package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"bookmarkmanager/backend/internal/store"
)

const testToken = "s3cret-token"

func testConfig() Config {
	return Config{
		Token:          testToken,
		AllowedOrigins: []string{"https://asuracomic.net", "https://demonicscans.org"},
		Port:           "8080",
	}
}

func newTestServer(t *testing.T) http.Handler {
	t.Helper()
	dbPath := filepath.Join(t.TempDir(), "test.db")
	s, err := store.Open(dbPath)
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { s.Close() })
	return newRouter(s, testConfig())
}

func auth(req *http.Request) *http.Request {
	req.Header.Set("Authorization", "Bearer "+testToken)
	return req
}

func floatPtr(f float64) *float64 { return &f }

// seedForCheck inserts a bookmark and forces its latest_checked_at.
func seedForCheck(t *testing.T, s *store.Store, key, seriesURL string, checkedAt int64) {
	t.Helper()
	if _, err := s.Upsert(store.Bookmark{
		Key:       key,
		Site:      "asura",
		SeriesID:  key,
		SeriesURL: seriesURL,
		UpdatedAt: 1000,
	}); err != nil {
		t.Fatalf("seed %q: %v", key, err)
	}
	if err := s.MarkLatestChecked(key, checkedAt); err != nil {
		t.Fatalf("seed mark %q: %v", key, err)
	}
}

func readLatestCheckedAt(t *testing.T, s *store.Store, key string) int64 {
	t.Helper()
	ts, err := s.LatestCheckedAt(key)
	if err != nil {
		t.Fatalf("LatestCheckedAt %q: %v", key, err)
	}
	return ts
}

func TestHealthzNoAuth(t *testing.T) {
	srv := newTestServer(t)
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, httptest.NewRequest(http.MethodGet, "/healthz", nil))
	if rr.Code != http.StatusOK {
		t.Fatalf("healthz status = %d, want 200", rr.Code)
	}
	if rr.Body.String() != "ok" {
		t.Fatalf("healthz body = %q, want ok", rr.Body.String())
	}
}

func TestAuthRequired(t *testing.T) {
	srv := newTestServer(t)
	cases := []struct {
		name   string
		header string
	}{
		{"no header", ""},
		{"bad token", "Bearer wrong"},
		{"not bearer", "Basic " + testToken},
		{"empty bearer", "Bearer "},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			req := httptest.NewRequest(http.MethodGet, "/bookmarks", nil)
			if tc.header != "" {
				req.Header.Set("Authorization", tc.header)
			}
			rr := httptest.NewRecorder()
			srv.ServeHTTP(rr, req)
			if rr.Code != http.StatusUnauthorized {
				t.Fatalf("status = %d, want 401", rr.Code)
			}
		})
	}
}

func TestAuthAccepted(t *testing.T) {
	srv := newTestServer(t)
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodGet, "/bookmarks", nil)))
	if rr.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rr.Code)
	}
	if got := rr.Body.String(); got != "[]\n" {
		t.Fatalf("empty list body = %q, want []", got)
	}
}

func TestCORSPreflight(t *testing.T) {
	srv := newTestServer(t)
	req := httptest.NewRequest(http.MethodOptions, "/bookmarks/asura:foo-1", nil)
	req.Header.Set("Origin", "https://asuracomic.net")
	req.Header.Set("Access-Control-Request-Method", "PUT")
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, req)

	if rr.Code != http.StatusNoContent {
		t.Fatalf("preflight status = %d, want 204", rr.Code)
	}
	if got := rr.Header().Get("Access-Control-Allow-Origin"); got != "https://asuracomic.net" {
		t.Fatalf("Allow-Origin = %q, want reflected origin", got)
	}
	if got := rr.Header().Get("Access-Control-Allow-Methods"); got == "" {
		t.Fatal("Allow-Methods missing")
	}
	if got := rr.Header().Get("Access-Control-Allow-Headers"); got == "" {
		t.Fatal("Allow-Headers missing")
	}
}

