package brotli

import 

/* Copyright 2010 Google Inc. All Rights Reserved.

   Distributed under MIT license.
   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/

/* For BUCKET_SWEEP == 1, enabling the dictionary lookup makes compression
   a little faster (0.5% - 1%) and it compresses 0.15% better on small text
   and HTML inputs. */

func (*hashLongestMatchQuickly) () uint {
	return 8
}

func (*hashLongestMatchQuickly) () uint {
	return 8
}

/* HashBytes is the function that chooses the bucket to place
   the address in. The HashLongestMatch and hashLongestMatchQuickly
   classes have separate, different implementations of hashing. */
func ( *hashLongestMatchQuickly) ( []byte) uint32 {
	var  uint64 = ((binary.LittleEndian.Uint64() << (64 - 8*.hashLen)) * kHashMul64)

	/* The higher bits contain more mixture from the multiplication,
	   so we take our results from there. */
	return uint32( >> (64 - .bucketBits))
}

/* A (forgetful) hash table to the data seen by the compressor, to
   help create backward references to previous data.

   This is a hash map of fixed size (1 << 16). Starting from the
   given index, 1 buckets are used to store values of a key. */
type hashLongestMatchQuickly struct {
	hasherCommon

	bucketBits    uint
	bucketSweep   int
	hashLen       uint
	useDictionary bool

	buckets []uint32
}

func ( *hashLongestMatchQuickly) ( *encoderParams) {
	.buckets = make([]uint32, 1<<.bucketBits+.bucketSweep)
}

func ( *hashLongestMatchQuickly) ( bool,  uint,  []byte) {
	var  uint = (4 << .bucketBits) >> 7
	/* Partial preparation is 100 times slower (per socket). */
	if  &&  <=  {
		var  uint
		for  = 0;  < ; ++ {
			var  uint32 = .HashBytes([:])
			for  := 0;  < .bucketSweep; ++ {
				.buckets[+uint32()] = 0
			}
		}
	} else {
		/* It is not strictly necessary to fill this buffer here, but
		   not filling will make the results of the compression stochastic
		   (but correct). This is because random data would cause the
		   system to find accidentally good backward references here and there. */
		for  := range .buckets {
			.buckets[] = 0
		}
	}
}

/* Look at 5 bytes at &data[ix & mask].
   Compute a hash from these, and store the value somewhere within
   [ix .. ix+3]. */
func ( *hashLongestMatchQuickly) ( []byte,  uint,  uint) {
	var  uint32 = .HashBytes([&:])
	var  uint32 = uint32(>>3) % uint32(.bucketSweep)
	/* Wiggle the value with the bucket sweep range. */
	.buckets[+] = uint32()
}

func ( *hashLongestMatchQuickly) ( []byte,  uint,  uint,  uint) {
	var  uint
	for  = ;  < ; ++ {
		.Store(, , )
	}
}

func ( *hashLongestMatchQuickly) ( uint,  uint,  []byte,  uint) {
	if  >= .HashTypeLength()-1 &&  >= 3 {
		/* Prepare the hashes for three last bytes of the last write.
		   These could not be calculated before, since they require knowledge
		   of both the previous and the current block. */
		.Store(, , -3)
		.Store(, , -2)
		.Store(, , -1)
	}
}

func (*hashLongestMatchQuickly) ( []int) {
}

/* Find a longest backward match of &data[cur_ix & ring_buffer_mask]
   up to the length of max_length and stores the position cur_ix in the
   hash table.

   Does not look for matches longer than max_length.
   Does not look for matches further away than max_backward.
   Writes the best match into |out|.
   |out|->score is updated only if a better match is found. */
func ( *hashLongestMatchQuickly) ( *encoderDictionary,  []byte,  uint,  []int,  uint,  uint,  uint,  uint,  uint,  *hasherSearchResult) {
	var  uint = .len
	var  uint =  & 
	var  uint32 = .HashBytes([:])
	var  int = int([+])
	var  uint = .score
	var  uint = .score
	var  uint = 
	var  uint = uint([0])
	var  uint =  - 
	var  []uint32
	.len_code_delta = 0
	if  <  {
		 &= uint(uint32())
		if  == int([+]) {
			var  uint = findMatchLengthWithLimit([:], [:], )
			if  >= 4 {
				var  uint = backwardReferenceScoreUsingLastDistance(uint())
				if  <  {
					 = 
					 = uint()
					.len = uint()
					.distance = 
					.score = 
					 = int([+])
					if .bucketSweep == 1 {
						.buckets[] = uint32()
						return
					}
				}
			}
		}
	}

	if .bucketSweep == 1 {
		var  uint
		var  uint

		/* Only one to look for, don't bother to prepare for a loop. */
		 = uint(.buckets[])

		.buckets[] = uint32()
		 =  - 
		 &= uint(uint32())
		if  != int([+]) {
			return
		}

		if  == 0 ||  >  {
			return
		}

		 = findMatchLengthWithLimit([:], [:], )
		if  >= 4 {
			var  uint = backwardReferenceScore(uint(), )
			if  <  {
				.len = uint()
				.distance = 
				.score = 
				return
			}
		}
	} else {
		 = .buckets[:]
		var  int
		 = uint([0])
		 = [1:]
		for  = 0;  < .bucketSweep; (func() { ++;  := ;  = [1:];  = uint([0]) })() {
			var  uint =  - 
			var  uint
			 &= uint(uint32())
			if  != int([+]) {
				continue
			}

			if  == 0 ||  >  {
				continue
			}

			 = findMatchLengthWithLimit([:], [:], )
			if  >= 4 {
				var  uint = backwardReferenceScore(uint(), )
				if  <  {
					 = 
					 = uint()
					.len = 
					.distance = 
					.score = 
					 = int([+])
				}
			}
		}
	}

	if .useDictionary &&  == .score {
		searchInStaticDictionary(, , [:], , +, , , true)
	}

	.buckets[+uint32((>>3)%uint(.bucketSweep))] = uint32()
}