Swiftgram/AsyncDisplayKit/Private/_ASHierarchyChangeSet.m
2015-11-26 10:46:26 -08:00

367 lines
13 KiB
Objective-C

//
// _ASHierarchyChangeSet.m
// AsyncDisplayKit
//
// Created by Adlai Holler on 9/29/15.
// Copyright © 2015 Facebook. All rights reserved.
//
#import "_ASHierarchyChangeSet.h"
#import "ASInternalHelpers.h"
@interface _ASHierarchySectionChange ()
- (instancetype)initWithChangeType:(_ASHierarchyChangeType)changeType indexSet:(NSIndexSet *)indexSet animationOptions:(ASDataControllerAnimationOptions)animationOptions;
/**
On return `changes` is sorted according to the change type with changes coalesced by animationOptions
Assumes: `changes` is [_ASHierarchySectionChange] all with the same changeType
*/
+ (void)sortAndCoalesceChanges:(NSMutableArray *)changes;
/// Returns all the indexes from all the `indexSet`s of the given `_ASHierarchySectionChange` objects.
+ (NSMutableIndexSet *)allIndexesInChanges:(NSArray *)changes;
@end
@interface _ASHierarchyItemChange ()
- (instancetype)initWithChangeType:(_ASHierarchyChangeType)changeType indexPaths:(NSArray *)indexPaths animationOptions:(ASDataControllerAnimationOptions)animationOptions presorted:(BOOL)presorted;
/**
On return `changes` is sorted according to the change type with changes coalesced by animationOptions
Assumes: `changes` is [_ASHierarchyItemChange] all with the same changeType
*/
+ (void)sortAndCoalesceChanges:(NSMutableArray *)changes ignoringChangesInSections:(NSIndexSet *)sections;
@end
@interface _ASHierarchyChangeSet ()
@property (nonatomic, strong, readonly) NSMutableArray *insertItemChanges;
@property (nonatomic, strong, readonly) NSMutableArray *deleteItemChanges;
@property (nonatomic, strong, readonly) NSMutableArray *reloadItemChanges;
@property (nonatomic, strong, readonly) NSMutableArray *insertSectionChanges;
@property (nonatomic, strong, readonly) NSMutableArray *deleteSectionChanges;
@property (nonatomic, strong, readonly) NSMutableArray *reloadSectionChanges;
@end
@implementation _ASHierarchyChangeSet
- (instancetype)init
{
self = [super init];
if (self) {
_insertItemChanges = [NSMutableArray new];
_deleteItemChanges = [NSMutableArray new];
_reloadItemChanges = [NSMutableArray new];
_insertSectionChanges = [NSMutableArray new];
_deleteSectionChanges = [NSMutableArray new];
_reloadSectionChanges = [NSMutableArray new];
}
return self;
}
#pragma mark External API
- (void)markCompleted
{
NSAssert(!_completed, @"Attempt to mark already-completed changeset as completed.");
_completed = YES;
[self _sortAndCoalesceChangeArrays];
}
- (NSArray *)sectionChangesOfType:(_ASHierarchyChangeType)changeType
{
[self _ensureCompleted];
switch (changeType) {
case _ASHierarchyChangeTypeInsert:
return _insertSectionChanges;
case _ASHierarchyChangeTypeReload:
return _reloadSectionChanges;
case _ASHierarchyChangeTypeDelete:
return _deleteSectionChanges;
default:
NSAssert(NO, @"Request for section changes with invalid type: %lu", (long)changeType);
}
}
- (NSArray *)itemChangesOfType:(_ASHierarchyChangeType)changeType
{
[self _ensureCompleted];
switch (changeType) {
case _ASHierarchyChangeTypeInsert:
return _insertItemChanges;
case _ASHierarchyChangeTypeReload:
return _reloadItemChanges;
case _ASHierarchyChangeTypeDelete:
return _deleteItemChanges;
default:
NSAssert(NO, @"Request for item changes with invalid type: %lu", (long)changeType);
}
}
- (NSInteger)newSectionForOldSection:(NSInteger)oldSection
{
[self _ensureCompleted];
if ([_deletedSections containsIndex:oldSection]) {
return NSNotFound;
}
NSInteger indexAfterDeletes = oldSection - [_deletedSections countOfIndexesInRange:NSMakeRange(0, oldSection)];
return indexAfterDeletes + [_insertedSections countOfIndexesInRange:NSMakeRange(0, indexAfterDeletes)];
}
- (void)deleteItems:(NSArray *)indexPaths animationOptions:(ASDataControllerAnimationOptions)options
{
[self _ensureNotCompleted];
_ASHierarchyItemChange *change = [[_ASHierarchyItemChange alloc] initWithChangeType:_ASHierarchyChangeTypeDelete indexPaths:indexPaths animationOptions:options presorted:NO];
[_deleteItemChanges addObject:change];
}
- (void)deleteSections:(NSIndexSet *)sections animationOptions:(ASDataControllerAnimationOptions)options
{
[self _ensureNotCompleted];
_ASHierarchySectionChange *change = [[_ASHierarchySectionChange alloc] initWithChangeType:_ASHierarchyChangeTypeDelete indexSet:sections animationOptions:options];
[_deleteSectionChanges addObject:change];
}
- (void)insertItems:(NSArray *)indexPaths animationOptions:(ASDataControllerAnimationOptions)options
{
[self _ensureNotCompleted];
