//
//  MOLeftAlignedFlowLayout.m
//  MiMoLive
//
//  Created by MiMo on 2025/7/8.
//

#import "MOLeftAlignedFlowLayout.h"

@implementation MOLeftAlignedFlowLayout

- (NSArray<UICollectionViewLayoutAttributes *> *)layoutAttributesForElementsInRect:(CGRect)rect {
    NSArray *attributes = [super layoutAttributesForElementsInRect:rect];
    NSMutableArray *updatedAttributes = [NSMutableArray array];
    
    // 当前行的 left 起点
    CGFloat leftMargin = self.sectionInset.left;
    CGFloat maxY = -1.0;

    for (UICollectionViewLayoutAttributes *attr in attributes) {
        // 只处理 cell，跳过 header/footer
        if (attr.representedElementCategory == UICollectionElementCategoryCell) {
            // 如果是新的一行
            if (attr.frame.origin.y >= maxY) {
                leftMargin = self.sectionInset.left;
            }

            CGRect frame = attr.frame;
            frame.origin.x = leftMargin;
            attr.frame = frame;

            leftMargin += frame.size.width + self.minimumInteritemSpacing;
            maxY = MAX(CGRectGetMaxY(frame), maxY);
        }

        [updatedAttributes addObject:attr];
    }
    
    return updatedAttributes;
}

@end