//
//  KMVerificationRSA.swift
//  PDF Reader Pro
//
//  Created by Niehaoyu on 2024/8/9.
//

import Cocoa
import CryptoKit
import Security
import CommonCrypto
import Foundation

@objc class KMVerificationRSA: NSObject {

    @objc func active(uniquesn: String, cdkey: String, model: String, os: String, language: String, appversion: String) -> String?  {
        var dictionary: [String: Any] = [:]
        if cdkey.isEmpty {
            dictionary = ["subscription": ["app_code":"com.imyfone.pdf"],
                                             "device": ["unique_sn":uniquesn,
                                                        "os":os,
                                                        "platform":"DMG",
                                                        "time_zone":"UTC",
                                                        "language":language,
                                                        "app_version":appversion]]
        } else {
            dictionary = ["subscription": ["app_code":"com.imyfone.pdf",
                                                              "email":cdkey],
                                             "device": ["unique_sn":uniquesn,
                                                        "os":os,
                                                        "platform":"DMG",
                                                        "time_zone":"UTC",
                                                        "language":language,
                                                        "app_version":appversion]]
        }

        if let jsonData = try? JSONSerialization.data(withJSONObject: dictionary, options:[]),
           let jsonString = String(data: jsonData, encoding: .utf8) {
            print(jsonString)
            if let publicKey = loadPublicKey() {
                let encryptedData = encrypt(plainText: jsonString, publicKey: publicKey)
                print("Encrypted data: \(encryptedData?.base64EncodedString() ?? "nil")")
                let encryptedString = encryptedData?.base64EncodedString();
                return encryptedString
                
                //Test
//                let dataToEncrypt = jsonString.data(using: .utf8)!
//                
//                if let encryptedDataChunks = encryptDataInChunks(data: dataToEncrypt, publicKey: publicKey) {
//                    print("Encrypted data chunks:")
//                    for chunk in encryptedDataChunks {
//                        print(chunk.base64EncodedString()) // 输出每个加密块
//                    }
//                    print("111")
//                }
//                
//                
//                let message = jsonString
//                if let messageData = message.data(using: .utf8) {
//                    if let publicKey = loadPublicKey() {
//                        if let encryptedChunks = encrypt(data: messageData, publicKey: publicKey) {
//                            let encryptedString = encryptedChunks.map { $0.base64EncodedString() }
//                            print("Encrypted data: \(encryptedString)")
//                            return encryptedString.first
//                        }
//                    }
//                }
            }
        }
        return nil
    }
    
    @objc func verify(uniquesn: String, model: String, os: String, language: String, appversion: String) -> String? {
       let dictionary: [String: Any] = ["subscription": ["app_code":"com.imyfone.pdf"],
                                        "device": ["unique_sn":uniquesn,
                                                   "os":os,
                                                   "platform":"DMG",
                                                   "time_zone":"UTC",
                                                   "language":language,
                                                   "app_version":appversion]]

        if let jsonData = try? JSONSerialization.data(withJSONObject: dictionary, options:[]),
           let jsonString = String(data: jsonData, encoding: .utf8) {
            print(jsonString)
            if let publicKey = loadPublicKey() {
                let encryptedData = encrypt(plainText: jsonString, publicKey: publicKey)
                print("Encrypted data: \(encryptedData?.base64EncodedString() ?? "nil")")
                let encryptedString = encryptedData?.base64EncodedString();
                return encryptedString
            }
            
            //Test
            let message = jsonString
            if let messageData = message.data(using: .utf8) {
                if let publicKey = loadPublicKey() {
                    if let encryptedChunks = encrypt(data: messageData, publicKey: publicKey) {
                        let encryptedString = encryptedChunks.map { $0.base64EncodedString() }
                        print("Encrypted data: \(encryptedString)")
                        return encryptedString.first
                    }
                }
            }
            
