package test

import (
	domainImage "RenewCMS/internal/domain/image"
	"RenewCMS/internal/infrastructure/config"
	"RenewCMS/internal/infrastructure/storage"
	"bytes"
	"errors"
	"fmt"
	"io"
	"net"
	"net/http"
	"net/http/httptest"
	"strconv"
	"strings"
	"sync"
	"testing"
	"time"
)

const (
	s3TestBucket    = "media"
	s3TestSecret    = "TOPSECRET"
	s3TestAccessKey = "AKIATESTKEY"
)

var s3TestModTime = time.Date(2026, 1, 2, 3, 4, 5, 0, time.UTC)

type fakeS3Object struct {
	data        []byte
	contentType string
	modTime     time.Time
}

type fakeS3Request struct {
	method string
	key    string
	rng    string
}

type fakeS3Server struct {
	server       *httptest.Server
	mu           sync.Mutex
	objects      map[string]fakeS3Object
	bucketStatus int
	failures     map[string]int
	requests     []fakeS3Request
}

func newFakeS3Server(t *testing.T) *fakeS3Server {
	t.Helper()
	fake := &fakeS3Server{
		objects:      map[string]fakeS3Object{},
		bucketStatus: http.StatusOK,
		failures:     map[string]int{},
	}
	listener, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("listen: %v", err)
	}
	fake.server = httptest.NewUnstartedServer(http.HandlerFunc(fake.handle))
	fake.server.Listener = listener
	fake.server.Start()
	t.Cleanup(fake.server.Close)
	return fake
}

func (f *fakeS3Server) put(key string, data []byte, contentType string) {
	f.mu.Lock()
	defer f.mu.Unlock()
	f.objects[key] = fakeS3Object{data: data, contentType: contentType, modTime: s3TestModTime}
}

func (f *fakeS3Server) object(key string) (fakeS3Object, bool) {
	f.mu.Lock()
	defer f.mu.Unlock()
	object, ok := f.objects[key]
	return object, ok
}

func (f *fakeS3Server) failMethod(method string, status int) {
	f.mu.Lock()
	defer f.mu.Unlock()
	f.failures[method] = status
}

func (f *fakeS3Server) setBucketStatus(status int) {
	f.mu.Lock()
	defer f.mu.Unlock()
	f.bucketStatus = status
}

func (f *fakeS3Server) recorded() []fakeS3Request {
	f.mu.Lock()
	defer f.mu.Unlock()
	return append([]fakeS3Request(nil), f.requests...)
}

func (f *fakeS3Server) requestedKeys(method string) []string {
	var keys []string
	for _, request := range f.recorded() {
		if request.method == method {
			keys = append(keys, request.key)
		}
	}
	return keys
}

func (f *fakeS3Server) handle(w http.ResponseWriter, r *http.Request) {
	f.mu.Lock()
	defer f.mu.Unlock()
	trimmed := strings.TrimPrefix(r.URL.Path, "/"+s3TestBucket)
	if r.URL.Path != "/"+s3TestBucket && trimmed == r.URL.Path {
		http.Error(w, "unknown bucket", http.StatusNotFound)
		return
	}
	key := strings.TrimPrefix(trimmed, "/")
	if key == "" {
		w.WriteHeader(f.bucketStatus)
		return
	}
	f.requests = append(f.requests, fakeS3Request{method: r.Method, key: key, rng: r.Header.Get("Range")})
	if status, failing := f.failures[r.Method]; failing {
		writeFakeS3Error(w, r, status, "InternalError")
		return
	}
	switch r.Method {
	case http.MethodPut:
		data, _ := io.ReadAll(r.Body)
		f.objects[key] = fakeS3Object{data: data, contentType: r.Header.Get("Content-Type"), modTime: s3TestModTime}
		w.WriteHeader(http.StatusOK)
	case http.MethodDelete:
		delete(f.objects, key)
		w.WriteHeader(http.StatusNoContent)
	case http.MethodGet, http.MethodHead:
		object, ok := f.objects[key]
		if !ok {
			writeFakeS3Error(w, r, http.StatusNotFound, "NoSuchKey")
			return
		}
		writeFakeS3Object(w, r, object)
	default:
		w.WriteHeader(http.StatusMethodNotAllowed)
	}
}

