import numpy as np
from scipy.signal import chirp
from typing import Union, List
class JammingSignalAlgo:
    """
    雷达干扰信号生成算法库
    支持噪声干扰、欺骗干扰、智能干扰等多种模式
    """

    @staticmethod
    def generate_noise_jam(
            bandwidth: float,
            duration: float,
            sample_rate: float,
            jamming_type: str = "gaussian"
    ) -> np.ndarray:
        """
        生成噪声干扰信号
        :param bandwidth: 干扰带宽(Hz)
        :param duration: 干扰持续时间(s)
        :param sample_rate: 采样率(Hz)
        :param jamming_type: 噪声类型(gaussian/blanket/spot)
        :return: 复数干扰信号
        """
        nsamples = int(duration * sample_rate)

        if jamming_type == "gaussian":
            # 高斯白噪声（全频段均匀干扰）
            return np.random.normal(0, 1, nsamples) + 1j * np.random.normal(0, 1, nsamples)

        elif jamming_type == "blanket":
            # 毯式噪声（带限增强）
            noise = np.random.normal(0, 1, nsamples)
            fft_sig = np.fft.fft(noise)
            freqs = np.fft.fftfreq(nsamples, 1 / sample_rate)
            mask = np.abs(freqs) <= bandwidth / 2
            return np.fft.ifft(fft_sig * mask).astype(np.complex64)

        elif jamming_type == "spot":
            # 点频噪声（针对特定频点）
            t = np.arange(nsamples) / sample_rate
            carrier = np.exp(1j * 2 * np.pi * bandwidth / 2 * t)
            return (np.random.normal(0, 1, nsamples) * carrier).astype(np.complex64)

        else:
            raise ValueError(f"未知噪声类型: {jamming_type}")

    @staticmethod
    def generate_deceptive_jam(
            radar_params: dict,
            false_targets: List[dict],
            sample_rate: float
    ) -> np.ndarray:
        """
        生成欺骗式干扰信号（假目标）
        :param radar_params: 雷达参数 {
            "pulse_width": 脉宽(s),
            "bandwidth": 带宽(Hz),
            "prf": 脉冲重复频率(Hz)
        }
        :param false_targets: 假目标参数列表 [{
            "delay": 时延(s),
            "doppler": 多普勒频移(Hz),
            "amplitude": 幅度系数(0-1)
        }]
        :param sample_rate: 采样率(Hz)
        :return: 复数干扰信号
        """
        pw = radar_params["pulse_width"]
        bw = radar_params["bandwidth"]
        nsamples = int(pw * sample_rate)

        # 生成基础雷达信号（LFM）
        t = np.linspace(0, pw, nsamples)
        chirp_signal = chirp(t, f0=0, t1=pw, f1=bw, phi=90, method='linear')
        chirp_signal = chirp_signal.astype(np.complex64)

        # 合成假目标
        jam_signal = np.zeros_like(chirp_signal)
        for target in false_targets:
            delay_samples = int(target["delay"] * sample_rate)
            doppler_phase = 2 * np.pi * target["doppler"] * t
            shifted_sig = np.roll(chirp_signal, delay_samples) * \
                          np.exp(1j * doppler_phase) * \
                          target["amplitude"]
            jam_signal += shifted_sig[:len(chirp_signal)]

        return jam_signal

    @staticmethod
    def generate_drgm_jam(
            radar_signal: np.ndarray,
            memory_depth: int = 5,
            modulation: str = "amplitude"
    ) -> np.ndarray:
        """
        数字射频存储器(DRGM)干扰
        :param radar_signal: 截获的雷达信号
        :param memory_depth: 存储深度（复制次数）
        :param modulation: 调制方式(amplitude/phase/frequency)
        :return: 干扰信号
        """
        jam_signal = np.array([])

        for i in range(memory_depth):
            if modulation == "amplitude":
                mod_signal = radar_signal * (0.8 + 0.2 * np.random.rand())
            elif modulation == "phase":
                mod_signal = radar_signal * np.exp(1j * np.pi / 4 * i)
            elif modulation == "frequency":
                mod_signal = radar_signal * np.exp(1j * 2 * np.pi * 0.01 * i * np.arange(len(radar_signal)))
            else:
                mod_signal = radar_signal

            jam_signal = np.concatenate([jam_signal, mod_signal])

        return jam_signal

    @staticmethod
    def generate_smart_jam(
            radar_signal: np.ndarray,
            sample_rate: float,
            jamming_mode: str = "repeater"
    ) -> np.ndarray:
        """
        智能干扰（认知电子战）
        :param radar_signal: 截获的雷达信号
        :param sample_rate: 采样率
        :param jamming_mode: 干扰模式(repeater/velocity_deception/range_deception)
        :return: 干扰信号
        """
        if jamming_mode == "repeater":
            # 转发式干扰（延迟转发）
            return np.roll(radar_signal, int(0.1 * sample_rate))

        elif jamming_mode == "velocity_deception":
            # 速度欺骗（多普勒调制）
            t = np.arange(len(radar_signal)) / sample_rate
            return radar_signal * np.exp(1j * 2 * np.pi * 1e4 * t)

        elif jamming_mode == "range_deception":
            # 距离欺骗（时域复制）
            return np.concatenate([
                radar_signal[:len(radar_signal) // 2],
                radar_signal[:len(radar_signal) // 2]
            ])

        else:
            raise ValueError(f"未知智能干扰模式: {jamming_mode}")


# ==================== 使用示例 ====================
if __name__ == "__main__":
    # 示例1：生成噪声干扰
    noise_jam = JammingSignalAlgo.generate_noise_jam(
        bandwidth=10e6,
        duration=0.1,
        sample_rate=100e6,
        jamming_type="blanket"
    )
    print(f"噪声干扰信号长度：{len(noise_jam)} samples")

    # 示例2：生成欺骗干扰
    false_targets = [
        {"delay": 2e-6, "doppler": 1e4, "amplitude": 0.7},
        {"delay": 5e-6, "doppler": -5e3, "amplitude": 0.3}
    ]
    deceptive_jam = JammingSignalAlgo.generate_deceptive_jam(
        radar_params={"pulse_width": 50e-6, "bandwidth": 100e6, "prf": 1e3},
        false_targets=false_targets,
        sample_rate=200e6
    )
    print(f"欺骗干扰信号峰值幅度：{np.max(np.abs(deceptive_jam)):.2f}")

    # 示例3：DRGM干扰
    radar_signal = np.exp(1j * 2 * np.pi * 1e6 * np.arange(1000) / 100e6)
    drgm_jam = JammingSignalAlgo.generate_drgm_jam(
        radar_signal,
        memory_depth=3,
        modulation="phase"
    )
    print(f"DRGM干扰信号维度：{drgm_jam.shape}")
# 算法	处理增益	时延	适用场景
# 自适应滤波	15-25 dB	O(N)	对抗噪声干扰
# PCA降噪	10-20 dB	O(n³)	多通道系统
# CFAR检测	-	        O(N)	欺骗干扰抑制
# 时频滤波	20-40 dB	O(NlogN)点频干扰
# MTI滤波	30-50 dB	O(N)	动目标检测
# 欺骗检测	-	        O(N²)	DRFM干扰