func TestCORSDisallowedOrigin(t *testing.T) {
	srv := newTestServer(t)
	req := httptest.NewRequest(http.MethodOptions, "/bookmarks", nil)
	req.Header.Set("Origin", "https://evil.example")
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, req)
	if got := rr.Header().Get("Access-Control-Allow-Origin"); got != "" {
		t.Fatalf("Allow-Origin = %q, want empty for disallowed origin", got)
	}
}

func TestBookmarkRoundTrip(t *testing.T) {
	srv := newTestServer(t)
	key := "asura:solo-leveling-123"
	in := store.Bookmark{
		Title:          "Solo Leveling",
		SeriesURL:      "https://asuracomic.net/series/solo-leveling-123",
		Cover:          "https://asuracomic.net/cover.jpg",
		LastChapter:    "Chapter 10",
		LastChapterNum: 10,
		LastChapterURL: "https://asuracomic.net/series/solo-leveling-123/chapter/10",
	}
	body, _ := json.Marshal(in)

	// PUT
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodPut, "/bookmarks/"+key, bytes.NewReader(body))))
	if rr.Code != http.StatusOK {
		t.Fatalf("PUT status = %d, want 200", rr.Code)
	}
	var stored store.Bookmark
	if err := json.Unmarshal(rr.Body.Bytes(), &stored); err != nil {
		t.Fatalf("decode PUT response: %v", err)
	}
	if stored.Key != key || stored.Site != "asura" || stored.SeriesID != "solo-leveling-123" {
		t.Fatalf("derived fields wrong: %+v", stored)
	}
	if stored.UpdatedAt == 0 {
		t.Fatal("server did not set updated_at")
	}

	// GET
	rr = httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodGet, "/bookmarks", nil)))
	var list []store.Bookmark
	if err := json.Unmarshal(rr.Body.Bytes(), &list); err != nil {
		t.Fatalf("decode list: %v", err)
	}
	if len(list) != 1 || list[0].Key != key || list[0].LastChapterNum != 10 {
		t.Fatalf("GET list wrong: %+v", list)
	}

	// PUT again (upsert, progress advance)
	in.LastChapter, in.LastChapterNum = "Chapter 11", 11
	body, _ = json.Marshal(in)
	rr = httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodPut, "/bookmarks/"+key, bytes.NewReader(body))))
	if rr.Code != http.StatusOK {
		t.Fatalf("second PUT status = %d", rr.Code)
	}
	rr = httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodGet, "/bookmarks", nil)))
	json.Unmarshal(rr.Body.Bytes(), &list)
	if len(list) != 1 || list[0].LastChapterNum != 11 {
		t.Fatalf("upsert did not update in place: %+v", list)
	}

	// DELETE
	rr = httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodDelete, "/bookmarks/"+key, nil)))
	if rr.Code != http.StatusNoContent {
		t.Fatalf("DELETE status = %d, want 204", rr.Code)
	}
	rr = httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodGet, "/bookmarks", nil)))
	json.Unmarshal(rr.Body.Bytes(), &list)
	if len(list) != 0 {
		t.Fatalf("after delete list = %+v, want empty", list)
	}
}

// putBookmark PUTs b at key and returns the bookmark the server echoes back,
// which is the row as actually stored (not the request payload).
func putBookmark(t *testing.T, srv http.Handler, key string, b store.Bookmark) store.Bookmark {
	t.Helper()
	body, _ := json.Marshal(b)
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodPut, "/bookmarks/"+key, bytes.NewReader(body))))
	if rr.Code != http.StatusOK {
		t.Fatalf("PUT %s status = %d, body = %s", key, rr.Code, rr.Body.String())
	}
	var out store.Bookmark
	if err := json.Unmarshal(rr.Body.Bytes(), &out); err != nil {
		t.Fatalf("decode PUT response: %v", err)
	}
	return out
}

func getBookmarks(t *testing.T, srv http.Handler) []store.Bookmark {
	t.Helper()
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodGet, "/bookmarks", nil)))
	if rr.Code != http.StatusOK {
		t.Fatalf("GET status = %d", rr.Code)
	}
	var list []store.Bookmark
	if err := json.Unmarshal(rr.Body.Bytes(), &list); err != nil {
		t.Fatalf("decode list: %v", err)
	}
	return list
}