func writeFakeS3Error(w http.ResponseWriter, r *http.Request, status int, code string) {
	w.Header().Set("Content-Type", "application/xml")
	w.WriteHeader(status)
	if r.Method != http.MethodHead {
		_, _ = fmt.Fprintf(w, `<?xml version="1.0" encoding="UTF-8"?><Error><Code>%s</Code><Message>%s</Message></Error>`, code, code)
	}
}

func writeFakeS3Object(w http.ResponseWriter, r *http.Request, object fakeS3Object) {
	data := object.data
	status := http.StatusOK
	w.Header().Set("Content-Type", object.contentType)
	w.Header().Set("Last-Modified", object.modTime.UTC().Format(http.TimeFormat))
	if rng := r.Header.Get("Range"); rng != "" {
		var start int
		spec := strings.TrimPrefix(rng, "bytes=")
		bounds := strings.SplitN(spec, "-", 2)
		start, _ = strconv.Atoi(bounds[0])
		end := len(data) - 1
		if bounds[1] != "" {
			end, _ = strconv.Atoi(bounds[1])
		}
		w.Header().Set("Content-Range", fmt.Sprintf("bytes %d-%d/%d", start, end, len(data)))
		data = data[start : end+1]
		status = http.StatusPartialContent
	}
	w.Header().Set("Content-Length", strconv.Itoa(len(data)))
	w.WriteHeader(status)
	if r.Method != http.MethodHead {
		_, _ = w.Write(data)
	}
}

func (f *fakeS3Server) config(prefix string) storage.S3Config {
	return storage.S3Config{
		Bucket:          s3TestBucket,
		Region:          "us-east-1",
		Endpoint:        f.server.URL,
		AccessKeyID:     s3TestAccessKey,
		SecretAccessKey: s3TestSecret,
		KeyPrefix:       prefix,
		PathStyle:       true,
		MaxAttempts:     1,
	}
}

func openFakeS3Storage(t *testing.T, fake *fakeS3Server, prefix string) domainImage.Storage {
	t.Helper()
	store, err := storage.Open(storage.Config{Driver: storage.DriverS3, S3: fake.config(prefix)})
	if err != nil {
		t.Fatalf("storage.Open failed: %v", err)
	}
	return store
}

func readAllBlob(t *testing.T, blob domainImage.Blob) []byte {
	t.Helper()
	defer blob.Content.Close()
	data, err := io.ReadAll(blob.Content)
	if err != nil {
		t.Fatalf("read failed: %v", err)
	}
	return data
}

func TestS3StorageSeekThenReadUsesRangedRequests(t *testing.T) {
	fake := newFakeS3Server(t)
	fake.put("a1b2.png", []byte("0123456789"), "image/png")
	store := openFakeS3Storage(t, fake, "")

	blob, err := store.Open("a1b2.png")
	if err != nil {
		t.Fatalf("Open failed: %v", err)
	}
	defer blob.Content.Close()
	seeker, ok := blob.Content.(io.ReadSeeker)
	if !ok {
		t.Fatal("Content is not an io.ReadSeeker")
	}

	end, err := seeker.Seek(0, io.SeekEnd)
	if err != nil || end != 10 {
		t.Fatalf("Seek to end = %d, %v", end, err)
	}
	if _, err := seeker.Seek(4, io.SeekStart); err != nil {
		t.Fatalf("Seek failed: %v", err)
	}
	chunk := make([]byte, 3)
	if _, err := io.ReadFull(seeker, chunk); err != nil || string(chunk) != "456" {
		t.Fatalf("read after seek = %q, %v", chunk, err)
	}
	rest, _ := io.ReadAll(seeker)
	if string(rest) != "789" {
		t.Errorf("remaining bytes = %q", rest)
	}

	var ranges []string
	for _, request := range fake.recorded() {
		if request.method == http.MethodGet {
			ranges = append(ranges, request.rng)
		}
	}
	if len(ranges) != 2 || ranges[0] != "" || ranges[1] != "bytes=4-" {
		t.Errorf("unexpected GET ranges %q", ranges)
	}

	if _, err := seeker.Seek(-1, io.SeekStart); err == nil {
		t.Error("a negative seek must fail")
	}
}

