//
//  KBEmojiDataProvider.m
//  CustomKeyboard
//

#import "KBEmojiDataProvider.h"
#import "KBLocalizationManager.h"
#import "KBConfig.h"

NSString * const KBEmojiRecentsDidChangeNotification = @"KBEmojiRecentsDidChangeNotification";

static NSString * const kKBEmojiJSONFileName = @"emoji_categories";
static NSString * const kKBEmojiRecentsStoreKey = @"KBEmojiRecentEmojis";
static NSString * const kKBEmojiRecentsCategoryId = @"recents";
static const NSUInteger kKBEmojiRecentsLimit = 32;

#pragma mark - Model Implementations

@interface KBEmojiItem ()
@property (nonatomic, copy, readwrite) NSString *value;
@property (nonatomic, copy, readwrite) NSString *name;
@end

@implementation KBEmojiItem

- (instancetype)initWithValue:(NSString *)value name:(NSString *)name {
    if (self = [super init]) {
        _value = [value copy];
        _name = [name copy];
    }
    return self;
}

- (id)copyWithZone:(NSZone *)zone {
    KBEmojiItem *item = [[[self class] allocWithZone:zone] initWithValue:self.value name:self.name];
    return item;
}

@end

@interface KBEmojiCategory ()
@property (nonatomic, copy, readwrite) NSString *identifier;
@property (nonatomic, copy) NSDictionary<NSString *, NSString *> *titleMap;
@property (nonatomic, copy, readwrite) NSString *displayTitle;
@property (nonatomic, copy, readwrite) NSString *iconSymbol;
@property (nonatomic, assign, readwrite, getter=isDynamic) BOOL dynamic;
@property (nonatomic, copy, readwrite) NSArray<KBEmojiItem *> *items;
@end

@implementation KBEmojiCategory

- (void)refreshDisplayTitleForLanguage:(NSString *)lang {
    if (lang.length == 0) {
        lang = KBLanguageCodeEnglish;
    }
    NSString *title = self.titleMap[lang];
    if (title.length == 0) {
        if ([lang.lowercaseString hasPrefix:@"zh"]) {
            title = self.titleMap[@"zh-Hans"] ?: self.titleMap[@"zh-hans"];
        }
    }
    if (title.length == 0) {
        title = self.titleMap[@"en"];
    }
    if (title.length == 0) {
        title = self.titleMap.allValues.firstObject;
    }
    self.displayTitle = title ?: @"";
}

@end

#pragma mark - Data Provider

@interface KBEmojiDataProvider ()
@property (nonatomic, copy) NSArray<KBEmojiCategory *> *categoriesInternal;
@property (nonatomic, strong) NSMutableDictionary<NSString *, KBEmojiItem *> *itemLookup;
@property (nonatomic, strong) NSMutableOrderedSet<NSString *> *recentValues;
@end

@implementation KBEmojiDataProvider

+ (instancetype)shared {
    static KBEmojiDataProvider *m;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        m = [KBEmojiDataProvider new];
        [[NSNotificationCenter defaultCenter] addObserver:m
                                                 selector:@selector(onLocalizationChanged:)
                                                     name:KBLocalizationDidChangeNotification
                                                   object:nil];
    });
    return m;
}

- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

- (NSArray<KBEmojiCategory *> *)categories {
    [self reloadIfNeeded];
    return self.categoriesInternal ?: @[];
}

- (void)reloadIfNeeded {
    if (self.categoriesInternal.count > 0) { return; }
    [self loadEmojiJSON];
    [self refreshLocalizedTitles];
    [self loadRecentsFromStore];
    [self rebuildRecentsCategory];
}

- (void)loadEmojiJSON {
    NSString *path = [[NSBundle mainBundle] pathForResource:kKBEmojiJSONFileName ofType:@"json"];
    if (path.length == 0) {
        return;
    }
    NSData *data = [NSData dataWithContentsOfFile:path];
    if (data.length == 0) { return; }

    NSError *err = nil;
    NSDictionary *root = [NSJSONSerialization JSONObjectWithData:data options:0 error:&err];
    if (!root || err) {
        NSLog(@"[Emoji] failed to parse json: %@", err);
        return;
    }
    NSArray *catArray = root[@"categories"];
    if (![catArray isKindOfClass:NSArray.class]) {
        return;
    }

    NSMutableArray<KBEmojiCategory *> *tmpCats = [NSMutableArray arrayWithCapacity:catArray.count];
    self.itemLookup = [NSMutableDictionary dictionary];

    for (NSDictionary *catDict in catArray) {
        if (![catDict isKindOfClass:NSDictionary.class]) continue;
        KBEmojiCategory *category = [KBEmojiCategory new];
        category.identifier = catDict[@"id"] ?: @"";
        NSDictionary *titleMap = catDict[@"title"];
        if ([titleMap isKindOfClass:NSDictionary.class]) {
            category.titleMap = titleMap;
        } else {
            category.titleMap = @{};
        }
        NSString *iconKey = catDict[@"icon"];
        category.iconSymbol = [self symbolForIconKey:iconKey];
        NSString *type = catDict[@"type"];
        category.dynamic = [type.lowercaseString isEqualToString:@"dynamic"];