_ASHierarchyItemChange *change = [[_ASHierarchyItemChange alloc] initWithChangeType:_ASHierarchyChangeTypeInsert indexPaths:indexPaths animationOptions:options presorted:NO];
[_insertItemChanges addObject:change];
}
- (void)insertSections:(NSIndexSet *)sections animationOptions:(ASDataControllerAnimationOptions)options
{
[self _ensureNotCompleted];
_ASHierarchySectionChange *change = [[_ASHierarchySectionChange alloc] initWithChangeType:_ASHierarchyChangeTypeInsert indexSet:sections animationOptions:options];
[_insertSectionChanges addObject:change];
}
- (void)reloadItems:(NSArray *)indexPaths animationOptions:(ASDataControllerAnimationOptions)options
{
[self _ensureNotCompleted];
_ASHierarchyItemChange *change = [[_ASHierarchyItemChange alloc] initWithChangeType:_ASHierarchyChangeTypeReload indexPaths:indexPaths animationOptions:options presorted:NO];
[_reloadItemChanges addObject:change];
}
- (void)reloadSections:(NSIndexSet *)sections animationOptions:(ASDataControllerAnimationOptions)options
{
[self _ensureNotCompleted];
_ASHierarchySectionChange *change = [[_ASHierarchySectionChange alloc] initWithChangeType:_ASHierarchyChangeTypeReload indexSet:sections animationOptions:options];
[_reloadSectionChanges addObject:change];
}
#pragma mark Private
- (BOOL)_ensureNotCompleted
{
NSAssert(!_completed, @"Attempt to modify completed changeset %@", self);
return !_completed;
}
- (BOOL)_ensureCompleted
{
NSAssert(_completed, @"Attempt to process incomplete changeset %@", self);
return _completed;
}
- (void)_sortAndCoalesceChangeArrays
{
@autoreleasepool {
[_ASHierarchySectionChange sortAndCoalesceChanges:_deleteSectionChanges];
[_ASHierarchySectionChange sortAndCoalesceChanges:_insertSectionChanges];
[_ASHierarchySectionChange sortAndCoalesceChanges:_reloadSectionChanges];
_deletedSections = [[_ASHierarchySectionChange allIndexesInChanges:_deleteSectionChanges] copy];
_insertedSections = [[_ASHierarchySectionChange allIndexesInChanges:_insertSectionChanges] copy];
_reloadedSections = [[_ASHierarchySectionChange allIndexesInChanges:_reloadSectionChanges] copy];
// These are invalid old section indexes.
NSMutableIndexSet *deletedOrReloaded = [_deletedSections mutableCopy];
[deletedOrReloaded addIndexes:_reloadedSections];
// These are invalid new section indexes.
NSMutableIndexSet *insertedOrReloaded = [_insertedSections mutableCopy];
// Get the new section that each reloaded section index corresponds to.
[_reloadedSections enumerateIndexesUsingBlock:^(NSUInteger oldIndex, __unused BOOL * stop) {
NSUInteger newIndex = [self newSectionForOldSection:oldIndex];
if (newIndex != NSNotFound) {
[insertedOrReloaded addIndex:newIndex];
}
}];
// Ignore item reloads/deletes in reloaded/deleted sections.
[_ASHierarchyItemChange sortAndCoalesceChanges:_deleteItemChanges ignoringChangesInSections:deletedOrReloaded];
[_ASHierarchyItemChange sortAndCoalesceChanges:_reloadItemChanges ignoringChangesInSections:deletedOrReloaded];
// Ignore item inserts in reloaded(new)/inserted sections.
[_ASHierarchyItemChange sortAndCoalesceChanges:_insertItemChanges ignoringChangesInSections:insertedOrReloaded];
}
}
@end
@implementation _ASHierarchySectionChange
- (instancetype)initWithChangeType:(_ASHierarchyChangeType)changeType indexSet:(NSIndexSet *)indexSet animationOptions:(ASDataControllerAnimationOptions)animationOptions
{
self = [super init];
if (self) {
_changeType = changeType;
_indexSet = indexSet;
_animationOptions = animationOptions;
}
return self;
}
+ (void)sortAndCoalesceChanges:(NSMutableArray *)changes
{
if (changes.count < 1) {
return;
}
_ASHierarchyChangeType type = [changes.firstObject changeType];
// Lookup table [Int: AnimationOptions]
NSMutableDictionary *animationOptions = [NSMutableDictionary new];
// All changed indexes, sorted
NSMutableIndexSet *allIndexes = [NSMutableIndexSet new];
for (_ASHierarchySectionChange *change in changes) {
[change.indexSet enumerateIndexesUsingBlock:^(NSUInteger idx, __unused BOOL *stop) {
animationOptions[@(idx)] = @(change.animationOptions);
}];
[allIndexes addIndexes:change.indexSet];
}
// Create new changes by grouping sorted changes by animation option
NSMutableArray *result = [NSMutableArray new];
__block ASDataControllerAnimationOptions currentOptions = 0;
NSMutableIndexSet *currentIndexes = [NSMutableIndexSet indexSet];
NSEnumerationOptions options = type == _ASHierarchyChangeTypeDelete ? NSEnumerationReverse : kNilOptions;
[allIndexes enumerateIndexesWithOptions:options usingBlock:^(NSUInteger idx, __unused BOOL * stop) {
ASDataControllerAnimationOptions options = [animationOptions[@(idx)] integerValue];
// End the previous group if needed.
