package services

import (
	"encoding/base64"
	"fmt"
	"net/http"
	"net/http/httptest"
	"net/url"
	"strings"
	"sync/atomic"
	"testing"
	"time"
)

func TestExtractVideoPreviewURLFindsEnvatoPreview(t *testing.T) {
	html := `<script type="application/ld+json">{"contentUrl":"https://video-previews.elements.envatousercontent.com/ad0a3abc-7eb0-4075-8f68-8198f9a08777/watermarked_preview/watermarked_preview.mp4"}</script>`
	got := firstNonEmpty(extractJSONLDValue(html, "contentUrl"), extractVideoPreviewURL(html))
	want := "https://video-previews.elements.envatousercontent.com/ad0a3abc-7eb0-4075-8f68-8198f9a08777/watermarked_preview/watermarked_preview.mp4"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestExtractVideoPreviewURLFindsGenericM3U8(t *testing.T) {
	html := `<script>window.preview="https:\/\/cdn.example.com\/preview\/master.m3u8?token=abc"</script>`
	got := extractVideoPreviewURL(html)
	want := "https://cdn.example.com/preview/master.m3u8?token=abc"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestDeriveEnvatoPreviewFromThumbnail(t *testing.T) {
	thumb := "https://elements-resized.envatousercontent.com/elements-video-cover-images/ad0a3abc-7eb0-4075-8f68-8198f9a08777/video_preview/video_preview_0000.jpg?w=1200&amp;h=630"
	got := deriveEnvatoPreviewFromThumbnail(thumb)
	want := "https://elements-resized.envatousercontent.com/elements-video-cover-images/ad0a3abc-7eb0-4075-8f68-8198f9a08777/watermarked_preview/watermarked_preview.mp4"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestExtractEnvatoPreviewFromHydration(t *testing.T) {
	payload := `{"contentUrl":"https://video-previews.elements.envatousercontent.com/example/watermarked_preview/watermarked_preview.mp4"}`
	html := `<script>window.INITIAL_HYDRATION_DATA="` + base64.StdEncoding.EncodeToString([]byte(payload)) + `";window.INITIAL_HYDRATION_DATA_ENCODED=true;</script>`
	got := extractEnvatoPreviewFromHydration(html)
	want := "https://video-previews.elements.envatousercontent.com/example/watermarked_preview/watermarked_preview.mp4"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestCollectEnvatoPreviewURLFindsOgVideo(t *testing.T) {
	html := `<meta property="og:video" content="https://video-previews.elements.envatousercontent.com/example/watermarked_preview/watermarked_preview.mp4">`
	got := collectEnvatoPreviewURL(html, "", "", "")
	want := "https://video-previews.elements.envatousercontent.com/example/watermarked_preview/watermarked_preview.mp4"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestIsUsefulGoogleVideoResultRejectsMusicResults(t *testing.T) {
	result := SearchResult{
		Title:   "Couple Friendly Sad Bgm Movie Best Bgm",
		Link:    "https://www.youtube.com/watch?v=LGP4wiXSw8c",
		Snippet: "romantic bgm soundtrack",
	}
	if isUsefulGoogleVideoResult(result) {
		t.Fatal("expected bgm/music result to be rejected")
	}
}

func TestExtractVideoObjectJSONLD(t *testing.T) {
	html := `<script type="application/ld+json">{"@context":"https://schema.org","@type":"VideoObject","name":"Smiling Man and Woman Waving at Camera","description":"Close up shot of a smiling couple waving.","thumbnailUrl":"https://elements-resized.envatousercontent.com/example/video_preview/video_preview_0001.jpg","contentUrl":"https://video-previews.elements.envatousercontent.com/example/watermarked_preview/watermarked_preview.mp4"}</script>`
	meta := extractVideoObjectJSONLD(html)
	if meta.Name != "Smiling Man and Woman Waving at Camera" {
		t.Fatalf("unexpected name: %#v", meta)
	}
	if meta.ContentURL == "" || meta.ThumbnailURL == "" || meta.Description == "" {
		t.Fatalf("expected full video object metadata, got %#v", meta)
	}
}

