//
//  KBNetworkManager.m
//  CustomKeyboard
//

#import "KBNetworkManager.h"
#import "AFNetworking.h"
#import "KBAuthManager.h"
//#import "KBUserSessionManager.h"
#import "KBSignUtils.h"
NSErrorDomain const KBNetworkErrorDomain = @"com.company.keyboard.network";

@interface KBNetworkManager ()
@property (nonatomic, strong) AFHTTPSessionManager *manager; // AFN 管理器（ephemeral 配置）
// 私有错误派发
- (void)fail:(KBNetworkError)code completion:(KBNetworkCompletion)completion;
@end

@implementation KBNetworkManager

+ (instancetype)shared {
    static KBNetworkManager *m; static dispatch_once_t onceToken; dispatch_once(&onceToken, ^{ m = [KBNetworkManager new]; });
    return m;
}

- (instancetype)init {
    if (self = [super init]) {
        _enabled = NO; // 键盘扩展默认无网络能力，需外部显式开启
        _timeout = 10.0;
        // 默认请求头：Accept 任意类型 + 使用项目多语言管理器设置 Accept-Language
        NSString *lang = [KBLocalizationManager shared].currentLanguageCode ?: KBLanguageCodeEnglish;
//        NSString *token = [KBUserSessionManager shared].accessToken ? [KBUserSessionManager shared].accessToken : @"";
        _defaultHeaders = @{
            @"Accept": @"*/*",
            @"Accept-Language": lang
        };
        // 设置基础域名，路径可相对该地址拼接
        _baseURL = [NSURL URLWithString:KB_BASE_URL];
    }
    return self;
}

- (void)getSignWithParare:(NSDictionary *)bodyParams{
   
    NSString *appId    = @"loveKeyboard";
    NSString *secret   = @"kZJM39HYvhxwbJkG1fmquQRVkQiLAh2H"; // 和服务端保持一致
    NSString *timestamp = [KBSignUtils currentTimestamp];
    NSString *nonce     = [KBSignUtils generateNonceWithLength:16];
    // 1. 组装参与签名的所有参数
    NSMutableDictionary<NSString *, NSString *> *signParams = [NSMutableDictionary dictionary];
    signParams[@"appId"]     = appId;
    signParams[@"timestamp"] = timestamp;
    signParams[@"nonce"]     = nonce;
    // 把 body 里的字段也加入签名参数
    [bodyParams enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
        if ([obj isKindOfClass:[NSString class]]) {
            signParams[key] = obj;
        } else {
            signParams[key] = [obj description];
        }
    }];
    NSString *sign = [KBSignUtils signWithParams:signParams secret:secret];

    // 将签名相关字段合并进默认请求头
    NSMutableDictionary<NSString *, NSString *> *headers =
    [self.defaultHeaders mutableCopy] ?: [NSMutableDictionary dictionary];

    if (sign.length > 0) {
        headers[@"X-Sign"] = sign;
    }
    headers[@"X-App-Id"]    = appId;
    headers[@"X-Timestamp"] = timestamp;
    headers[@"X-Nonce"]     = nonce;

    // 触发 copy 语义，确保对外仍是不可变字典
    self.defaultHeaders = headers;
}

#pragma mark - Public

- (NSURLSessionDataTask *)GET:(NSString *)path
                     parameters:(NSDictionary *)parameters
                        headers:(NSDictionary<NSString *,NSString *> *)headers
                      completion:(KBNetworkCompletion)completion {
    [self getSignWithParare:parameters];
    if (![self ensureEnabled:completion]) return nil;
    NSString *urlString = [self buildURLStringWithPath:path];
    if (!urlString) { [self fail:KBNetworkErrorInvalidURL completion:completion]; return nil; }
    // 使用 AFHTTPRequestSerializer 生成带参数与头的请求
    AFHTTPRequestSerializer *serializer = [AFHTTPRequestSerializer serializer];
    serializer.timeoutInterval = self.timeout;
    NSError *serror = nil;
    NSMutableURLRequest *req = [serializer requestWithMethod:@"GET"
                                                   URLString:urlString
                                                  parameters:parameters
                                                       error:&serror];
    if (serror || !req) {
        if (completion) completion(nil, nil, serror ?: [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorInvalidURL userInfo:@{NSLocalizedDescriptionKey: KBLocalized(@"Invalid URL")}]);
        return nil;
    }
    [self applyHeaders:headers toMutableRequest:req contentType:nil];
    return [self startAFJSONTaskWithRequest:req completion:completion];
}

