//
//  XJHealthKnowledgeManager.m
//  XinjiangProject
//
//  Created by Apple on 2026/6/29.
//

#import "XJHealthKnowledgeManager.h"
#import <CommonCrypto/CommonHMAC.h>

#pragma mark - ————— Manager —————

@interface XJHealthKnowledgeManager ()

@property (nonatomic, copy) NSString * cachedToken;

@end

@implementation XJHealthKnowledgeManager

+ (instancetype)sharedManager {
    static XJHealthKnowledgeManager * instance = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        instance = [[XJHealthKnowledgeManager alloc] init];
    });
    return instance;
}

#pragma mark - ————— HMAC-SHA256 —————

- (void)clearToken {
    self.cachedToken = nil;
    DLog(@"[健康知识] Token 已清除");
}

+ (NSString *)hmacSHA256:(NSString *)data key:(NSString *)key {
    const char * cKey  = [key cStringUsingEncoding:NSUTF8StringEncoding];
    const char * cData = [data cStringUsingEncoding:NSUTF8StringEncoding];
    unsigned char result[CC_SHA256_DIGEST_LENGTH];
    CCHmac(kCCHmacAlgSHA256, cKey, strlen(cKey), cData, strlen(cData), result);

    NSMutableString * hash = [[NSMutableString alloc] initWithCapacity:CC_SHA256_DIGEST_LENGTH * 2];
    for (int i = 0; i < CC_SHA256_DIGEST_LENGTH; i++) {
        [hash appendFormat:@"%02x", result[i]];
    }
    return hash;
}

#pragma mark - ————— 获取 Token —————

- (void)getTokenWithUserId:(NSString *)userId
                    workNo:(NSString *)workNo
                   success:(void (^)(NSString *))success
                   failure:(void (^)(NSString *))failure {

    NSString * urlString = [NSString stringWithFormat:@"%@%@", kHealthKnowledgeBaseURL, kHealthKnowledgeTokenPath];

    // 构建请求体
    NSDictionary * bodyDict = @{ @"userId": userId ?: @"",
                                 @"workNo": workNo ?: @"" };
    NSData * bodyData = [NSJSONSerialization dataWithJSONObject:bodyDict options:0 error:nil];
    NSString * bodyString = [[NSString alloc] initWithData:bodyData encoding:NSUTF8StringEncoding];

    // 签名
    NSString * timestamp = [NSString stringWithFormat:@"%.0f", [[NSDate date] timeIntervalSince1970]];
    NSString * stringToSign = [NSString stringWithFormat:@"%@%@", timestamp, bodyString];
    NSString * sign = [[self class] hmacSHA256:stringToSign key:kHealthKnowledgeSecretKey];

    NSMutableURLRequest * request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:urlString]];
    request.HTTPMethod = @"POST";
    [request setValue:@"application/json; charset=utf-8" forHTTPHeaderField:@"Content-Type"];
    [request setValue:timestamp forHTTPHeaderField:@"X-Timestamp"];
    [request setValue:sign forHTTPHeaderField:@"X-Sign"];
    request.HTTPBody = bodyData;

    DLog(@"[健康知识] 请求 Token URL: %@", urlString);
    DLog(@"[健康知识] 签名串: %@", stringToSign);
    DLog(@"[健康知识] X-Sign: %@", sign);

    [self sendRequest:request completion:^(NSDictionary * json) {
        DLog(@"[健康知识] Token 响应: %@", json);
        if ([json[@"code"] integerValue] == 200) {
            NSString * token = json[@"data"][@"token"];
            if (!ValidStr(token)) {
                self.cachedToken = token;
                DLog(@"[健康知识] Token 获取成功: %@", token);
                if (success) success(token);
            } else {
                DLog(@"[健康知识] Token 为空");
                if (failure) failure(@"token 为空");
            }
        } else {
            DLog(@"[健康知识] Token 失败: %@", json[@"msg"]);
            if (failure) failure(json[@"msg"] ?: @"获取 token 失败");
        }
    } failure:^(NSString * errorMsg) {
        DLog(@"[健康知识] Token 请求异常: %@", errorMsg);
        if (failure) failure(errorMsg);
    }];
}

#pragma mark - ————— 栏目列表 —————

- (void)getCategoryListWithToken:(NSString *)token
                         success:(void (^)(NSArray<XJHealthCategoryModel *> *))success
                         failure:(void (^)(NSString *))failure {

    NSString * urlString = [NSString stringWithFormat:@"%@%@", kHealthKnowledgeBaseURL, kHealthKnowledgeCategoryPath];