func TestS3StorageNamesThatAreNotPlainAreNeverRequested(t *testing.T) {
	fake := newFakeS3Server(t)
	store := openFakeS3Storage(t, fake, "uploads/")
	for _, name := range []string{"", ".", "..", "../x.png", "a/b.png"} {
		if _, err := store.Open(name); !errors.Is(err, domainImage.ErrBlobNotFound) {
			t.Errorf("Open(%q) = %v, want ErrBlobNotFound", name, err)
		}
		if err := store.Delete(name); err != nil {
			t.Errorf("Delete(%q) = %v, want nil", name, err)
		}
	}
	if requests := fake.recorded(); len(requests) != 0 {
		t.Errorf("no object request expected, got %v", requests)
	}
}

func TestS3StorageErrorsNeverContainTheSecret(t *testing.T) {
	fake := newFakeS3Server(t)
	store := openFakeS3Storage(t, fake, "")
	fake.failMethod(http.MethodPut, http.StatusInternalServerError)
	fake.failMethod(http.MethodGet, http.StatusInternalServerError)
	fake.failMethod(http.MethodDelete, http.StatusInternalServerError)

	_, putErr := store.Put("image/png", bytes.NewReader([]byte("abc")))
	_, openErr := store.Open("a1b2.png")
	deleteErr := store.Delete("a1b2.png")
	for name, err := range map[string]error{"Put": putErr, "Open": openErr, "Delete": deleteErr} {
		if err == nil {
			t.Fatalf("%s must fail", name)
		}
		if strings.Contains(err.Error(), s3TestSecret) {
			t.Errorf("%s error leaks the secret: %v", name, err)
		}
	}
}

func TestS3StorageOpenWithUnreachableEndpointIsSecretFree(t *testing.T) {
	listener, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("listen: %v", err)
	}
	endpoint := "http://" + listener.Addr().String()
	_ = listener.Close()

	_, err = storage.Open(storage.Config{Driver: storage.DriverS3, S3: storage.S3Config{
		Bucket: s3TestBucket, Region: "us-east-1", Endpoint: endpoint, PathStyle: true, MaxAttempts: 1,
		AccessKeyID: s3TestAccessKey, SecretAccessKey: s3TestSecret,
	}})
	if err == nil || !strings.Contains(err.Error(), s3TestBucket) || strings.Contains(err.Error(), s3TestSecret) {
		t.Errorf("expected a bucket-named, secret-free error, got %v", err)
	}
}

func TestS3StorageEndpointWithoutSchemeFollowsTheTLSSetting(t *testing.T) {
	fake := newFakeS3Server(t)
	settings := fake.config("")
	settings.Endpoint = strings.TrimPrefix(fake.server.URL, "http://")
	settings.TLS = false
	store, err := storage.Open(storage.Config{Driver: storage.DriverS3, S3: settings})
	if err != nil {
		t.Fatalf("plain HTTP endpoint without scheme must open, got %v", err)
	}
	if _, err := store.Open("missing.png"); !errors.Is(err, domainImage.ErrBlobNotFound) {
		t.Errorf("expected not found, got %v", err)
	}
}

func TestS3StorageSettingsFromEnv(t *testing.T) {
	setBaseSettingsEnv(t)
	for _, name := range []string{"STORAGE_DRIVER", "S3_BUCKET", "S3_REGION", "S3_ENDPOINT", "S3_ACCESS_KEY_ID", "S3_SECRET_ACCESS_KEY", "S3_KEY_PREFIX", "S3_PATH_STYLE", "S3_TLS"} {
		t.Setenv(name, "")
	}

	t.Run("Every S3 variable is read", func(t *testing.T) {
		t.Setenv("STORAGE_DRIVER", "s3")
		t.Setenv("S3_BUCKET", "media")
		t.Setenv("S3_REGION", "eu-west-3")
		t.Setenv("S3_ENDPOINT", "minio:9000")
		t.Setenv("S3_ACCESS_KEY_ID", "id")
		t.Setenv("S3_SECRET_ACCESS_KEY", "secret")
		t.Setenv("S3_KEY_PREFIX", "cms/")
		t.Setenv("S3_PATH_STYLE", "true")
		t.Setenv("S3_TLS", "false")
		settings, err := config.NewSettingsFromEnv()
		if err != nil {
			t.Fatalf("unexpected error %v", err)
		}
		want := config.S3Settings{Bucket: "media", Region: "eu-west-3", Endpoint: "minio:9000", AccessKeyID: "id", SecretAccessKey: "secret", KeyPrefix: "cms/", PathStyle: true, TLS: false}
		if settings.Storage.Driver != "s3" || settings.Storage.S3 != want {
			t.Errorf("unexpected storage settings %+v", settings.Storage)
		}
	})

