <React/RCTAssert.h>
#import <React/RCTUtils.h>

#import "RCTComponentViewProtocol.h"
#import "RCTComponentViewRegistry.h"
#import "RCTMountItemProtocol.h"

#import "RCTCreateMountItem.h"
#import "RCTConversions.h"
#import "RCTDeleteMountItem.h"
#import "RCTInsertMountItem.h"
#import "RCTRemoveMountItem.h"
#import "RCTUpdatePropsMountItem.h"
#import "RCTUpdateEventEmitterMountItem.h"
#import "RCTUpdateLocalDataMountItem.h"
#import "RCTUpdateLayoutMetricsMountItem.h"

using namespace facebook::react;

@implementation RCTMountingManager

- (instancetype)init
{
  if (self = [super init]) {
    _componentViewRegistry = [[RCTComponentViewRegistry alloc] init];
  }

  return self;
}

- (void)performTransactionWithMutations:(facebook::react::ShadowViewMutationList)mutations
                                rootTag:(ReactTag)rootTag
{
  NSMutableArray<RCTMountItemProtocol> *mountItems =
    [[NSMutableArray<RCTMountItemProtocol> alloc] initWithCapacity:mutations.size() * 2 /* ~ the worst case */];

  for (const auto &mutation : mutations) {
    switch (mutation.type) {
      case ShadowViewMutation::Create: {
        NSString *componentName = RCTNSStringFromString(mutation.newChildShadowView.componentName, NSASCIIStringEncoding);
        RCTCreateMountItem *mountItem =
          [[RCTCreateMountItem alloc] initWithComponentName:componentName
                                                        tag:mutation.newChildShadowView.tag];
        [mountItems addObject:mountItem];
        break;
      }

      case ShadowViewMutation::Delete: {
        NSString *componentName = RCTNSStringFromString(mutation.oldChildShadowView.componentName, NSASCIIStringEncoding);
        RCTDeleteMountItem *mountItem =
          [[RCTDeleteMountItem alloc] initWithComponentName:componentName
                                                        tag:mutation.oldChildShadowView.tag];
        [mountItems addObject:mountItem];
        break;
      }

      case ShadowViewMutation::Insert: {
        // Props
        [mountItems addObject:[[RCTUpdatePropsMountItem alloc] initWithTag:mutation.newChildShadowView.tag
                                                                  oldProps:nullptr
                                                                  newProps:mutation.newChildShadowView.props]];

        // EventEmitter
        [mountItems addObject:[[RCTUpdateEventEmitterMountItem alloc] initWithTag:mutation.newChildShadowView.tag
                                                                     eventEmitter:mutation.newChildShadowView.eventEmitter]];

        // LocalData
        if (mutation.newChildShadowView.localData) {
          [mountItems addObject:[[RCTUpdateLocalDataMountItem alloc] initWithTag:mutation.newChildShadowView.tag
                                                                    oldLocalData:nullptr
                                                                    newLocalData:mutation.newChildShadowView.localData]];
        }

        // Layout
        if (mutation.newChildShadowView.layoutMetrics != EmptyLayoutMetrics) {
          [mountItems addObject:[[RCTUpdateLayoutMetricsMountItem alloc] initWithTag:mutation.newChildShadowView.tag
                                                                    oldLayoutMetrics:{}
                                                                    newLayoutMetrics:mutation.newChildShadowView.layoutMetrics]];
        }

        // Insertion
        RCTInsertMountItem *mountItem =
          [[RCTInsertMountItem alloc] initWithChildTag:mutation.newChildShadowView.tag
                                             parentTag:mutation.parentShadowView.tag
                                                 index:mutation.index];
        [mountItems addObject:mountItem];

        break;
      }

      case ShadowViewMutation::Remove: {
        RCTRemoveMountItem *mountItem =
          [[RCTRemoveMountItem alloc] initWithChildTag:mutation.oldChildShadowView.tag
                                             parentTag:mutation.parentShadowView.tag
                                                 index:mutation.index];
        [mountItems addObject:mountItem];
        break;
      }

      case ShadowViewMutation::Update: {
        auto oldChildShadowView = mutation.oldChildShadowView;
        auto newChildShadowView = mutation.newChildShadowView;

        // Props
        if (oldChildShadowView.props != newChildShadowView.props) {
          RCTUpdatePropsMountItem *mountItem =
            [[RCTUpdatePropsMountItem alloc] initWithTag:mutation.oldChildShadowView.tag
                                                oldProps:mutation.oldChildShadowView.props
                                                newProps:mutation.newChildShadowView.props];
          [mountItems addObject:mountItem];
        }

        // EventEmitter
        if (oldChildShadowView.eventEmitter != newChildShadowView.eventEmitter) {
          RCTUpdateEventEmitterMountItem *mountItem =
            [[RCTUpdateEventEmitterMountItem alloc] initWithTag:mutation.oldChildShadowView.tag
                                                   eventEmitter:mutation.oldChildShadowView.eventEmitter];
          [mountItems addObject:mountItem];
        }

        // LocalData
        if (oldChildShadowView.localData != newChildShadowView.localData) {
          RCTUpdateLocalDataMountItem *mountItem =
            [[RCTUpdateLocalDataMountItem alloc] initWithTag:newChildShadowView.tag
                                                oldLocalData:oldChildShadowView.localData
                                                newLocalData:newChildShadowView.localData];
          [mountItems addObject:mountItem];
        }

        // Layout
        if (oldChildShadowView.layoutMetrics != newChildShadowView.layoutMetrics) {
          RCTUpdateLayoutMetricsMountItem *mountItem =
            [[RCTUpdateLayoutMetricsMountItem alloc] initWithTag:mutation.oldChildShadowView.tag
                                                oldLayoutMetrics:oldChildShadowView.layoutMetrics
                                                newLayoutMetrics:newChildShadowView.layoutMetrics];
          [mountItems addObject:mountItem];
        }

        break;
      }
    }
  }

  RCTExecuteOnMainQueue(^{
    [self _performMountItems:mountItems rootTag:rootTag];
  });
}

- (void)_performMountItems:(NSArray<RCTMountItemProtocol> *)mountItems
                   rootTag:(ReactTag)rootTag
{
  RCTAssertMainQueue();

  [self.delegate mountingManager:self willMountComponentsWithRootTag:rootTag];

  for (id<RCTMountItemProtocol> mountItem in mountItems) {
    [mountItem executeWithRegistry:_componentViewRegistry];
  }

  [self.delegate mountingManager:self didMountComponentsWithRootTag:rootTag];
}

- (void)preliminaryCreateComponentViewWithName:(NSString *)componentName
{
  RCTExecuteOnMainQueue(^{
    [self->_componentViewRegistry preliminaryCreateComponentViewWithName:componentName];
  });
}

@end