- (NSURLSessionDataTask *)POST:(NSString *)path
                       jsonBody:(id)jsonBody
                        headers:(NSDictionary<NSString *,NSString *> *)headers
                      completion:(KBNetworkCompletion)completion {
    [self getSignWithParare:jsonBody];

    if (![self ensureEnabled:completion]) return nil;
    NSString *urlString = [self buildURLStringWithPath:path];
    if (!urlString) { [self fail:KBNetworkErrorInvalidURL completion:completion]; return nil; }
    // 用 JSON 序列化器生成 JSON Body 的请求
    AFJSONRequestSerializer *serializer = [AFJSONRequestSerializer serializer];
    serializer.timeoutInterval = self.timeout;
    NSError *error = nil;
    NSMutableURLRequest *req = [serializer requestWithMethod:@"POST"
                                                   URLString:urlString
                                                  parameters:jsonBody
                                                       error:&error];
    if (error) { if (completion) completion(nil, nil, error); return nil; }
    [self applyHeaders:headers toMutableRequest:req contentType:nil];
    return [self startAFJSONTaskWithRequest:req completion:completion];
}

- (NSURLSessionDataTask *)GETData:(NSString *)path
                       parameters:(NSDictionary *)parameters
                          headers:(NSDictionary<NSString *,NSString *> *)headers
                        completion:(KBNetworkDataCompletion)completion {
    [self getSignWithParare:parameters];
    if (!self.isEnabled) {
        NSError *e = [NSError errorWithDomain:KBNetworkErrorDomain
                                         code:KBNetworkErrorDisabled
                                     userInfo:@{NSLocalizedDescriptionKey: KBLocalized(@"Network disabled (Full Access may be off)")}];
        if (completion) completion(nil, nil, e);
        return nil;
    }
    NSString *urlString = [self buildURLStringWithPath:path];
    if (!urlString) {
        NSError *e = [NSError errorWithDomain:KBNetworkErrorDomain
                                         code:KBNetworkErrorInvalidURL
                                     userInfo:@{NSLocalizedDescriptionKey: KBLocalized(@"Invalid URL")}];
        if (completion) completion(nil, nil, e);
        return nil;
    }
    AFHTTPRequestSerializer *serializer = [AFHTTPRequestSerializer serializer];
    serializer.timeoutInterval = self.timeout;
    NSError *serror = nil;
    NSMutableURLRequest *req = [serializer requestWithMethod:@"GET"
                                                   URLString:urlString
                                                  parameters:parameters
                                                       error:&serror];
    if (serror || !req) {
        if (completion) completion(nil, nil, serror ?: [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorInvalidURL userInfo:@{NSLocalizedDescriptionKey: KBLocalized(@"Invalid URL")}]);
        return nil;
    }
    [self applyHeaders:headers toMutableRequest:req contentType:nil];
    return [self startAFDataTaskWithRequest:req completion:completion];
}

#pragma mark - Core

- (BOOL)ensureEnabled:(KBNetworkCompletion)completion {
    if (!self.isEnabled) {
        NSError *e = [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorDisabled userInfo:@{NSLocalizedDescriptionKey: KBLocalized(@"Network disabled (Full Access may be off)")}];
        if (completion) completion(nil, nil, e);
        return NO;
    }
    return YES;
}

- (NSString *)buildURLStringWithPath:(NSString *)path {
    if (path.length == 0) return nil;
    if ([path hasPrefix:@"http://"] || [path hasPrefix:@"https://"]) {
        return path;
    }
    if (self.baseURL) {
        // 统一为目录型 base（以 / 结尾），并剥掉 path 的前导 /，避免覆盖 base 路径
        NSString *base = self.baseURL.absoluteString ?: @"";
        if (![base hasSuffix:@"/"]) { base = [base stringByAppendingString:@"/"]; }
        NSURL *dirBase = [NSURL URLWithString:base];
        NSString *relative = ([path hasPrefix:@"/"]) ? [path substringFromIndex:1] : path;
        return [NSURL URLWithString:relative relativeToURL:dirBase].absoluteURL.absoluteString;
    }
    return path; // 当无 baseURL 且 path 不是完整 URL 时，让 AFN 处理（可能失败）
}

- (void)applyHeaders:(NSDictionary<NSString *,NSString *> *)headers toMutableRequest:(NSMutableURLRequest *)req contentType:(NSString *)contentType {
    // 合并默认头与局部头，并注入授权头（若可用）。局部覆盖优先。
    NSMutableDictionary *all = [self.defaultHeaders mutableCopy] ?: [NSMutableDictionary new];
    NSString *token = [KBAuthManager shared].current.accessToken;
    if (token.length > 0) {
        all[@"auth-token"] = token;
    } else {
        [all removeObjectForKey:@"auth-token"];
    }
    NSDictionary *auth = [[KBAuthManager shared] authorizationHeader];
    [auth enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) { all[key] = obj; }];
    if (contentType) all[@"Content-Type"] = contentType;
    [headers enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) { all[key] = obj; }];
    [all enumerateKeysAndObjectsUsingBlock:^(NSString *key, NSString *obj, BOOL *stop) { [req setValue:obj forHTTPHeaderField:key]; }];
}

