//
//  KBSkinDetailVC.m
//  keyBoard

#import "KBSkinDetailVC.h"
#import <Masonry/Masonry.h>
#import "UIColor+Extension.h"
#import "UICollectionViewLeftAlignedLayout.h"
#import "KBSkinDetailHeaderCell.h"
#import "KBSkinTagsContainerCell.h"
#import "KBSkinCardCell.h"
#import "KBSkinSectionTitleCell.h"
#import "KBSkinBottomActionView.h"
#import "KBShopVM.h"
#import "KBShopThemeTagModel.h"
#import "KBHUD.h"
#import "KBSkinService.h"

static NSString * const kHeaderCellId = @"kHeaderCellId";
static NSString * const kTagsContainerCellId = @"kTagsContainerCellId";
static NSString * const kSectionTitleCellId = @"kSectionTitleCellId";
static NSString * const kGridCellId = @"kGridCellId"; // 直接复用 KBSkinCardCell

typedef NS_ENUM(NSInteger, KBSkinDetailSection) {
    KBSkinDetailSectionHeader = 0,
    KBSkinDetailSectionTags,
    KBSkinDetailSectionTitle,
    KBSkinDetailSectionGrid,
    KBSkinDetailSectionCount
};

@interface KBSkinDetailVC () <UICollectionViewDataSource, UICollectionViewDelegateFlowLayout>
@property (nonatomic, strong) UICollectionView *collectionView; // 主列表
@property (nonatomic, strong) KBSkinBottomActionView *bottomBar; // 底部操作条
@property (nonatomic, copy) NSArray<NSString *> *tags;           // 标签数据
@property (nonatomic, copy) NSArray<NSDictionary *> *gridData;   // 底部网格数据
@property (nonatomic, strong) KBShopVM *shopVM;
@property (nonatomic, strong, nullable) KBShopThemeDetailModel *detailModel;
@property (nonatomic, assign) BOOL isProcessingAction;
@end

@implementation KBSkinDetailVC

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor whiteColor];

    self.tags = @[];
    self.gridData = @[
        @{ @"title": @"Dopamine" }, @{ @"title": @"Dopamine" },
        @{ @"title": @"Dopamine" }, @{ @"title": @"Dopamine" },
        @{ @"title": @"Dopamine" }, @{ @"title": @"Dopamine" },
    ];

    // 1. 列表
    [self.view addSubview:self.collectionView];

    // 2. 底部操作条（左右 15，高 45，可点击）
    [self.view addSubview:self.bottomBar];
    [self.bottomBar mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.equalTo(self.view).offset(15);
        make.right.equalTo(self.view).offset(-15);
        make.height.mas_equalTo([KBSkinBottomActionView preferredHeight]);
        make.bottom.equalTo(self.view.mas_safeAreaLayoutGuideBottom).offset(-10);
     
    }];

    // 列表底部距离操作条顶部 10
    [self.collectionView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.right.equalTo(self.view);
        make.top.equalTo(self.view).offset(KB_NAV_TOTAL_HEIGHT);
        make.bottom.equalTo(self.bottomBar.mas_top).offset(-10);
    }];

    [self updateBottomBarAppearance];
    [self fetchThemeDetailIfNeeded];
}

#pragma mark - UICollectionView DataSource

- (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView {
    return KBSkinDetailSectionCount;
}

- (NSInteger)collectionView:(UICollectionView *)collectionView numberOfItemsInSection:(NSInteger)section {
    switch (section) {
        case KBSkinDetailSectionHeader: return 1; // 顶部大卡片
        case KBSkinDetailSectionTags:   return self.tags.count > 0 ? 1 : 0;
        case KBSkinDetailSectionTitle:  return 1; // 标题
        case KBSkinDetailSectionGrid:   return self.gridData.count; // 2 列网格
    }
    return 0;
}

- (__kindof UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath {
    switch (indexPath.section) {
        case KBSkinDetailSectionHeader: {
            KBSkinDetailHeaderCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:kHeaderCellId forIndexPath:indexPath];
            [cell configWithDetail:self.detailModel];
            return cell;
        }
        case KBSkinDetailSectionTags: {
            KBSkinTagsContainerCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:kTagsContainerCellId forIndexPath:indexPath];
            [cell configWithTags:self.tags];
            return cell;
        }
        case KBSkinDetailSectionTitle: {
            KBSkinSectionTitleCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:kSectionTitleCellId forIndexPath:indexPath];
            [cell config:@"Recommended Skin"];
            return cell;
        }
        case KBSkinDetailSectionGrid: {
            KBSkinCardCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:kGridCellId forIndexPath:indexPath];
            NSDictionary *d = self.gridData[indexPath.item];
            [cell configWithTitle:d[@"title"] imageURL:nil price:@"20"];
            return cell;
        }
    }
    return [UICollectionViewCell new];
}