func TestCleanArtgridTitle(t *testing.T) {
	got := cleanArtgridTitle("movie film moving slowly from a reel by Arthur Cauty | Royalty Free Stock Footage – Artgrid.io")
	want := "movie film moving slowly from a reel"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestCanonicalizeArtgridLinkFromArtlist(t *testing.T) {
	got := canonicalizeArtgridLink("https://artlist.io/stock-footage/clip/movie-film-moving-slowly-from-a-reel/114756")
	want := "https://artgrid.io/clip/114756/movie-film-moving-slowly-from-a-reel"
	if got != want {
		t.Fatalf("expected %q, got %q", want, got)
	}
}

func TestIsRenderableArtgridResultAcceptsArtlistCanonical(t *testing.T) {
	if !isRenderableArtgridResult(SearchResult{Link: "https://artlist.io/stock-footage/clip/movie-film-moving-slowly-from-a-reel/114756"}) {
		t.Fatal("expected artlist canonical clip URL to be accepted for Artgrid collector")
	}
}

func TestBuildArtgridQueriesIncludesArtlistCanonicalDomain(t *testing.T) {
	queries := buildArtgridQueries("friendly couple")
	found := false
	for _, query := range queries {
		if strings.Contains(query, "site:artlist.io/stock-footage/clip/") {
			found = true
			break
		}
	}
	if !found {
		t.Fatal("expected Artgrid queries to include artlist canonical domain")
	}
}

func TestIsMatchingArtgridClipPageRejectsHomepage(t *testing.T) {
	html := `<html><head><meta property="og:url" content="https://artgrid.io/"><link rel="canonical" href="https://artgrid.io/"></head></html>`
	if isMatchingArtgridClipPage(html, "114756") {
		t.Fatal("expected generic Artgrid homepage HTML to be rejected as a clip page")
	}
}

func TestIsMatchingArtgridClipPageAcceptsBodySignals(t *testing.T) {
	html := `<html><head><title>Night City | Stock Video Footage - Artgrid.io</title></head><body><script>window.__clip="6600269";</script></body></html>`
	if !isMatchingArtgridClipPage(html, "6600269") {
		t.Fatal("expected body/title signal Artgrid HTML to be accepted")
	}
}

func TestLowValueThumbnailDetection(t *testing.T) {
	if !IsLowValueThumbnail("https://example.com/favicon.ico") {
		t.Fatal("expected favicon to be low-value thumbnail")
	}
	if IsLowValueThumbnail("https://i.ytimg.com/vi/abcd1234xyz/hqdefault.jpg") {
		t.Fatal("expected youtube thumbnail to be usable")
	}
}

func TestGoogleVideoCollectorPrefersYouTubeDerivedThumbnail(t *testing.T) {
	result := googleVideoCollector{}.Enrich(nil, SearchResult{
		Link:         "https://www.youtube.com/watch?v=dQw4w9WgXcQ",
		ThumbnailURL: "https://example.com/some-search-thumb.jpg",
	})
	if result.ThumbnailURL != "https://i.ytimg.com/vi/dQw4w9WgXcQ/hqdefault.jpg" {
		t.Fatalf("expected derived youtube thumbnail, got %q", result.ThumbnailURL)
	}
}

func TestGeminiCandidateLimitNeverExceedsCandidates(t *testing.T) {
	if got := GeminiCandidateLimit(9); got != 9 {
		t.Fatalf("expected Gemini limit to stay within candidate count, got %d", got)
	}
}

func TestLimitCollectorQueriesUsesSmallerBudgetForMissingPass(t *testing.T) {
	queries := []string{"a", "b", "c", "d"}

	got := limitCollectorQueries("Artgrid", queries, true)
	if len(got) != 4 {
		t.Fatalf("expected 4 queries for missing-pass Artgrid collector, got %d", len(got))
	}

	got = limitCollectorQueries("Google Video", queries, false)
	if len(got) != 4 {
		t.Fatalf("expected 4 queries for Google Video collector, got %d", len(got))
	}
}

