package api

import (
	"bytes"
	"context"
	"image"
	"image/png"
	"mime/multipart"
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/gin-gonic/gin"

	"gitea.stevedudenhoeffer.com/steve/pansy/internal/config"
	"gitea.stevedudenhoeffer.com/steve/pansy/internal/service"
	"gitea.stevedudenhoeffer.com/steve/pansy/internal/store"
	"gitea.stevedudenhoeffer.com/steve/pansy/internal/vision"
)

// packetEngine builds an engine whose service reads seed packets via the given
// canned extractor, so the scan endpoint can be tested without a live model.
func packetEngine(t *testing.T, cfg *config.Config, extract func() (vision.SeedPacket, error)) *gin.Engine {
	t.Helper()
	gin.SetMode(gin.TestMode)
	db, err := store.Open(":memory:")
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { db.Close() })
	if err := db.Migrate(context.Background()); err != nil {
		t.Fatalf("Migrate: %v", err)
	}
	svc := service.New(db, cfg, service.WithPacketExtractor(
		func(context.Context, string, string, []byte) (vision.SeedPacket, error) { return extract() },
	))
	return New(cfg, svc)
}

// visionCfg is a config with a vision model + key configured, so packet scanning
// is available.
func visionCfg() *config.Config {
	c := localCfg()
	c.Agent = config.AgentConfig{OllamaCloudAPIKey: "k", VisionModel: "ollama-cloud/vision:cloud"}
	return c
}

// pngUpload builds a multipart body with a real PNG under the "image" field.
func pngUpload(t *testing.T) (body *bytes.Buffer, contentType string) {
	t.Helper()
	var img bytes.Buffer
	if err := png.Encode(&img, image.NewRGBA(image.Rect(0, 0, 32, 24))); err != nil {
		t.Fatalf("encode png: %v", err)
	}
	var buf bytes.Buffer
	w := multipart.NewWriter(&buf)
	part, err := w.CreateFormFile("image", "packet.png")
	if err != nil {
		t.Fatalf("form file: %v", err)
	}
	part.Write(img.Bytes())
	w.Close()
	return &buf, w.FormDataContentType()
}

func doMultipart(t *testing.T, r *gin.Engine, path, contentType string, body *bytes.Buffer, cookie *http.Cookie) *httptest.ResponseRecorder {
	t.Helper()
	req := httptest.NewRequest(http.MethodPost, path, body)
	req.Header.Set("Content-Type", contentType)
	if cookie != nil {
		req.AddCookie(cookie)
	}
	w := httptest.NewRecorder()
	r.ServeHTTP(w, req)
	return w
}

// TestScanSeedPacketAPI: a multipart image → a proposal, end to end through the
// router. The extractor is canned; imagenorm runs for real on the uploaded PNG.
func TestScanSeedPacketAPI(t *testing.T) {
	r := packetEngine(t, visionCfg(), func() (vision.SeedPacket, error) {
		return vision.SeedPacket{Species: "garlic", Variety: "Music", Category: "vegetable"}, nil
	})
	cookie := registerAndCookie(t, r, "scan@example.com")
	// A matching plant so the proposal has a candidate.
	createPlantAPI(t, r, cookie, "Music Garlic", 15)

	body, ct := pngUpload(t)
	w := doMultipart(t, r, "/api/v1/seed-lots/scan", ct, body, cookie)
	if w.Code != http.StatusOK {
		t.Fatalf("scan: status %d, body %s", w.Code, w.Body.String())
	}
	res := decodeMap(t, w.Body.Bytes())
	pkt, _ := res["packet"].(map[string]any)
	if pkt["variety"] != "Music" {
		t.Errorf("packet variety = %v", pkt["variety"])
	}
	if cands, _ := res["candidates"].([]any); len(cands) == 0 {
		t.Error("expected a candidate match for Music Garlic")
	}
	if res["suggestedName"] != "Music" {
		t.Errorf("suggestedName = %v", res["suggestedName"])
	}
}

// TestScanSeedPacketErrorsAPI: no image, unreadable bytes, and vision-not-
// configured each get their own clear status.
func TestScanSeedPacketErrorsAPI(t *testing.T) {
	// Vision configured, so we reach imagenorm / the extractor.
	r := packetEngine(t, visionCfg(), func() (vision.SeedPacket, error) {
		return vision.SeedPacket{Variety: "X"}, nil
	})
	cookie := registerAndCookie(t, r, "scanerr@example.com")

	// No file field → 400.
	if w := doMultipart(t, r, "/api/v1/seed-lots/scan", "multipart/form-data; boundary=x", bytes.NewBufferString(""), cookie); w.Code != http.StatusBadRequest {
		t.Errorf("no image = %d, want 400", w.Code)
	}
	// A file that isn't an image → 400 (imagenorm rejects it).
	var buf bytes.Buffer
	mw := multipart.NewWriter(&buf)
	part, _ := mw.CreateFormFile("image", "notes.txt")
	part.Write([]byte("this is not an image"))
	mw.Close()
	if w := doMultipart(t, r, "/api/v1/seed-lots/scan", mw.FormDataContentType(), &buf, cookie); w.Code != http.StatusBadRequest {
		t.Errorf("non-image = %d, want 400", w.Code)
	}