    NSMutableURLRequest * request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:urlString]];
    request.HTTPMethod = @"GET";
    [request setValue:token forHTTPHeaderField:@"token"];

    [self sendRequest:request completion:^(NSDictionary * json) {
        if ([json[@"code"] integerValue] == 200) {
            NSArray * dataArray = json[@"data"];
            NSMutableArray * categories = [[NSMutableArray alloc] init];
            if ([dataArray isKindOfClass:[NSArray class]]) {
                for (NSDictionary * dict in dataArray) {
                    XJHealthCategoryModel * m = [XJHealthCategoryModel modelWithDictionary:dict];
                    [categories addObject:m];
                }
            }
            if (success) success(categories);
        } else {
            if (failure) failure(json[@"msg"] ?: @"获取栏目列表失败");
        }
    } failure:^(NSString * errorMsg) {
        if (failure) failure(errorMsg);
    }];
}

#pragma mark - ————— 分页查询文章 —————

- (void)getArticleListWithToken:(NSString *)token
                     categoryId:(NSInteger)categoryId
                    articleType:(NSString *)articleType
                        pageNum:(NSInteger)pageNum
                       pageSize:(NSInteger)pageSize
                        success:(void (^)(NSArray<XJHealthArticleModel *> *, NSInteger))success
                        failure:(void (^)(NSString *))failure {

    NSMutableString * urlString = [NSMutableString stringWithFormat:@"%@%@", kHealthKnowledgeBaseURL, kHealthKnowledgeArticleListPath];
    [urlString appendFormat:@"?categoryId=%ld&pageNum=%ld&pageSize=%ld&showAppHomepage=Y",
     (long)categoryId, (long)pageNum, (long)pageSize];

    if (!ValidStr(articleType)) {
        [urlString appendFormat:@"&articleType=%@", articleType];
    }

    NSMutableURLRequest * request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:urlString]];
    request.HTTPMethod = @"GET";
    [request setValue:token forHTTPHeaderField:@"token"];

    [self sendRequest:request completion:^(NSDictionary * json) {
        if ([json[@"code"] integerValue] == 200) {
            NSArray * rows = json[@"rows"];
            NSInteger total = [json[@"total"] integerValue];
            NSMutableArray * articles = [[NSMutableArray alloc] init];
            if ([rows isKindOfClass:[NSArray class]]) {
                for (NSDictionary * dict in rows) {
                    XJHealthArticleModel * m = [XJHealthArticleModel modelWithDictionary:dict];
                    [articles addObject:m];
                }
            }
            if (success) success(articles, total);
        } else {
            if (failure) failure(json[@"msg"] ?: @"获取文章列表失败");
        }
    } failure:^(NSString * errorMsg) {
        if (failure) failure(errorMsg);
    }];
}

#pragma mark - ————— 通用请求 —————

- (void)sendRequest:(NSURLRequest *)request
         completion:(void (^)(NSDictionary * json))completion
            failure:(void (^)(NSString * errorMsg))failure {

    DLog(@"[健康知识] >>> 请求: %@ %@", request.HTTPMethod, request.URL.absoluteString);

    NSURLSession * session = [NSURLSession sharedSession];
    NSURLSessionDataTask * task = [session dataTaskWithRequest:request
                                             completionHandler:^(NSData * _Nullable data,
                                                                 NSURLResponse * _Nullable response,
                                                                 NSError * _Nullable error) {
        dispatch_async(dispatch_get_main_queue(), ^{
            if (error) {
                DLog(@"[健康知识] <<< 网络错误: %@", error.localizedDescription);
                if (failure) failure(error.localizedDescription);
                return;
            }

            NSHTTPURLResponse * httpResp = (NSHTTPURLResponse *)response;
            NSInteger statusCode = httpResp.statusCode;
            DLog(@"[健康知识] <<< HTTP %ld", (long)statusCode);

            if (statusCode != 200) {
                NSString * msg = [NSString stringWithFormat:@"HTTP %ld", (long)statusCode];
                DLog(@"[健康知识] <<< 请求失败: %@", msg);
                if (failure) failure(msg);
                return;
            }

            NSError * jsonError = nil;
            NSDictionary * json = [NSJSONSerialization JSONObjectWithData:data options:0 error:&jsonError];
            if (jsonError || ![json isKindOfClass:[NSDictionary class]]) {
                DLog(@"[健康知识] <<< JSON 解析失败");
                if (failure) failure(@"数据解析失败");
                return;
            }

            DLog(@"[健康知识] <<< 响应: %@", json);
            if (completion) completion(json);
        });
    }];
    [task resume];
}

@end