package e2e

import (
	"bytes"
	"context"
	"path/filepath"
	"testing"
	"time"

	"github.com/disintegration/imaging"
	"github.com/gen2brain/webp"

	"galo/internal/albums"
	"galo/internal/photos"
)

// TestEffectsEdit covers the effects round trip: the parameters are stored in
// the photo metadata, the background worker renders the edited version, the
// saved parameters carry the normalized effects, a reset removes everything,
// and re-rendering the same edit (including grain) is deterministic.
func TestEffectsEdit(t *testing.T) {
	ctx := context.Background()
	st, closeDB := openStack(t, filepath.Join(t.TempDir(), "galo.db"), t.TempDir())
	defer closeDB()

	user, _, err := st.auth.Register(ctx, "effects@test.local", "", "password123", "E")
	if err != nil {
		t.Fatalf("register: %v", err)
	}
	album, err := st.albums.Create(ctx, user.ID, albums.CreateInput{Title: "Effects"})
	if err != nil {
		t.Fatalf("create album: %v", err)
	}
	p, err := st.photos.Upload(ctx, photos.UploadInput{
		AlbumID: album.ID, UserID: user.ID, Filename: "e.png", Data: makePNG(t),
	})
	if err != nil {
		t.Fatalf("upload: %v", err)
	}

	w := photos.NewWorker(st.photos, time.Second, 10, time.Minute, 2)
	w.ProcessOnce(ctx)

	params := photos.EditParams{Effects: photos.EffectsParams{
		Texture: 25,
		Clarity: 20,
		Dehaze:  15,
		Vignette: photos.VignetteParams{
			Mode: photos.VignetteColor, Amount: 40, Midpoint: 60, Feather: 40, Color: "#ff8800",
		},
		Grain: photos.GrainParams{Amount: 35, Size: 30, Roughness: 60},
	}}
	edited, err := st.photos.EditPhoto(ctx, p.ID, user.ID, params)
	if err != nil {
		t.Fatalf("edit: %v", err)
	}
	if edited.EditParams == nil {
		t.Fatal("edit returned no parameters")
	}
	if _, ok := edited.EditParams["effects"]; !ok {
		t.Fatalf("effects params not returned: %+v", edited.EditParams)
	}

	w.ProcessOnce(ctx)
	got, err := st.photos.Get(ctx, p.ID, user.ID)
	if err != nil {
		t.Fatalf("get: %v", err)
	}
	if got.EditPreviewURL == "" {
		t.Fatalf("no edited preview url: %+v", got)
	}
	if got.EditPreviewKey == "" {
		t.Fatalf("no edited preview key: %+v", got)
	}
	effects, ok := got.EditParams["effects"].(map[string]any)
	if !ok {
		t.Fatalf("effects params not stored: %+v", got.EditParams)
	}
	vignette, ok := effects["vignette"].(map[string]any)
	if !ok {
		t.Fatalf("vignette params not stored: %+v", effects)
	}
	if vignette["mode"] != photos.VignetteColor {
		t.Fatalf("vignette mode = %v, want %q", vignette["mode"], photos.VignetteColor)
	}
	if vignette["color"] != "#ff8800" {
		t.Fatalf("vignette color = %v, want #ff8800", vignette["color"])
	}
	if vignette["midpoint"] != float64(60) {
		t.Fatalf("vignette midpoint = %v, want 60", vignette["midpoint"])
	}
	grain, ok := effects["grain"].(map[string]any)
	if !ok {
		t.Fatalf("grain params not stored: %+v", effects)
	}
	if grain["size"] != float64(30) || grain["roughness"] != float64(60) {
		t.Fatalf("grain params = %+v, want size 30 roughness 60", grain)
	}
	first := previewPixels(t, st, got.EditPreviewKey)

	reset, err := st.photos.ResetEdit(ctx, p.ID, user.ID)
	if err != nil {
		t.Fatalf("reset: %v", err)
	}
	if len(reset.EditParams) != 0 {
		t.Fatalf("reset kept params: %+v", reset.EditParams)
	}
	if reset.EditURL != "" || reset.EditPreviewURL != "" || reset.EditPreviewKey != "" {
		t.Fatalf("reset kept the edited version: %+v", reset)
	}

	// The same parameters and the same photo id must render the same grain.
	if _, err := st.photos.EditPhoto(ctx, p.ID, user.ID, params); err != nil {
		t.Fatalf("edit again: %v", err)
	}
	w.ProcessOnce(ctx)
	again, err := st.photos.Get(ctx, p.ID, user.ID)
	if err != nil {
		t.Fatalf("get after second edit: %v", err)
	}
	if again.EditPreviewURL == "" || again.EditPreviewKey == "" {
		t.Fatalf("no edited preview after second edit: %+v", again)
	}
	second := previewPixels(t, st, again.EditPreviewKey)
	if !bytes.Equal(first, second) {
		t.Fatal("repeated render with the same grain parameters is not deterministic")
	}
}

// previewPixels decodes an edited preview object into its pixel bytes.
func previewPixels(t *testing.T, st *stack, key string) []uint8 {
	t.Helper()
	data, err := st.storage.Get(context.Background(), key)
	if err != nil {
		t.Fatalf("read preview object: %v", err)
	}
	img, err := webp.Decode(bytes.NewReader(data))
	if err != nil {
		t.Fatalf("decode preview: %v", err)
	}
	return imaging.Clone(img).Pix
}