package server

import (
	"database/sql"
	"html"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"strings"
	"testing"

	"vidarchive/internal/config"
	"vidarchive/internal/database"
	"vidarchive/internal/handler"
	"vidarchive/internal/repository"
	"vidarchive/internal/service"
	"vidarchive/internal/worker"
)

func setupTestServer(t *testing.T) (*Server, *config.Config, func()) {
	srv, cfg, _, cleanup := setupTestServerDB(t)
	return srv, cfg, cleanup
}

// setupTestServerDB is setupTestServer with the database handle exposed, for
// tests that need to break the database on purpose.
func setupTestServerDB(t *testing.T) (*Server, *config.Config, *sql.DB, func()) {
	t.Helper()
	dataDir := t.TempDir()
	t.Setenv("VIDARCHIVE_DATA_DIR", dataDir)

	cfg := config.New()
	if err := os.MkdirAll(cfg.LibraryDir, 0o755); err != nil {
		t.Fatalf("create library dir: %v", err)
	}
	if err := os.MkdirAll(cfg.TempDir, 0o755); err != nil {
		t.Fatalf("create temp dir: %v", err)
	}

	db, err := database.New(cfg)
	if err != nil {
		t.Fatalf("init db: %v", err)
	}

	presetRepo := repository.NewPresetRepository(db)
	downloadRepo := repository.NewDownloadRepository(db)
	settingsRepo := repository.NewSettingsRepository(db)
	subscriptionRepo := repository.NewSubscriptionRepository(db)

	presetSvc := service.NewPresetService(presetRepo)
	librarySvc := service.NewLibraryService(cfg.LibraryDir, cfg.FFmpegPath, cfg.FFprobePath)
	settingsSvc := service.NewSettingsService(settingsRepo)
	subscriptionSvc := service.NewSubscriptionService(subscriptionRepo, cfg)
	downloadSvc := service.NewDownloadService(downloadRepo, librarySvc, presetSvc, settingsSvc, subscriptionSvc, cfg)
	workerPool := worker.New(downloadSvc, cfg.Workers)

	h, err := handler.New(cfg, presetSvc, downloadSvc, librarySvc, settingsSvc, subscriptionSvc, workerPool)
	if err != nil {
		t.Fatalf("init handler: %v", err)
	}

	srv := New(cfg, h)
	cleanup := func() {
		workerPool.Stop()
		db.Close()
	}
	return srv, cfg, db, cleanup
}

func createItem(t *testing.T, libraryDir, relPath, name string, files map[string]string) {
	t.Helper()
	itemDir := filepath.Join(libraryDir, relPath)
	if err := os.MkdirAll(itemDir, 0o755); err != nil {
		t.Fatalf("create item dir: %v", err)
	}
	marker := filepath.Join(itemDir, ".vidarchive-item.toml")
	if err := os.WriteFile(marker, []byte("name = \""+name+"\"\nduration = -1\n"), 0o644); err != nil {
		t.Fatalf("write marker: %v", err)
	}
	for filename, content := range files {
		path := filepath.Join(itemDir, filename)
		if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
			t.Fatalf("write file %s: %v", filename, err)
		}
	}
}

func TestLibraryEngagementViews(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "engagement", "Engagement", map[string]string{
		"video.mp4": "dummy video",
		"info.json": `{"comments":[{"id":"parent","author":"<parent>","text":"safe <comment>","time_text":"today"},{"id":"reply","parent":"parent","author":"<child>","text":"reply","time_text":"today"}],"heatmap":[{"start_time":0,"end_time":10,"value":1}]}`,
	})

	detail := getWith(srv.Router(), "/library/item/engagement", nil)
	if detail.Code != http.StatusOK {
		t.Fatalf("detail status = %d", detail.Code)
	}
	body := detail.Body.String()
	for _, want := range []string{"Playback heatmap", "&lt;parent&gt;", "&lt;child&gt;", "safe &lt;comment&gt;", "replying to <strong>&lt;parent&gt;</strong>", "View all comments"} {
		if !strings.Contains(body, want) {
			t.Errorf("detail missing %q", want)
		}
	}

	all := getWith(srv.Router(), "/library/comments/engagement", nil)
	if all.Code != http.StatusOK || !strings.Contains(all.Body.String(), "Engagement comments") {
		t.Fatalf("comments view status/body unexpected: %d %s", all.Code, all.Body.String())
	}