        }
        
        
        return nil
    }
    
    func encrypt(plainText: String, publicKey: SecKey) -> Data? {
        guard let data = plainText.data(using: .utf8) else {
            return nil
        }
        
        var error: Unmanaged<CFError>?
        let encryptedData = SecKeyCreateEncryptedData(publicKey, .rsaEncryptionPKCS1, data as CFData, &error)
        
        if let error = error?.takeRetainedValue() {
            print("Error encrypting data: \(error)")
            return nil
        }
        
        return encryptedData as Data?
    }
    
    func encrypt(data: Data, publicKey: SecKey) -> [Data]? {
        let maxChunkSize = 214 // 对于 RSA-2048，214 是最大加密长度
        var chunks = [Data]()
        var offset = 0

        while offset < data.count {
            let chunkSize = min(maxChunkSize, data.count - offset)
            let chunk = data.subdata(in: offset..<offset + chunkSize)
            if let encryptedData = SecKeyCreateEncryptedData(publicKey, .rsaEncryptionPKCS1, chunk as CFData, nil) {
                chunks.append(encryptedData as Data)
            } else {
                return nil // 加密失败
            }
            offset += chunkSize
        }
        
        return chunks
    }
    
    
    func loadPublicKey() -> SecKey? {

        let publicKeyString = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAqqYKtu5pbT3bhbOfZ7XFhw1IEiqGvx/z3YwvcrLvG6I+EBbim/YuDfSTqpcTZSjbMeLz8nCzkAsMakoimzI6XpNQOZN35cDCFkjn0vicpnfla2JPMxREwddblAz7u/EMdx71ElcY+UYfSu1QM0Lepc2QPWw9oaD/cNktH6xE6eogLEH0k8ZYP8YIzTW02og7mNtLVO1ssKQYUCIQ5LkKA7zypQul5upajE51rq49vdCoA98y2zBRTMXGM7tpa2rbXQ9fDMn5heCLVCXCHNXDwBMxNhURm7fEfxZPwq7DUmH8EWKXCKKhu+GP0c/eom50FzMxfN2wpQSgNfyNQ7bBgwIDAQAB"
        
        guard let data = Data(base64Encoded: publicKeyString) else {
            return nil
        }
        
        let options: [String: Any] = [
            kSecAttrKeyType as String: kSecAttrKeyTypeRSA,
            kSecAttrKeyClass as String: kSecAttrKeyClassPublic,
            kSecAttrKeySizeInBits as String: 4096
        ]
        
        var error: Unmanaged<CFError>?
        let publicKey = SecKeyCreateWithData(data as CFData, options as CFDictionary, &error)
        
        if let error = error?.takeRetainedValue() {
            print("Error loading public key: \(error)")
            return nil
        }
        
        return publicKey
    }
     
    func base64Encode(string: String) -> String? {
        // 将字符串转换为 Data
        guard let data = string.data(using: .utf8) else {
            print("Error converting string to Data.")
            return nil
        }
        
        // 使用 Data 的 base64EncodedString() 方法进行编码
        let base64String = data.base64EncodedString()
        return base64String
    }

    
    // RSA 分块加密
    func encryptDataInChunks(data: Data, publicKey: SecKey) -> [Data]? {
        let blockSize = SecKeyGetBlockSize(publicKey) - 11 // PKCS#1 v1.5 填充需要额外字节
        var encryptedChunks: [Data] = []
        
        var offset = 0
        while offset < data.count {
            let size = min(data.count - offset, blockSize) // 计算当前块大小
            let chunk = data.subdata(in: offset..<offset+size)
            
            var error: Unmanaged<CFError>?
            let encryptedData = SecKeyCreateEncryptedData(publicKey, .rsaEncryptionPKCS1, data as CFData, &error)
                                               
            guard let successData = encryptedData else {
                if let error = error?.takeRetainedValue() {
                    print("Encryption failed: \(error)")
                }
                return nil
            }
            
            encryptedChunks.append(successData as Data)
            offset += size
        }
        
        return encryptedChunks
    }
    
    func encrypt22(data: Data, publicKey: SecKey) -> [Data]? {
        let keySizeInBytes = 256 // 对于 RSA-2048，密钥大小为 256 字节
        let paddingSize = 11 // PKCS#1 填充大小
        let maxChunkSize = keySizeInBytes - paddingSize // 最大可加密数据大小

        var chunks = [Data]()
        var offset = 0

        while offset < data.count {
            let chunkSize = min(maxChunkSize, data.count - offset)
            let chunk = data.subdata(in: offset..<offset + chunkSize)
            
            var error: Unmanaged<CFError>?
            guard let encryptedData = SecKeyCreateEncryptedData(publicKey, .rsaEncryptionPKCS1, chunk as CFData, &error) else {
                print("Encryption error: \(error!.takeRetainedValue() as Error)")
                return nil
            }
            chunks.append(encryptedData as Data)
            offset += chunkSize
        }
        
        return chunks
    }
    
    
}