#include <iostream>
#include <fstream>
#include <crypto++/sha.h>
#include <crypto++/modes.h>
#include <crypto++/aes.h>
#include "meme/0.h"
#include "meme/1.h"
#include "meme/2.h"

using namespace std;
using namespace CryptoPP;

void decrypt_ecb(unsigned char *data, const int size,
				 const string& key, const string& file)
{
	byte hash[20];
	SHA1 sha1;
	sha1.CalculateDigest(hash,(byte*)&key[0],key.size());
	ECB_Mode<AES>::Decryption aes(hash,AES::DEFAULT_KEYLENGTH);

	aes.ProcessData((byte*)data,(byte*)data,size);
	ofstream out(file.c_str(),ios::binary);
	out.write((char*)data,size);
}

void decrypt_ctr(unsigned char *data, const int size,
				 const string& key, const string& file)
{
	byte hash[20];
	SHA1 sha1;
	sha1.CalculateDigest(hash,(byte*)&key[0],key.size());
	CTR_Mode<AES>::Decryption aes(hash,AES::DEFAULT_KEYLENGTH,hash);

	aes.ProcessData((byte*)data,(byte*)data,size);
	ofstream out(file.c_str(),ios::binary);
	out.write((char*)data,size);
}

static const int numQuestions=3;
static const string questions[numQuestions]={
	"How to solve the chicken and egg problem", //answer=6hfvbgsdef
	"What have I been",                         //answer=Tro11d
	"What do I need to go ahead"                //answer=Thek3yt0th3n3xtl3v3l
};

int main()
{
	cout<<"Which question?"<<endl;
	int question;
	cin>>question;
	cin.get(); //Remove the \n
	if(question<0 || question>=numQuestions) return 1;
	cout<<questions[question]<<"?"<<endl;
	string answer;
	getline(cin,answer);
	switch(question)
	{
		case 0:
			decrypt_ecb(meme_0_bmp_enc,meme_0_bmp_enc_len,answer,"0.bmp");
			break;
		case 1:
			decrypt_ctr(meme_1_ogg_enc,meme_1_ogg_enc_len,answer,"1.ogg");
			break;
		case 2:
			decrypt_ctr(meme_2_jpg_enc,meme_2_jpg_enc_len,answer,"2.jpg");
			break;
	}
}