	// A real item whose path ends in "comments" must remain reachable through
	// the item route now that the full comments view has its own namespace.
	createItem(t, cfg.LibraryDir, "playlist/comments", "Nested Comments Item", map[string]string{
		"video.mp4": "dummy video",
	})
	item := getWith(srv.Router(), "/library/item/playlist/comments", nil)
	if item.Code != http.StatusOK || !strings.Contains(item.Body.String(), "Nested Comments Item") {
		t.Fatalf("item path ending in comments was shadowed: %d %s", item.Code, item.Body.String())
	}
}

func TestCommentsViewMalformedSidecarIsError(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "bad-comments", "Bad comments", map[string]string{
		"video.mp4": "dummy video",
		"info.json": `{"comments":[`,
	})
	w := getWith(srv.Router(), "/library/comments/bad-comments", nil)
	if w.Code != http.StatusInternalServerError {
		t.Fatalf("malformed comments status = %d, want 500", w.Code)
	}
	if !strings.Contains(w.Body.String(), "Something went wrong") {
		t.Fatalf("malformed comments response = %q", w.Body.String())
	}
}

func TestCommentsViewEncodedPath(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	const item = "nested/An Item +"
	createItem(t, cfg.LibraryDir, item, "Encoded comments", map[string]string{
		"video.mp4": "dummy video",
		"info.json": `{"comments":[{"author":"author","text":"hello"}]}`,
	})

	reqURL := "/library/comments/" + (&url.URL{Path: item}).EscapedPath()
	w := getWith(srv.Router(), reqURL, nil)
	if w.Code != http.StatusOK || !strings.Contains(w.Body.String(), "Encoded comments") {
		t.Fatalf("encoded comments route %s: status=%d body=%s", reqURL, w.Code, w.Body.String())
	}
}

func TestNestedLibraryItem(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "test/My Item [id]", "My Item", map[string]string{
		"My Item [id].mp4": "dummy video",
	})

	router := srv.Router()

	req := httptest.NewRequest("GET", "/library/item/test/My%20Item%20%5Bid%5D", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		body, _ := io.ReadAll(w.Body)
		t.Errorf("expected 200, got %d: %s", w.Code, string(body))
	}
}

// A directory whose name contains a literal '+' must round-trip: in a URL path
// '+' is a literal plus (not a space), reachable raw or percent-encoded.
func TestLiteralPlusInPathSegment(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "C++ Tutorial", "C++ Tutorial", map[string]string{
		"C++ Tutorial.mp4": "dummy video",
	})

	router := srv.Router()
	for _, path := range []string{
		"/library/item/C++%20Tutorial",
		"/library/item/C%2B%2B%20Tutorial",
	} {
		req := httptest.NewRequest("GET", path, nil)
		w := httptest.NewRecorder()
		router.ServeHTTP(w, req)
		if w.Code != http.StatusOK {
			body, _ := io.ReadAll(w.Body)
			t.Errorf("%s: expected 200, got %d: %s", path, w.Code, string(body))
		}
	}
}

func TestMediaFileQueryDecoding(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "My Item [id]", "My Item", map[string]string{
		"My Item [id].mp4": "dummy video",
		"My+Other.mp4":     "dummy video plus",
	})

	router := srv.Router()

	tests := []struct {
		path     string
		expected int
	}{
		{"/media/item/My%20Item%20%5Bid%5D?file=My+Item+%5Bid%5D.mp4", http.StatusOK},
		{"/media/item/My%20Item%20%5Bid%5D?file=My%20Item%20%5Bid%5D.mp4", http.StatusOK},
		{"/media/item/My%20Item%20%5Bid%5D?file=My%2BOther.mp4", http.StatusOK},
		{"/media/item/My%20Item%20%5Bid%5D?file=missing.mp4", http.StatusNotFound},
	}
	for _, tc := range tests {
		req := httptest.NewRequest("GET", tc.path, nil)
		w := httptest.NewRecorder()
		router.ServeHTTP(w, req)
		if w.Code != tc.expected {
			body, _ := io.ReadAll(w.Body)
			t.Errorf("%s: expected %d, got %d: %s", tc.path, tc.expected, w.Code, string(body))
		}
	}
}