// updated_at drives list ordering, so it must move only on a real progress
// advance — never on a favorite toggle or a latest-chapter capture.
func TestUpsertConditionalUpdatedAt(t *testing.T) {
	cases := []struct {
		name       string
		mutate     func(store.Bookmark) store.Bookmark
		wantBumped bool
	}{
		{
			name:       "unchanged progress",
			mutate:     func(b store.Bookmark) store.Bookmark { return b },
			wantBumped: false,
		},
		{
			name: "changed progress",
			mutate: func(b store.Bookmark) store.Bookmark {
				b.LastChapter, b.LastChapterNum = "Chapter 11", 11
				return b
			},
			wantBumped: true,
		},
		{
			name: "favorite only",
			mutate: func(b store.Bookmark) store.Bookmark {
				b.Favorite = true
				return b
			},
			wantBumped: false,
		},
		{
			name: "latest chapter only",
			mutate: func(b store.Bookmark) store.Bookmark {
				b.LatestChapter, b.LatestChapterNum = "Chapter 15", floatPtr(15)
				return b
			},
			wantBumped: false,
		},
		{
			name: "unrelated metadata only",
			mutate: func(b store.Bookmark) store.Bookmark {
				b.Title, b.Cover = "Renamed", "https://example.test/new.jpg"
				return b
			},
			wantBumped: false,
		},
	}

	for i, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			srv := newTestServer(t)
			key := fmt.Sprintf("asura:cond-%d", i)

			first := putBookmark(t, srv, key, store.Bookmark{
				Title:          "Test",
				LastChapter:    "Chapter 10",
				LastChapterNum: 10,
			})
			if first.UpdatedAt == 0 {
				t.Fatal("new bookmark did not get updated_at set")
			}

			// Guarantee a later wall-clock ms so a real bump is observable.
			time.Sleep(2 * time.Millisecond)

			second := putBookmark(t, srv, key, tc.mutate(first))
			if tc.wantBumped && second.UpdatedAt <= first.UpdatedAt {
				t.Fatalf("updated_at = %d, want > %d", second.UpdatedAt, first.UpdatedAt)
			}
			if !tc.wantBumped && second.UpdatedAt != first.UpdatedAt {
				t.Fatalf("updated_at = %d, want preserved %d", second.UpdatedAt, first.UpdatedAt)
			}

			// The PUT response must match what a subsequent GET reports.
			list := getBookmarks(t, srv)
			if len(list) != 1 {
				t.Fatalf("list = %+v, want 1 item", list)
			}
			if list[0].UpdatedAt != second.UpdatedAt {
				t.Fatalf("GET updated_at = %d, PUT echoed %d", list[0].UpdatedAt, second.UpdatedAt)
			}
		})
	}
}

func TestFavoriteRoundTrip(t *testing.T) {
	srv := newTestServer(t)
	key := "demonic:some-series"

	stored := putBookmark(t, srv, key, store.Bookmark{Title: "Fav", Favorite: true})
	if !stored.Favorite {
		t.Fatalf("PUT response favorite = false, want true")
	}

	list := getBookmarks(t, srv)
	if len(list) != 1 || !list[0].Favorite {
		t.Fatalf("favorite did not round-trip: %+v", list)
	}

	// Unfavoriting must persist too (guards against a write that only ever ORs in true).
	stored = putBookmark(t, srv, key, store.Bookmark{Title: "Fav", Favorite: false})
	if stored.Favorite {
		t.Fatal("PUT response favorite = true after unfavorite")
	}
	list = getBookmarks(t, srv)
	if len(list) != 1 || list[0].Favorite {
		t.Fatalf("unfavorite did not round-trip: %+v", list)
	}
}

func TestLatestChapterNullable(t *testing.T) {
	srv := newTestServer(t)
	key := "asura:latest-test"

