/*
* Hash Functions
* (C) 2015 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#include <botan/hash.h>
#include <botan/scan_name.h>

#if defined(BOTAN_HAS_ADLER32)
  #include <botan/adler32.h>
#endif

#if defined(BOTAN_HAS_CRC24)
  #include <botan/crc24.h>
#endif

#if defined(BOTAN_HAS_CRC32)
  #include <botan/crc32.h>
#endif

#if defined(BOTAN_HAS_GOST_34_11)
  #include <botan/gost_3411.h>
#endif

#if defined(BOTAN_HAS_KECCAK)
  #include <botan/keccak.h>
#endif

#if defined(BOTAN_HAS_MD4)
  #include <botan/md4.h>
#endif

#if defined(BOTAN_HAS_MD5)
  #include <botan/md5.h>
#endif

#if defined(BOTAN_HAS_RIPEMD_160)
  #include <botan/rmd160.h>
#endif

#if defined(BOTAN_HAS_SHA1)
  #include <botan/sha160.h>
#endif

#if defined(BOTAN_HAS_SHA2_32)
  #include <botan/sha2_32.h>
#endif

#if defined(BOTAN_HAS_SHA2_64)
  #include <botan/sha2_64.h>
#endif

#if defined(BOTAN_HAS_SHA3)
  #include <botan/sha3.h>
#endif

#if defined(BOTAN_HAS_SHAKE)
  #include <botan/shake.h>
#endif

#if defined(BOTAN_HAS_SKEIN_512)
  #include <botan/skein_512.h>
#endif

#if defined(BOTAN_HAS_TIGER)
  #include <botan/tiger.h>
#endif

#if defined(BOTAN_HAS_WHIRLPOOL)
  #include <botan/whrlpool.h>
#endif

#if defined(BOTAN_HAS_PARALLEL_HASH)
  #include <botan/par_hash.h>
#endif

#if defined(BOTAN_HAS_COMB4P)
  #include <botan/comb4p.h>
#endif

#if defined(BOTAN_HAS_BLAKE2B)
  #include <botan/blake2b.h>
#endif

#if defined(BOTAN_HAS_OPENSSL)
  #include <botan/internal/openssl.h>
#endif

namespace Botan {

std::unique_ptr<HashFunction> HashFunction::create(const std::string& algo_spec,
                                                   const std::string& provider)
   {
#if defined(BOTAN_HAS_OPENSSL)
   if(provider.empty() || provider == "openssl")
      {
      if(auto hash = make_openssl_hash(algo_spec))
         return hash;

      if(!provider.empty())
         return nullptr;
      }
#endif

   // TODO: CommonCrypto hashes

   if(provider.empty() == false && provider != "base")
      return nullptr; // unknown provider

#if defined(BOTAN_HAS_SHA1)
   if(algo_spec == "SHA-160" ||
      algo_spec == "SHA-1" ||
      algo_spec == "SHA1")
      {
      return std::unique_ptr<HashFunction>(new SHA_160);
      }
#endif

#if defined(BOTAN_HAS_SHA2_32)
   if(algo_spec == "SHA-224")
      {
      return std::unique_ptr<HashFunction>(new SHA_224);
      }

   if(algo_spec == "SHA-256")
      {
      return std::unique_ptr<HashFunction>(new SHA_256);
      }
#endif

#if defined(BOTAN_HAS_SHA2_64)
   if(algo_spec == "SHA-384")
      {
      return std::unique_ptr<HashFunction>(new SHA_384);
      }

   if(algo_spec == "SHA-512")
      {
      return std::unique_ptr<HashFunction>(new SHA_512);
      }

   if(algo_spec == "SHA-512-256")
      {
      return std::unique_ptr<HashFunction>(new SHA_512_256);
      }
#endif

#if defined(BOTAN_HAS_RIPEMD_160)
   if(algo_spec == "RIPEMD-160")
      {
      return std::unique_ptr<HashFunction>(new RIPEMD_160);
      }
#endif

#if defined(BOTAN_HAS_WHIRLPOOL)
   if(algo_spec == "Whirlpool")
      {
      return std::unique_ptr<HashFunction>(new Whirlpool);
      }
#endif

#if defined(BOTAN_HAS_MD5)
   if(algo_spec == "MD5")
      {
      return std::unique_ptr<HashFunction>(new MD5);
      }
#endif

