package core

import (
	"fmt"
	"searchEngine/core/analyzer"
	"searchEngine/core/index"
	"searchEngine/core/ingest"
	"searchEngine/core/search"
	"sync"
)

type Engine struct {
	idx *index.InvertedIndex
}

func NewEngine() *Engine {
	return &Engine{
		idx: index.New(),
	}
}

func (e *Engine) Index() *index.InvertedIndex {
	return e.idx
}

func (e *Engine) IndexDump(filePath string, numWorkers int) error {
	if numWorkers <= 0 {
		numWorkers = 4
	}

	jobQueue := make(chan ingest.Page, 100)
	var wg sync.WaitGroup

	for i := 0; i < numWorkers; i++ {
		wg.Go(func() {
			for page := range jobQueue {
				tokens := analyzer.ProcessText(page.Text)
				e.idx.Add(page.Id, page.Title, tokens)
			}
		})
	}

	err := ingest.IngestWikiDump(filePath, jobQueue)
	close(jobQueue)
	wg.Wait()

	if err != nil {
		return fmt.Errorf("failed to ingest wiki dump: %w", err)
	}

	return nil
}

func (e *Engine) Search(query string) []string {
	return search.Search(e.idx, query)
}