#pragma mark - UICollectionView DelegateFlowLayout

- (CGSize)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout sizeForItemAtIndexPath:(NSIndexPath *)indexPath {
    CGFloat W = collectionView.bounds.size.width;
    CGFloat insetLR = 16.0;
    CGFloat contentW = W - insetLR * 2;
    switch (indexPath.section) {
        case KBSkinDetailSectionHeader: {
            // 高度 = 图片 0.58W + 文案与上下留白（≈56）
            CGFloat h = KBFit(264) + 30;
            return CGSizeMake(contentW, h);
        }
        case KBSkinDetailSectionTags: {
            CGFloat h = [KBSkinTagsContainerCell heightForTags:self.tags width:W];
            return CGSizeMake(contentW, MAX(h, 0.1));
        }
        case KBSkinDetailSectionTitle: {
            return CGSizeMake(contentW, 44);
        }
        case KBSkinDetailSectionGrid: {
            // 2 列
            CGFloat spacing = 12.0;
            CGFloat itemW = floor((contentW - spacing) / 2.0);
//            CGFloat itemH = itemW * 0.75 + 56;
            return CGSizeMake(itemW, KBFit(197));
        }
    }
    return CGSizeZero;
}

- (UIEdgeInsets)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout insetForSectionAtIndex:(NSInteger)section {
    // 控制各区上下留白，缩小 Header 与 Tags 之间的间距
    switch (section) {
        case KBSkinDetailSectionHeader:
            // 顶部与导航之间 12，底部稍微缩小
            return UIEdgeInsetsMake(12, 16, 4, 16);
        case KBSkinDetailSectionTags:
            // 与 Header 更贴近一些
            return UIEdgeInsetsMake(14, 16, 5, 16);
        default:
            return UIEdgeInsetsMake(0, 16, 12, 16);
    }
}

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section {
    return 12.0;
}

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout *)collectionViewLayout minimumInteritemSpacingForSectionAtIndex:(NSInteger)section {
    // 网格区需要这个间距，其它区也保持统一
    return 12.0;
}

#pragma mark - Lazy

- (UICollectionView *)collectionView {
    if (!_collectionView) {
        UICollectionViewFlowLayout *layout = [UICollectionViewFlowLayout new];
        layout.scrollDirection = UICollectionViewScrollDirectionVertical;
        _collectionView = [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:layout];
        _collectionView.backgroundColor = [UIColor whiteColor];
        _collectionView.dataSource = self;
        _collectionView.delegate = self;

        // 注册 cell
        [_collectionView registerClass:KBSkinDetailHeaderCell.class forCellWithReuseIdentifier:kHeaderCellId];
        [_collectionView registerClass:KBSkinTagsContainerCell.class forCellWithReuseIdentifier:kTagsContainerCellId];
        [_collectionView registerClass:KBSkinSectionTitleCell.class forCellWithReuseIdentifier:kSectionTitleCellId];
        [_collectionView registerClass:KBSkinCardCell.class forCellWithReuseIdentifier:kGridCellId];
    }
    return _collectionView;
}

#pragma mark - Lazy (Bottom Bar)

- (KBSkinBottomActionView *)bottomBar {
    if (!_bottomBar) {
        _bottomBar = [[KBSkinBottomActionView alloc] init];
        // 中文注释：配置文案与图标，可根据业务传入金币图/价格
        [_bottomBar configWithTitle:@"Download" price:@"20" icon:nil];
        KBWeakSelf
        _bottomBar.tapHandler = ^{
            // 示例：点击下载/购买
//            [KBHUD showText:@"点击了下载"];
            // TODO: 在此处触发下载/购买逻辑
            [weakSelf handleDownloadAction];
        };
    }
    return _bottomBar;
}