// TestSubtitleServedByPathSegment guards the regression where subtitle tracks
// are linked as <item>/subtitles/<lang> (language as a trailing path segment),
// but the handler only recognized the "/subtitles" suffix with a ?lang= query.
// The path form fell through to media serving and returned 400 "Missing file".
func TestSubtitleServedByPathSegment(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	// An item whose name contains non-ASCII + spaces, like the reported URL.
	const item = "ずんだパーリナイ ⧸ なみぐる [ywXQ9SqsaBQ]"
	createItem(t, cfg.LibraryDir, item, "Vid", map[string]string{
		"video.mp4": "dummy video",
	})
	vtt := "WEBVTT\n\n00:00:00.000 --> 00:00:01.000\nhi\n"
	subDir := filepath.Join(cfg.LibraryDir, item, "subtitles")
	if err := os.MkdirAll(subDir, 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(subDir, "eng.vtt"), []byte(vtt), 0o644); err != nil {
		t.Fatal(err)
	}

	router := srv.Router()
	reqURL := "/media/item/" + (&url.URL{Path: item}).EscapedPath() + "/subtitles/eng"
	req := httptest.NewRequest("GET", reqURL, nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		body, _ := io.ReadAll(w.Body)
		t.Fatalf("expected 200 for %s, got %d: %s", reqURL, w.Code, string(body))
	}
	if ct := w.Header().Get("Content-Type"); !strings.HasPrefix(ct, "text/vtt") {
		t.Errorf("expected text/vtt content-type, got %q", ct)
	}
	if body, _ := io.ReadAll(w.Body); !strings.Contains(string(body), "WEBVTT") {
		t.Errorf("expected the .vtt contents, got %q", string(body))
	}

	// A traversal attempt in the language segment must be rejected, not served.
	bad := httptest.NewRequest("GET", "/media/item/"+(&url.URL{Path: item}).EscapedPath()+"/subtitles/..%2f..%2fsecret", nil)
	bw := httptest.NewRecorder()
	router.ServeHTTP(bw, bad)
	if bw.Code == http.StatusOK {
		t.Errorf("traversal in language segment was served (status %d)", bw.Code)
	}
}

func TestPathTraversalBlocked(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	outside := filepath.Join(cfg.DataDir, "secret")
	if err := os.MkdirAll(outside, 0o755); err != nil {
		t.Fatalf("create outside dir: %v", err)
	}
	marker := filepath.Join(outside, ".vidarchive-item.toml")
	if err := os.WriteFile(marker, []byte("name = \"secret\"\nduration = -1\n"), 0o644); err != nil {
		t.Fatalf("write marker: %v", err)
	}

	router := srv.Router()

	req := httptest.NewRequest("GET", "/library/item/../secret", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusNotFound {
		t.Errorf("expected 404 for path traversal, got %d", w.Code)
	}
}

func TestPerFileExistingThumbnailServed(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	// A pre-existing per-file thumbnail (<stem>.thumbnail.webp) is served for the
	// matching ?file= request without re-extraction.
	createItem(t, cfg.LibraryDir, "thumb-item", "Thumb Item", map[string]string{
		"video.mp4":            "dummy video",
		"video.thumbnail.webp": "GENERATED-THUMB",
	})

	router := srv.Router()
	req := httptest.NewRequest("GET", "/media/item/thumb-item/thumbnail?file=video.mp4", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		body, _ := io.ReadAll(w.Body)
		t.Fatalf("expected 200, got %d: %s", w.Code, string(body))
	}
	if body, _ := io.ReadAll(w.Body); string(body) != "GENERATED-THUMB" {
		t.Errorf("expected the existing per-file thumbnail, got %q", string(body))
	}
}

