# 模式，文件，自己的公钥从哪里来，别人的公钥从哪里来
import base64

from entity.Letter import Letter
from itsdangerous import base64_encode
from tool import PriKeyHelper
from tool.PriKeyHelper import getUserKey
from tool.asymmetric import RSA
from tool.symmetric.AES import AESUtils
from tool.symmetric.SM4 import encrypt_ecb, decrypt_cbc_with_iv, encrypt_cbc_with_iv
from Crypto.Random import get_random_bytes


# 两个变量，记录信封
letterWay = ""
letterMode = ""
letterSymKey = b""

def main():
    letter = Letter()
    # 用户输入各种数据填充letter字段
    path = selectFile()

    with open(path,"rb") as f:
        data = f.read()
    letter.fileName = "交给你了"
    letter.recvPubKey = getRecvPubKey()
    letter.senderPubKey = getSenderPubKey()
    letter.fileBase64, akey = SymEncryption(base64_encode(data).decode("utf-8"),letterSymKey)
    # data = "Hello, AES!"
    letter.encryptKey = getEncryptKey()
    letter.encryptType = getEncryptType()

    letter.sign = getSign(data)



    print(letter.sign)
    print(letter.encryptType)
    print(letter.encryptKey)
    print(letter.recvPubKey)
    print(letter.senderPubKey)


    # 获取用户的公私钥对进行签名
    # 使用对方的公钥进行加密
    # 发送信件
    return letter # 方便recv测试，以后可以删除。
    pass
def selectFile() -> str:
    s = input("输入文件路径:")
    return s

def sendLetter(letter: Letter, target="192.168.195.162:8426"):
    # 向目标ip和端口发送指定的信件
    pass


# 选择对称加密的方法和模式(aes/sm4)
def selectSymEncryptionChoice():
    global letterWay, letterMode
    encryWay = ""
    encryMode = ""

    # 选择加密算法
    while True:
        encryWay = input("Choose the way for encryption (aes/sm4): ").strip().lower()  # 统一转成小写
        if encryWay in ["aes", "sm4"]:
            letterWay = encryWay
            print(f"You have selected '{encryWay}' encryption.")
            break  # 输入有效后退出循环
        else:
            print("Invalid choice. Please enter 'aes' or 'sm4'.")

    # 选择加密算法的模式
    while True:
        if encryWay == "aes":
            encryMode = input("Choose the encryption mode (ecb/cbc/cfb/ofb): ").strip().lower()
            if encryMode in ["ecb", "cbc", "cfb", "ofb"]:
                letterMode = encryMode
                print(f"You have selected '{encryMode}' encryption mode.")
                break  # 输入有效后退出循环
            else:
                print("Invalid choice. Please enter ecb/cbc/cfb/ofb")

        elif encryWay == "sm4":
            encryMode = input("Choose the encryption mode (ecb/cbc): ").strip().lower()
            if encryMode in ["ecb", "cbc"]:
                letterMode = encryMode
                print(f"You have selected '{encryMode}' encryption mode.")
                break  # 输入有效后退出循环
            else:
                print("Invalid choice. Please enter ecb/cbc")

    return encryWay, encryMode


# 使用对称加密，返回加密后的数据和随机生成的密钥
def SymEncryption(encryData, key: bytes = None):

    global letterSymKey
    # 获得加密的方法和加密的模式
    way, mode = selectSymEncryptionChoice()

    if way == "aes":
        aesUtils = AESUtils(key)
        encryptedData, trueKey = aesUtils.encrypt(encryData, mode=mode)  # 这里encryData要改为文件内容
        letterSymKey = trueKey

        return encryptedData,trueKey

    if way == "sm4":
        key = get_random_bytes(16)
        if mode == "ecb":
            encrypted_data = encrypt_ecb(encryData, key)
        # mode 为 cbc
        else:
            encrypted_data = encrypt_cbc_with_iv(encryData, key)
        letterSymKey = key
        return encrypted_data, key

# 获得签名
def getSign(document_bytes):

    #计算文件bytes
    priKey, pubKey = PriKeyHelper.getUserKey()
    signDocuHash = RSA.sign_message(document_bytes, priKey)

    return signDocuHash

def getEncryptType():
    encryType = f"{letterWay}_{letterMode}".upper()

    return encryType

# 对称密钥，返回的是使用接收方公钥加密后的密钥
def getEncryptKey():
    rsaEncrySymKey = RSA.encrypt_message(letterSymKey, getRecvPubKey())

    return base64.b64encode(rsaEncrySymKey).decode("utf-8")

# 获得接收方的公钥
def getRecvPubKey():
    # recPubKey = input("plz input Receiver's Public Key: ")
    recPubKey = getUserKey()[1]
    return recPubKey

# 获得发送方的公钥
def getSenderPubKey():
    privateKey, publicKey = getUserKey()
    return publicKey


if __name__ == "__main__":
    # 示例数据和密钥
    # data = "Hello, AES!"
    #
    # data, akey = SymEncryption(data)

    # print(data,akey)
    #
    # encryptType = f"{letterWay}_{letterMode}".upper()
    # print(encryptType)

    main()