package main

import (
	"crypto/md5"
	"encoding/hex"
	"fmt"
	"net/http"
	"time"
)

var imageSearchEngines []SearchEngine

func init() {
	imageSearchEngines = []SearchEngine{
		{Name: "Qwant", Func: wrapImageSearchFunc(PerformQwantImageSearch)},
		{Name: "Bing", Func: wrapImageSearchFunc(PerformBingImageSearch)},
		{Name: "DeviantArt", Func: wrapImageSearchFunc(PerformDeviantArtImageSearch)},
		//{Name: "Imgur", Func: wrapImageSearchFunc(PerformImgurImageSearch), Weight: 4}, // Image proxy not working
	}
}

func handleImageSearch(w http.ResponseWriter, settings UserSettings, query string, page int) {
	startTime := time.Now()

	cacheKey := CacheKey{Query: query, Page: page, Safe: settings.SafeSearch == "active", Lang: settings.SearchLanguage, Type: "image"}
	combinedResults := getImageResultsFromCacheOrFetch(cacheKey, query, settings.SafeSearch, settings.SearchLanguage, page)

	elapsedTime := time.Since(startTime)

	// Prepare the data to pass to the template
	data := map[string]interface{}{
		"Results":         combinedResults,
		"Query":           query,
		"Fetched":         fmt.Sprintf("%.2f %s", elapsedTime.Seconds(), Translate("seconds")), // Time for fetching
		"Page":            page,
		"HasPrevPage":     page > 1,
		"HasNextPage":     len(combinedResults) >= 50,
		"NoResults":       len(combinedResults) == 0,
		"LanguageOptions": languageOptions,
		"CurrentLang":     settings.SearchLanguage,
		"Theme":           settings.Theme,
		"Safe":            settings.SafeSearch,
		"IsThemeDark":     settings.IsThemeDark,
	}

	// Render the template without measuring the time
	renderTemplate(w, "images.html", data)
}

func getImageResultsFromCacheOrFetch(cacheKey CacheKey, query, safe, lang string, page int) []ImageSearchResult {
	cacheChan := make(chan []SearchResult)
	var combinedResults []ImageSearchResult

	go func() {
		results, exists := resultsCache.Get(cacheKey)
		if exists {
			printInfo("Cache hit")
			cacheChan <- results
		} else {
			printInfo("Cache miss")
			cacheChan <- nil
		}
	}()

	select {
	case results := <-cacheChan:
		if results == nil {
			combinedResults = fetchImageResults(query, safe, lang, page)
			if len(combinedResults) > 0 {
				resultsCache.Set(cacheKey, convertToSearchResults(combinedResults))
			}
		} else {
			_, _, imageResults := convertToSpecificResults(results)
			combinedResults = imageResults
		}
	case <-time.After(2 * time.Second):
		printInfo("Cache check timeout")
		combinedResults = fetchImageResults(query, safe, lang, page)
		if len(combinedResults) > 0 {
			resultsCache.Set(cacheKey, convertToSearchResults(combinedResults))
		}
	}

	return combinedResults
}

func fetchImageResults(query, safe, lang string, page int) []ImageSearchResult {
	var results []ImageSearchResult

	for _, engine := range imageSearchEngines {
		printInfo("Using image search engine: %s", engine.Name)

		searchResults, _, err := engine.Func(query, safe, lang, page)
		if err != nil {
			printWarn("Error performing image search with %s: %v", engine.Name, err)
			continue
		}

		for _, result := range searchResults {
			imageResult := result.(ImageSearchResult)
			if config.HardCacheDuration > 0 {
				// Generate hash from the original full-size image URL
				hasher := md5.New()
				hasher.Write([]byte(imageResult.Full))
				hash := hex.EncodeToString(hasher.Sum(nil))
				filename := hash + ".webp"

				// Set the Full URL to point to the cached image path
				cacheURL := "/image_cache/" + filename
				imageResult.ProxyFull = cacheURL

				// Assign the ID
				imageResult.ID = hash

				// Start caching in the background
				go func(originalURL, filename string) {
					_, err := cacheImage(originalURL, filename)
					if err != nil {
						printWarn("Failed to cache image %s: %v", originalURL, err)
					}
				}(imageResult.Full, filename)
			}
			results = append(results, imageResult)
		}

		if len(results) > 0 {
			break
		}
	}

	if len(results) == 0 {
		printWarn("No image results found for query: %s, trying other nodes", query)
		results = tryOtherNodesForImageSearch(query, safe, lang, page, []string{hostID})
	}

	return results
}

func wrapImageSearchFunc(f func(string, string, string, int) ([]ImageSearchResult, time.Duration, error)) func(string, string, string, int) ([]SearchResult, time.Duration, error) {
	return func(query, safe, lang string, page int) ([]SearchResult, time.Duration, error) {
		imageResults, duration, err := f(query, safe, lang, page)
		if err != nil {
			return nil, duration, err
		}
		searchResults := make([]SearchResult, len(imageResults))
		for i, result := range imageResults {
			searchResults[i] = result
		}
		return searchResults, duration, nil
	}
}