//
//  AVVideoConfiguration.m
//  AVDemo
//

#import "AVVideoConfiguration.h"

@implementation AVVideoConfiguration

#pragma mark - Initialization

- (instancetype)init {
    if (self = [super init]) {
        // 初始化默认值
        _nickname = @"";
        _streamId = @"";
        _codec = AVVideoCodeH264;
    }
    return self;
}

#pragma mark - Factory Methods

+ (instancetype)defaultConfiguration {
    AVVideoConfiguration *config = [[AVVideoConfiguration alloc] init];
    
    // 生成随机昵称
    NSInteger randomNum = arc4random_uniform(1000);
    config.nickname = [NSString stringWithFormat:@"test%03ld", (long)randomNum];
    
    // 生成随机 streamId：stream + 3位随机数字
    NSInteger streamRandomNum = 100 + arc4random_uniform(900); // 100-999
    config.streamId = [NSString stringWithFormat:@"%ld", (long)streamRandomNum];
    
    config.codec = AVVideoCodeH264;
    
    // 设置默认分辨率为 720p
    [config setResolution:AVVideoResolution360p];
    
    // 设置默认视频参数
    config.videoFrameRate = 20;
    config.videoMinFrameRate = 15;
    config.videoMaxKeyframeInterval = 60; // 2x fps
    
    // 设置默认码率（kbps → bps）
    config.videoBitRate = 2000 * 1000;      // 2000 kbps
    config.videoMinBitRate = 500 * 1000;    // 500 kbps
    
    return config;
}

+ (instancetype)configurationWithResolution:(AVVideoResolution)resolution {
    AVVideoConfiguration *config = [self defaultConfiguration];
    [config setResolution:resolution];
    return config;
}

#pragma mark - Resolution Management

- (void)setResolution:(AVVideoResolution)resolution {
    // 默认：采集和输出使用相同分辨率
    [self setCaptureResolution:resolution outputResolution:resolution];
}

- (void)setCaptureResolution:(AVVideoResolution)captureResolution
            outputResolution:(AVVideoResolution)outputResolution {
    // 设置输出分辨率（videoSize）
    CGSize outputSize = AVVideoResolutionSize(outputResolution);
    self.videoSize = outputSize;
    
    // 根据输出分辨率自动调整码率
    [self adjustBitrateForResolution:outputResolution];
}

- (void)adjustBitrateForResolution:(AVVideoResolution)resolution {
    NSUInteger maxBitrate, minBitrate;
    
    switch (resolution) {
        case AVVideoResolution360p:
            maxBitrate = 600;
            minBitrate = 300;
            break;
        case AVVideoResolution480p:
            maxBitrate = 900;
            minBitrate = 400;
            break;
        case AVVideoResolution540p:
            maxBitrate = 1500;
            minBitrate = 500;
            break;
        case AVVideoResolution720p:
            maxBitrate = 2000;
            minBitrate = 800;
            break;
    }
    
    self.videoBitRate = maxBitrate * 1000;      // Convert kbps to bps
    self.videoMinBitRate = minBitrate * 1000;   // Convert kbps to bps
}

- (AVVideoResolution)currentResolution {
    // 返回输出分辨率
    return [self currentOutputResolution];
}

- (AVVideoResolution)currentOutputResolution {
    // 根据 videoSize 返回输出分辨率
    CGSize size = self.videoSize;
    
    // 处理横屏和竖屏（统一为横屏比较）
    CGFloat width = MAX(size.width, size.height);
    CGFloat height = MIN(size.width, size.height);
    
    if (width == 640 && height == 360) {
        return AVVideoResolution360p;
    } else if (width == 854 && height == 480) {
        return AVVideoResolution480p;
    } else if (width == 960 && height == 540) {
        return AVVideoResolution540p;
    } else if (width == 1280 && height == 720) {
        return AVVideoResolution720p;
    }
    
    // 默认返回 720p
    return AVVideoResolution720p;
}

#pragma mark - Convenience Accessors

- (NSInteger)maxBitrateKbps {
    return self.videoBitRate / 1000;
}

- (NSInteger)minBitrateKbps {
    return self.videoMinBitRate / 1000;
}

#pragma mark - NSCopying

- (id)copyWithZone:(NSZone *)zone {
    // 调用父类的 copy 方法
    AVVideoConfiguration *copy = [super copyWithZone:zone];
    
    // 复制自己的属性
    copy.nickname = [self.nickname copy];
    copy.streamId = [self.streamId copy];
    copy.codec = self.codec;
    
    return copy;
}

#pragma mark - Description

- (NSString *)description {
    NSMutableString *desc = @"".mutableCopy;
    [desc appendFormat:@"<AVVideoConfiguration: %p>\n", self];
    [desc appendFormat:@"  nickname: %@\n", self.nickname];
    [desc appendFormat:@"  streamId: %@\n", self.streamId];
    [desc appendFormat:@"  codec: %@\n", AVVideoCodecString(self.codec)];
    [desc appendFormat:@"  videoSize: %@\n", NSStringFromCGSize(self.videoSize)];
    [desc appendFormat:@"  videoFrameRate: %lu\n", (unsigned long)self.videoFrameRate];
    [desc appendFormat:@"  videoBitRate: %lu kbps\n", (unsigned long)(self.videoBitRate / 1000)];
    [desc appendFormat:@"  videoMinBitRate: %lu kbps", (unsigned long)(self.videoMinBitRate / 1000)];
    return desc;
}

@end