func TestAudioThumbnailPlaceholder(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "audio-item", "Audio Item", map[string]string{
		"song.mp3": "dummy audio",
	})

	router := srv.Router()
	req := httptest.NewRequest("GET", "/media/item/audio-item/thumbnail", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		body, _ := io.ReadAll(w.Body)
		t.Fatalf("expected 200, got %d: %s", w.Code, string(body))
	}
	body, _ := io.ReadAll(w.Body)
	if len(body) == 0 {
		t.Errorf("placeholder thumbnail body was empty")
	}
}

func TestMultiFileCardThumbnailURLsDecodeToFilenames(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	// Filenames with spaces are the case that broke: the template must emit a
	// query value that the handler decodes back to the exact filename (the bug
	// was double-escaping spaces to %2b, which decodes to '+').
	files := map[string]string{
		"01 - Color Bars.mp4":   "v",
		"02 - Test Pattern.mp4": "v",
	}
	createItem(t, cfg.LibraryDir, "multi", "Multi", files)

	req := httptest.NewRequest("GET", "/library", nil)
	w := httptest.NewRecorder()
	srv.Router().ServeHTTP(w, req)
	body, _ := io.ReadAll(w.Body)

	re := regexp.MustCompile(`thumbnail\?file=([^"]+)`)
	matches := re.FindAllStringSubmatch(string(body), -1)
	if len(matches) != len(files) {
		t.Fatalf("expected %d per-file thumbnail URLs in the card, got %d", len(files), len(matches))
	}
	for _, m := range matches {
		vals, err := url.ParseQuery("file=" + m[1])
		if err != nil {
			t.Fatalf("bad query %q: %v", m[1], err)
		}
		got := vals.Get("file")
		if _, ok := files[got]; !ok {
			t.Errorf("thumbnail file=%q decodes to %q, which is not a real filename (double-encoding regression)", m[1], got)
		}
	}
}

// TestNestedFolderLinkRoundTrip guards the double-encoding regression: a folder
// whose name contains a space was linked with urlEncodePath *inside* a ?path=
// query, which html/template then re-escaped (%20 -> %2520). Clicking the link
// landed on a path the server decoded to "playlist%20test%202" — a directory
// that doesn't exist — so the folder rendered empty and the breadcrumb showed
// the literal "%20". The link must round-trip: its decoded ?path must be the
// real directory, the item inside must render, and the breadcrumb must show the
// human-readable name.
func TestNestedFolderLinkRoundTrip(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "subs/playlist test 2/Vid One", "Vid One", map[string]string{
		"video.mp4": "dummy video",
	})
	router := srv.Router()

	// List the parent and pull out the generated folder link.
	req := httptest.NewRequest("GET", "/library?path=subs", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Fatalf("list /library?path=subs: got %d", w.Code)
	}
	body := w.Body.String()

	folderHref := regexp.MustCompile(`href="(/library\?path=[^"]+)" class="folder-item"`).FindStringSubmatch(body)
	if folderHref == nil {
		t.Fatalf("no folder link rendered for nested folder; body:\n%s", body)
	}
	href := html.UnescapeString(folderHref[1])

	// The link's decoded ?path must be the real directory, not a still-encoded one.
	u, err := url.Parse(href)
	if err != nil {
		t.Fatalf("parse folder href %q: %v", href, err)
	}
	if got := u.Query().Get("path"); got != "subs/playlist test 2" {
		t.Fatalf("folder link path decodes to %q, want %q (double-encoding regression)", got, "subs/playlist test 2")
	}