	// Vision NOT configured → 503, even with a valid image.
	r2 := packetEngine(t, localCfg(), func() (vision.SeedPacket, error) { return vision.SeedPacket{}, nil })
	cookie2 := registerAndCookie(t, r2, "novision@example.com")
	body, ct := pngUpload(t)
	if w := doMultipart(t, r2, "/api/v1/seed-lots/scan", ct, body, cookie2); w.Code != http.StatusServiceUnavailable {
		t.Errorf("no vision model = %d, want 503", w.Code)
	}

	// Unauthenticated → 401.
	b3, ct3 := pngUpload(t)
	if w := doMultipart(t, r, "/api/v1/seed-lots/scan", ct3, b3, nil); w.Code != http.StatusUnauthorized {
		t.Errorf("anonymous scan = %d, want 401", w.Code)
	}
}

// TestCreateFromPacketAPI: confirm → plant + lot. No model involved, so the full
// path runs through the router.
func TestCreateFromPacketAPI(t *testing.T) {
	r := packetEngine(t, visionCfg(), func() (vision.SeedPacket, error) { return vision.SeedPacket{}, nil })
	cookie := registerAndCookie(t, r, "confirm@example.com")

	// New plant + lot.
	w := doJSON(t, r, http.MethodPost, "/api/v1/seed-lots/from-packet", map[string]any{
		"newPlant": map[string]any{"name": "Music Garlic", "category": "vegetable", "color": "#4a7c3f", "icon": "🧄", "spacingCm": 15},
		"lot":      map[string]any{"vendor": "Johnny's", "quantity": 8, "unit": "bulbs"},
	}, cookie)
	if w.Code != http.StatusCreated {
		t.Fatalf("new plant confirm: status %d, body %s", w.Code, w.Body.String())
	}
	res := decodeMap(t, w.Body.Bytes())
	if res["plantIsNew"] != true {
		t.Errorf("plantIsNew = %v, want true", res["plantIsNew"])
	}
	plantObj, _ := res["plant"].(map[string]any)
	plantID := int64(plantObj["id"].(float64))
	lotObj, _ := res["lot"].(map[string]any)
	if int64(lotObj["plantId"].(float64)) != plantID {
		t.Errorf("lot not attributed to the new plant")
	}

	// Existing plant + lot.
	w = doJSON(t, r, http.MethodPost, "/api/v1/seed-lots/from-packet", map[string]any{
		"plantId": plantID,
		"lot":     map[string]any{"vendor": "Fedco", "quantity": 10, "unit": "bulbs"},
	}, cookie)
	if w.Code != http.StatusCreated {
		t.Fatalf("existing plant confirm: status %d, body %s", w.Code, w.Body.String())
	}
	if decodeMap(t, w.Body.Bytes())["plantIsNew"] != false {
		t.Error("plantIsNew should be false for an existing plant")
	}

	// Both plantId and newPlant → 400.
	if w := doJSON(t, r, http.MethodPost, "/api/v1/seed-lots/from-packet", map[string]any{
		"plantId":  plantID,
		"newPlant": map[string]any{"name": "X", "category": "vegetable", "color": "#4a7c3f", "icon": "🌱"},
		"lot":      map[string]any{"vendor": "V", "quantity": 1, "unit": "seeds"},
	}, cookie); w.Code != http.StatusBadRequest {
		t.Errorf("both plant choices = %d, want 400", w.Code)
	}

	// Neither → 400.
	if w := doJSON(t, r, http.MethodPost, "/api/v1/seed-lots/from-packet", map[string]any{
		"lot": map[string]any{"vendor": "V", "quantity": 1, "unit": "seeds"},
	}, cookie); w.Code != http.StatusBadRequest {
		t.Errorf("neither plant choice = %d, want 400", w.Code)
	}

	// Unauthenticated → 401.
	if w := doJSON(t, r, http.MethodPost, "/api/v1/seed-lots/from-packet", nil, nil); w.Code != http.StatusUnauthorized {
		t.Errorf("anonymous confirm = %d, want 401", w.Code)
	}
}

// TestCapabilitiesReportsVision: /capabilities advertises vision only when a
// vision model is configured.
func TestCapabilitiesReportsVision(t *testing.T) {
	on := packetEngine(t, visionCfg(), func() (vision.SeedPacket, error) { return vision.SeedPacket{}, nil })
	cookie := registerAndCookie(t, on, "caps@example.com")
	w := doJSON(t, on, http.MethodGet, "/api/v1/capabilities", nil, cookie)
	if decodeMap(t, w.Body.Bytes())["vision"] != true {
		t.Errorf("vision should be true with a model configured: %s", w.Body.String())
	}

	off := packetEngine(t, localCfg(), func() (vision.SeedPacket, error) { return vision.SeedPacket{}, nil })
	cookie2 := registerAndCookie(t, off, "caps2@example.com")
	w = doJSON(t, off, http.MethodGet, "/api/v1/capabilities", nil, cookie2)
	if decodeMap(t, w.Body.Bytes())["vision"] != false {
		t.Errorf("vision should be false with no model: %s", w.Body.String())
	}
}