	t.Run("Defaults apply", func(t *testing.T) {
		t.Setenv("STORAGE_DRIVER", "s3")
		t.Setenv("S3_BUCKET", "media")
		settings, err := config.NewSettingsFromEnv()
		if err != nil {
			t.Fatalf("unexpected error %v", err)
		}
		s3 := settings.Storage.S3
		if s3.Region != "us-east-1" || s3.PathStyle || !s3.TLS || s3.KeyPrefix != "" || s3.Endpoint != "" {
			t.Errorf("unexpected defaults %+v", s3)
		}
	})

	t.Run("Invalid booleans are rejected", func(t *testing.T) {
		t.Setenv("STORAGE_DRIVER", "s3")
		t.Setenv("S3_BUCKET", "media")
		t.Setenv("S3_PATH_STYLE", "maybe")
		if _, err := config.NewSettingsFromEnv(); err == nil || !strings.Contains(err.Error(), "S3_PATH_STYLE") {
			t.Errorf("expected an S3_PATH_STYLE error, got %v", err)
		}
		t.Setenv("S3_PATH_STYLE", "")
		t.Setenv("S3_TLS", "maybe")
		if _, err := config.NewSettingsFromEnv(); err == nil || !strings.Contains(err.Error(), "S3_TLS") {
			t.Errorf("expected an S3_TLS error, got %v", err)
		}
	})

	t.Run("Required variables by driver", func(t *testing.T) {
		if got := config.StorageRequiredEnvVars("s3"); len(got) != 1 || got[0] != "S3_BUCKET" {
			t.Errorf("unexpected required variables %v", got)
		}
		if got := config.StorageRequiredEnvVars("local"); len(got) != 0 {
			t.Errorf("local requires nothing, got %v", got)
		}
	})
}

func countS3Gets(fake *fakeS3Server) int {
	return len(fake.requestedKeys(http.MethodGet))
}

func openFakeS3Seeker(t *testing.T, fake *fakeS3Server, name string) io.ReadSeekCloser {
	t.Helper()
	store := openFakeS3Storage(t, fake, "")
	blob, err := store.Open(name)
	if err != nil {
		t.Fatalf("Open failed: %v", err)
	}
	seeker, ok := blob.Content.(io.ReadSeekCloser)
	if !ok {
		t.Fatal("Content is not an io.ReadSeekCloser")
	}
	return seeker
}

func TestS3StorageSequentialReadUsesASingleRequest(t *testing.T) {
	fake := newFakeS3Server(t)
	fake.put("a1b2.png", []byte("0123456789"), "image/png")
	seeker := openFakeS3Seeker(t, fake, "a1b2.png")
	defer seeker.Close()

	first := make([]byte, 4)
	if _, err := io.ReadFull(seeker, first); err != nil || string(first) != "0123" {
		t.Fatalf("first read = %q, %v", first, err)
	}
	rest, err := io.ReadAll(seeker)
	if err != nil || string(rest) != "456789" {
		t.Fatalf("rest = %q, %v", rest, err)
	}
	if gets := countS3Gets(fake); gets != 1 {
		t.Errorf("sequential read must use 1 GET, got %d", gets)
	}
}

func TestS3StorageReadAtEndReturnsEOFWithoutRequest(t *testing.T) {
	fake := newFakeS3Server(t)
	fake.put("a1b2.png", []byte("0123456789"), "image/png")
	seeker := openFakeS3Seeker(t, fake, "a1b2.png")
	defer seeker.Close()

	if _, err := seeker.Seek(0, io.SeekEnd); err != nil {
		t.Fatalf("Seek failed: %v", err)
	}
	n, err := seeker.Read(make([]byte, 4))
	if n != 0 || err != io.EOF {
		t.Errorf("Read at end = %d, %v, want 0, EOF", n, err)
	}
	if gets := countS3Gets(fake); gets != 1 {
		t.Errorf("reading at the end must not issue a request, got %d GETs", gets)
	}
}

func TestS3StorageSeekWhenceVariants(t *testing.T) {
	fake := newFakeS3Server(t)
	fake.put("a1b2.png", []byte("0123456789"), "image/png")
	seeker := openFakeS3Seeker(t, fake, "a1b2.png")
	defer seeker.Close()