- (NSURLSessionDataTask *)startAFJSONTaskWithRequest:(NSURLRequest *)req completion:(KBNetworkCompletion)completion {
    // 响应先用原始数据返回，再按 Content-Type 解析 JSON（与原实现一致）
    self.manager.responseSerializer = [AFHTTPResponseSerializer serializer];
    NSURLSessionDataTask *task = [self.manager dataTaskWithRequest:req uploadProgress:nil downloadProgress:nil completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
        // AFN 默认对非 2xx 的状态码返回 error；这里直接回调上层
        if (error) {
            if (completion) completion(nil, response, error);
            return;
        }
        NSData *data = (NSData *)responseObject;
        if (![data isKindOfClass:[NSData class]]) {
            if (completion) completion(nil, response, [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorInvalidResponse userInfo:@{NSLocalizedDescriptionKey:KBLocalized(@"No data")}]);
            return;
        }
        NSString *ct = nil;
        if ([response isKindOfClass:[NSHTTPURLResponse class]]) {
            ct = ((NSHTTPURLResponse *)response).allHeaderFields[@"Content-Type"];
        }
        // 更宽松的 JSON 判定：Content-Type 里包含 json；或首字符是 { / [
        BOOL looksJSON = (ct && [[ct lowercaseString] containsString:@"json"]);
        if (!looksJSON) {
            // 内容嗅探（不依赖服务端声明）
            const unsigned char *bytes = data.bytes;
            NSUInteger len = data.length;
            for (NSUInteger i = 0; !looksJSON && i < len; i++) {
                unsigned char c = bytes[i];
                if (c == ' ' || c == '\n' || c == '\r' || c == '\t') continue;
                looksJSON = (c == '{' || c == '[');
                break;
            }
        }
        if (looksJSON) {
            NSError *jsonErr = nil;
            id json = [NSJSONSerialization JSONObjectWithData:data options:0 error:&jsonErr];
            if (jsonErr) {
                if (completion) completion(nil, response, [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorDecodeFailed userInfo:@{NSLocalizedDescriptionKey:KBLocalized(@"Failed to parse JSON")}]);
                return;
            }
            if (![json isKindOfClass:[NSDictionary class]]) {
                if (completion) completion(nil, response, [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorInvalidResponse userInfo:@{NSLocalizedDescriptionKey:KBLocalized(@"Invalid response")}]);
                return;
            }
            if (completion) completion((NSDictionary *)json, response, nil);
        } else {
            if (completion) completion(nil, response, [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorInvalidResponse userInfo:@{NSLocalizedDescriptionKey:KBLocalized(@"Invalid response")}]);
        }
    }];
    [task resume];
    return task;
}

- (NSURLSessionDataTask *)startAFDataTaskWithRequest:(NSURLRequest *)req completion:(KBNetworkDataCompletion)completion {
    self.manager.responseSerializer = [AFHTTPResponseSerializer serializer];
    NSURLSessionDataTask *task = [self.manager dataTaskWithRequest:req uploadProgress:nil downloadProgress:nil completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
        if (error) {
            if (completion) completion(nil, response, error);
            return;
        }
        NSData *data = (NSData *)responseObject;
        if (![data isKindOfClass:[NSData class]]) {
            if (completion) completion(nil, response, [NSError errorWithDomain:KBNetworkErrorDomain code:KBNetworkErrorInvalidResponse userInfo:@{NSLocalizedDescriptionKey:KBLocalized(@"No data")}]);
            return;
        }
        if (completion) completion(data, response, nil);
    }];
    [task resume];
    return task;
}

#pragma mark - AFHTTPSessionManager

- (AFHTTPSessionManager *)manager {
    if (!_manager) {
        NSURLSessionConfiguration *cfg = [NSURLSessionConfiguration ephemeralSessionConfiguration];
        cfg.requestCachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
        // 不在会话级别设置超时，避免与 per-request 的 serializer.timeoutInterval 产生不一致
        if (@available(iOS 11.0, *)) { cfg.waitsForConnectivity = YES; }
        _manager = [[AFHTTPSessionManager alloc] initWithBaseURL:nil sessionConfiguration:cfg];
        // 默认不使用 JSON 解析器，保持原生数据，再按需解析
        _manager.responseSerializer = [AFHTTPResponseSerializer serializer];
    }
    return _manager;
}

#pragma mark - Private helpers

- (void)fail:(KBNetworkError)code completion:(KBNetworkCompletion)completion {
    NSString *msg = KBLocalized(@"Network error");
    switch (code) {
        case KBNetworkErrorDisabled: msg = KBLocalized(@"Network disabled (Full Access may be off)"); break;
        case KBNetworkErrorInvalidURL: msg = KBLocalized(@"Invalid URL"); break;
        case KBNetworkErrorInvalidResponse: msg = KBLocalized(@"Invalid response"); break;
        case KBNetworkErrorDecodeFailed: msg = KBLocalized(@"Parse failed"); break;
        default: break;
    }
    NSError *e = [NSError errorWithDomain:KBNetworkErrorDomain
                                     code:code
                                 userInfo:@{NSLocalizedDescriptionKey: msg}];
    if (completion) completion(nil, nil, e);
}

@end