#pragma mark - Actions
- (void)handleDownloadAction {
    if (self.isProcessingAction) { return; }
    if (self.themeId.length == 0) {
        [KBHUD showInfo:KBLocalized(@"主题信息缺失")];
        return;
    }
    if (!self.detailModel) {
        [KBHUD showInfo:KBLocalized(@"正在加载主题详情")];
        return;
    }
    if (self.detailModel.isPurchased) {
        [self requestDownload];
    } else {
        [self purchaseCurrentTheme];
    }
}

- (void)purchaseCurrentTheme {
    if (self.isProcessingAction) { return; }
    self.isProcessingAction = YES;
    [KBHUD show];
    __weak typeof(self) weakSelf = self;
    [self.shopVM purchaseThemeWithId:self.themeId completion:^(BOOL success, NSError * _Nullable error) {
        dispatch_async(dispatch_get_main_queue(), ^{
            weakSelf.isProcessingAction = NO;
            [KBHUD dismiss];
            if (error || !success) {
                NSString *msg = error.localizedDescription ?: KBLocalized(@"购买失败");
                [KBHUD showInfo:msg];
                return;
            }
            weakSelf.detailModel.isPurchased = YES;
            [weakSelf updateBottomBarAppearance];
            [weakSelf requestDownload];
        });
    }];
}

- (void)requestDownload {
    if (self.isProcessingAction) { return; }
    self.isProcessingAction = YES;
    [KBHUD show];
    NSMutableDictionary *skin = [NSMutableDictionary dictionary];
    if (!skin[@"id"] && self.detailModel.themeId) {
        skin[@"id"] = self.detailModel.themeId;
    }
    if (!skin[@"name"] && self.detailModel.themeName) {
        skin[@"name"] = self.detailModel.themeName;
    }
    if (!skin[@"themeDownloadUrl"]) {
        [KBHUD showInfo:KBLocalized(@"缺少下载地址")];
        return;
    }
    skin[@"themeDownloadUrl"] = self.detailModel.themeDownloadUrl;
    
    [[KBSkinService shared] applySkinWithJSON:skin
                           fromViewController:self
                                         mode:KBSkinSourceModeRemoteZip
                                    completion:^(BOOL success) {
        if (success) {
            [KBHUD showSuccess:KBLocalized(@"已开始下载")];
        } else {
            [KBHUD showInfo:KBLocalized(@"下载失败")];
        }
    }];
}

- (void)updateBottomBarAppearance {
    BOOL purchased = self.detailModel.isPurchased;
    if (purchased) {
        self.bottomBar.titleText = KBLocalized(@"Download again");
        self.bottomBar.showsPrice = NO;
    } else {
        NSString *price = self.detailModel ? [NSString stringWithFormat:@"%.2f", self.detailModel.themePrice] : @"0";
        self.bottomBar.titleText = KBLocalized(@"Download");
        self.bottomBar.priceText = price;
        self.bottomBar.showsPrice = YES;
        UIImage *coin = [UIImage imageNamed:@"shop_jb_icon"];
        if (coin) {
            self.bottomBar.iconImage = coin;
        }
    }
}

- (void)fetchThemeDetailIfNeeded {
    if (self.themeId.length == 0) {
        NSLog(@"[KBSkinDetailVC] themeId is empty, skip detail request");
        return;
    }
    __weak typeof(self) weakSelf = self;
    [self.shopVM fetchThemeDetailWithId:self.themeId completion:^(KBShopThemeDetailModel * _Nullable detail, NSError * _Nullable error) {
        dispatch_async(dispatch_get_main_queue(), ^{
            if (error) {
                NSLog(@"[KBSkinDetailVC] fetch detail failed: %@", error);
                return;
            }
            if (!detail) {
                NSLog(@"[KBSkinDetailVC] theme detail is empty");
                return;
            }
            weakSelf.detailModel = detail;
            NSMutableArray<NSString *> *tagNames = [NSMutableArray array];
            for (KBShopThemeTagModel *tag in detail.themeTag) {
                if (tag.label.length) {
                    [tagNames addObject:tag.label];
                }
            }
            weakSelf.tags = tagNames.copy;
            [weakSelf updateBottomBarAppearance];
            [weakSelf.collectionView reloadData];
        });
    }];
}

- (KBShopVM *)shopVM {
    if (!_shopVM) {
        _shopVM = [[KBShopVM alloc] init];
    }
    return _shopVM;
}

@end