func TestSearchServiceFetchCacheRoundTrip(t *testing.T) {
	service := NewSearchService("http://example.com", "", "")
	service.setCachedFetchResult("html\nhttps://example.com/item", "<html></html>", time.Minute)

	body, ok := service.getCachedFetchResult("html\nhttps://example.com/item")
	if !ok {
		t.Fatal("expected cached fetch result")
	}
	if body != "<html></html>" {
		t.Fatalf("unexpected cached body: %q", body)
	}
}

func TestSplitSearchDeadlinesReservesEnrichmentWindow(t *testing.T) {
	deadline := time.Now().Add(20 * time.Second)
	collectionDeadline, enrichmentDeadline := splitSearchDeadlines(deadline)

	if enrichmentDeadline.IsZero() {
		t.Fatal("expected enrichment deadline to be preserved")
	}
	if !collectionDeadline.Before(enrichmentDeadline) {
		t.Fatalf("expected collection deadline before enrichment deadline, got %v >= %v", collectionDeadline, enrichmentDeadline)
	}
	if gap := enrichmentDeadline.Sub(collectionDeadline); gap < searchEnrichmentReserve-500*time.Millisecond {
		t.Fatalf("expected reserve close to %v, got %v", searchEnrichmentReserve, gap)
	}
}

func TestSplitSearchDeadlinesDoesNotReserveWhenDeadlineIsTooClose(t *testing.T) {
	deadline := time.Now().Add(2 * time.Second)
	collectionDeadline, enrichmentDeadline := splitSearchDeadlines(deadline)

	if !collectionDeadline.Equal(enrichmentDeadline) {
		t.Fatalf("expected identical deadlines when budget is too tight, got %v and %v", collectionDeadline, enrichmentDeadline)
	}
}

func TestSearchServiceSkipsArtgridAPIAfter403(t *testing.T) {
	var apiRequests atomic.Int32
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case strings.HasPrefix(r.URL.Path, "/api/clip/details"):
			apiRequests.Add(1)
			http.Error(w, "forbidden", http.StatusForbidden)
		case strings.HasPrefix(r.URL.Path, "/clip/114756/"):
			w.Header().Set("Content-Type", "text/html; charset=utf-8")
			_, _ = fmt.Fprintf(w, `<html><head><title>Friendly Couple | Stock Video Footage - Artgrid.io</title><meta property="og:title" content="Friendly Couple"><meta property="og:description" content="A warm couple moment"></head><body><script>window.__clip="%s";</script></body></html>`, "114756")
		default:
			http.NotFound(w, r)
		}
	}))
	defer server.Close()

	service := NewSearchService(server.URL, "", "")
	serverURL, err := url.Parse(server.URL)
	if err != nil {
		t.Fatalf("failed to parse test server url: %v", err)
	}
	service.Client = &http.Client{
		Transport: roundTripperFunc(func(req *http.Request) (*http.Response, error) {
			clone := req.Clone(req.Context())
			if clone.URL.Host == "artgrid.io" {
				clone.URL.Scheme = serverURL.Scheme
				clone.URL.Host = serverURL.Host
				clone.Host = serverURL.Host
			}
			return http.DefaultTransport.RoundTrip(clone)
		}),
	}

	item := SearchResult{
		Link:   "https://artgrid.io/clip/114756/friendly-couple",
		Source: "Artgrid",
	}

	first := service.enrichArtgrid(item)
	second := service.enrichArtgrid(item)

	if apiRequests.Load() != 1 {
		t.Fatalf("expected artgrid API to be skipped after first 403, got %d requests", apiRequests.Load())
	}
	if first.Title == "" || second.Title == "" {
		t.Fatalf("expected HTML fallback enrichment to preserve title, got %#v %#v", first, second)
	}
}

type roundTripperFunc func(*http.Request) (*http.Response, error)

func (fn roundTripperFunc) RoundTrip(req *http.Request) (*http.Response, error) {
	return fn(req)
}