	if pos, err := seeker.Seek(-3, io.SeekEnd); err != nil || pos != 7 {
		t.Fatalf("SeekEnd(-3) = %d, %v", pos, err)
	}
	if pos, err := seeker.Seek(-2, io.SeekCurrent); err != nil || pos != 5 {
		t.Fatalf("SeekCurrent(-2) = %d, %v", pos, err)
	}
	chunk := make([]byte, 2)
	if _, err := io.ReadFull(seeker, chunk); err != nil || string(chunk) != "56" {
		t.Errorf("read after seeks = %q, %v", chunk, err)
	}
	if _, err := seeker.Seek(0, 99); err == nil {
		t.Error("an invalid whence must fail")
	}
}

func TestS3StorageReadAfterCloseReopensTheObject(t *testing.T) {
	fake := newFakeS3Server(t)
	fake.put("a1b2.png", []byte("0123456789"), "image/png")
	seeker := openFakeS3Seeker(t, fake, "a1b2.png")

	head := make([]byte, 3)
	if _, err := io.ReadFull(seeker, head); err != nil {
		t.Fatalf("read failed: %v", err)
	}
	if err := seeker.Close(); err != nil {
		t.Fatalf("Close failed: %v", err)
	}
	rest, err := io.ReadAll(seeker)
	if err != nil || string(rest) != "3456789" {
		t.Errorf("read after Close = %q, %v", rest, err)
	}
	_ = seeker.Close()
	if gets := countS3Gets(fake); gets != 2 {
		t.Errorf("expected 2 GETs, got %d", gets)
	}
}

func TestS3StorageMaxAttemptsLimitsRetries(t *testing.T) {
	fake := newFakeS3Server(t)
	store := openFakeS3Storage(t, fake, "")
	fake.failMethod(http.MethodGet, http.StatusInternalServerError)

	if _, err := store.Open("a1b2.png"); err == nil {
		t.Fatal("Open must fail")
	}
	if gets := countS3Gets(fake); gets != 1 {
		t.Errorf("MaxAttempts=1 must issue exactly 1 GET, got %d", gets)
	}
}

func TestS3StorageTLSEndpointWithoutSchemeUsesHTTPS(t *testing.T) {
	fake := newFakeS3Server(t)
	settings := fake.config("")
	settings.Endpoint = strings.TrimPrefix(fake.server.URL, "http://")
	settings.TLS = true
	_, err := storage.Open(storage.Config{Driver: storage.DriverS3, S3: settings})
	if err == nil || !strings.Contains(err.Error(), s3TestBucket) {
		t.Errorf("https against a plain HTTP server must fail naming the bucket, got %v", err)
	}
}

func TestS3StorageRedactsSecretsFoundInTransportErrors(t *testing.T) {
	listener, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("listen: %v", err)
	}
	endpoint := "http://" + listener.Addr().String() + "/" + s3TestAccessKey + "/" + s3TestSecret
	_ = listener.Close()

	_, err = storage.Open(storage.Config{Driver: storage.DriverS3, S3: storage.S3Config{
		Bucket: s3TestBucket, Region: "us-east-1", Endpoint: endpoint, PathStyle: true, MaxAttempts: 1,
		AccessKeyID: s3TestAccessKey, SecretAccessKey: s3TestSecret,
	}})
	if err == nil {
		t.Fatal("expected an error")
	}
	if strings.Contains(err.Error(), s3TestSecret) || strings.Contains(err.Error(), s3TestAccessKey) {
		t.Errorf("credentials leaked: %v", err)
	}
	if !strings.Contains(err.Error(), "***") {
		t.Errorf("expected redaction markers, got %v", err)
	}
}

func TestS3StorageReadFailsWhenTheRangedRequestFails(t *testing.T) {
	fake := newFakeS3Server(t)
	fake.put("a1b2.png", []byte("0123456789"), "image/png")
	seeker := openFakeS3Seeker(t, fake, "a1b2.png")
	defer seeker.Close()

	if _, err := seeker.Seek(4, io.SeekStart); err != nil {
		t.Fatalf("Seek failed: %v", err)
	}
	fake.failMethod(http.MethodGet, http.StatusInternalServerError)
	n, err := seeker.Read(make([]byte, 3))
	if err == nil || n != 0 {
		t.Errorf("Read = %d, %v, want a failure with no bytes", n, err)
	}
}