package index

import "sync"

type Posting struct {
	DocId int
	Count int
}
type InvertedIndex struct {
	Mu       sync.RWMutex
	Data     map[string][]Posting
	DocNames map[int]string
}

func New() *InvertedIndex {
	return &InvertedIndex{
		Data:     make(map[string][]Posting),
		DocNames: make(map[int]string),
	}
}

func (idx *InvertedIndex) Add(docID int, title string, tokens []string) {

	tokenCounts := make(map[string]int)
	for _, token := range tokens {
		tokenCounts[token]++
	}

	idx.Mu.Lock()
	defer idx.Mu.Unlock()

	idx.DocNames[docID] = title

	for token, count := range tokenCounts {
		idx.Data[token] = append(idx.Data[token], Posting{
			DocId: docID,
			Count: count,
		})
	}
}