#if defined(BOTAN_HAS_MD4)
   if(algo_spec == "MD4")
      {
      return std::unique_ptr<HashFunction>(new MD4);
      }
#endif

#if defined(BOTAN_HAS_GOST_34_11)
   if(algo_spec == "GOST-R-34.11-94" || algo_spec == "GOST-34.11")
      {
      return std::unique_ptr<HashFunction>(new GOST_34_11);
      }
#endif

#if defined(BOTAN_HAS_ADLER32)
   if(algo_spec == "Adler32")
      {
      return std::unique_ptr<HashFunction>(new Adler32);
      }
#endif

#if defined(BOTAN_HAS_CRC24)
   if(algo_spec == "CRC24")
      {
      return std::unique_ptr<HashFunction>(new CRC24);
      }
#endif

#if defined(BOTAN_HAS_CRC32)
   if(algo_spec == "CRC32")
      {
      return std::unique_ptr<HashFunction>(new CRC32);
      }
#endif

   const SCAN_Name req(algo_spec);

#if defined(BOTAN_HAS_TIGER)
   if(req.algo_name() == "Tiger")
      {
      return std::unique_ptr<HashFunction>(
         new Tiger(req.arg_as_integer(0, 24),
                   req.arg_as_integer(1, 3)));
      }
#endif

#if defined(BOTAN_HAS_SKEIN_512)
   if(req.algo_name() == "Skein-512")
      {
      return std::unique_ptr<HashFunction>(
         new Skein_512(req.arg_as_integer(0, 512), req.arg(1, "")));
      }
#endif

#if defined(BOTAN_HAS_BLAKE2B)
   if(req.algo_name() == "Blake2b")
      {
      return std::unique_ptr<HashFunction>(
         new Blake2b(req.arg_as_integer(0, 512)));
   }
#endif

#if defined(BOTAN_HAS_KECCAK)
   if(req.algo_name() == "Keccak-1600")
      {
      return std::unique_ptr<HashFunction>(
         new Keccak_1600(req.arg_as_integer(0, 512)));
      }
#endif

#if defined(BOTAN_HAS_SHA3)
   if(req.algo_name() == "SHA-3")
      {
      return std::unique_ptr<HashFunction>(
         new SHA_3(req.arg_as_integer(0, 512)));
      }
#endif

#if defined(BOTAN_HAS_SHAKE)
   if(req.algo_name() == "SHAKE-128")
      {
      return std::unique_ptr<HashFunction>(new SHAKE_128(req.arg_as_integer(0, 128)));
      }
   if(req.algo_name() == "SHAKE-256")
      {
      return std::unique_ptr<HashFunction>(new SHAKE_256(req.arg_as_integer(0, 256)));
      }
#endif

#if defined(BOTAN_HAS_WHIRLPOOL)
   if(req.algo_name() == "Whirlpool")
      {
      return std::unique_ptr<HashFunction>(new Whirlpool);
      }
#endif

#if defined(BOTAN_HAS_PARALLEL_HASH)
   if(req.algo_name() == "Parallel")
      {
      std::vector<std::unique_ptr<HashFunction>> hashes;

      for(size_t i = 0; i != req.arg_count(); ++i)
         {
         auto h = HashFunction::create(req.arg(i));
         if(!h)
            {
            return nullptr;
            }
         hashes.push_back(std::move(h));
         }

      return std::unique_ptr<HashFunction>(new Parallel(hashes));
      }
#endif

#if defined(BOTAN_HAS_COMB4P)
   if(req.algo_name() == "Comb4P" && req.arg_count() == 2)
      {
      std::unique_ptr<HashFunction> h1(HashFunction::create(req.arg(0)));
      std::unique_ptr<HashFunction> h2(HashFunction::create(req.arg(1)));

      if(h1 && h2)
         return std::unique_ptr<HashFunction>(new Comb4P(h1.release(), h2.release()));
      }
#endif


   return nullptr;
   }

//static
std::unique_ptr<HashFunction>
HashFunction::create_or_throw(const std::string& algo,
                              const std::string& provider)
   {
   if(auto hash = HashFunction::create(algo, provider))
      {
      return hash;
      }
   throw Lookup_Error("Hash", algo, provider);
   }

std::vector<std::string> HashFunction::providers(const std::string& algo_spec)
   {
   return probe_providers_of<HashFunction>(algo_spec, {"base", "openssl"});
   }

}