	// Follow the link exactly as a browser would. The folder must not be empty,
	// and the breadcrumb must show the readable name (never the encoded form).
	req = httptest.NewRequest("GET", href, nil)
	w = httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Fatalf("follow folder link %q: got %d", href, w.Code)
	}
	nested := w.Body.String()
	if !strings.Contains(nested, "Vid One") {
		t.Errorf("nested folder rendered empty — item 'Vid One' missing; body:\n%s", nested)
	}
	// The breadcrumb must display the readable name, not the percent-encoded form.
	if !strings.Contains(nested, ">playlist test 2<") {
		t.Errorf("breadcrumb missing readable folder name 'playlist test 2'")
	}
	if strings.Contains(nested, ">playlist%20test%202<") {
		t.Errorf("breadcrumb displays the encoded name instead of a space (regression)")
	}
	// No link may carry a double-encoded path (%2520 == %25 + 20 == re-escaped %20).
	if strings.Contains(nested, "%2520") {
		t.Errorf("a link is double-encoded (%%2520) — urlEncodePath inside a ?path= query (regression)")
	}
}

func TestListingDoesNotExtractThumbnails(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "novid", "No Thumb", map[string]string{
		"video.mp4": "dummy video",
	})

	router := srv.Router()
	req := httptest.NewRequest("GET", "/library", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d", w.Code)
	}

	// Rendering the listing must not have created any thumbnail file.
	entries, err := os.ReadDir(filepath.Join(cfg.LibraryDir, "novid"))
	if err != nil {
		t.Fatal(err)
	}
	for _, e := range entries {
		if strings.Contains(e.Name(), ".thumbnail.") {
			t.Errorf("listing extracted a thumbnail (%q) — should happen on request only", e.Name())
		}
	}
}

func TestGeneratedThumbnailServedOverIcon(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	createItem(t, cfg.LibraryDir, "gen", "Gen", map[string]string{
		"video.mp4":            "dummy video",
		"video.thumbnail.webp": "WEBPDATA",
	})

	router := srv.Router()
	req := httptest.NewRequest("GET", "/media/item/gen/thumbnail?file=video.mp4", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d", w.Code)
	}
	if body, _ := io.ReadAll(w.Body); string(body) != "WEBPDATA" {
		t.Errorf("expected generated thumbnail contents, got %q", string(body))
	}
}

func TestThumbnailExtractedOnRequest(t *testing.T) {
	if _, err := exec.LookPath("ffmpeg"); err != nil {
		t.Skip("ffmpeg not on PATH")
	}
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	itemDir := filepath.Join(cfg.LibraryDir, "realvid")
	createItem(t, cfg.LibraryDir, "realvid", "Real", nil)
	cmd := exec.Command("ffmpeg", "-hide_banner", "-loglevel", "error",
		"-f", "lavfi", "-i", "testsrc=duration=3:size=64x64:rate=5",
		"-pix_fmt", "yuv420p", filepath.Join(itemDir, "realvid.mp4"), "-y")
	if out, err := cmd.CombinedOutput(); err != nil {
		t.Fatalf("make test video: %v\n%s", err, out)
	}

	router := srv.Router()
	req := httptest.NewRequest("GET", "/media/item/realvid/thumbnail?file=realvid.mp4", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d", w.Code)
	}
	if ct := w.Header().Get("Content-Type"); !strings.HasPrefix(ct, "image/") {
		t.Errorf("expected image content-type, got %q", ct)
	}
	body, _ := io.ReadAll(w.Body)
	if len(body) == 0 {
		t.Error("served thumbnail body was empty")
	}

	// A real thumbnail file should now exist on disk, with no temp leftovers.
	entries, _ := os.ReadDir(itemDir)
	var found bool
	for _, e := range entries {
		if strings.Contains(e.Name(), ".thumbnail.") {
			found = true
		}
		if strings.Contains(e.Name(), ".tmp") {
			t.Errorf("leftover temp file %q", e.Name())
		}
	}
	if !found {
		t.Error("no thumbnail file written to disk after request")
	}
}

func TestLibraryPageIsFast(t *testing.T) {
	srv, cfg, cleanup := setupTestServer(t)
	defer cleanup()

	for i := 0; i < 50; i++ {
		createItem(t, cfg.LibraryDir, "item-"+string(rune('a'+i)), "Item", map[string]string{
			"video.mp4": "dummy",
		})
	}

	router := srv.Router()
	req := httptest.NewRequest("GET", "/library", nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	if w.Code != http.StatusOK {
		body, _ := io.ReadAll(w.Body)
		t.Fatalf("expected 200, got %d: %s", w.Code, string(body))
	}
}