        NSArray *emojiArray = catDict[@"emojis"];
        NSMutableArray<KBEmojiItem *> *items = [NSMutableArray arrayWithCapacity:[emojiArray count]];
        if ([emojiArray isKindOfClass:NSArray.class]) {
            for (NSDictionary *emojiDict in emojiArray) {
                if (![emojiDict isKindOfClass:NSDictionary.class]) continue;
                NSString *value = emojiDict[@"value"];
                if (value.length == 0) continue;
                NSString *name = emojiDict[@"name"] ?: @"";
                KBEmojiItem *item = [[KBEmojiItem alloc] initWithValue:value name:name];
                [items addObject:item];
                if (value.length > 0) {
                    self.itemLookup[value] = item;
                }
            }
        }
        category.items = items.copy;
        [tmpCats addObject:category];
    }
    self.categoriesInternal = tmpCats.copy;
}

- (NSString *)symbolForIconKey:(NSString *)key {
    static NSDictionary<NSString *, NSString *> *map;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        map = @{
            @"emoji_tab_recent": @"🕘",
            @"emoji_tab_people": @"😊",
            @"emoji_tab_nature": @"🌿",
            @"emoji_tab_food": @"🍔",
            @"emoji_tab_activity": @"🏀",
            @"emoji_tab_travel": @"✈️",
            @"emoji_tab_objects": @"💡",
            @"emoji_tab_symbols": @"♾",
            @"emoji_tab_flags": @"🏳️"
        };
    });
    NSString *symbol = map[key];
    return symbol.length ? symbol : @"●";
}

- (void)refreshLocalizedTitles {
    NSString *lang = [KBLocalizationManager shared].currentLanguageCode ?: KBLanguageCodeEnglish;
    for (KBEmojiCategory *cat in self.categoriesInternal) {
        [cat refreshDisplayTitleForLanguage:lang];
    }
}

- (void)onLocalizationChanged:(__unused NSNotification *)note {
    [self refreshLocalizedTitles];
    [[NSNotificationCenter defaultCenter] postNotificationName:KBEmojiRecentsDidChangeNotification object:nil];
}

- (void)recordEmojiSelection:(NSString *)emoji {
    if (emoji.length == 0) return;
    [self reloadIfNeeded];
    if (!self.recentValues) {
        self.recentValues = [NSMutableOrderedSet orderedSet];
    }
    [self.recentValues removeObject:emoji];
    [self.recentValues insertObject:emoji atIndex:0];
    while (self.recentValues.count > kKBEmojiRecentsLimit) {
        [self.recentValues removeObjectAtIndex:self.recentValues.count - 1];
    }
    [self saveRecentsToStore];
    [self rebuildRecentsCategory];
    [[NSNotificationCenter defaultCenter] postNotificationName:KBEmojiRecentsDidChangeNotification object:nil];
}

- (void)loadRecentsFromStore {
    NSUserDefaults *defs = [[NSUserDefaults alloc] initWithSuiteName:AppGroup];
    if (!defs) { defs = NSUserDefaults.standardUserDefaults; }
    NSArray *stored = [defs objectForKey:kKBEmojiRecentsStoreKey];
    NSMutableOrderedSet *set = [NSMutableOrderedSet orderedSet];
    if ([stored isKindOfClass:NSArray.class]) {
        for (id obj in stored) {
            if (![obj isKindOfClass:NSString.class]) continue;
            NSString *str = (NSString *)obj;
            if (str.length == 0) continue;
            [set addObject:str];
            if (set.count >= kKBEmojiRecentsLimit) break;
        }
    }
    self.recentValues = set;
}

- (void)saveRecentsToStore {
    if (!self.recentValues) return;
    NSArray *arr = self.recentValues.array;
    NSUserDefaults *defs = [[NSUserDefaults alloc] initWithSuiteName:AppGroup];
    if (!defs) { defs = NSUserDefaults.standardUserDefaults; }
    [defs setObject:arr forKey:kKBEmojiRecentsStoreKey];
    [defs synchronize];
}

- (void)rebuildRecentsCategory {
    KBEmojiCategory *recent = [self categoryForIdentifier:kKBEmojiRecentsCategoryId];
    if (!recent) return;
    NSArray<NSString *> *values = self.recentValues.array ?: @[];
    NSMutableArray<KBEmojiItem *> *items = [NSMutableArray arrayWithCapacity:values.count];
    for (NSString *value in values) {
        KBEmojiItem *item = self.itemLookup[value];
        if (!item) {
            item = [[KBEmojiItem alloc] initWithValue:value name:@""];
        }
        [items addObject:item];
    }
    recent.items = items.copy;
}

- (KBEmojiCategory *)categoryForIdentifier:(NSString *)identifier {
    if (identifier.length == 0) return nil;
    for (KBEmojiCategory *cat in self.categoriesInternal) {
        if ([cat.identifier isEqualToString:identifier]) {
            return cat;
        }
    }
    return nil;
}

@end