package main

const ArraySize2 = 7

// HashTable structure
type HashTable2 struct {
	array [ArraySize2]*bucket2
}

// bucket structure
type bucket2 struct {
	key   string
	value int
	next  *bucket2
}

// Insert will take in a key and will add the item to the hash table array.
func (h *HashTable2) Insert(key string, value int) {
	index := hash(key)
	h.array[index].insert(key, value)
}

// Search will take in a key and RETURN true if that key is stored in the hash table.
func (h *HashTable2) Search(key string) bool {
	index := hash(key)
	return h.array[index].search(key)
}

// Delete will take in a key and DELETE it from the hash table.
func (h *HashTable2) Delete(key string) {
	index := hash(key)
	h.array[index].delete(key)
}

// insert will take in a key and add it to the bucket.
func (b *bucket2) insert(k string, v int) {
	if b.search(k) {
		b.value = v
	} else {
		newBucket := &bucket2{k, v, nil}
		newBucket.next = b
		*b = *newBucket
	}
}

// search will take in a key and return true if it's in the bucket.
func (b *bucket2) search(k string) bool {
	if b == nil {
		return false
	}
	if b.key == k {
		return true
	}

	return b.next.search(k)
}

// delete will take in a key and delete the corresponding node in the bucket.
func (b *bucket2) delete(k string) {
	if b.key == k {
		b = b.next
		return
	}
	prevB := b
	for b != nil && b.key != k {
		prevB = b
		b = b.next
	}
	if b != nil {
		prevB.next = b.next
	}
}

// hash is the basic hashing function.
func hash2(key string) int {
	sum := 0
	for _, v := range key {
		sum += int(v)
	}
	return sum % ArraySize2
}

func Init() *HashTable2 {
	result := &HashTable2{}
	for i := range result.array {
		result.array[i] = &bucket2{}
	}
	return result
}