	// Never captured: latest_chapter_num must serialize as JSON null.
	body, _ := json.Marshal(store.Bookmark{Title: "No latest yet"})
	rr := httptest.NewRecorder()
	srv.ServeHTTP(rr, auth(httptest.NewRequest(http.MethodPut, "/bookmarks/"+key, bytes.NewReader(body))))
	if rr.Code != http.StatusOK {
		t.Fatalf("PUT status = %d", rr.Code)
	}
	if !strings.Contains(rr.Body.String(), `"latest_chapter_num":null`) {
		t.Fatalf("want latest_chapter_num null in response, got %s", rr.Body.String())
	}

	list := getBookmarks(t, srv)
	if len(list) != 1 || list[0].LatestChapterNum != nil {
		t.Fatalf("latest_chapter_num = %v, want nil", list[0].LatestChapterNum)
	}

	// Once captured it round-trips as a value.
	stored := putBookmark(t, srv, key, store.Bookmark{
		Title:            "No latest yet",
		LatestChapter:    "Chapter 162",
		LatestChapterNum: floatPtr(162),
	})
	if stored.LatestChapterNum == nil || *stored.LatestChapterNum != 162 {
		t.Fatalf("PUT response latest_chapter_num = %v, want 162", stored.LatestChapterNum)
	}
	list = getBookmarks(t, srv)
	if len(list) != 1 || list[0].LatestChapterNum == nil || *list[0].LatestChapterNum != 162 {
		t.Fatalf("latest chapter did not round-trip: %+v", list)
	}
	if list[0].LatestChapter != "Chapter 162" {
		t.Fatalf("latest_chapter = %q, want %q", list[0].LatestChapter, "Chapter 162")
	}
}

func TestLoadConfigWebPassword(t *testing.T) {
	t.Setenv("API_TOKEN", "token-abc")
	t.Setenv("WEB_PASSWORD", "hunter2")
	if got := loadConfig().WebPassword; got != "hunter2" {
		t.Fatalf("WebPassword = %q, want hunter2", got)
	}

	t.Setenv("WEB_PASSWORD", "")
	if got := loadConfig().WebPassword; got != "" {
		t.Fatalf("WebPassword = %q with the variable unset, want empty", got)
	}
}

// A userscript PUT body has no latest_checked_at field. If the column is ever
// moved into bookmarkColumns, this test catches it: the PUT would reset the
// cooldown and the poller would re-fetch that series on every single tick.
func TestPutDoesNotClobberLatestCheckedAt(t *testing.T) {
	dbPath := filepath.Join(t.TempDir(), "test.db")
	s, err := store.Open(dbPath)
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { s.Close() })
	srv := newRouter(s, testConfig())

	seedForCheck(t, s, "asura:x", "https://asurascans.com/comics/x", 777)

	// Exactly what the userscript sends: no latest_checked_at key at all.
	body := `{"key":"asura:x","site":"asura","series_id":"x",
		"series_url":"https://asurascans.com/comics/x",
		"last_chapter":"Chapter 5","last_chapter_num":5}`
	req := httptest.NewRequest(http.MethodPut, "/bookmarks/asura:x", strings.NewReader(body))
	req.Header.Set("Authorization", "Bearer "+testToken)
	req.Header.Set("Content-Type", "application/json")
	rec := httptest.NewRecorder()
	srv.ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("PUT status = %d, want 200 (body %s)", rec.Code, rec.Body.String())
	}
	if got := readLatestCheckedAt(t, s, "asura:x"); got != 777 {
		t.Fatalf("latest_checked_at = %d after client PUT, want 777 preserved", got)
	}
}

// The userscript route is registered outside the `if cfg.WebPassword != ""`
// block in newRouter, so it must keep working on a deployment that never set
// WEB_PASSWORD — see internal/userscript for the handler's own behaviour.
func TestUserscriptServedWithWebUIDisabled(t *testing.T) {
	path := filepath.Join(t.TempDir(), "manga-bookmark.user.js")
	if err := os.WriteFile(path, []byte("console.log(1);\n"), 0o644); err != nil {
		t.Fatalf("write script: %v", err)
	}

	dbPath := filepath.Join(t.TempDir(), "nopass.db")
	s, err := store.Open(dbPath)
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { s.Close() })
	cfg := testConfig() // WebPassword empty
	cfg.UserscriptPath = path

	rr := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet, "/u/"+testToken+"/manga-bookmark.user.js", nil)
	newRouter(s, cfg).ServeHTTP(rr, req)
	if rr.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rr.Code)
	}
}