if (options != currentOptions && currentIndexes.count > 0) {
_ASHierarchySectionChange *change = [[_ASHierarchySectionChange alloc] initWithChangeType:type indexSet:[currentIndexes copy] animationOptions:currentOptions];
[result addObject:change];
[currentIndexes removeAllIndexes];
}
// Start a new group if needed.
if (currentIndexes.count == 0) {
currentOptions = options;
}
[currentIndexes addIndex:idx];
}];
// Finish up the last group.
if (currentIndexes.count > 0) {
_ASHierarchySectionChange *change = [[_ASHierarchySectionChange alloc] initWithChangeType:type indexSet:[currentIndexes copy] animationOptions:currentOptions];
[result addObject:change];
}
[changes setArray:result];
}
+ (NSMutableIndexSet *)allIndexesInChanges:(NSArray *)changes
{
NSMutableIndexSet *indexes = [NSMutableIndexSet indexSet];
for (_ASHierarchySectionChange *change in changes) {
[indexes addIndexes:change.indexSet];
}
return indexes;
}
@end
@implementation _ASHierarchyItemChange
- (instancetype)initWithChangeType:(_ASHierarchyChangeType)changeType indexPaths:(NSArray *)indexPaths animationOptions:(ASDataControllerAnimationOptions)animationOptions presorted:(BOOL)presorted
{
self = [super init];
if (self) {
_changeType = changeType;
if (presorted) {
_indexPaths = indexPaths;
} else {
SEL sorting = changeType == _ASHierarchyChangeTypeDelete ? @selector(asdk_inverseCompare:) : @selector(compare:);
_indexPaths = [indexPaths sortedArrayUsingSelector:sorting];
}
_animationOptions = animationOptions;
}
return self;
}
+ (void)sortAndCoalesceChanges:(NSMutableArray *)changes ignoringChangesInSections:(NSIndexSet *)sections
{
if (changes.count < 1) {
return;
}
_ASHierarchyChangeType type = [changes.firstObject changeType];
// Lookup table [NSIndexPath: AnimationOptions]
NSMutableDictionary *animationOptions = [NSMutableDictionary new];
// All changed index paths, sorted
NSMutableArray *allIndexPaths = [NSMutableArray new];
NSPredicate *indexPathInValidSection = [NSPredicate predicateWithBlock:^BOOL(NSIndexPath *indexPath, __unused NSDictionary *_) {
return ![sections containsIndex:indexPath.section];
}];
for (_ASHierarchyItemChange *change in changes) {
for (NSIndexPath *indexPath in change.indexPaths) {
if ([indexPathInValidSection evaluateWithObject:indexPath]) {
animationOptions[indexPath] = @(change.animationOptions);
[allIndexPaths addObject:indexPath];
}
}
}
SEL sorting = type == _ASHierarchyChangeTypeDelete ? @selector(asdk_inverseCompare:) : @selector(compare:);
[allIndexPaths sortUsingSelector:sorting];
// Create new changes by grouping sorted changes by animation option
NSMutableArray *result = [NSMutableArray new];
ASDataControllerAnimationOptions currentOptions = 0;
NSMutableArray *currentIndexPaths = [NSMutableArray array];
for (NSIndexPath *indexPath in allIndexPaths) {
ASDataControllerAnimationOptions options = [animationOptions[indexPath] integerValue];
// End the previous group if needed.
if (options != currentOptions && currentIndexPaths.count > 0) {
_ASHierarchyItemChange *change = [[_ASHierarchyItemChange alloc] initWithChangeType:type indexPaths:[currentIndexPaths copy] animationOptions:currentOptions presorted:YES];
[result addObject:change];
[currentIndexPaths removeAllObjects];
}
// Start a new group if needed.
if (currentIndexPaths.count == 0) {
currentOptions = options;
}
[currentIndexPaths addObject:indexPath];
}
// Finish up the last group.
if (currentIndexPaths.count > 0) {
_ASHierarchyItemChange *change = [[_ASHierarchyItemChange alloc] initWithChangeType:type indexPaths:[currentIndexPaths copy] animationOptions:currentOptions presorted:YES];
[result addObject:change];
}
[changes setArray:result];
}
@end