Updated packages, rewrote player = gapless playback, faster loading

just_audio/ios/Classes/ConcatenatingAudioSource.m

@@ -0,0 +1,109 @@
+#import "AudioSource.h"
+#import "ConcatenatingAudioSource.h"
+#import <AVFoundation/AVFoundation.h>
+#import <stdlib.h>
+
+@implementation ConcatenatingAudioSource {
+    NSMutableArray<AudioSource *> *_audioSources;
+    NSMutableArray<NSNumber *> *_shuffleOrder;
+}
+
+- (instancetype)initWithId:(NSString *)sid audioSources:(NSMutableArray<AudioSource *> *)audioSources {
+    self = [super initWithId:sid];
+    NSAssert(self, @"super init cannot be nil");
+    _audioSources = audioSources;
+    return self;
+}
+
+- (int)count {
+    return _audioSources.count;
+}
+
+- (void)insertSource:(AudioSource *)audioSource atIndex:(int)index {
+    [_audioSources insertObject:audioSource atIndex:index];
+}
+
+- (void)removeSourcesFromIndex:(int)start toIndex:(int)end {
+    if (end == -1) end = _audioSources.count;
+    for (int i = start; i < end; i++) {
+        [_audioSources removeObjectAtIndex:start];
+    }
+}
+
+- (void)moveSourceFromIndex:(int)currentIndex toIndex:(int)newIndex {
+    AudioSource *source = _audioSources[currentIndex];
+    [_audioSources removeObjectAtIndex:currentIndex];
+    [_audioSources insertObject:source atIndex:newIndex];
+}
+
+- (int)buildSequence:(NSMutableArray *)sequence treeIndex:(int)treeIndex {
+    for (int i = 0; i < [_audioSources count]; i++) {
+        treeIndex = [_audioSources[i] buildSequence:sequence treeIndex:treeIndex];
+    }
+    return treeIndex;
+}
+
+- (void)findById:(NSString *)sourceId matches:(NSMutableArray<AudioSource *> *)matches {
+    [super findById:sourceId matches:matches];
+    for (int i = 0; i < [_audioSources count]; i++) {
+        [_audioSources[i] findById:sourceId matches:matches];
+    }
+}
+
+- (NSArray *)getShuffleOrder {
+    NSMutableArray *order = [NSMutableArray new];
+    int offset = [order count];
+    NSMutableArray *childOrders = [NSMutableArray new]; // array of array of ints
+    for (int i = 0; i < [_audioSources count]; i++) {
+        AudioSource *audioSource = _audioSources[i];
+        NSArray *childShuffleOrder = [audioSource getShuffleOrder];
+        NSMutableArray *offsetChildShuffleOrder = [NSMutableArray new];
+        for (int j = 0; j < [childShuffleOrder count]; j++) {
+            [offsetChildShuffleOrder addObject:@([childShuffleOrder[j] integerValue] + offset)];
+        }
+        [childOrders addObject:offsetChildShuffleOrder];
+        offset += [childShuffleOrder count];
+    }
+    for (int i = 0; i < [_audioSources count]; i++) {
+        [order addObjectsFromArray:childOrders[[_shuffleOrder[i] integerValue]]];
+    }
+    return order;
+}
+
+- (int)shuffle:(int)treeIndex currentIndex:(int)currentIndex {
+    int currentChildIndex = -1;
+    for (int i = 0; i < [_audioSources count]; i++) {
+        int indexBefore = treeIndex;
+        AudioSource *child = _audioSources[i];
+        treeIndex = [child shuffle:treeIndex currentIndex:currentIndex];
+        if (currentIndex >= indexBefore && currentIndex < treeIndex) {
+            currentChildIndex = i;
+        } else {}
+    }
+    // Shuffle so that the current child is first in the shuffle order
+    _shuffleOrder = [NSMutableArray arrayWithCapacity:[_audioSources count]];
+    for (int i = 0; i < [_audioSources count]; i++) {
+        [_shuffleOrder addObject:@(0)];
+    }
+    NSLog(@"shuffle: audioSources.count=%d and shuffleOrder.count=%d", [_audioSources count], [_shuffleOrder count]);
+    // First generate a random shuffle
+    for (int i = 0; i < [_audioSources count]; i++) {
+        int j = arc4random_uniform(i + 1);
+        _shuffleOrder[i] = _shuffleOrder[j];
+        _shuffleOrder[j] = @(i);
+    }
+    // Then bring currentIndex to the front
+    if (currentChildIndex != -1) {
+      for (int i = 1; i < [_audioSources count]; i++) {
+        if ([_shuffleOrder[i] integerValue] == currentChildIndex) {
+          NSNumber *v = _shuffleOrder[0];
+          _shuffleOrder[0] = _shuffleOrder[i];
+          _shuffleOrder[i] = v;
+          break;
+        }
+      }
+    }
+    return treeIndex;
+}
+
+@end